36 files changed, 3356 insertions, 1715 deletions

diff --git a/vendor/tracing-subscriber-0.3.3/src/fmt/format/pretty.rs b/vendor/tracing-subscriber-0.3.3/src/fmt/format/pretty.rs
deleted file mode 100644
index 3e47e2d93..000000000
--- a/vendor/tracing-subscriber-0.3.3/src/fmt/format/pretty.rs
+++ /dev/null
@@ -1,415 +0,0 @@
-use super::*;
-use crate::{
-    field::{VisitFmt, VisitOutput},
-    fmt::fmt_layer::{FmtContext, FormattedFields},
-    registry::LookupSpan,
-};
-
-use std::fmt;
-use tracing_core::{
-    field::{self, Field},
-    Event, Level, Subscriber,
-};
-
-#[cfg(feature = "tracing-log")]
-use tracing_log::NormalizeEvent;
-
-use ansi_term::{Colour, Style};
-
-/// An excessively pretty, human-readable event formatter.
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub struct Pretty {
-    display_location: bool,
-}
-
-/// The [visitor] produced by [`Pretty`]'s [`MakeVisitor`] implementation.
-///
-/// [visitor]: field::Visit
-/// [`MakeVisitor`]: crate::field::MakeVisitor
-#[derive(Debug)]
-pub struct PrettyVisitor<'a> {
-    writer: Writer<'a>,
-    is_empty: bool,
-    style: Style,
-    result: fmt::Result,
-}
-
-/// An excessively pretty, human-readable [`MakeVisitor`] implementation.
-///
-/// [`MakeVisitor`]: crate::field::MakeVisitor
-#[derive(Debug)]
-pub struct PrettyFields {
-    /// A value to override the provided `Writer`'s ANSI formatting
-    /// configuration.
-    ///
-    /// If this is `Some`, we override the `Writer`'s ANSI setting. This is
-    /// necessary in order to continue supporting the deprecated
-    /// `PrettyFields::with_ansi` method. If it is `None`, we don't override the
-    /// ANSI formatting configuration (because the deprecated method was not
-    /// called).
-    // TODO: when `PrettyFields::with_ansi` is removed, we can get rid
-    // of this entirely.
-    ansi: Option<bool>,
-}
-
-// === impl Pretty ===
-
-impl Default for Pretty {
-    fn default() -> Self {
-        Self {
-            display_location: true,
-        }
-    }
-}
-
-impl Pretty {
-    fn style_for(level: &Level) -> Style {
-        match *level {
-            Level::TRACE => Style::new().fg(Colour::Purple),
-            Level::DEBUG => Style::new().fg(Colour::Blue),
-            Level::INFO => Style::new().fg(Colour::Green),
-            Level::WARN => Style::new().fg(Colour::Yellow),
-            Level::ERROR => Style::new().fg(Colour::Red),
-        }
-    }
-
-    /// Sets whether the event's source code location is displayed.
-    ///
-    /// This defaults to `true`.
-    pub fn with_source_location(self, display_location: bool) -> Self {
-        Self {
-            display_location,
-            ..self
-        }
-    }
-}
-
-impl<T> Format<Pretty, T> {
-    /// Sets whether or not the source code location from which an event
-    /// originated is displayed.
-    ///
-    /// This defaults to `true`.
-    pub fn with_source_location(mut self, display_location: bool) -> Self {
-        self.format = self.format.with_source_location(display_location);
-        self
-    }
-}
-
-impl<C, N, T> FormatEvent<C, N> for Format<Pretty, T>
-where
-    C: Subscriber + for<'a> LookupSpan<'a>,
-    N: for<'a> FormatFields<'a> + 'static,
-    T: FormatTime,
-{
-    fn format_event(
-        &self,
-        ctx: &FmtContext<'_, C, N>,
-        mut writer: Writer<'_>,
-        event: &Event<'_>,
-    ) -> fmt::Result {
-        #[cfg(feature = "tracing-log")]
-        let normalized_meta = event.normalized_metadata();
-        #[cfg(feature = "tracing-log")]
-        let meta = normalized_meta.as_ref().unwrap_or_else(|| event.metadata());
-        #[cfg(not(feature = "tracing-log"))]
-        let meta = event.metadata();
-        write!(&mut writer, "  ")?;
-
-        // if the `Format` struct *also* has an ANSI color configuration,
-        // override the writer...the API for configuring ANSI color codes on the
-        // `Format` struct is deprecated, but we still need to honor those
-        // configurations.
-        if let Some(ansi) = self.ansi {
-            writer = writer.with_ansi(ansi);
-        }
-
-        self.format_timestamp(&mut writer)?;
-
-        let style = if self.display_level && writer.has_ansi_escapes() {
-            Pretty::style_for(meta.level())
-        } else {
-            Style::new()
-        };
-
-        if self.display_level {
-            write!(
-                writer,
-                "{} ",
-                super::FmtLevel::new(meta.level(), writer.has_ansi_escapes())
-            )?;
-        }
-
-        if self.display_target {
-            let target_style = if writer.has_ansi_escapes() {
-                style.bold()
-            } else {
-                style
-            };
-            write!(
-                writer,
-                "{}{}{}: ",
-                target_style.prefix(),
-                meta.target(),
-                target_style.infix(style)
-            )?;
-        }
-        let mut v = PrettyVisitor::new(writer.by_ref(), true).with_style(style);
-        event.record(&mut v);
-        v.finish()?;
-        writer.write_char('\n')?;
-
-        let dimmed = if writer.has_ansi_escapes() {
-            Style::new().dimmed().italic()
-        } else {
-            Style::new()
-        };
-        let thread = self.display_thread_name || self.display_thread_id;
-        if let (true, Some(file), Some(line)) =
-            (self.format.display_location, meta.file(), meta.line())
-        {
-            write!(
-                writer,
-                "    {} {}:{}{}",
-                dimmed.paint("at"),
-                file,
-                line,
-                dimmed.paint(if thread { " " } else { "\n" })
-            )?;
-        } else if thread {
-            write!(writer, "    ")?;
-        }
-
-        if thread {
-            write!(writer, "{} ", dimmed.paint("on"))?;
-            let thread = std::thread::current();
-            if self.display_thread_name {
-                if let Some(name) = thread.name() {
-                    write!(writer, "{}", name)?;
-                    if self.display_thread_id {
-                        write!(writer, " ({:?})", thread.id())?;
-                    }
-                } else if !self.display_thread_id {
-                    write!(writer, " {:?}", thread.id())?;
-                }
-            } else if self.display_thread_id {
-                write!(writer, " {:?}", thread.id())?;
-            }
-            writer.write_char('\n')?;
-        }
-
-        let bold = writer.bold();
-        let span = event
-            .parent()
-            .and_then(|id| ctx.span(id))
-            .or_else(|| ctx.lookup_current());
-
-        let scope = span.into_iter().flat_map(|span| span.scope());
-
-        for span in scope {
-            let meta = span.metadata();
-            if self.display_target {
-                write!(
-                    writer,
-                    "    {} {}::{}",
-                    dimmed.paint("in"),
-                    meta.target(),
-                    bold.paint(meta.name()),
-                )?;
-            } else {
-                write!(
-                    writer,
-                    "    {} {}",
-                    dimmed.paint("in"),
-                    bold.paint(meta.name()),
-                )?;
-            }
-
-            let ext = span.extensions();
-            let fields = &ext
-                .get::<FormattedFields<N>>()
-                .expect("Unable to find FormattedFields in extensions; this is a bug");
-            if !fields.is_empty() {
-                write!(writer, " {} {}", dimmed.paint("with"), fields)?;
-            }
-            writer.write_char('\n')?;
-        }
-
-        writer.write_char('\n')
-    }
-}
-
-impl<'writer> FormatFields<'writer> for Pretty {
-    fn format_fields<R: RecordFields>(&self, writer: Writer<'writer>, fields: R) -> fmt::Result {
-        let mut v = PrettyVisitor::new(writer, false);
-        fields.record(&mut v);
-        v.finish()
-    }
-
-    fn add_fields(
-        &self,
-        current: &'writer mut FormattedFields<Self>,
-        fields: &span::Record<'_>,
-    ) -> fmt::Result {
-        let empty = current.is_empty();
-        let writer = current.as_writer();
-        let mut v = PrettyVisitor::new(writer, empty);
-        fields.record(&mut v);
-        v.finish()
-    }
-}
-
-// === impl PrettyFields ===
-
-impl Default for PrettyFields {
-    fn default() -> Self {
-        Self::new()
-    }
-}
-
-impl PrettyFields {
-    /// Returns a new default [`PrettyFields`] implementation.
-    pub fn new() -> Self {
-        // By default, don't override the `Writer`'s ANSI colors
-        // configuration. We'll only do this if the user calls the
-        // deprecated `PrettyFields::with_ansi` method.
-        Self { ansi: None }
-    }
-
-    /// Enable ANSI encoding for formatted fields.
-    #[deprecated(
-        since = "0.3.3",
-        note = "Use `fmt::Subscriber::with_ansi` or `fmt::Layer::with_ansi` instead."
-    )]
-    pub fn with_ansi(self, ansi: bool) -> Self {
-        Self {
-            ansi: Some(ansi),
-            ..self
-        }
-    }
-}
-
-impl<'a> MakeVisitor<Writer<'a>> for PrettyFields {
-    type Visitor = PrettyVisitor<'a>;
-
-    #[inline]
-    fn make_visitor(&self, mut target: Writer<'a>) -> Self::Visitor {
-        if let Some(ansi) = self.ansi {
-            target = target.with_ansi(ansi);
-        }
-        PrettyVisitor::new(target, true)
-    }
-}
-
-// === impl PrettyVisitor ===
-
-impl<'a> PrettyVisitor<'a> {
-    /// Returns a new default visitor that formats to the provided `writer`.
-    ///
-    /// # Arguments
-    /// - `writer`: the writer to format to.
-    /// - `is_empty`: whether or not any fields have been previously written to
-    ///   that writer.
-    pub fn new(writer: Writer<'a>, is_empty: bool) -> Self {
-        Self {
-            writer,
-            is_empty,
-            style: Style::default(),
-            result: Ok(()),
-        }
-    }
-
-    pub(crate) fn with_style(self, style: Style) -> Self {
-        Self { style, ..self }
-    }
-
-    fn write_padded(&mut self, value: &impl fmt::Debug) {
-        let padding = if self.is_empty {
-            self.is_empty = false;
-            ""
-        } else {
-            ", "
-        };
-        self.result = write!(self.writer, "{}{:?}", padding, value);
-    }
-
-    fn bold(&self) -> Style {
-        if self.writer.has_ansi_escapes() {
-            self.style.bold()
-        } else {
-            Style::new()
-        }
-    }
-}
-
-impl<'a> field::Visit for PrettyVisitor<'a> {
-    fn record_str(&mut self, field: &Field, value: &str) {
-        if self.result.is_err() {
-            return;
-        }
-
-        if field.name() == "message" {
-            self.record_debug(field, &format_args!("{}", value))
-        } else {
-            self.record_debug(field, &value)
-        }
-    }
-
-    fn record_error(&mut self, field: &Field, value: &(dyn std::error::Error + 'static)) {
-        if let Some(source) = value.source() {
-            let bold = self.bold();
-            self.record_debug(
-                field,
-                &format_args!(
-                    "{}, {}{}.sources{}: {}",
-                    value,
-                    bold.prefix(),
-                    field,
-                    bold.infix(self.style),
-                    ErrorSourceList(source),
-                ),
-            )
-        } else {
-            self.record_debug(field, &format_args!("{}", value))
-        }
-    }
-
-    fn record_debug(&mut self, field: &Field, value: &dyn fmt::Debug) {
-        if self.result.is_err() {
-            return;
-        }
-        let bold = self.bold();
-        match field.name() {
-            "message" => self.write_padded(&format_args!("{}{:?}", self.style.prefix(), value,)),
-            // Skip fields that are actually log metadata that have already been handled
-            #[cfg(feature = "tracing-log")]
-            name if name.starts_with("log.") => self.result = Ok(()),
-            name if name.starts_with("r#") => self.write_padded(&format_args!(
-                "{}{}{}: {:?}",
-                bold.prefix(),
-                &name[2..],
-                bold.infix(self.style),
-                value
-            )),
-            name => self.write_padded(&format_args!(
-                "{}{}{}: {:?}",
-                bold.prefix(),
-                name,
-                bold.infix(self.style),
-                value
-            )),
-        };
-    }
-}
-
-impl<'a> VisitOutput<fmt::Result> for PrettyVisitor<'a> {
-    fn finish(mut self) -> fmt::Result {
-        write!(&mut self.writer, "{}", self.style.suffix())?;
-        self.result
-    }
-}
-
-impl<'a> VisitFmt for PrettyVisitor<'a> {
-    fn writer(&mut self) -> &mut dyn fmt::Write {
-        &mut self.writer
-    }
-}
diff --git a/vendor/tracing-subscriber-0.3.3/src/fmt/time/time_crate.rs b/vendor/tracing-subscriber-0.3.3/src/fmt/time/time_crate.rs
deleted file mode 100644
index 64d274365..000000000
--- a/vendor/tracing-subscriber-0.3.3/src/fmt/time/time_crate.rs
+++ /dev/null
@@ -1,276 +0,0 @@
-use crate::fmt::{format::Writer, time::FormatTime, writer::WriteAdaptor};
-use std::fmt;
-use time::{format_description::well_known, formatting::Formattable, OffsetDateTime};
-
-/// Formats the current [local time] using a [formatter] from the [`time` crate].
-///
-/// To format the current [UTC time] instead, use the [`UtcTime`] type.
-///
-/// [local time]: https://docs.rs/time/0.3/time/struct.OffsetDateTime.html#method.now_local
-/// [UTC time]: https://docs.rs/time/0.3/time/struct.OffsetDateTime.html#method.now_utc
-/// [formatter]: https://docs.rs/time/0.3/time/formatting/trait.Formattable.html
-/// [`time` crate]: https://docs.rs/time/0.3/time/
-#[derive(Clone, Debug)]
-#[cfg_attr(docsrs, doc(cfg(all(feature = "time", feature = "local-time"))))]
-#[cfg(feature = "local-time")]
-pub struct LocalTime<F> {
-    format: F,
-}
-
-/// Formats the current [UTC time] using a [formatter] from the [`time` crate].
-///
-/// To format the current [local time] instead, use the [`LocalTime`] type.
-///
-/// [local time]: https://docs.rs/time/0.3/time/struct.OffsetDateTime.html#method.now_local
-/// [UTC time]: https://docs.rs/time/0.3/time/struct.OffsetDateTime.html#method.now_utc
-/// [formatter]: https://docs.rs/time/0.3/time/formatting/trait.Formattable.html
-/// [`time` crate]: https://docs.rs/time/0.3/time/
-#[cfg_attr(docsrs, doc(cfg(feature = "time")))]
-#[derive(Clone, Debug)]
-pub struct UtcTime<F> {
-    format: F,
-}
-
-// === impl LocalTime ===
-
-#[cfg(feature = "local-time")]
-impl LocalTime<well_known::Rfc3339> {
-    /// Returns a formatter that formats the current [local time] in the
-    /// [RFC 3339] format (a subset of the [ISO 8601] timestamp format).
-    ///
-    /// # Examples
-    ///
-    /// ```
-    /// use tracing_subscriber::fmt::{self, time};
-    ///
-    /// let collector = tracing_subscriber::fmt()
-    ///     .with_timer(time::LocalTime::rfc_3339());
-    /// # drop(collector);
-    /// ```
-    ///
-    /// [local time]: https://docs.rs/time/0.3/time/struct.OffsetDateTime.html#method.now_local
-    /// [RFC 3339]: https://datatracker.ietf.org/doc/html/rfc3339
-    /// [ISO 8601]: https://en.wikipedia.org/wiki/ISO_8601
-    pub fn rfc_3339() -> Self {
-        Self::new(well_known::Rfc3339)
-    }
-}
-
-#[cfg(feature = "local-time")]
-impl<F: Formattable> LocalTime<F> {
-    /// Returns a formatter that formats the current [local time] using the
-    /// [`time` crate] with the provided provided format. The format may be any
-    /// type that implements the [`Formattable`] trait.
-    ///
-    /// Typically, the format will be a format description string, or one of the
-    /// `time` crate's [well-known formats].
-    ///
-    /// If the format description is statically known, then the
-    /// [`format_description!`] macro should be used. This is identical to the
-    /// [`time::format_description::parse`] method, but runs at compile-time,
-    /// throwing an error if the format description is invalid. If the desired format
-    /// is not known statically (e.g., a user is providing a format string), then the
-    /// [`time::format_description::parse`] method should be used. Note that this
-    /// method is fallible.
-    ///
-    /// See the [`time` book] for details on the format description syntax.
-    ///
-    /// # Examples
-    ///
-    /// Using the [`format_description!`] macro:
-    ///
-    /// ```
-    /// use tracing_subscriber::fmt::{self, time::LocalTime};
-    /// use time::macros::format_description;
-    ///
-    /// let timer = LocalTime::new(format_description!("[hour]:[minute]:[second]"));
-    /// let collector = tracing_subscriber::fmt()
-    ///     .with_timer(timer);
-    /// # drop(collector);
-    /// ```
-    ///
-    /// Using [`time::format_description::parse`]:
-    ///
-    /// ```
-    /// use tracing_subscriber::fmt::{self, time::LocalTime};
-    ///
-    /// let time_format = time::format_description::parse("[hour]:[minute]:[second]")
-    ///     .expect("format string should be valid!");
-    /// let timer = LocalTime::new(time_format);
-    /// let collector = tracing_subscriber::fmt()
-    ///     .with_timer(timer);
-    /// # drop(collector);
-    /// ```
-    ///
-    /// Using the [`format_description!`] macro requires enabling the `time`
-    /// crate's "macros" feature flag.
-    ///
-    /// Using a [well-known format][well-known formats] (this is equivalent to
-    /// [`LocalTime::rfc_3339`]):
-    ///
-    /// ```
-    /// use tracing_subscriber::fmt::{self, time::LocalTime};
-    ///
-    /// let timer = LocalTime::new(time::format_description::well_known::Rfc3339);
-    /// let collector = tracing_subscriber::fmt()
-    ///     .with_timer(timer);
-    /// # drop(collector);
-    /// ```
-    ///
-    /// [local time]: https://docs.rs/time/latest/time/struct.OffsetDateTime.html#method.now_local
-    /// [`time` crate]: https://docs.rs/time/0.3/time/
-    /// [`Formattable`]: https://docs.rs/time/0.3/time/formatting/trait.Formattable.html
-    /// [well-known formats]: https://docs.rs/time/0.3/time/format_description/well_known/index.html
-    /// [`format_description!`]: https://docs.rs/time/0.3/time/macros/macro.format_description.html
-    /// [`time::format_description::parse`]: https://docs.rs/time/0.3/time/format_description/fn.parse.html
-    /// [`time` book]: https://time-rs.github.io/book/api/format-description.html
-    pub fn new(format: F) -> Self {
-        Self { format }
-    }
-}
-
-#[cfg(feature = "local-time")]
-impl<F> FormatTime for LocalTime<F>
-where
-    F: Formattable,
-{
-    fn format_time(&self, w: &mut Writer<'_>) -> fmt::Result {
-        let now = OffsetDateTime::now_local().map_err(|_| fmt::Error)?;
-        format_datetime(now, w, &self.format)
-    }
-}
-
-#[cfg(feature = "local-time")]
-impl<F> Default for LocalTime<F>
-where
-    F: Formattable + Default,
-{
-    fn default() -> Self {
-        Self::new(F::default())
-    }
-}
-
-// === impl UtcTime ===
-
-impl UtcTime<well_known::Rfc3339> {
-    /// Returns a formatter that formats the current [UTC time] in the
-    /// [RFC 3339] format, which is a subset of the [ISO 8601] timestamp format.
-    ///
-    /// # Examples
-    ///
-    /// ```
-    /// use tracing_subscriber::fmt::{self, time};
-    ///
-    /// let collector = tracing_subscriber::fmt()
-    ///     .with_timer(time::UtcTime::rfc_3339());
-    /// # drop(collector);
-    /// ```
-    ///
-    /// [local time]: https://docs.rs/time/0.3/time/struct.OffsetDateTime.html#method.now_utc
-    /// [RFC 3339]: https://datatracker.ietf.org/doc/html/rfc3339
-    /// [ISO 8601]: https://en.wikipedia.org/wiki/ISO_8601
-    pub fn rfc_3339() -> Self {
-        Self::new(well_known::Rfc3339)
-    }
-}
-
-impl<F: Formattable> UtcTime<F> {
-    /// Returns a formatter that formats the current [UTC time] using the
-    /// [`time` crate], with the provided provided format. The format may be any
-    /// type that implements the [`Formattable`] trait.
-    ///
-    /// Typically, the format will be a format description string, or one of the
-    /// `time` crate's [well-known formats].
-    ///
-    /// If the format description is statically known, then the
-    /// [`format_description!`] macro should be used. This is identical to the
-    /// [`time::format_description::parse`] method, but runs at compile-time,
-    /// failing  an error if the format description is invalid. If the desired format
-    /// is not known statically (e.g., a user is providing a format string), then the
-    /// [`time::format_description::parse`] method should be used. Note that this
-    /// method is fallible.
-    ///
-    /// See the [`time` book] for details on the format description syntax.
-    ///
-    /// # Examples
-    ///
-    /// Using the [`format_description!`] macro:
-    ///
-    /// ```
-    /// use tracing_subscriber::fmt::{self, time::UtcTime};
-    /// use time::macros::format_description;
-    ///
-    /// let timer = UtcTime::new(format_description!("[hour]:[minute]:[second]"));
-    /// let collector = tracing_subscriber::fmt()
-    ///     .with_timer(timer);
-    /// # drop(collector);
-    /// ```
-    ///
-    /// Using the [`format_description!`] macro requires enabling the `time`
-    /// crate's "macros" feature flag.
-    ///
-    /// Using [`time::format_description::parse`]:
-    ///
-    /// ```
-    /// use tracing_subscriber::fmt::{self, time::UtcTime};
-    ///
-    /// let time_format = time::format_description::parse("[hour]:[minute]:[second]")
-    ///     .expect("format string should be valid!");
-    /// let timer = UtcTime::new(time_format);
-    /// let collector = tracing_subscriber::fmt()
-    ///     .with_timer(timer);
-    /// # drop(collector);
-    /// ```
-    ///
-    /// Using a [well-known format][well-known formats] (this is equivalent to
-    /// [`UtcTime::rfc_3339`]):
-    ///
-    /// ```
-    /// use tracing_subscriber::fmt::{self, time::UtcTime};
-    ///
-    /// let timer = UtcTime::new(time::format_description::well_known::Rfc3339);
-    /// let collector = tracing_subscriber::fmt()
-    ///     .with_timer(timer);
-    /// # drop(collector);
-    /// ```
-    ///
-    /// [UTC time]: https://docs.rs/time/latest/time/struct.OffsetDateTime.html#method.now_utc
-    /// [`time` crate]: https://docs.rs/time/0.3/time/
-    /// [`Formattable`]: https://docs.rs/time/0.3/time/formatting/trait.Formattable.html
-    /// [well-known formats]: https://docs.rs/time/0.3/time/format_description/well_known/index.html
-    /// [`format_description!`]: https://docs.rs/time/0.3/time/macros/macro.format_description.html
-    /// [`time::format_description::parse`]: https://docs.rs/time/0.3/time/format_description/fn.parse.html
-    /// [`time` book]: https://time-rs.github.io/book/api/format-description.html
-    pub fn new(format: F) -> Self {
-        Self { format }
-    }
-}
-
-impl<F> FormatTime for UtcTime<F>
-where
-    F: Formattable,
-{
-    fn format_time(&self, w: &mut Writer<'_>) -> fmt::Result {
-        format_datetime(OffsetDateTime::now_utc(), w, &self.format)
-    }
-}
-
-impl<F> Default for UtcTime<F>
-where
-    F: Formattable + Default,
-{
-    fn default() -> Self {
-        Self::new(F::default())
-    }
-}
-
-fn format_datetime(
-    now: OffsetDateTime,
-    into: &mut Writer<'_>,
-    fmt: &impl Formattable,
-) -> fmt::Result {
-    let mut into = WriteAdaptor::new(into);
-    now.format_into(&mut into, fmt)
-        .map_err(|_| fmt::Error)
-        .map(|_| ())
-}
diff --git a/vendor/tracing-subscriber-0.3.3/src/reload.rs b/vendor/tracing-subscriber-0.3.3/src/reload.rs
deleted file mode 100644
index b8ec67dfa..000000000
--- a/vendor/tracing-subscriber-0.3.3/src/reload.rs
+++ /dev/null
@@ -1,237 +0,0 @@
-//! Wrapper for a `Layer` to allow it to be dynamically reloaded.
-//!
-//! This module provides a [`Layer` type] which wraps another type implementing
-//! the [`Layer` trait], allowing the wrapped type to be replaced with another
-//! instance of that type at runtime.
-//!
-//! This can be used in cases where a subset of `Subscriber` functionality
-//! should be dynamically reconfigured, such as when filtering directives may
-//! change at runtime. Note that this layer introduces a (relatively small)
-//! amount of overhead, and should thus only be used as needed.
-//!
-//! [`Layer` type]: struct.Layer.html
-//! [`Layer` trait]: ../layer/trait.Layer.html
-use crate::layer;
-use crate::sync::RwLock;
-
-use std::{
-    error, fmt,
-    marker::PhantomData,
-    sync::{Arc, Weak},
-};
-use tracing_core::{
-    callsite, span,
-    subscriber::{Interest, Subscriber},
-    Event, Metadata,
-};
-
-/// Wraps a `Layer`, allowing it to be reloaded dynamically at runtime.
-#[derive(Debug)]
-pub struct Layer<L, S> {
-    // TODO(eliza): this once used a `crossbeam_util::ShardedRwLock`. We may
-    // eventually wish to replace it with a sharded lock implementation on top
-    // of our internal `RwLock` wrapper type. If possible, we should profile
-    // this first to determine if it's necessary.
-    inner: Arc<RwLock<L>>,
-    _s: PhantomData<fn(S)>,
-}
-
-/// Allows reloading the state of an associated `Layer`.
-#[derive(Debug)]
-pub struct Handle<L, S> {
-    inner: Weak<RwLock<L>>,
-    _s: PhantomData<fn(S)>,
-}
-
-/// Indicates that an error occurred when reloading a layer.
-#[derive(Debug)]
-pub struct Error {
-    kind: ErrorKind,
-}
-
-#[derive(Debug)]
-enum ErrorKind {
-    SubscriberGone,
-    Poisoned,
-}
-
-// ===== impl Layer =====
-
-impl<L, S> crate::Layer<S> for Layer<L, S>
-where
-    L: crate::Layer<S> + 'static,
-    S: Subscriber,
-{
-    fn on_layer(&mut self, subscriber: &mut S) {
-        try_lock!(self.inner.write(), else return).on_layer(subscriber);
-    }
-
-    #[inline]
-    fn register_callsite(&self, metadata: &'static Metadata<'static>) -> Interest {
-        try_lock!(self.inner.read(), else return Interest::sometimes()).register_callsite(metadata)
-    }
-
-    #[inline]
-    fn enabled(&self, metadata: &Metadata<'_>, ctx: layer::Context<'_, S>) -> bool {
-        try_lock!(self.inner.read(), else return false).enabled(metadata, ctx)
-    }
-
-    #[inline]
-    fn on_new_span(&self, attrs: &span::Attributes<'_>, id: &span::Id, ctx: layer::Context<'_, S>) {
-        try_lock!(self.inner.read()).on_new_span(attrs, id, ctx)
-    }
-
-    #[inline]
-    fn on_record(&self, span: &span::Id, values: &span::Record<'_>, ctx: layer::Context<'_, S>) {
-        try_lock!(self.inner.read()).on_record(span, values, ctx)
-    }
-
-    #[inline]
-    fn on_follows_from(&self, span: &span::Id, follows: &span::Id, ctx: layer::Context<'_, S>) {
-        try_lock!(self.inner.read()).on_follows_from(span, follows, ctx)
-    }
-
-    #[inline]
-    fn on_event(&self, event: &Event<'_>, ctx: layer::Context<'_, S>) {
-        try_lock!(self.inner.read()).on_event(event, ctx)
-    }
-
-    #[inline]
-    fn on_enter(&self, id: &span::Id, ctx: layer::Context<'_, S>) {
-        try_lock!(self.inner.read()).on_enter(id, ctx)
-    }
-
-    #[inline]
-    fn on_exit(&self, id: &span::Id, ctx: layer::Context<'_, S>) {
-        try_lock!(self.inner.read()).on_exit(id, ctx)
-    }
-
-    #[inline]
-    fn on_close(&self, id: span::Id, ctx: layer::Context<'_, S>) {
-        try_lock!(self.inner.read()).on_close(id, ctx)
-    }
-
-    #[inline]
-    fn on_id_change(&self, old: &span::Id, new: &span::Id, ctx: layer::Context<'_, S>) {
-        try_lock!(self.inner.read()).on_id_change(old, new, ctx)
-    }
-}
-
-impl<L, S> Layer<L, S>
-where
-    L: crate::Layer<S> + 'static,
-    S: Subscriber,
-{
-    /// Wraps the given `Layer`, returning a `Layer` and a `Handle` that allows
-    /// the inner type to be modified at runtime.
-    pub fn new(inner: L) -> (Self, Handle<L, S>) {
-        let this = Self {
-            inner: Arc::new(RwLock::new(inner)),
-            _s: PhantomData,
-        };
-        let handle = this.handle();
-        (this, handle)
-    }
-
-    /// Returns a `Handle` that can be used to reload the wrapped `Layer`.
-    pub fn handle(&self) -> Handle<L, S> {
-        Handle {
-            inner: Arc::downgrade(&self.inner),
-            _s: PhantomData,
-        }
-    }
-}
-
-// ===== impl Handle =====
-
-impl<L, S> Handle<L, S>
-where
-    L: crate::Layer<S> + 'static,
-    S: Subscriber,
-{
-    /// Replace the current layer with the provided `new_layer`.
-    pub fn reload(&self, new_layer: impl Into<L>) -> Result<(), Error> {
-        self.modify(|layer| {
-            *layer = new_layer.into();
-        })
-    }
-
-    /// Invokes a closure with a mutable reference to the current layer,
-    /// allowing it to be modified in place.
-    pub fn modify(&self, f: impl FnOnce(&mut L)) -> Result<(), Error> {
-        let inner = self.inner.upgrade().ok_or(Error {
-            kind: ErrorKind::SubscriberGone,
-        })?;
-
-        let mut lock = try_lock!(inner.write(), else return Err(Error::poisoned()));
-        f(&mut *lock);
-        // Release the lock before rebuilding the interest cache, as that
-        // function will lock the new layer.
-        drop(lock);
-
-        callsite::rebuild_interest_cache();
-        Ok(())
-    }
-
-    /// Returns a clone of the layer's current value if it still exists.
-    /// Otherwise, if the subscriber has been dropped, returns `None`.
-    pub fn clone_current(&self) -> Option<L>
-    where
-        L: Clone,
-    {
-        self.with_current(L::clone).ok()
-    }
-
-    /// Invokes a closure with a borrowed reference to the current layer,
-    /// returning the result (or an error if the subscriber no longer exists).
-    pub fn with_current<T>(&self, f: impl FnOnce(&L) -> T) -> Result<T, Error> {
-        let inner = self.inner.upgrade().ok_or(Error {
-            kind: ErrorKind::SubscriberGone,
-        })?;
-        let inner = try_lock!(inner.read(), else return Err(Error::poisoned()));
-        Ok(f(&*inner))
-    }
-}
-
-impl<L, S> Clone for Handle<L, S> {
-    fn clone(&self) -> Self {
-        Handle {
-            inner: self.inner.clone(),
-            _s: PhantomData,
-        }
-    }
-}
-
-// ===== impl Error =====
-
-impl Error {
-    fn poisoned() -> Self {
-        Self {
-            kind: ErrorKind::Poisoned,
-        }
-    }
-
-    /// Returns `true` if this error occurred because the layer was poisoned by
-    /// a panic on another thread.
-    pub fn is_poisoned(&self) -> bool {
-        matches!(self.kind, ErrorKind::Poisoned)
-    }
-
-    /// Returns `true` if this error occurred because the `Subscriber`
-    /// containing the reloadable layer was dropped.
-    pub fn is_dropped(&self) -> bool {
-        matches!(self.kind, ErrorKind::SubscriberGone)
-    }
-}
-
-impl fmt::Display for Error {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        let msg = match self.kind {
-            ErrorKind::SubscriberGone => "subscriber no longer exists",
-            ErrorKind::Poisoned => "lock poisoned",
-        };
-        f.pad(msg)
-    }
-}
-
-impl error::Error for Error {}
diff --git a/vendor/tracing-subscriber-0.3.3/src/field/debug.rs b/vendor/tracing-subscriber/src/field/debug.rs
index cc67d29fe..cc67d29fe 100644
--- a/vendor/tracing-subscriber-0.3.3/src/field/debug.rs
+++ b/vendor/tracing-subscriber/src/field/debug.rs
diff --git a/vendor/tracing-subscriber-0.3.3/src/field/delimited.rs b/vendor/tracing-subscriber/src/field/delimited.rs
index 8c78c4b20..98634cea9 100644
--- a/vendor/tracing-subscriber-0.3.3/src/field/delimited.rs
+++ b/vendor/tracing-subscriber/src/field/delimited.rs
@@ -41,7 +41,7 @@ impl<D, V> Delimited<D, V> {
     /// Returns a new [`MakeVisitor`] implementation that wraps `inner` so that
     /// it will format each visited field separated by the provided `delimiter`.
     ///
-    /// [`MakeVisitor`]: ../trait.MakeVisitor.html
+    /// [`MakeVisitor`]: super::MakeVisitor
     pub fn new(delimiter: D, inner: V) -> Self {
         Self { delimiter, inner }
     }
@@ -53,7 +53,7 @@ impl<D, V> VisitDelimited<D, V> {
     /// Returns a new [`Visit`] implementation that wraps `inner` so that
     /// each formatted field is separated by the provided `delimiter`.
     ///
-    /// [`Visit`]: https://docs.rs/tracing-core/0.1.6/tracing_core/field/trait.Visit.html
+    /// [`Visit`]: tracing_core::field::Visit
     pub fn new(delimiter: D, inner: V) -> Self {
         Self {
             delimiter,
diff --git a/vendor/tracing-subscriber-0.3.3/src/field/display.rs b/vendor/tracing-subscriber/src/field/display.rs
index e0bbc55ed..78a039ce1 100644
--- a/vendor/tracing-subscriber-0.3.3/src/field/display.rs
+++ b/vendor/tracing-subscriber/src/field/display.rs
@@ -18,7 +18,7 @@ impl<V> Messages<V> {
     /// Returns a new [`MakeVisitor`] implementation that will wrap `inner` so
     /// that any strings named `message` are formatted using `fmt::Display`.
     ///
-    /// [`MakeVisitor`]: ../trait.MakeVisitor.html
+    /// [`MakeVisitor`]: super::MakeVisitor
     pub fn new(inner: V) -> Self {
         Messages(inner)
     }
diff --git a/vendor/tracing-subscriber-0.3.3/src/field/mod.rs b/vendor/tracing-subscriber/src/field/mod.rs
index f7d03f2cc..5dfddb362 100644
--- a/vendor/tracing-subscriber-0.3.3/src/field/mod.rs
+++ b/vendor/tracing-subscriber/src/field/mod.rs
@@ -22,7 +22,7 @@ pub mod display;
 /// data to, configuration variables that determine the visitor's behavior, or
 /// `()` when no input is required to produce a visitor.
 ///
-/// [visitors]: https://docs.rs/tracing-core/latest/tracing_core/field/trait.Visit.html
+/// [visitors]: tracing_core::field::Visit
 pub trait MakeVisitor<T> {
     /// The visitor type produced by this `MakeVisitor`.
     type Visitor: Visit;
@@ -33,7 +33,7 @@ pub trait MakeVisitor<T> {
 
 /// A [visitor] that produces output once it has visited a set of fields.
 ///
-/// [visitor]: https://docs.rs/tracing-core/latest/tracing_core/field/trait.Visit.html
+/// [visitor]: tracing_core::field::Visit
 pub trait VisitOutput<Out>: Visit {
     /// Completes the visitor, returning any output.
     ///
@@ -82,10 +82,10 @@ pub trait VisitOutput<Out>: Visit {
 ///     r.record(&mut visitor);
 /// }
 /// ```
-/// [visitor]: https://docs.rs/tracing-core/latest/tracing_core/field/trait.Visit.html
-/// [attr]: https://docs.rs/tracing-core/latest/tracing_core/span/struct.Attributes.html
-/// [rec]: https://docs.rs/tracing-core/latest/tracing_core/span/struct.Record.html
-/// [event]: https://docs.rs/tracing-core/latest/tracing_core/event/struct.Event.html
+/// [visitor]: tracing_core::field::Visit
+/// [attr]: tracing_core::span::Attributes
+/// [rec]: tracing_core::span::Record
+/// [event]: tracing_core::event::Event
 pub trait RecordFields: crate::sealed::Sealed<RecordFieldsMarker> {
     /// Record all the fields in `self` with the provided `visitor`.
     fn record(&self, visitor: &mut dyn Visit);
@@ -341,7 +341,7 @@ pub(in crate::field) mod test_util {
 
     impl<'a> Visit for DebugVisitor<'a> {
         fn record_debug(&mut self, field: &Field, value: &dyn fmt::Debug) {
-            write!(&mut self.writer, "{}={:?}", field, value).unwrap();
+            write!(self.writer, "{}={:?}", field, value).unwrap();
         }
     }
 
diff --git a/vendor/tracing-subscriber-0.3.3/src/filter/directive.rs b/vendor/tracing-subscriber/src/filter/directive.rs
index dd6b063c4..2ae3f0f24 100644
--- a/vendor/tracing-subscriber-0.3.3/src/filter/directive.rs
+++ b/vendor/tracing-subscriber/src/filter/directive.rs
@@ -5,7 +5,7 @@ use alloc::vec;
 use alloc::{string::String, vec::Vec};
 
 use core::{cmp::Ordering, fmt, iter::FromIterator, slice, str::FromStr};
-use tracing_core::Metadata;
+use tracing_core::{Level, Metadata};
 /// Indicates that a string could not be parsed as a filtering directive.
 #[derive(Debug)]
 pub struct ParseError {
@@ -142,6 +142,22 @@ impl DirectiveSet<StaticDirective> {
             None => false,
         }
     }
+
+    /// Same as `enabled` above, but skips `Directive`'s with fields.
+    pub(crate) fn target_enabled(&self, target: &str, level: &Level) -> bool {
+        match self.directives_for_target(target).next() {
+            Some(d) => d.level >= *level,
+            None => false,
+        }
+    }
+
+    pub(crate) fn directives_for_target<'a>(
+        &'a self,
+        target: &'a str,
+    ) -> impl Iterator<Item = &'a StaticDirective> + 'a {
+        self.directives()
+            .filter(move |d| d.cares_about_target(target))
+    }
 }
 
 // === impl StaticDirective ===
@@ -158,6 +174,22 @@ impl StaticDirective {
             level,
         }
     }
+
+    pub(in crate::filter) fn cares_about_target(&self, to_check: &str) -> bool {
+        // Does this directive have a target filter, and does it match the
+        // metadata's target?
+        if let Some(ref target) = self.target {
+            if !to_check.starts_with(&target[..]) {
+                return false;
+            }
+        }
+
+        if !self.field_names.is_empty() {
+            return false;
+        }
+
+        true
+    }
 }
 
 impl Ord for StaticDirective {
diff --git a/vendor/tracing-subscriber-0.3.3/src/filter/env/directive.rs b/vendor/tracing-subscriber/src/filter/env/directive.rs
index 66ca23dc4..f062e6ef9 100644
--- a/vendor/tracing-subscriber-0.3.3/src/filter/env/directive.rs
+++ b/vendor/tracing-subscriber/src/filter/env/directive.rs
@@ -4,14 +4,14 @@ use crate::filter::{
     env::{field, FieldMap},
     level::LevelFilter,
 };
-use lazy_static::lazy_static;
+use once_cell::sync::Lazy;
 use regex::Regex;
 use std::{cmp::Ordering, fmt, iter::FromIterator, str::FromStr};
 use tracing_core::{span, Level, Metadata};
 
 /// A single filtering directive.
 // TODO(eliza): add a builder for programmatically constructing directives?
-#[derive(Debug, Eq, PartialEq)]
+#[derive(Clone, Debug, Eq, PartialEq)]
 #[cfg_attr(docsrs, doc(cfg(feature = "env-filter")))]
 pub struct Directive {
     in_span: Option<String>,
@@ -107,80 +107,52 @@ impl Directive {
             .collect();
         (Dynamics::from_iter(dyns), statics)
     }
-}
-
-impl Match for Directive {
-    fn cares_about(&self, meta: &Metadata<'_>) -> bool {
-        // Does this directive have a target filter, and does it match the
-        // metadata's target?
-        if let Some(ref target) = self.target {
-            if !meta.target().starts_with(&target[..]) {
-                return false;
-            }
-        }
-
-        // Do we have a name filter, and does it match the metadata's name?
-        // TODO(eliza): put name globbing here?
-        if let Some(ref name) = self.in_span {
-            if name != meta.name() {
-                return false;
-            }
-        }
 
-        // Does the metadata define all the fields that this directive cares about?
-        let fields = meta.fields();
-        for field in &self.fields {
-            if fields.field(&field.name).is_none() {
-                return false;
+    pub(super) fn deregexify(&mut self) {
+        for field in &mut self.fields {
+            field.value = match field.value.take() {
+                Some(field::ValueMatch::Pat(pat)) => {
+                    Some(field::ValueMatch::Debug(pat.into_debug_match()))
+                }
+                x => x,
             }
         }
-
-        true
-    }
-
-    fn level(&self) -> &LevelFilter {
-        &self.level
     }
-}
 
-impl FromStr for Directive {
-    type Err = ParseError;
-    fn from_str(from: &str) -> Result<Self, Self::Err> {
-        lazy_static! {
-            static ref DIRECTIVE_RE: Regex = Regex::new(
-                r"(?x)
-                ^(?P<global_level>(?i:trace|debug|info|warn|error|off|[0-5]))$ |
-                 #                 ^^^.
-                 #                     `note: we match log level names case-insensitively
-                ^
-                (?: # target name or span name
-                    (?P<target>[\w:-]+)|(?P<span>\[[^\]]*\])
-                ){1,2}
-                (?: # level or nothing
-                    =(?P<level>(?i:trace|debug|info|warn|error|off|[0-5]))?
-                     #          ^^^.
-                     #              `note: we match log level names case-insensitively
-                )?
-                $
-                "
-            )
-            .unwrap();
-            static ref SPAN_PART_RE: Regex =
-                Regex::new(r#"(?P<name>[^\]\{]+)?(?:\{(?P<fields>[^\}]*)\})?"#).unwrap();
-            static ref FIELD_FILTER_RE: Regex =
-                // TODO(eliza): this doesn't _currently_ handle value matchers that include comma
-                // characters. We should fix that.
-                Regex::new(r#"(?x)
-                    (
-                        # field name
-                        [[:word:]][[[:word:]]\.]*
-                        # value part (optional)
-                        (?:=[^,]+)?
-                    )
-                    # trailing comma or EOS
-                    (?:,\s?|$)
-                "#).unwrap();
-        }
+    pub(super) fn parse(from: &str, regex: bool) -> Result<Self, ParseError> {
+        static DIRECTIVE_RE: Lazy<Regex> = Lazy::new(|| Regex::new(
+            r"(?x)
+            ^(?P<global_level>(?i:trace|debug|info|warn|error|off|[0-5]))$ |
+                #                 ^^^.
+                #                     `note: we match log level names case-insensitively
+            ^
+            (?: # target name or span name
+                (?P<target>[\w:-]+)|(?P<span>\[[^\]]*\])
+            ){1,2}
+            (?: # level or nothing
+                =(?P<level>(?i:trace|debug|info|warn|error|off|[0-5]))?
+                    #          ^^^.
+                    #              `note: we match log level names case-insensitively
+            )?
+            $
+            "
+        )
+        .unwrap());
+        static SPAN_PART_RE: Lazy<Regex> =
+            Lazy::new(|| Regex::new(r#"(?P<name>[^\]\{]+)?(?:\{(?P<fields>[^\}]*)\})?"#).unwrap());
+        static FIELD_FILTER_RE: Lazy<Regex> =
+            // TODO(eliza): this doesn't _currently_ handle value matchers that include comma
+            // characters. We should fix that.
+            Lazy::new(|| Regex::new(r#"(?x)
+                (
+                    # field name
+                    [[:word:]][[[:word:]]\.]*
+                    # value part (optional)
+                    (?:=[^,]+)?
+                )
+                # trailing comma or EOS
+                (?:,\s?|$)
+            "#).unwrap());
 
         let caps = DIRECTIVE_RE.captures(from).ok_or_else(ParseError::new)?;
 
@@ -214,7 +186,7 @@ impl FromStr for Directive {
                     .map(|c| {
                         FIELD_FILTER_RE
                             .find_iter(c.as_str())
-                            .map(|c| c.as_str().parse())
+                            .map(|c| field::Match::parse(c.as_str(), regex))
                             .collect::<Result<Vec<_>, _>>()
                     })
                     .unwrap_or_else(|| Ok(Vec::new()));
@@ -228,7 +200,7 @@ impl FromStr for Directive {
             // Setting the target without the level enables every level for that target
             .unwrap_or(LevelFilter::TRACE);
 
-        Ok(Directive {
+        Ok(Self {
             level,
             target,
             in_span,
@@ -237,6 +209,48 @@ impl FromStr for Directive {
     }
 }
 
+impl Match for Directive {
+    fn cares_about(&self, meta: &Metadata<'_>) -> bool {
+        // Does this directive have a target filter, and does it match the
+        // metadata's target?
+        if let Some(ref target) = self.target {
+            if !meta.target().starts_with(&target[..]) {
+                return false;
+            }
+        }
+
+        // Do we have a name filter, and does it match the metadata's name?
+        // TODO(eliza): put name globbing here?
+        if let Some(ref name) = self.in_span {
+            if name != meta.name() {
+                return false;
+            }
+        }
+
+        // Does the metadata define all the fields that this directive cares about?
+        let actual_fields = meta.fields();
+        for expected_field in &self.fields {
+            // Does the actual field set (from the metadata) contain this field?
+            if actual_fields.field(&expected_field.name).is_none() {
+                return false;
+            }
+        }
+
+        true
+    }
+
+    fn level(&self) -> &LevelFilter {
+        &self.level
+    }
+}
+
+impl FromStr for Directive {
+    type Err = ParseError;
+    fn from_str(from: &str) -> Result<Self, Self::Err> {
+        Directive::parse(from, true)
+    }
+}
+
 impl Default for Directive {
     fn default() -> Self {
         Directive {
diff --git a/vendor/tracing-subscriber-0.3.3/src/filter/env/field.rs b/vendor/tracing-subscriber/src/filter/env/field.rs
index 970850f92..1394fd04a 100644
--- a/vendor/tracing-subscriber-0.3.3/src/filter/env/field.rs
+++ b/vendor/tracing-subscriber/src/filter/env/field.rs
@@ -2,7 +2,7 @@ use matchers::Pattern;
 use std::{
     cmp::Ordering,
     error::Error,
-    fmt,
+    fmt::{self, Write},
     str::FromStr,
     sync::{
         atomic::{AtomicBool, Ordering::*},
@@ -13,7 +13,7 @@ use std::{
 use super::{FieldMap, LevelFilter};
 use tracing_core::field::{Field, Visit};
 
-#[derive(Debug, Eq, PartialEq)]
+#[derive(Clone, Debug, Eq, PartialEq)]
 pub(crate) struct Match {
     pub(crate) name: String, // TODO: allow match patterns for names?
     pub(crate) value: Option<ValueMatch>,
@@ -38,11 +38,20 @@ pub(crate) struct MatchVisitor<'a> {
 
 #[derive(Debug, Clone)]
 pub(crate) enum ValueMatch {
+    /// Matches a specific `bool` value.
     Bool(bool),
+    /// Matches a specific `f64` value.
     F64(f64),
+    /// Matches a specific `u64` value.
     U64(u64),
+    /// Matches a specific `i64` value.
     I64(i64),
+    /// Matches any `NaN` `f64` value.
     NaN,
+    /// Matches any field whose `fmt::Debug` output is equal to a fixed string.
+    Debug(MatchDebug),
+    /// Matches any field whose `fmt::Debug` output matches a regular expression
+    /// pattern.
     Pat(Box<MatchPattern>),
 }
 
@@ -97,6 +106,9 @@ impl Ord for ValueMatch {
 
             (Pat(this), Pat(that)) => this.cmp(that),
             (Pat(_), _) => Ordering::Greater,
+
+            (Debug(this), Debug(that)) => this.cmp(that),
+            (Debug(_), _) => Ordering::Greater,
         }
     }
 }
@@ -107,12 +119,25 @@ impl PartialOrd for ValueMatch {
     }
 }
 
+/// Matches a field's `fmt::Debug` output against a regular expression pattern.
+///
+/// This is used for matching all non-literal field value filters when regular
+/// expressions are enabled.
 #[derive(Debug, Clone)]
 pub(crate) struct MatchPattern {
     pub(crate) matcher: Pattern,
     pattern: Arc<str>,
 }
 
+/// Matches a field's `fmt::Debug` output against a fixed string pattern.
+///
+/// This is used for matching all non-literal field value filters when regular
+/// expressions are disabled.
+#[derive(Debug, Clone)]
+pub(crate) struct MatchDebug {
+    pattern: Arc<str>,
+}
+
 /// Indicates that a field name specified in a filter directive was invalid.
 #[derive(Clone, Debug)]
 #[cfg_attr(docsrs, doc(cfg(feature = "env-filter")))]
@@ -122,9 +147,17 @@ pub struct BadName {
 
 // === impl Match ===
 
-impl FromStr for Match {
-    type Err = Box<dyn Error + Send + Sync>;
-    fn from_str(s: &str) -> Result<Self, Self::Err> {
+impl Match {
+    pub(crate) fn has_value(&self) -> bool {
+        self.value.is_some()
+    }
+
+    // TODO: reference count these strings?
+    pub(crate) fn name(&self) -> String {
+        self.name.clone()
+    }
+
+    pub(crate) fn parse(s: &str, regex: bool) -> Result<Self, Box<dyn Error + Send + Sync>> {
         let mut parts = s.split('=');
         let name = parts
             .next()
@@ -133,22 +166,17 @@ impl FromStr for Match {
             })?
             // TODO: validate field name
             .to_string();
-        let value = parts.next().map(ValueMatch::from_str).transpose()?;
+        let value = parts
+            .next()
+            .map(|part| match regex {
+                true => ValueMatch::parse_regex(part),
+                false => Ok(ValueMatch::parse_non_regex(part)),
+            })
+            .transpose()?;
         Ok(Match { name, value })
     }
 }
 
-impl Match {
-    pub(crate) fn has_value(&self) -> bool {
-        self.value.is_some()
-    }
-
-    // TODO: reference count these strings?
-    pub(crate) fn name(&self) -> String {
-        self.name.clone()
-    }
-}
-
 impl fmt::Display for Match {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         fmt::Display::fmt(&self.name, f)?;
@@ -199,9 +227,14 @@ fn value_match_f64(v: f64) -> ValueMatch {
     }
 }
 
-impl FromStr for ValueMatch {
-    type Err = matchers::Error;
-    fn from_str(s: &str) -> Result<Self, Self::Err> {
+impl ValueMatch {
+    /// Parse a `ValueMatch` that will match `fmt::Debug` fields using regular
+    /// expressions.
+    ///
+    /// This returns an error if the string didn't contain a valid `bool`,
+    /// `u64`, `i64`, or `f64` literal, and couldn't be parsed as a regular
+    /// expression.
+    fn parse_regex(s: &str) -> Result<Self, matchers::Error> {
         s.parse::<bool>()
             .map(ValueMatch::Bool)
             .or_else(|_| s.parse::<u64>().map(ValueMatch::U64))
@@ -212,6 +245,21 @@ impl FromStr for ValueMatch {
                     .map(|p| ValueMatch::Pat(Box::new(p)))
             })
     }
+
+    /// Parse a `ValueMatch` that will match `fmt::Debug` against a fixed
+    /// string.
+    ///
+    /// This does *not* return an error, because any string that isn't a valid
+    /// `bool`, `u64`, `i64`, or `f64` literal is treated as expected
+    /// `fmt::Debug` output.
+    fn parse_non_regex(s: &str) -> Self {
+        s.parse::<bool>()
+            .map(ValueMatch::Bool)
+            .or_else(|_| s.parse::<u64>().map(ValueMatch::U64))
+            .or_else(|_| s.parse::<i64>().map(ValueMatch::I64))
+            .or_else(|_| s.parse::<f64>().map(value_match_f64))
+            .unwrap_or_else(|_| ValueMatch::Debug(MatchDebug::new(s)))
+    }
 }
 
 impl fmt::Display for ValueMatch {
@@ -222,6 +270,7 @@ impl fmt::Display for ValueMatch {
             ValueMatch::NaN => fmt::Display::fmt(&std::f64::NAN, f),
             ValueMatch::I64(ref inner) => fmt::Display::fmt(inner, f),
             ValueMatch::U64(ref inner) => fmt::Display::fmt(inner, f),
+            ValueMatch::Debug(ref inner) => fmt::Display::fmt(inner, f),
             ValueMatch::Pat(ref inner) => fmt::Display::fmt(inner, f),
         }
     }
@@ -264,6 +313,12 @@ impl MatchPattern {
     fn debug_matches(&self, d: &impl fmt::Debug) -> bool {
         self.matcher.debug_matches(d)
     }
+
+    pub(super) fn into_debug_match(self) -> MatchDebug {
+        MatchDebug {
+            pattern: self.pattern,
+        }
+    }
 }
 
 impl PartialEq for MatchPattern {
@@ -289,6 +344,102 @@ impl Ord for MatchPattern {
     }
 }
 
+// === impl MatchDebug ===
+
+impl MatchDebug {
+    fn new(s: &str) -> Self {
+        Self {
+            pattern: s.to_owned().into(),
+        }
+    }
+
+    #[inline]
+    fn debug_matches(&self, d: &impl fmt::Debug) -> bool {
+        // Naively, we would probably match a value's `fmt::Debug` output by
+        // formatting it to a string, and then checking if the string is equal
+        // to the expected pattern. However, this would require allocating every
+        // time we want to match a field value against a `Debug` matcher, which
+        // can be avoided.
+        //
+        // Instead, we implement `fmt::Write` for a type that, rather than
+        // actually _writing_ the strings to something, matches them against the
+        // expected pattern, and returns an error if the pattern does not match.
+        struct Matcher<'a> {
+            pattern: &'a str,
+        }
+
+        impl fmt::Write for Matcher<'_> {
+            fn write_str(&mut self, s: &str) -> fmt::Result {
+                // If the string is longer than the remaining expected string,
+                // we know it won't match, so bail.
+                if s.len() > self.pattern.len() {
+                    return Err(fmt::Error);
+                }
+
+                // If the expected string begins with the string that was
+                // written, we are still potentially a match. Advance the
+                // position in the expected pattern to chop off the matched
+                // output, and continue.
+                if self.pattern.starts_with(s) {
+                    self.pattern = &self.pattern[s.len()..];
+                    return Ok(());
+                }
+
+                // Otherwise, the expected string doesn't include the string
+                // that was written at the current position, so the `fmt::Debug`
+                // output doesn't match! Return an error signalling that this
+                // doesn't match.
+                Err(fmt::Error)
+            }
+        }
+        let mut matcher = Matcher {
+            pattern: &self.pattern,
+        };
+
+        // Try to "write" the value's `fmt::Debug` output to a `Matcher`. This
+        // returns an error if the `fmt::Debug` implementation wrote any
+        // characters that did not match the expected pattern.
+        write!(matcher, "{:?}", d).is_ok()
+    }
+}
+
+impl fmt::Display for MatchDebug {
+    #[inline]
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        fmt::Display::fmt(&*self.pattern, f)
+    }
+}
+
+impl AsRef<str> for MatchDebug {
+    #[inline]
+    fn as_ref(&self) -> &str {
+        self.pattern.as_ref()
+    }
+}
+
+impl PartialEq for MatchDebug {
+    #[inline]
+    fn eq(&self, other: &Self) -> bool {
+        self.pattern == other.pattern
+    }
+}
+
+impl Eq for MatchDebug {}
+
+impl PartialOrd for MatchDebug {
+    #[inline]
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+        Some(self.pattern.cmp(&other.pattern))
+    }
+}
+
+impl Ord for MatchDebug {
+    #[inline]
+    fn cmp(&self, other: &Self) -> Ordering {
+        self.pattern.cmp(&other.pattern)
+    }
+}
+
 // === impl BadName ===
 
 impl Error for BadName {}
@@ -401,6 +552,9 @@ impl<'a> Visit for MatchVisitor<'a> {
             Some((ValueMatch::Pat(ref e), ref matched)) if e.str_matches(&value) => {
                 matched.store(true, Release);
             }
+            Some((ValueMatch::Debug(ref e), ref matched)) if e.debug_matches(&value) => {
+                matched.store(true, Release)
+            }
             _ => {}
         }
     }
@@ -410,7 +564,63 @@ impl<'a> Visit for MatchVisitor<'a> {
             Some((ValueMatch::Pat(ref e), ref matched)) if e.debug_matches(&value) => {
                 matched.store(true, Release);
             }
+            Some((ValueMatch::Debug(ref e), ref matched)) if e.debug_matches(&value) => {
+                matched.store(true, Release)
+            }
             _ => {}
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[derive(Debug)]
+    #[allow(dead_code)]
+    struct MyStruct {
+        answer: usize,
+        question: &'static str,
+    }
+
+    #[test]
+    fn debug_struct_match() {
+        let my_struct = MyStruct {
+            answer: 42,
+            question: "life, the universe, and everything",
+        };
+
+        let pattern = "MyStruct { answer: 42, question: \"life, the universe, and everything\" }";
+
+        assert_eq!(
+            format!("{:?}", my_struct),
+            pattern,
+            "`MyStruct`'s `Debug` impl doesn't output the expected string"
+        );
+
+        let matcher = MatchDebug {
+            pattern: pattern.into(),
+        };
+        assert!(matcher.debug_matches(&my_struct))
+    }
+
+    #[test]
+    fn debug_struct_not_match() {
+        let my_struct = MyStruct {
+            answer: 42,
+            question: "what shall we have for lunch?",
+        };
+
+        let pattern = "MyStruct { answer: 42, question: \"life, the universe, and everything\" }";
+
+        assert_eq!(
+            format!("{:?}", my_struct),
+            "MyStruct { answer: 42, question: \"what shall we have for lunch?\" }",
+            "`MyStruct`'s `Debug` impl doesn't output the expected string"
+        );
+
+        let matcher = MatchDebug {
+            pattern: pattern.into(),
+        };
+        assert!(!matcher.debug_matches(&my_struct))
+    }
+}
diff --git a/vendor/tracing-subscriber-0.3.3/src/filter/env/mod.rs b/vendor/tracing-subscriber/src/filter/env/mod.rs
index 81fe0e62d..81a9ae2bd 100644
--- a/vendor/tracing-subscriber-0.3.3/src/filter/env/mod.rs
+++ b/vendor/tracing-subscriber/src/filter/env/mod.rs
@@ -4,7 +4,8 @@
 // these are publicly re-exported, but the compiler doesn't realize
 // that for some reason.
 #[allow(unreachable_pub)]
-pub use self::{directive::Directive, field::BadName as BadFieldName};
+pub use self::{builder::Builder, directive::Directive, field::BadName as BadFieldName};
+mod builder;
 mod directive;
 mod field;
 
@@ -15,6 +16,7 @@ use crate::{
 };
 use directive::ParseError;
 use std::{cell::RefCell, collections::HashMap, env, error::Error, fmt, str::FromStr};
+use thread_local::ThreadLocal;
 use tracing_core::{
     callsite,
     field::Field,
@@ -26,6 +28,16 @@ use tracing_core::{
 /// A [`Layer`] which filters spans and events based on a set of filter
 /// directives.
 ///
+/// `EnvFilter` implements both the [`Layer`](#impl-Layer<S>) and [`Filter`] traits, so it may
+/// be used for both [global filtering][global] and [per-layer filtering][plf],
+/// respectively. See [the documentation on filtering with `Layer`s][filtering]
+/// for details.
+///
+/// The [`Targets`] type implements a similar form of filtering, but without the
+/// ability to dynamically enable events based on the current span context, and
+/// without filtering on field values. When these features are not required,
+/// [`Targets`] provides a lighter-weight alternative to [`EnvFilter`].
+///
 /// # Directives
 ///
 /// A filter consists of one or more comma-separated directives which match on [`Span`]s and [`Event`]s.
@@ -52,10 +64,27 @@ use tracing_core::{
 ///    and will match on any [`Span`] or [`Event`] that has a field with that name.
 ///    For example: `[span{field=\"value\"}]=debug`, `[{field}]=trace`.
 /// - `value` matches on the value of a span's field. If a value is a numeric literal or a bool,
-///    it will match _only_ on that value. Otherwise, this filter acts as a regex on
-///    the `std::fmt::Debug` output from the value.
+///    it will match _only_ on that value. Otherwise, this filter matches the
+///    [`std::fmt::Debug`] output from the value.
 /// - `level` sets a maximum verbosity level accepted by this directive.
 ///
+/// When a field value directive (`[{<FIELD NAME>=<FIELD_VALUE>}]=...`) matches a
+/// value's [`std::fmt::Debug`] output (i.e., the field value in the directive
+/// is not a `bool`, `i64`, `u64`, or `f64` literal), the matched pattern may be
+/// interpreted as either a regular expression or as the precise expected
+/// output of the field's [`std::fmt::Debug`] implementation. By default, these
+/// filters are interpreted as regular expressions, but this can be disabled
+/// using the [`Builder::with_regex`] builder method to use precise matching
+/// instead.
+///
+/// When field value filters are interpreted as regular expressions, the
+/// [`regex-automata` crate's regular expression syntax][re-syntax] is
+/// supported.
+///
+/// **Note**: When filters are constructed from potentially untrusted inputs,
+/// [disabling regular expression matching](Builder::with_regex) is strongly
+/// recommended.
+///
 /// ## Usage Notes
 ///
 /// - The portion of the directive which is included within the square brackets is `tracing`-specific.
@@ -72,7 +101,7 @@ use tracing_core::{
 /// - A dash in a target will only appear when being specified explicitly:
 ///   `tracing::info!(target: "target-name", ...);`
 ///
-/// ## Examples
+/// ## Example Syntax
 ///
 /// - `tokio::net=info` will enable all spans or events that:
 ///    - have the `tokio::net` target,
@@ -89,10 +118,68 @@ use tracing_core::{
 ///    - which has a field named `name` with value `bob`,
 ///    - at _any_ level.
 ///
-/// The [`Targets`] type implements a similar form of filtering, but without the
-/// ability to dynamically enable events based on the current span context, and
-/// without filtering on field values. When these features are not required,
-/// [`Targets`] provides a lighter-weight alternative to [`EnvFilter`].
+/// # Examples
+///
+/// Parsing an `EnvFilter` from the [default environment
+/// variable](EnvFilter::from_default_env) (`RUST_LOG`):
+///
+/// ```
+/// use tracing_subscriber::{EnvFilter, fmt, prelude::*};
+///
+/// tracing_subscriber::registry()
+///     .with(fmt::layer())
+///     .with(EnvFilter::from_default_env())
+///     .init();
+/// ```
+///
+/// Parsing an `EnvFilter` [from a user-provided environment
+/// variable](EnvFilter::from_env):
+///
+/// ```
+/// use tracing_subscriber::{EnvFilter, fmt, prelude::*};
+///
+/// tracing_subscriber::registry()
+///     .with(fmt::layer())
+///     .with(EnvFilter::from_env("MYAPP_LOG"))
+///     .init();
+/// ```
+///
+/// Using `EnvFilter` as a [per-layer filter][plf] to filter only a single
+/// [`Layer`]:
+///
+/// ```
+/// use tracing_subscriber::{EnvFilter, fmt, prelude::*};
+///
+/// // Parse an `EnvFilter` configuration from the `RUST_LOG`
+/// // environment variable.
+/// let filter = EnvFilter::from_default_env();
+///
+/// // Apply the filter to this layer *only*.
+/// let filtered_layer = fmt::layer().with_filter(filter);
+///
+/// // Some other layer, whose output we don't want to filter.
+/// let unfiltered_layer = // ...
+///     # fmt::layer();
+///
+/// tracing_subscriber::registry()
+///     .with(filtered_layer)
+///     .with(unfiltered_layer)
+///     .init();
+/// ```
+/// # Constructing `EnvFilter`s
+///
+/// An `EnvFilter` is be constructed by parsing a string containing one or more
+/// directives. The [`EnvFilter::new`] constructor parses an `EnvFilter` from a
+/// string, ignoring any invalid directives, while [`EnvFilter::try_new`]
+/// returns an error if invalid directives are encountered. Similarly, the
+/// [`EnvFilter::from_env`] and [`EnvFilter::try_from_env`] constructors parse
+/// an `EnvFilter` from the value of the provided environment variable, with
+/// lossy and strict validation, respectively.
+///
+/// A [builder](EnvFilter::builder) interface is available to set additional
+/// configuration options prior to parsing an `EnvFilter`. See the [`Builder`
+/// type's documentation](Builder) for details on the options that can be
+/// configured using the builder.
 ///
 /// [`Span`]: tracing_core::span
 /// [fields]: tracing_core::Field
@@ -100,6 +187,11 @@ use tracing_core::{
 /// [`level`]: tracing_core::Level
 /// [`Metadata`]: tracing_core::Metadata
 /// [`Targets`]: crate::filter::Targets
+/// [`env_logger`]: https://crates.io/crates/env_logger
+/// [`Filter`]: #impl-Filter<S>
+/// [global]: crate::layer#global-filtering
+/// [plf]: crate::layer#per-layer-filtering
+/// [filtering]: crate::layer#filtering-with-layers
 #[cfg_attr(docsrs, doc(cfg(all(feature = "env-filter", feature = "std"))))]
 #[derive(Debug)]
 pub struct EnvFilter {
@@ -108,10 +200,8 @@ pub struct EnvFilter {
     has_dynamics: bool,
     by_id: RwLock<HashMap<span::Id, directive::SpanMatcher>>,
     by_cs: RwLock<HashMap<callsite::Identifier, directive::CallsiteMatcher>>,
-}
-
-thread_local! {
-    static SCOPE: RefCell<Vec<LevelFilter>> = RefCell::new(Vec::new());
+    scope: ThreadLocal<RefCell<Vec<LevelFilter>>>,
+    regex: bool,
 }
 
 type FieldMap<T> = HashMap<Field, T>;
@@ -134,58 +224,181 @@ impl EnvFilter {
     /// `RUST_LOG` is the default environment variable used by
     /// [`EnvFilter::from_default_env`] and [`EnvFilter::try_from_default_env`].
     ///
-    /// [`EnvFilter::from_default_env`]: #method.from_default_env
-    /// [`EnvFilter::try_from_default_env`]: #method.try_from_default_env
+    /// [`EnvFilter::from_default_env`]: EnvFilter::from_default_env()
+    /// [`EnvFilter::try_from_default_env`]: EnvFilter::try_from_default_env()
     pub const DEFAULT_ENV: &'static str = "RUST_LOG";
 
+    // === constructors, etc ===
+
+    /// Returns a [builder] that can be used to configure a new [`EnvFilter`]
+    /// instance.
+    ///
+    /// The [`Builder`] type is used to set additional configurations, such as
+    /// [whether regular expressions are enabled](Builder::with_regex) or [the
+    /// default directive](Builder::with_default_directive) before parsing an
+    /// [`EnvFilter`] from a string or environment variable.
+    ///
+    /// [builder]: https://rust-unofficial.github.io/patterns/patterns/creational/builder.html
+    pub fn builder() -> Builder {
+        Builder::default()
+    }
+
     /// Returns a new `EnvFilter` from the value of the `RUST_LOG` environment
     /// variable, ignoring any invalid filter directives.
+    ///
+    /// If the environment variable is empty or not set, or if it contains only
+    /// invalid directives, a default directive enabling the [`ERROR`] level is
+    /// added.
+    ///
+    /// To set additional configuration options prior to parsing the filter, use
+    /// the [`Builder`] type instead.
+    ///
+    /// This function is equivalent to the following:
+    ///
+    /// ```rust
+    /// use tracing_subscriber::filter::{EnvFilter, LevelFilter};
+    ///
+    /// # fn docs() -> EnvFilter {
+    /// EnvFilter::builder()
+    ///     .with_default_directive(LevelFilter::ERROR.into())
+    ///     .from_env_lossy()
+    /// # }
+    /// ```
+    ///
+    /// [`ERROR`]: tracing::Level::ERROR
     pub fn from_default_env() -> Self {
-        Self::from_env(Self::DEFAULT_ENV)
+        Self::builder()
+            .with_default_directive(LevelFilter::ERROR.into())
+            .from_env_lossy()
     }
 
     /// Returns a new `EnvFilter` from the value of the given environment
     /// variable, ignoring any invalid filter directives.
+    ///
+    /// If the environment variable is empty or not set, or if it contains only
+    /// invalid directives, a default directive enabling the [`ERROR`] level is
+    /// added.
+    ///
+    /// To set additional configuration options prior to parsing the filter, use
+    /// the [`Builder`] type instead.
+    ///
+    /// This function is equivalent to the following:
+    ///
+    /// ```rust
+    /// use tracing_subscriber::filter::{EnvFilter, LevelFilter};
+    ///
+    /// # fn docs() -> EnvFilter {
+    /// # let env = "";
+    /// EnvFilter::builder()
+    ///     .with_default_directive(LevelFilter::ERROR.into())
+    ///     .with_env_var(env)
+    ///     .from_env_lossy()
+    /// # }
+    /// ```
+    ///
+    /// [`ERROR`]: tracing::Level::ERROR
     pub fn from_env<A: AsRef<str>>(env: A) -> Self {
-        env::var(env.as_ref()).map(Self::new).unwrap_or_default()
+        Self::builder()
+            .with_default_directive(LevelFilter::ERROR.into())
+            .with_env_var(env.as_ref())
+            .from_env_lossy()
     }
 
     /// Returns a new `EnvFilter` from the directives in the given string,
     /// ignoring any that are invalid.
-    pub fn new<S: AsRef<str>>(dirs: S) -> Self {
-        let directives = dirs.as_ref().split(',').filter_map(|s| match s.parse() {
-            Ok(d) => Some(d),
-            Err(err) => {
-                eprintln!("ignoring `{}`: {}", s, err);
-                None
-            }
-        });
-        Self::from_directives(directives)
+    ///
+    /// If the string is empty or contains only invalid directives, a default
+    /// directive enabling the [`ERROR`] level is added.
+    ///
+    /// To set additional configuration options prior to parsing the filter, use
+    /// the [`Builder`] type instead.
+    ///
+    /// This function is equivalent to the following:
+    ///
+    /// ```rust
+    /// use tracing_subscriber::filter::{EnvFilter, LevelFilter};
+    ///
+    /// # fn docs() -> EnvFilter {
+    /// # let directives = "";
+    /// EnvFilter::builder()
+    ///     .with_default_directive(LevelFilter::ERROR.into())
+    ///     .parse_lossy(directives)
+    /// # }
+    /// ```
+    ///
+    /// [`ERROR`]: tracing::Level::ERROR
+    pub fn new<S: AsRef<str>>(directives: S) -> Self {
+        Self::builder()
+            .with_default_directive(LevelFilter::ERROR.into())
+            .parse_lossy(directives)
     }
 
     /// Returns a new `EnvFilter` from the directives in the given string,
     /// or an error if any are invalid.
+    ///
+    /// If the string is empty, a default directive enabling the [`ERROR`] level
+    /// is added.
+    ///
+    /// To set additional configuration options prior to parsing the filter, use
+    /// the [`Builder`] type instead.
+    ///
+    /// This function is equivalent to the following:
+    ///
+    /// ```rust
+    /// use tracing_subscriber::filter::{EnvFilter, LevelFilter};
+    ///
+    /// # fn docs() -> Result<EnvFilter, tracing_subscriber::filter::ParseError> {
+    /// # let directives = "";
+    /// EnvFilter::builder()
+    ///     .with_default_directive(LevelFilter::ERROR.into())
+    ///     .parse(directives)
+    /// # }
+    /// ```
+    ///
+    /// [`ERROR`]: tracing::Level::ERROR
     pub fn try_new<S: AsRef<str>>(dirs: S) -> Result<Self, directive::ParseError> {
-        let directives = dirs
-            .as_ref()
-            .split(',')
-            .map(|s| s.parse())
-            .collect::<Result<Vec<_>, _>>()?;
-        Ok(Self::from_directives(directives))
+        Self::builder().parse(dirs)
     }
 
     /// Returns a new `EnvFilter` from the value of the `RUST_LOG` environment
-    /// variable, or an error if the environment variable contains any invalid
-    /// filter directives.
+    /// variable, or an error if the environment variable is unset or contains
+    /// any invalid filter directives.
+    ///
+    /// To set additional configuration options prior to parsing the filter, use
+    /// the [`Builder`] type instead.
+    ///
+    /// This function is equivalent to the following:
+    ///
+    /// ```rust
+    /// use tracing_subscriber::EnvFilter;
+    ///
+    /// # fn docs() -> Result<EnvFilter, tracing_subscriber::filter::FromEnvError> {
+    /// EnvFilter::builder().try_from_env()
+    /// # }
+    /// ```
     pub fn try_from_default_env() -> Result<Self, FromEnvError> {
-        Self::try_from_env(Self::DEFAULT_ENV)
+        Self::builder().try_from_env()
     }
 
     /// Returns a new `EnvFilter` from the value of the given environment
     /// variable, or an error if the environment variable is unset or contains
     /// any invalid filter directives.
+    ///
+    /// To set additional configuration options prior to parsing the filter, use
+    /// the [`Builder`] type instead.
+    ///
+    /// This function is equivalent to the following:
+    ///
+    /// ```rust
+    /// use tracing_subscriber::EnvFilter;
+    ///
+    /// # fn docs() -> Result<EnvFilter, tracing_subscriber::filter::FromEnvError> {
+    /// # let env = "";
+    /// EnvFilter::builder().with_env_var(env).try_from_env()
+    /// # }
+    /// ```
     pub fn try_from_env<A: AsRef<str>>(env: A) -> Result<Self, FromEnvError> {
-        env::var(env.as_ref())?.parse().map_err(Into::into)
+        Self::builder().with_env_var(env.as_ref()).try_from_env()
     }
 
     /// Add a filtering directive to this `EnvFilter`.
@@ -202,13 +415,13 @@ impl EnvFilter {
     /// and events as a previous filter, but sets a different level for those
     /// spans and events, the previous directive is overwritten.
     ///
-    /// [`LevelFilter`]: ../filter/struct.LevelFilter.html
-    /// [`Level`]: https://docs.rs/tracing-core/latest/tracing_core/struct.Level.html
+    /// [`LevelFilter`]: super::LevelFilter
+    /// [`Level`]: tracing_core::Level
     ///
     /// # Examples
     ///
     /// From [`LevelFilter`]:
-    ////
+    ///
     /// ```rust
     /// use tracing_subscriber::filter::{EnvFilter, LevelFilter};
     /// let mut filter = EnvFilter::from_default_env()
@@ -223,9 +436,9 @@ impl EnvFilter {
     /// let mut filter = EnvFilter::from_default_env()
     ///     .add_directive(Level::INFO.into());
     /// ```
-    ////
+    ///
     /// Parsed from a string:
-    ////
+    ///
     /// ```rust
     /// use tracing_subscriber::filter::{EnvFilter, Directive};
     ///
@@ -236,7 +449,15 @@ impl EnvFilter {
     /// # Ok(())
     /// # }
     /// ```
-    pub fn add_directive(mut self, directive: Directive) -> Self {
+    /// In the above example, substitute `my_crate`, `module`, etc. with the
+    /// name your target crate/module is imported with. This might be
+    /// different from the package name in Cargo.toml (`-` is replaced by `_`).
+    /// Example, if the package name in your Cargo.toml is `MY-FANCY-LIB`, then
+    /// the corresponding Rust identifier would be `MY_FANCY_LIB`:
+    pub fn add_directive(mut self, mut directive: Directive) -> Self {
+        if !self.regex {
+            directive.deregexify();
+        }
         if let Some(stat) = directive.to_static() {
             self.statics.add(stat)
         } else {
@@ -246,165 +467,19 @@ impl EnvFilter {
         self
     }
 
-    fn from_directives(directives: impl IntoIterator<Item = Directive>) -> Self {
-        use tracing::level_filters::STATIC_MAX_LEVEL;
-        use tracing::Level;
-
-        let directives: Vec<_> = directives.into_iter().collect();
-
-        let disabled: Vec<_> = directives
-            .iter()
-            .filter(|directive| directive.level > STATIC_MAX_LEVEL)
-            .collect();
-
-        if !disabled.is_empty() {
-            #[cfg(feature = "ansi_term")]
-            use ansi_term::{Color, Style};
-            // NOTE: We can't use a configured `MakeWriter` because the EnvFilter
-            // has no knowledge of any underlying subscriber or subscriber, which
-            // may or may not use a `MakeWriter`.
-            let warn = |msg: &str| {
-                #[cfg(not(feature = "ansi_term"))]
-                let msg = format!("warning: {}", msg);
-                #[cfg(feature = "ansi_term")]
-                let msg = {
-                    let bold = Style::new().bold();
-                    let mut warning = Color::Yellow.paint("warning");
-                    warning.style_ref_mut().is_bold = true;
-                    format!("{}{} {}", warning, bold.paint(":"), bold.paint(msg))
-                };
-                eprintln!("{}", msg);
-            };
-            let ctx_prefixed = |prefix: &str, msg: &str| {
-                #[cfg(not(feature = "ansi_term"))]
-                let msg = format!("note: {}", msg);
-                #[cfg(feature = "ansi_term")]
-                let msg = {
-                    let mut equal = Color::Fixed(21).paint("="); // dark blue
-                    equal.style_ref_mut().is_bold = true;
-                    format!(" {} {} {}", equal, Style::new().bold().paint(prefix), msg)
-                };
-                eprintln!("{}", msg);
-            };
-            let ctx_help = |msg| ctx_prefixed("help:", msg);
-            let ctx_note = |msg| ctx_prefixed("note:", msg);
-            let ctx = |msg: &str| {
-                #[cfg(not(feature = "ansi_term"))]
-                let msg = format!("note: {}", msg);
-                #[cfg(feature = "ansi_term")]
-                let msg = {
-                    let mut pipe = Color::Fixed(21).paint("|");
-                    pipe.style_ref_mut().is_bold = true;
-                    format!(" {} {}", pipe, msg)
-                };
-                eprintln!("{}", msg);
-            };
-            warn("some trace filter directives would enable traces that are disabled statically");
-            for directive in disabled {
-                let target = if let Some(target) = &directive.target {
-                    format!("the `{}` target", target)
-                } else {
-                    "all targets".into()
-                };
-                let level = directive
-                    .level
-                    .into_level()
-                    .expect("=off would not have enabled any filters");
-                ctx(&format!(
-                    "`{}` would enable the {} level for {}",
-                    directive, level, target
-                ));
-            }
-            ctx_note(&format!("the static max level is `{}`", STATIC_MAX_LEVEL));
-            let help_msg = || {
-                let (feature, filter) = match STATIC_MAX_LEVEL.into_level() {
-                    Some(Level::TRACE) => unreachable!(
-                        "if the max level is trace, no static filtering features are enabled"
-                    ),
-                    Some(Level::DEBUG) => ("max_level_debug", Level::TRACE),
-                    Some(Level::INFO) => ("max_level_info", Level::DEBUG),
-                    Some(Level::WARN) => ("max_level_warn", Level::INFO),
-                    Some(Level::ERROR) => ("max_level_error", Level::WARN),
-                    None => return ("max_level_off", String::new()),
-                };
-                (feature, format!("{} ", filter))
-            };
-            let (feature, earlier_level) = help_msg();
-            ctx_help(&format!(
-                "to enable {}logging, remove the `{}` feature",
-                earlier_level, feature
-            ));
-        }
-
-        let (dynamics, mut statics) = Directive::make_tables(directives);
-        let has_dynamics = !dynamics.is_empty();
-
-        if statics.is_empty() && !has_dynamics {
-            statics.add(directive::StaticDirective::default());
-        }
-
-        Self {
-            statics,
-            dynamics,
-            has_dynamics,
-            by_id: RwLock::new(HashMap::new()),
-            by_cs: RwLock::new(HashMap::new()),
-        }
-    }
-
-    fn cares_about_span(&self, span: &span::Id) -> bool {
-        let spans = try_lock!(self.by_id.read(), else return false);
-        spans.contains_key(span)
-    }
-
-    fn base_interest(&self) -> Interest {
-        if self.has_dynamics {
-            Interest::sometimes()
-        } else {
-            Interest::never()
-        }
-    }
-}
-
-impl<S: Subscriber> Layer<S> for EnvFilter {
-    fn register_callsite(&self, metadata: &'static Metadata<'static>) -> Interest {
-        if self.has_dynamics && metadata.is_span() {
-            // If this metadata describes a span, first, check if there is a
-            // dynamic filter that should be constructed for it. If so, it
-            // should always be enabled, since it influences filtering.
-            if let Some(matcher) = self.dynamics.matcher(metadata) {
-                let mut by_cs = try_lock!(self.by_cs.write(), else return self.base_interest());
-                by_cs.insert(metadata.callsite(), matcher);
-                return Interest::always();
-            }
-        }
-
-        // Otherwise, check if any of our static filters enable this metadata.
-        if self.statics.enabled(metadata) {
-            Interest::always()
-        } else {
-            self.base_interest()
-        }
-    }
-
-    fn max_level_hint(&self) -> Option<LevelFilter> {
-        if self.dynamics.has_value_filters() {
-            // If we perform any filtering on span field *values*, we will
-            // enable *all* spans, because their field values are not known
-            // until recording.
-            return Some(LevelFilter::TRACE);
-        }
-        std::cmp::max(
-            self.statics.max_level.into(),
-            self.dynamics.max_level.into(),
-        )
-    }
+    // === filtering methods ===
 
-    fn enabled(&self, metadata: &Metadata<'_>, _: Context<'_, S>) -> bool {
+    /// Returns `true` if this `EnvFilter` would enable the provided `metadata`
+    /// in the current context.
+    ///
+    /// This is equivalent to calling the [`Layer::enabled`] or
+    /// [`Filter::enabled`] methods on `EnvFilter`'s implementations of those
+    /// traits, but it does not require the trait to be in scope.
+    pub fn enabled<S>(&self, metadata: &Metadata<'_>, _: Context<'_, S>) -> bool {
         let level = metadata.level();
 
         // is it possible for a dynamic filter directive to enable this event?
-        // if not, we can avoid the thread local access + iterating over the
+        // if not, we can avoid the thread loca'l access + iterating over the
         // spans in the current scope.
         if self.has_dynamics && self.dynamics.max_level >= *level {
             if metadata.is_span() {
@@ -420,14 +495,15 @@ impl<S: Subscriber> Layer<S> for EnvFilter {
                 }
             }
 
-            let enabled_by_scope = SCOPE.with(|scope| {
-                for filter in scope.borrow().iter() {
+            let enabled_by_scope = {
+                let scope = self.scope.get_or_default().borrow();
+                for filter in &*scope {
                     if filter >= level {
                         return true;
                     }
                 }
                 false
-            });
+            };
             if enabled_by_scope {
                 return true;
             }
@@ -443,7 +519,33 @@ impl<S: Subscriber> Layer<S> for EnvFilter {
         false
     }
 
-    fn on_new_span(&self, attrs: &span::Attributes<'_>, id: &span::Id, _: Context<'_, S>) {
+    /// Returns an optional hint of the highest [verbosity level][level] that
+    /// this `EnvFilter` will enable.
+    ///
+    /// This is equivalent to calling the [`Layer::max_level_hint`] or
+    /// [`Filter::max_level_hint`] methods on `EnvFilter`'s implementations of those
+    /// traits, but it does not require the trait to be in scope.
+    ///
+    /// [level]: tracing_core::metadata::Level
+    pub fn max_level_hint(&self) -> Option<LevelFilter> {
+        if self.dynamics.has_value_filters() {
+            // If we perform any filtering on span field *values*, we will
+            // enable *all* spans, because their field values are not known
+            // until recording.
+            return Some(LevelFilter::TRACE);
+        }
+        std::cmp::max(
+            self.statics.max_level.into(),
+            self.dynamics.max_level.into(),
+        )
+    }
+
+    /// Informs the filter that a new span was created.
+    ///
+    /// This is equivalent to calling the [`Layer::on_new_span`] or
+    /// [`Filter::on_new_span`] methods on `EnvFilter`'s implementations of those
+    /// traits, but it does not require the trait to be in scope.
+    pub fn on_new_span<S>(&self, attrs: &span::Attributes<'_>, id: &span::Id, _: Context<'_, S>) {
         let by_cs = try_lock!(self.by_cs.read());
         if let Some(cs) = by_cs.get(&attrs.metadata().callsite()) {
             let span = cs.to_span_match(attrs);
@@ -451,28 +553,37 @@ impl<S: Subscriber> Layer<S> for EnvFilter {
         }
     }
 
-    fn on_record(&self, id: &span::Id, values: &span::Record<'_>, _: Context<'_, S>) {
-        if let Some(span) = try_lock!(self.by_id.read()).get(id) {
-            span.record_update(values);
-        }
-    }
-
-    fn on_enter(&self, id: &span::Id, _: Context<'_, S>) {
+    /// Informs the filter that the span with the provided `id` was entered.
+    ///
+    /// This is equivalent to calling the [`Layer::on_enter`] or
+    /// [`Filter::on_enter`] methods on `EnvFilter`'s implementations of those
+    /// traits, but it does not require the trait to be in scope.
+    pub fn on_enter<S>(&self, id: &span::Id, _: Context<'_, S>) {
         // XXX: This is where _we_ could push IDs to the stack instead, and use
         // that to allow changing the filter while a span is already entered.
         // But that might be much less efficient...
         if let Some(span) = try_lock!(self.by_id.read()).get(id) {
-            SCOPE.with(|scope| scope.borrow_mut().push(span.level()));
+            self.scope.get_or_default().borrow_mut().push(span.level());
         }
     }
 
-    fn on_exit(&self, id: &span::Id, _: Context<'_, S>) {
+    /// Informs the filter that the span with the provided `id` was exited.
+    ///
+    /// This is equivalent to calling the [`Layer::on_exit`] or
+    /// [`Filter::on_exit`] methods on `EnvFilter`'s implementations of those
+    /// traits, but it does not require the trait to be in scope.
+    pub fn on_exit<S>(&self, id: &span::Id, _: Context<'_, S>) {
         if self.cares_about_span(id) {
-            SCOPE.with(|scope| scope.borrow_mut().pop());
+            self.scope.get_or_default().borrow_mut().pop();
         }
     }
 
-    fn on_close(&self, id: span::Id, _: Context<'_, S>) {
+    /// Informs the filter that the span with the provided `id` was closed.
+    ///
+    /// This is equivalent to calling the [`Layer::on_close`] or
+    /// [`Filter::on_close`] methods on `EnvFilter`'s implementations of those
+    /// traits, but it does not require the trait to be in scope.
+    pub fn on_close<S>(&self, id: span::Id, _: Context<'_, S>) {
         // If we don't need to acquire a write lock, avoid doing so.
         if !self.cares_about_span(&id) {
             return;
@@ -481,6 +592,140 @@ impl<S: Subscriber> Layer<S> for EnvFilter {
         let mut spans = try_lock!(self.by_id.write());
         spans.remove(&id);
     }
+
+    /// Informs the filter that the span with the provided `id` recorded the
+    /// provided field `values`.
+    ///
+    /// This is equivalent to calling the [`Layer::on_record`] or
+    /// [`Filter::on_record`] methods on `EnvFilter`'s implementations of those
+    /// traits, but it does not require the trait to be in scope
+    pub fn on_record<S>(&self, id: &span::Id, values: &span::Record<'_>, _: Context<'_, S>) {
+        if let Some(span) = try_lock!(self.by_id.read()).get(id) {
+            span.record_update(values);
+        }
+    }
+
+    fn cares_about_span(&self, span: &span::Id) -> bool {
+        let spans = try_lock!(self.by_id.read(), else return false);
+        spans.contains_key(span)
+    }
+
+    fn base_interest(&self) -> Interest {
+        if self.has_dynamics {
+            Interest::sometimes()
+        } else {
+            Interest::never()
+        }
+    }
+
+    fn register_callsite(&self, metadata: &'static Metadata<'static>) -> Interest {
+        if self.has_dynamics && metadata.is_span() {
+            // If this metadata describes a span, first, check if there is a
+            // dynamic filter that should be constructed for it. If so, it
+            // should always be enabled, since it influences filtering.
+            if let Some(matcher) = self.dynamics.matcher(metadata) {
+                let mut by_cs = try_lock!(self.by_cs.write(), else return self.base_interest());
+                by_cs.insert(metadata.callsite(), matcher);
+                return Interest::always();
+            }
+        }
+
+        // Otherwise, check if any of our static filters enable this metadata.
+        if self.statics.enabled(metadata) {
+            Interest::always()
+        } else {
+            self.base_interest()
+        }
+    }
+}
+
+impl<S: Subscriber> Layer<S> for EnvFilter {
+    #[inline]
+    fn register_callsite(&self, metadata: &'static Metadata<'static>) -> Interest {
+        EnvFilter::register_callsite(self, metadata)
+    }
+
+    #[inline]
+    fn max_level_hint(&self) -> Option<LevelFilter> {
+        EnvFilter::max_level_hint(self)
+    }
+
+    #[inline]
+    fn enabled(&self, metadata: &Metadata<'_>, ctx: Context<'_, S>) -> bool {
+        self.enabled(metadata, ctx)
+    }
+
+    #[inline]
+    fn on_new_span(&self, attrs: &span::Attributes<'_>, id: &span::Id, ctx: Context<'_, S>) {
+        self.on_new_span(attrs, id, ctx)
+    }
+
+    #[inline]
+    fn on_record(&self, id: &span::Id, values: &span::Record<'_>, ctx: Context<'_, S>) {
+        self.on_record(id, values, ctx);
+    }
+
+    #[inline]
+    fn on_enter(&self, id: &span::Id, ctx: Context<'_, S>) {
+        self.on_enter(id, ctx);
+    }
+
+    #[inline]
+    fn on_exit(&self, id: &span::Id, ctx: Context<'_, S>) {
+        self.on_exit(id, ctx);
+    }
+
+    #[inline]
+    fn on_close(&self, id: span::Id, ctx: Context<'_, S>) {
+        self.on_close(id, ctx);
+    }
+}
+
+feature! {
+    #![all(feature = "registry", feature = "std")]
+    use crate::layer::Filter;
+
+    impl<S> Filter<S> for EnvFilter {
+        #[inline]
+        fn enabled(&self, meta: &Metadata<'_>, ctx: &Context<'_, S>) -> bool {
+            self.enabled(meta, ctx.clone())
+        }
+
+        #[inline]
+        fn callsite_enabled(&self, meta: &'static Metadata<'static>) -> Interest {
+            self.register_callsite(meta)
+        }
+
+        #[inline]
+        fn max_level_hint(&self) -> Option<LevelFilter> {
+            EnvFilter::max_level_hint(self)
+        }
+
+        #[inline]
+        fn on_new_span(&self, attrs: &span::Attributes<'_>, id: &span::Id, ctx: Context<'_, S>) {
+            self.on_new_span(attrs, id, ctx)
+        }
+
+        #[inline]
+        fn on_record(&self, id: &span::Id, values: &span::Record<'_>, ctx: Context<'_, S>) {
+            self.on_record(id, values, ctx);
+        }
+
+        #[inline]
+        fn on_enter(&self, id: &span::Id, ctx: Context<'_, S>) {
+            self.on_enter(id, ctx);
+        }
+
+        #[inline]
+        fn on_exit(&self, id: &span::Id, ctx: Context<'_, S>) {
+            self.on_exit(id, ctx);
+        }
+
+        #[inline]
+        fn on_close(&self, id: span::Id, ctx: Context<'_, S>) {
+            self.on_close(id, ctx);
+        }
+    }
 }
 
 impl FromStr for EnvFilter {
@@ -502,7 +747,7 @@ where
 
 impl Default for EnvFilter {
     fn default() -> Self {
-        Self::from_directives(std::iter::empty())
+        Builder::default().from_directives(std::iter::empty())
     }
 }
 
@@ -735,4 +980,12 @@ mod tests {
             [span2{bar=2 baz=false}],crate2[{quux=\"quuux\"}]=debug",
         );
     }
+
+    #[test]
+    fn parse_empty_string() {
+        // There is no corresponding test for [`Builder::parse_lossy`] as failed
+        // parsing does not produce any observable side effects. If this test fails
+        // check that [`Builder::parse_lossy`] is behaving correctly as well.
+        assert!(EnvFilter::builder().parse("").is_ok());
+    }
 }
diff --git a/vendor/tracing-subscriber-0.3.3/src/filter/filter_fn.rs b/vendor/tracing-subscriber/src/filter/filter_fn.rs
index 332bf860a..332bf860a 100644
--- a/vendor/tracing-subscriber-0.3.3/src/filter/filter_fn.rs
+++ b/vendor/tracing-subscriber/src/filter/filter_fn.rs
diff --git a/vendor/tracing-subscriber-0.3.3/src/filter/layer_filters.rs b/vendor/tracing-subscriber/src/filter/layer_filters/mod.rs
index e77fd3751..e50ee6f00 100644
--- a/vendor/tracing-subscriber-0.3.3/src/filter/layer_filters.rs
+++ b/vendor/tracing-subscriber/src/filter/layer_filters/mod.rs
@@ -37,14 +37,16 @@ use std::{
     cell::{Cell, RefCell},
     fmt,
     marker::PhantomData,
+    ops::Deref,
     sync::Arc,
     thread_local,
 };
 use tracing_core::{
     span,
     subscriber::{Interest, Subscriber},
-    Event, Metadata,
+    Dispatch, Event, Metadata,
 };
+pub mod combinator;
 
 /// A [`Layer`] that wraps an inner [`Layer`] and adds a [`Filter`] which
 /// controls what spans and events are enabled for that layer.
@@ -158,7 +160,288 @@ thread_local! {
     pub(crate) static FILTERING: FilterState = FilterState::new();
 }
 
+/// Extension trait adding [combinators] for combining [`Filter`].
+///
+/// [combinators]: crate::filter::combinator
+/// [`Filter`]: crate::layer::Filter
+pub trait FilterExt<S>: layer::Filter<S> {
+    /// Combines this [`Filter`] with another [`Filter`] s so that spans and
+    /// events are enabled if and only if *both* filters return `true`.
+    ///
+    /// # Examples
+    ///
+    /// Enabling spans or events if they have both a particular target *and* are
+    /// above a certain level:
+    ///
+    /// ```
+    /// use tracing_subscriber::{
+    ///     filter::{filter_fn, LevelFilter, FilterExt},
+    ///     prelude::*,
+    /// };
+    ///
+    /// // Enables spans and events with targets starting with `interesting_target`:
+    /// let target_filter = filter_fn(|meta| {
+    ///     meta.target().starts_with("interesting_target")
+    /// });
+    ///
+    /// // Enables spans and events with levels `INFO` and below:
+    /// let level_filter = LevelFilter::INFO;
+    ///
+    /// // Combine the two filters together, returning a filter that only enables
+    /// // spans and events that *both* filters will enable:
+    /// let filter = target_filter.and(level_filter);
+    ///
+    /// tracing_subscriber::registry()
+    ///     .with(tracing_subscriber::fmt::layer().with_filter(filter))
+    ///     .init();
+    ///
+    /// // This event will *not* be enabled:
+    /// tracing::info!("an event with an uninteresting target");
+    ///
+    /// // This event *will* be enabled:
+    /// tracing::info!(target: "interesting_target", "a very interesting event");
+    ///
+    /// // This event will *not* be enabled:
+    /// tracing::debug!(target: "interesting_target", "interesting debug event...");
+    /// ```
+    ///
+    /// [`Filter`]: crate::layer::Filter
+    fn and<B>(self, other: B) -> combinator::And<Self, B, S>
+    where
+        Self: Sized,
+        B: layer::Filter<S>,
+    {
+        combinator::And::new(self, other)
+    }
+
+    /// Combines two [`Filter`]s so that spans and events are enabled if *either* filter
+    /// returns `true`.
+    ///
+    /// # Examples
+    ///
+    /// Enabling spans and events at the `INFO` level and above, and all spans
+    /// and events with a particular target:
+    /// ```
+    /// use tracing_subscriber::{
+    ///     filter::{filter_fn, LevelFilter, FilterExt},
+    ///     prelude::*,
+    /// };
+    ///
+    /// // Enables spans and events with targets starting with `interesting_target`:
+    /// let target_filter = filter_fn(|meta| {
+    ///     meta.target().starts_with("interesting_target")
+    /// });
+    ///
+    /// // Enables spans and events with levels `INFO` and below:
+    /// let level_filter = LevelFilter::INFO;
+    ///
+    /// // Combine the two filters together so that a span or event is enabled
+    /// // if it is at INFO or lower, or if it has a target starting with
+    /// // `interesting_target`.
+    /// let filter = level_filter.or(target_filter);
+    ///
+    /// tracing_subscriber::registry()
+    ///     .with(tracing_subscriber::fmt::layer().with_filter(filter))
+    ///     .init();
+    ///
+    /// // This event will *not* be enabled:
+    /// tracing::debug!("an uninteresting event");
+    ///
+    /// // This event *will* be enabled:
+    /// tracing::info!("an uninteresting INFO event");
+    ///
+    /// // This event *will* be enabled:
+    /// tracing::info!(target: "interesting_target", "a very interesting event");
+    ///
+    /// // This event *will* be enabled:
+    /// tracing::debug!(target: "interesting_target", "interesting debug event...");
+    /// ```
+    ///
+    /// Enabling a higher level for a particular target by using `or` in
+    /// conjunction with the [`and`] combinator:
+    ///
+    /// ```
+    /// use tracing_subscriber::{
+    ///     filter::{filter_fn, LevelFilter, FilterExt},
+    ///     prelude::*,
+    /// };
+    ///
+    /// // This filter will enable spans and events with targets beginning with
+    /// // `my_crate`:
+    /// let my_crate = filter_fn(|meta| {
+    ///     meta.target().starts_with("my_crate")
+    /// });
+    ///
+    /// let filter = my_crate
+    ///     // Combine the `my_crate` filter with a `LevelFilter` to produce a
+    ///     // filter that will enable the `INFO` level and lower for spans and
+    ///     // events with `my_crate` targets:
+    ///     .and(LevelFilter::INFO)
+    ///     // If a span or event *doesn't* have a target beginning with
+    ///     // `my_crate`, enable it if it has the `WARN` level or lower:
+    ///     .or(LevelFilter::WARN);
+    ///
+    /// tracing_subscriber::registry()
+    ///     .with(tracing_subscriber::fmt::layer().with_filter(filter))
+    ///     .init();
+    /// ```
+    ///
+    /// [`Filter`]: crate::layer::Filter
+    /// [`and`]: FilterExt::and
+    fn or<B>(self, other: B) -> combinator::Or<Self, B, S>
+    where
+        Self: Sized,
+        B: layer::Filter<S>,
+    {
+        combinator::Or::new(self, other)
+    }
+
+    /// Inverts `self`, returning a filter that enables spans and events only if
+    /// `self` would *not* enable them.
+    ///
+    /// This inverts the values returned by the [`enabled`] and [`callsite_enabled`]
+    /// methods on the wrapped filter; it does *not* invert [`event_enabled`], as
+    /// filters which do not implement filtering on event field values will return
+    /// the default `true` even for events that their [`enabled`] method disables.
+    ///
+    /// Consider a normal filter defined as:
+    ///
+    /// ```ignore (pseudo-code)
+    /// // for spans
+    /// match callsite_enabled() {
+    ///     ALWAYS => on_span(),
+    ///     SOMETIMES => if enabled() { on_span() },
+    ///     NEVER => (),
+    /// }
+    /// // for events
+    /// match callsite_enabled() {
+    ///    ALWAYS => on_event(),
+    ///    SOMETIMES => if enabled() && event_enabled() { on_event() },
+    ///    NEVER => (),
+    /// }
+    /// ```
+    ///
+    /// and an inverted filter defined as:
+    ///
+    /// ```ignore (pseudo-code)
+    /// // for spans
+    /// match callsite_enabled() {
+    ///     ALWAYS => (),
+    ///     SOMETIMES => if !enabled() { on_span() },
+    ///     NEVER => on_span(),
+    /// }
+    /// // for events
+    /// match callsite_enabled() {
+    ///     ALWAYS => (),
+    ///     SOMETIMES => if !enabled() { on_event() },
+    ///     NEVER => on_event(),
+    /// }
+    /// ```
+    ///
+    /// A proper inversion would do `!(enabled() && event_enabled())` (or
+    /// `!enabled() || !event_enabled()`), but because of the implicit `&&`
+    /// relation between `enabled` and `event_enabled`, it is difficult to
+    /// short circuit and not call the wrapped `event_enabled`.
+    ///
+    /// A combinator which remembers the result of `enabled` in order to call
+    /// `event_enabled` only when `enabled() == true` is possible, but requires
+    /// additional thread-local mutable state to support a very niche use case.
+    //
+    //  Also, it'd mean the wrapped layer's `enabled()` always gets called and
+    //  globally applied to events where it doesn't today, since we can't know
+    //  what `event_enabled` will say until we have the event to call it with.
+    ///
+    /// [`Filter`]: crate::subscribe::Filter
+    /// [`enabled`]: crate::subscribe::Filter::enabled
+    /// [`event_enabled`]: crate::subscribe::Filter::event_enabled
+    /// [`callsite_enabled`]: crate::subscribe::Filter::callsite_enabled
+    fn not(self) -> combinator::Not<Self, S>
+    where
+        Self: Sized,
+    {
+        combinator::Not::new(self)
+    }
+
+    /// [Boxes] `self`, erasing its concrete type.
+    ///
+    /// This is equivalent to calling [`Box::new`], but in method form, so that
+    /// it can be used when chaining combinator methods.
+    ///
+    /// # Examples
+    ///
+    /// When different combinations of filters are used conditionally, they may
+    /// have different types. For example, the following code won't compile,
+    /// since the `if` and `else` clause produce filters of different types:
+    ///
+    /// ```compile_fail
+    /// use tracing_subscriber::{
+    ///     filter::{filter_fn, LevelFilter, FilterExt},
+    ///     prelude::*,
+    /// };
+    ///
+    /// let enable_bar_target: bool = // ...
+    /// # false;
+    ///
+    /// let filter = if enable_bar_target {
+    ///     filter_fn(|meta| meta.target().starts_with("foo"))
+    ///         // If `enable_bar_target` is true, add a `filter_fn` enabling
+    ///         // spans and events with the target `bar`:
+    ///         .or(filter_fn(|meta| meta.target().starts_with("bar")))
+    ///         .and(LevelFilter::INFO)
+    /// } else {
+    ///     filter_fn(|meta| meta.target().starts_with("foo"))
+    ///         .and(LevelFilter::INFO)
+    /// };
+    ///
+    /// tracing_subscriber::registry()
+    ///     .with(tracing_subscriber::fmt::layer().with_filter(filter))
+    ///     .init();
+    /// ```
+    ///
+    /// By using `boxed`, the types of the two different branches can be erased,
+    /// so the assignment to the `filter` variable is valid (as both branches
+    /// have the type `Box<dyn Filter<S> + Send + Sync + 'static>`). The
+    /// following code *does* compile:
+    ///
+    /// ```
+    /// use tracing_subscriber::{
+    ///     filter::{filter_fn, LevelFilter, FilterExt},
+    ///     prelude::*,
+    /// };
+    ///
+    /// let enable_bar_target: bool = // ...
+    /// # false;
+    ///
+    /// let filter = if enable_bar_target {
+    ///     filter_fn(|meta| meta.target().starts_with("foo"))
+    ///         .or(filter_fn(|meta| meta.target().starts_with("bar")))
+    ///         .and(LevelFilter::INFO)
+    ///         // Boxing the filter erases its type, so both branches now
+    ///         // have the same type.
+    ///         .boxed()
+    /// } else {
+    ///     filter_fn(|meta| meta.target().starts_with("foo"))
+    ///         .and(LevelFilter::INFO)
+    ///         .boxed()
+    /// };
+    ///
+    /// tracing_subscriber::registry()
+    ///     .with(tracing_subscriber::fmt::layer().with_filter(filter))
+    ///     .init();
+    /// ```
+    ///
+    /// [Boxes]: std::boxed
+    /// [`Box::new`]: std::boxed::Box::new
+    fn boxed(self) -> Box<dyn layer::Filter<S> + Send + Sync + 'static>
+    where
+        Self: Sized + Send + Sync + 'static,
+    {
+        Box::new(self)
+    }
+}
+
 // === impl Filter ===
+
 #[cfg(feature = "registry")]
 #[cfg_attr(docsrs, doc(cfg(feature = "registry")))]
 impl<S> layer::Filter<S> for LevelFilter {
@@ -179,38 +462,35 @@ impl<S> layer::Filter<S> for LevelFilter {
     }
 }
 
-impl<S> layer::Filter<S> for Arc<dyn layer::Filter<S> + Send + Sync + 'static> {
-    #[inline]
-    fn enabled(&self, meta: &Metadata<'_>, cx: &Context<'_, S>) -> bool {
-        (**self).enabled(meta, cx)
-    }
+macro_rules! filter_impl_body {
+    () => {
+        #[inline]
+        fn enabled(&self, meta: &Metadata<'_>, cx: &Context<'_, S>) -> bool {
+            self.deref().enabled(meta, cx)
+        }
 
-    #[inline]
-    fn callsite_enabled(&self, meta: &'static Metadata<'static>) -> Interest {
-        (**self).callsite_enabled(meta)
-    }
+        #[inline]
+        fn callsite_enabled(&self, meta: &'static Metadata<'static>) -> Interest {
+            self.deref().callsite_enabled(meta)
+        }
 
-    #[inline]
-    fn max_level_hint(&self) -> Option<LevelFilter> {
-        (**self).max_level_hint()
-    }
+        #[inline]
+        fn max_level_hint(&self) -> Option<LevelFilter> {
+            self.deref().max_level_hint()
+        }
+    };
 }
 
-impl<S> layer::Filter<S> for Box<dyn layer::Filter<S> + Send + Sync + 'static> {
-    #[inline]
-    fn enabled(&self, meta: &Metadata<'_>, cx: &Context<'_, S>) -> bool {
-        (**self).enabled(meta, cx)
-    }
-
-    #[inline]
-    fn callsite_enabled(&self, meta: &'static Metadata<'static>) -> Interest {
-        (**self).callsite_enabled(meta)
-    }
+#[cfg(feature = "registry")]
+#[cfg_attr(docsrs, doc(cfg(feature = "registry")))]
+impl<S> layer::Filter<S> for Arc<dyn layer::Filter<S> + Send + Sync + 'static> {
+    filter_impl_body!();
+}
 
-    #[inline]
-    fn max_level_hint(&self) -> Option<LevelFilter> {
-        (**self).max_level_hint()
-    }
+#[cfg(feature = "registry")]
+#[cfg_attr(docsrs, doc(cfg(feature = "registry")))]
+impl<S> layer::Filter<S> for Box<dyn layer::Filter<S> + Send + Sync + 'static> {
+    filter_impl_body!();
 }
 
 // === impl Filtered ===
@@ -247,6 +527,78 @@ impl<L, F, S> Filtered<L, F, S> {
     fn did_enable(&self, f: impl FnOnce()) {
         FILTERING.with(|filtering| filtering.did_enable(self.id(), f))
     }
+
+    /// Borrows the [`Filter`](crate::layer::Filter) used by this layer.
+    pub fn filter(&self) -> &F {
+        &self.filter
+    }
+
+    /// Mutably borrows the [`Filter`](crate::layer::Filter) used by this layer.
+    ///
+    /// When this layer can be mutably borrowed, this may be used to mutate the filter.
+    /// Generally, this will primarily be used with the
+    /// [`reload::Handle::modify`](crate::reload::Handle::modify) method.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// # use tracing::info;
+    /// # use tracing_subscriber::{filter,fmt,reload,Registry,prelude::*};
+    /// # fn main() {
+    /// let filtered_layer = fmt::Layer::default().with_filter(filter::LevelFilter::WARN);
+    /// let (filtered_layer, reload_handle) = reload::Layer::new(filtered_layer);
+    /// #
+    /// # // specifying the Registry type is required
+    /// # let _: &reload::Handle<filter::Filtered<fmt::Layer<Registry>,
+    /// # filter::LevelFilter, Registry>,Registry>
+    /// # = &reload_handle;
+    /// #
+    /// info!("This will be ignored");
+    /// reload_handle.modify(|layer| *layer.filter_mut() = filter::LevelFilter::INFO);
+    /// info!("This will be logged");
+    /// # }
+    /// ```
+    pub fn filter_mut(&mut self) -> &mut F {
+        &mut self.filter
+    }
+
+    /// Borrows the inner [`Layer`] wrapped by this `Filtered` layer.
+    pub fn inner(&self) -> &L {
+        &self.layer
+    }
+
+    /// Mutably borrows the inner [`Layer`] wrapped by this `Filtered` layer.
+    ///
+    /// This method is primarily expected to be used with the
+    /// [`reload::Handle::modify`](crate::reload::Handle::modify) method.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// # use tracing::info;
+    /// # use tracing_subscriber::{filter,fmt,reload,Registry,prelude::*};
+    /// # fn non_blocking<T: std::io::Write>(writer: T) -> (fn() -> std::io::Stdout) {
+    /// #   std::io::stdout
+    /// # }
+    /// # fn main() {
+    /// let filtered_layer = fmt::layer().with_writer(non_blocking(std::io::stderr())).with_filter(filter::LevelFilter::INFO);
+    /// let (filtered_layer, reload_handle) = reload::Layer::new(filtered_layer);
+    /// #
+    /// # // specifying the Registry type is required
+    /// # let _: &reload::Handle<filter::Filtered<fmt::Layer<Registry, _, _, fn() -> std::io::Stdout>,
+    /// # filter::LevelFilter, Registry>, Registry>
+    /// # = &reload_handle;
+    /// #
+    /// info!("This will be logged to stderr");
+    /// reload_handle.modify(|layer| *layer.inner_mut().writer_mut() = non_blocking(std::io::stdout()));
+    /// info!("This will be logged to stdout");
+    /// # }
+    /// ```
+    ///
+    /// [subscriber]: Subscribe
+    pub fn inner_mut(&mut self) -> &mut L {
+        &mut self.layer
+    }
 }
 
 impl<S, L, F> Layer<S> for Filtered<L, F, S>
@@ -255,6 +607,10 @@ where
     F: layer::Filter<S> + 'static,
     L: Layer<S>,
 {
+    fn on_register_dispatch(&self, collector: &Dispatch) {
+        self.layer.on_register_dispatch(collector);
+    }
+
     fn on_layer(&mut self, subscriber: &mut S) {
         self.id = MagicPlfDowncastMarker(subscriber.register_filter());
         self.layer.on_layer(subscriber);
@@ -322,7 +678,9 @@ where
 
     fn on_new_span(&self, attrs: &span::Attributes<'_>, id: &span::Id, cx: Context<'_, S>) {
         self.did_enable(|| {
-            self.layer.on_new_span(attrs, id, cx.with_filter(self.id()));
+            let cx = cx.with_filter(self.id());
+            self.filter.on_new_span(attrs, id, cx.clone());
+            self.layer.on_new_span(attrs, id, cx);
         })
     }
 
@@ -333,6 +691,7 @@ where
 
     fn on_record(&self, span: &span::Id, values: &span::Record<'_>, cx: Context<'_, S>) {
         if let Some(cx) = cx.if_enabled_for(span, self.id()) {
+            self.filter.on_record(span, values, cx.clone());
             self.layer.on_record(span, values, cx)
         }
     }
@@ -345,6 +704,22 @@ where
         }
     }
 
+    fn event_enabled(&self, event: &Event<'_>, cx: Context<'_, S>) -> bool {
+        let cx = cx.with_filter(self.id());
+        let enabled = FILTERING
+            .with(|filtering| filtering.and(self.id(), || self.filter.event_enabled(event, &cx)));
+
+        if enabled {
+            // If the filter enabled this event, ask the wrapped subscriber if
+            // _it_ wants it --- it might have a global filter.
+            self.layer.event_enabled(event, cx)
+        } else {
+            // Otherwise, return `true`. See the comment in `enabled` for why this
+            // is necessary.
+            true
+        }
+    }
+
     fn on_event(&self, event: &Event<'_>, cx: Context<'_, S>) {
         self.did_enable(|| {
             self.layer.on_event(event, cx.with_filter(self.id()));
@@ -353,19 +728,22 @@ where
 
     fn on_enter(&self, id: &span::Id, cx: Context<'_, S>) {
         if let Some(cx) = cx.if_enabled_for(id, self.id()) {
-            self.layer.on_enter(id, cx)
+            self.filter.on_enter(id, cx.clone());
+            self.layer.on_enter(id, cx);
         }
     }
 
     fn on_exit(&self, id: &span::Id, cx: Context<'_, S>) {
         if let Some(cx) = cx.if_enabled_for(id, self.id()) {
-            self.layer.on_exit(id, cx)
+            self.filter.on_exit(id, cx.clone());
+            self.layer.on_exit(id, cx);
         }
     }
 
     fn on_close(&self, id: span::Id, cx: Context<'_, S>) {
         if let Some(cx) = cx.if_enabled_for(&id, self.id()) {
-            self.layer.on_close(id, cx)
+            self.filter.on_close(id.clone(), cx.clone());
+            self.layer.on_close(id, cx);
         }
     }
 
@@ -544,6 +922,10 @@ impl fmt::Binary for FilterId {
     }
 }
 
+// === impl FilterExt ===
+
+impl<F, S> FilterExt<S> for F where F: layer::Filter<S> {}
+
 // === impl FilterMap ===
 
 impl FilterMap {
@@ -709,6 +1091,14 @@ impl FilterState {
         }
     }
 
+    /// Run a second filtering pass, e.g. for Subscribe::event_enabled.
+    fn and(&self, filter: FilterId, f: impl FnOnce() -> bool) -> bool {
+        let map = self.enabled.get();
+        let enabled = map.is_enabled(filter) && f();
+        self.enabled.set(map.set(filter, enabled));
+        enabled
+    }
+
     /// Clears the current in-progress filter state.
     ///
     /// This resets the [`FilterMap`] and current [`Interest`] as well as
diff --git a/vendor/tracing-subscriber-0.3.3/src/filter/level.rs b/vendor/tracing-subscriber/src/filter/level.rs
index 0fa601260..0fa601260 100644
--- a/vendor/tracing-subscriber-0.3.3/src/filter/level.rs
+++ b/vendor/tracing-subscriber/src/filter/level.rs
diff --git a/vendor/tracing-subscriber-0.3.3/src/filter/mod.rs b/vendor/tracing-subscriber/src/filter/mod.rs
index 000a27195..000a27195 100644
--- a/vendor/tracing-subscriber-0.3.3/src/filter/mod.rs
+++ b/vendor/tracing-subscriber/src/filter/mod.rs
diff --git a/vendor/tracing-subscriber-0.3.3/src/filter/targets.rs b/vendor/tracing-subscriber/src/filter/targets.rs
index e0c7fcf82..e1407114b 100644
--- a/vendor/tracing-subscriber-0.3.3/src/filter/targets.rs
+++ b/vendor/tracing-subscriber/src/filter/targets.rs
@@ -20,7 +20,7 @@ use core::{
     slice,
     str::FromStr,
 };
-use tracing_core::{Interest, Metadata, Subscriber};
+use tracing_core::{Interest, Level, Metadata, Subscriber};
 
 /// A filter that enables or disables spans and events based on their [target]
 /// and [level].
@@ -111,7 +111,7 @@ use tracing_core::{Interest, Metadata, Subscriber};
 /// by the user at runtime.
 ///
 /// The `Targets` filter can be used as a [per-layer filter][plf] *and* as a
-/// [global filter]:
+/// [global filter][global]:
 ///
 /// ```rust
 /// use tracing_subscriber::{
@@ -277,6 +277,62 @@ impl Targets {
         self
     }
 
+    /// Returns the default level for this filter, if one is set.
+    ///
+    /// The default level is used to filter any spans or events with targets
+    /// that do not match any of the configured set of prefixes.
+    ///
+    /// The default level can be set for a filter either by using
+    /// [`with_default`](Self::with_default) or when parsing from a filter string that includes a
+    /// level without a target (e.g. `"trace"`).
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use tracing_subscriber::filter::{LevelFilter, Targets};
+    ///
+    /// let filter = Targets::new().with_default(LevelFilter::INFO);
+    /// assert_eq!(filter.default_level(), Some(LevelFilter::INFO));
+    ///
+    /// let filter: Targets = "info".parse().unwrap();
+    /// assert_eq!(filter.default_level(), Some(LevelFilter::INFO));
+    /// ```
+    ///
+    /// The default level is `None` if no default is set:
+    ///
+    /// ```
+    /// use tracing_subscriber::filter::Targets;
+    ///
+    /// let filter = Targets::new();
+    /// assert_eq!(filter.default_level(), None);
+    ///
+    /// let filter: Targets = "my_crate=info".parse().unwrap();
+    /// assert_eq!(filter.default_level(), None);
+    /// ```
+    ///
+    /// Note that an unset default level (`None`) behaves like [`LevelFilter::OFF`] when the filter is
+    /// used, but it could also be set explicitly which may be useful to distinguish (such as when
+    /// merging multiple `Targets`).
+    ///
+    /// ```
+    /// use tracing_subscriber::filter::{LevelFilter, Targets};
+    ///
+    /// let filter = Targets::new().with_default(LevelFilter::OFF);
+    /// assert_eq!(filter.default_level(), Some(LevelFilter::OFF));
+    ///
+    /// let filter: Targets = "off".parse().unwrap();
+    /// assert_eq!(filter.default_level(), Some(LevelFilter::OFF));
+    /// ```
+    pub fn default_level(&self) -> Option<LevelFilter> {
+        self.0.directives().into_iter().find_map(|d| {
+            if d.target.is_none() {
+                Some(d.level)
+            } else {
+                None
+            }
+        })
+    }
+
     /// Returns an iterator over the [target]-[`LevelFilter`] pairs in this filter.
     ///
     /// The order of iteration is undefined.
@@ -313,6 +369,35 @@ impl Targets {
             Interest::never()
         }
     }
+
+    /// Returns whether a [target]-[`Level`] pair would be enabled
+    /// by this `Targets`.
+    ///
+    /// This method can be used with [`module_path!`] from `std` as the target
+    /// in order to emulate the behavior of the [`tracing::event!`] and [`tracing::span!`]
+    /// macros.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use tracing_subscriber::filter::{Targets, LevelFilter};
+    /// use tracing_core::Level;
+    ///
+    /// let filter = Targets::new()
+    ///     .with_target("my_crate", Level::INFO)
+    ///     .with_target("my_crate::interesting_module", Level::DEBUG);
+    ///
+    /// assert!(filter.would_enable("my_crate", &Level::INFO));
+    /// assert!(!filter.would_enable("my_crate::interesting_module", &Level::TRACE));
+    /// ```
+    ///
+    /// [target]: tracing_core::Metadata::target
+    /// [`module_path!`]: std::module_path!
+    pub fn would_enable(&self, target: &str, level: &Level) -> bool {
+        // "Correct" to call because `Targets` only produces `StaticDirective`'s with NO
+        // fields
+        self.0.target_enabled(target, level)
+    }
 }
 
 impl<T, L> Extend<(T, L)> for Targets
@@ -657,6 +742,21 @@ mod tests {
     }
 
     #[test]
+    fn targets_default_level() {
+        let filter = expect_parse("crate1::mod1=error,crate1::mod2,crate2=debug,crate3=off");
+        assert_eq!(filter.default_level(), None);
+
+        let filter = expect_parse("crate1::mod1=error,crate1::mod2,crate2=debug,crate3=off")
+            .with_default(LevelFilter::OFF);
+        assert_eq!(filter.default_level(), Some(LevelFilter::OFF));
+
+        let filter = expect_parse("crate1::mod1=error,crate1::mod2,crate2=debug,crate3=off")
+            .with_default(LevelFilter::OFF)
+            .with_default(LevelFilter::INFO);
+        assert_eq!(filter.default_level(), Some(LevelFilter::INFO));
+    }
+
+    #[test]
     // `println!` is only available with `libstd`.
     #[cfg(feature = "std")]
     fn size_of_filters() {
diff --git a/vendor/tracing-subscriber-0.3.3/src/fmt/fmt_layer.rs b/vendor/tracing-subscriber/src/fmt/fmt_layer.rs
index 0e0d5e0eb..6e4e2ac0b 100644
--- a/vendor/tracing-subscriber-0.3.3/src/fmt/fmt_layer.rs
+++ b/vendor/tracing-subscriber/src/fmt/fmt_layer.rs
@@ -56,7 +56,7 @@ use tracing_core::{
 /// # tracing::subscriber::set_global_default(subscriber).unwrap();
 /// ```
 ///
-/// [`Layer`]: ../layer/trait.Layer.html
+/// [`Layer`]: super::layer::Layer
 #[cfg_attr(docsrs, doc(cfg(all(feature = "fmt", feature = "std"))))]
 #[derive(Debug)]
 pub struct Layer<
@@ -70,11 +70,12 @@ pub struct Layer<
     fmt_event: E,
     fmt_span: format::FmtSpanConfig,
     is_ansi: bool,
-    _inner: PhantomData<S>,
+    log_internal_errors: bool,
+    _inner: PhantomData<fn(S)>,
 }
 
 impl<S> Layer<S> {
-    /// Returns a new [`Layer`](struct.Layer.html) with the default configuration.
+    /// Returns a new [`Layer`][self::Layer] with the default configuration.
     pub fn new() -> Self {
         Self::default()
     }
@@ -87,8 +88,8 @@ where
     N: for<'writer> FormatFields<'writer> + 'static,
     W: for<'writer> MakeWriter<'writer> + 'static,
 {
-    /// Sets the [event formatter][`FormatEvent`] that the layer will use to
-    /// format events.
+    /// Sets the [event formatter][`FormatEvent`] that the layer being built will
+    /// use to format events.
     ///
     /// The event formatter may be any type implementing the [`FormatEvent`]
     /// trait, which is implemented for all functions taking a [`FmtContext`], a
@@ -108,7 +109,7 @@ where
     /// ```
     /// [`FormatEvent`]: format::FormatEvent
     /// [`Event`]: tracing::Event
-    /// [`Writer`]: crate::format::Writer
+    /// [`Writer`]: format::Writer
     pub fn event_format<E2>(self, e: E2) -> Layer<S, N, E2, W>
     where
         E2: FormatEvent<S, N> + 'static,
@@ -119,6 +120,37 @@ where
             fmt_span: self.fmt_span,
             make_writer: self.make_writer,
             is_ansi: self.is_ansi,
+            log_internal_errors: self.log_internal_errors,
+            _inner: self._inner,
+        }
+    }
+
+    /// Updates the event formatter by applying a function to the existing event formatter.
+    ///
+    /// This sets the event formatter that the layer being built will use to record fields.
+    ///
+    /// # Examples
+    ///
+    /// Updating an event formatter:
+    ///
+    /// ```rust
+    /// let layer = tracing_subscriber::fmt::layer()
+    ///     .map_event_format(|e| e.compact());
+    /// # // this is necessary for type inference.
+    /// # use tracing_subscriber::Layer as _;
+    /// # let _ = layer.with_subscriber(tracing_subscriber::registry::Registry::default());
+    /// ```
+    pub fn map_event_format<E2>(self, f: impl FnOnce(E) -> E2) -> Layer<S, N, E2, W>
+    where
+        E2: FormatEvent<S, N> + 'static,
+    {
+        Layer {
+            fmt_fields: self.fmt_fields,
+            fmt_event: f(self.fmt_event),
+            fmt_span: self.fmt_span,
+            make_writer: self.make_writer,
+            is_ansi: self.is_ansi,
+            log_internal_errors: self.log_internal_errors,
             _inner: self._inner,
         }
     }
@@ -126,7 +158,7 @@ where
 
 // This needs to be a seperate impl block because they place different bounds on the type parameters.
 impl<S, N, E, W> Layer<S, N, E, W> {
-    /// Sets the [`MakeWriter`] that the [`Layer`] being built will use to write events.
+    /// Sets the [`MakeWriter`] that the layer being built will use to write events.
     ///
     /// # Examples
     ///
@@ -142,9 +174,6 @@ impl<S, N, E, W> Layer<S, N, E, W> {
     /// # use tracing_subscriber::Layer as _;
     /// # let _ = layer.with_subscriber(tracing_subscriber::registry::Registry::default());
     /// ```
-    ///
-    /// [`MakeWriter`]: ../fmt/trait.MakeWriter.html
-    /// [`Layer`]: ../layer/trait.Layer.html
     pub fn with_writer<W2>(self, make_writer: W2) -> Layer<S, N, E, W2>
     where
         W2: for<'writer> MakeWriter<'writer> + 'static,
@@ -154,12 +183,63 @@ impl<S, N, E, W> Layer<S, N, E, W> {
             fmt_event: self.fmt_event,
             fmt_span: self.fmt_span,
             is_ansi: self.is_ansi,
+            log_internal_errors: self.log_internal_errors,
             make_writer,
             _inner: self._inner,
         }
     }
 
-    /// Configures the subscriber to support [`libtest`'s output capturing][capturing] when used in
+    /// Borrows the [writer] for this [`Layer`].
+    ///
+    /// [writer]: MakeWriter
+    pub fn writer(&self) -> &W {
+        &self.make_writer
+    }
+
+    /// Mutably borrows the [writer] for this [`Layer`].
+    ///
+    /// This method is primarily expected to be used with the
+    /// [`reload::Handle::modify`](crate::reload::Handle::modify) method.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// # use tracing::info;
+    /// # use tracing_subscriber::{fmt,reload,Registry,prelude::*};
+    /// # fn non_blocking<T: std::io::Write>(writer: T) -> (fn() -> std::io::Stdout) {
+    /// #   std::io::stdout
+    /// # }
+    /// # fn main() {
+    /// let layer = fmt::layer().with_writer(non_blocking(std::io::stderr()));
+    /// let (layer, reload_handle) = reload::Layer::new(layer);
+    /// #
+    /// # // specifying the Registry type is required
+    /// # let _: &reload::Handle<fmt::Layer<Registry, _, _, _>, Registry> = &reload_handle;
+    /// #
+    /// info!("This will be logged to stderr");
+    /// reload_handle.modify(|layer| *layer.writer_mut() = non_blocking(std::io::stdout()));
+    /// info!("This will be logged to stdout");
+    /// # }
+    /// ```
+    ///
+    /// [writer]: MakeWriter
+    pub fn writer_mut(&mut self) -> &mut W {
+        &mut self.make_writer
+    }
+
+    /// Sets whether this layer should use ANSI terminal formatting
+    /// escape codes (such as colors).
+    ///
+    /// This method is primarily expected to be used with the
+    /// [`reload::Handle::modify`](crate::reload::Handle::modify) method when changing
+    /// the writer.
+    #[cfg(feature = "ansi")]
+    #[cfg_attr(docsrs, doc(cfg(feature = "ansi")))]
+    pub fn set_ansi(&mut self, ansi: bool) {
+        self.is_ansi = ansi;
+    }
+
+    /// Configures the layer to support [`libtest`'s output capturing][capturing] when used in
     /// unit tests.
     ///
     /// See [`TestWriter`] for additional details.
@@ -180,13 +260,14 @@ impl<S, N, E, W> Layer<S, N, E, W> {
     /// ```
     /// [capturing]:
     /// https://doc.rust-lang.org/book/ch11-02-running-tests.html#showing-function-output
-    /// [`TestWriter`]: writer/struct.TestWriter.html
+    /// [`TestWriter`]: super::writer::TestWriter
     pub fn with_test_writer(self) -> Layer<S, N, E, TestWriter> {
         Layer {
             fmt_fields: self.fmt_fields,
             fmt_event: self.fmt_event,
             fmt_span: self.fmt_span,
             is_ansi: self.is_ansi,
+            log_internal_errors: self.log_internal_errors,
             make_writer: TestWriter::default(),
             _inner: self._inner,
         }
@@ -201,6 +282,58 @@ impl<S, N, E, W> Layer<S, N, E, W> {
             ..self
         }
     }
+
+    /// Sets whether to write errors from [`FormatEvent`] to the writer.
+    /// Defaults to true.
+    ///
+    /// By default, `fmt::Layer` will write any `FormatEvent`-internal errors to
+    /// the writer. These errors are unlikely and will only occur if there is a
+    /// bug in the `FormatEvent` implementation or its dependencies.
+    /// 
+    /// If writing to the writer fails, the error message is printed to stderr
+    /// as a fallback.
+    /// 
+    /// [`FormatEvent`]: crate::fmt::FormatEvent
+    pub fn log_internal_errors(self, log_internal_errors: bool) -> Self {
+        Self {
+            log_internal_errors,
+            ..self
+        }
+    }
+
+    /// Updates the [`MakeWriter`] by applying a function to the existing [`MakeWriter`].
+    ///
+    /// This sets the [`MakeWriter`] that the layer being built will use to write events.
+    ///
+    /// # Examples
+    ///
+    /// Redirect output to stderr if level is <= WARN:
+    ///
+    /// ```rust
+    /// use tracing::Level;
+    /// use tracing_subscriber::fmt::{self, writer::MakeWriterExt};
+    ///
+    /// let stderr = std::io::stderr.with_max_level(Level::WARN);
+    /// let layer = fmt::layer()
+    ///     .map_writer(move |w| stderr.or_else(w));
+    /// # // this is necessary for type inference.
+    /// # use tracing_subscriber::Layer as _;
+    /// # let _ = layer.with_subscriber(tracing_subscriber::registry::Registry::default());
+    /// ```
+    pub fn map_writer<W2>(self, f: impl FnOnce(W) -> W2) -> Layer<S, N, E, W2>
+    where
+        W2: for<'writer> MakeWriter<'writer> + 'static,
+    {
+        Layer {
+            fmt_fields: self.fmt_fields,
+            fmt_event: self.fmt_event,
+            fmt_span: self.fmt_span,
+            is_ansi: self.is_ansi,
+            log_internal_errors: self.log_internal_errors,
+            make_writer: f(self.make_writer),
+            _inner: self._inner,
+        }
+    }
 }
 
 impl<S, N, L, T, W> Layer<S, N, format::Format<L, T>, W>
@@ -228,6 +361,7 @@ where
             fmt_span: self.fmt_span,
             make_writer: self.make_writer,
             is_ansi: self.is_ansi,
+            log_internal_errors: self.log_internal_errors,
             _inner: self._inner,
         }
     }
@@ -240,6 +374,7 @@ where
             fmt_span: self.fmt_span.without_time(),
             make_writer: self.make_writer,
             is_ansi: self.is_ansi,
+            log_internal_errors: self.log_internal_errors,
             _inner: self._inner,
         }
     }
@@ -284,7 +419,7 @@ where
     /// `Layer`s added to this subscriber.
     ///
     /// [lifecycle]: https://docs.rs/tracing/latest/tracing/span/index.html#the-span-lifecycle
-    /// [time]: #method.without_time
+    /// [time]: Layer::without_time()
     pub fn with_span_events(self, kind: FmtSpan) -> Self {
         Layer {
             fmt_span: self.fmt_span.with_kind(kind),
@@ -299,6 +434,30 @@ where
             ..self
         }
     }
+    /// Sets whether or not an event's [source code file path][file] is
+    /// displayed.
+    ///
+    /// [file]: tracing_core::Metadata::file
+    pub fn with_file(self, display_filename: bool) -> Layer<S, N, format::Format<L, T>, W> {
+        Layer {
+            fmt_event: self.fmt_event.with_file(display_filename),
+            ..self
+        }
+    }
+
+    /// Sets whether or not an event's [source code line number][line] is
+    /// displayed.
+    ///
+    /// [line]: tracing_core::Metadata::line
+    pub fn with_line_number(
+        self,
+        display_line_number: bool,
+    ) -> Layer<S, N, format::Format<L, T>, W> {
+        Layer {
+            fmt_event: self.fmt_event.with_line_number(display_line_number),
+            ..self
+        }
+    }
 
     /// Sets whether or not an event's level is displayed.
     pub fn with_level(self, display_level: bool) -> Layer<S, N, format::Format<L, T>, W> {
@@ -309,9 +468,9 @@ where
     }
 
     /// Sets whether or not the [thread ID] of the current thread is displayed
-    /// when formatting events
+    /// when formatting events.
     ///
-    /// [thread ID]: https://doc.rust-lang.org/stable/std/thread/struct.ThreadId.html
+    /// [thread ID]: std::thread::ThreadId
     pub fn with_thread_ids(self, display_thread_ids: bool) -> Layer<S, N, format::Format<L, T>, W> {
         Layer {
             fmt_event: self.fmt_event.with_thread_ids(display_thread_ids),
@@ -320,9 +479,9 @@ where
     }
 
     /// Sets whether or not the [name] of the current thread is displayed
-    /// when formatting events
+    /// when formatting events.
     ///
-    /// [name]: https://doc.rust-lang.org/stable/std/thread/index.html#naming-threads
+    /// [name]: std::thread#naming-threads
     pub fn with_thread_names(
         self,
         display_thread_names: bool,
@@ -333,7 +492,7 @@ where
         }
     }
 
-    /// Sets the layer being built to use a [less verbose formatter](../fmt/format/struct.Compact.html).
+    /// Sets the layer being built to use a [less verbose formatter][super::format::Compact].
     pub fn compact(self) -> Layer<S, N, format::Format<format::Compact, T>, W>
     where
         N: for<'writer> FormatFields<'writer> + 'static,
@@ -344,6 +503,7 @@ where
             fmt_span: self.fmt_span,
             make_writer: self.make_writer,
             is_ansi: self.is_ansi,
+            log_internal_errors: self.log_internal_errors,
             _inner: self._inner,
         }
     }
@@ -358,11 +518,12 @@ where
             fmt_span: self.fmt_span,
             make_writer: self.make_writer,
             is_ansi: self.is_ansi,
+            log_internal_errors: self.log_internal_errors,
             _inner: self._inner,
         }
     }
 
-    /// Sets the layer being built to use a [JSON formatter](../fmt/format/struct.Json.html).
+    /// Sets the layer being built to use a [JSON formatter][super::format::Json].
     ///
     /// The full format includes fields from all entered spans.
     ///
@@ -377,7 +538,7 @@ where
     /// - [`Layer::flatten_event`] can be used to enable flattening event fields into the root
     /// object.
     ///
-    /// [`Layer::flatten_event`]: #method.flatten_event
+    /// [`Layer::flatten_event`]: Layer::flatten_event()
     #[cfg(feature = "json")]
     #[cfg_attr(docsrs, doc(cfg(feature = "json")))]
     pub fn json(self) -> Layer<S, format::JsonFields, format::Format<format::Json, T>, W> {
@@ -388,6 +549,7 @@ where
             make_writer: self.make_writer,
             // always disable ANSI escapes in JSON mode!
             is_ansi: false,
+            log_internal_errors: self.log_internal_errors,
             _inner: self._inner,
         }
     }
@@ -398,7 +560,7 @@ where
 impl<S, T, W> Layer<S, format::JsonFields, format::Format<format::Json, T>, W> {
     /// Sets the JSON layer being built to flatten event metadata.
     ///
-    /// See [`format::Json`](../fmt/format/struct.Json.html)
+    /// See [`format::Json`][super::format::Json]
     pub fn flatten_event(
         self,
         flatten_event: bool,
@@ -413,7 +575,7 @@ impl<S, T, W> Layer<S, format::JsonFields, format::Format<format::Json, T>, W> {
     /// Sets whether or not the formatter will include the current span in
     /// formatted events.
     ///
-    /// See [`format::Json`](../fmt/format/struct.Json.html)
+    /// See [`format::Json`][super::format::Json]
     pub fn with_current_span(
         self,
         display_current_span: bool,
@@ -428,7 +590,7 @@ impl<S, T, W> Layer<S, format::JsonFields, format::Format<format::Json, T>, W> {
     /// Sets whether or not the formatter will include a list (from root to leaf)
     /// of all currently entered spans in formatted events.
     ///
-    /// See [`format::Json`](../fmt/format/struct.Json.html)
+    /// See [`format::Json`][super::format::Json]
     pub fn with_span_list(
         self,
         display_span_list: bool,
@@ -454,6 +616,38 @@ impl<S, N, E, W> Layer<S, N, E, W> {
             fmt_span: self.fmt_span,
             make_writer: self.make_writer,
             is_ansi: self.is_ansi,
+            log_internal_errors: self.log_internal_errors,
+            _inner: self._inner,
+        }
+    }
+
+    /// Updates the field formatter by applying a function to the existing field formatter.
+    ///
+    /// This sets the field formatter that the layer being built will use to record fields.
+    ///
+    /// # Examples
+    ///
+    /// Updating a field formatter:
+    ///
+    /// ```rust
+    /// use tracing_subscriber::field::MakeExt;
+    /// let layer = tracing_subscriber::fmt::layer()
+    ///     .map_fmt_fields(|f| f.debug_alt());
+    /// # // this is necessary for type inference.
+    /// # use tracing_subscriber::Layer as _;
+    /// # let _ = layer.with_subscriber(tracing_subscriber::registry::Registry::default());
+    /// ```
+    pub fn map_fmt_fields<N2>(self, f: impl FnOnce(N) -> N2) -> Layer<S, N2, E, W>
+    where
+        N2: for<'writer> FormatFields<'writer> + 'static,
+    {
+        Layer {
+            fmt_event: self.fmt_event,
+            fmt_fields: f(self.fmt_fields),
+            fmt_span: self.fmt_span,
+            make_writer: self.make_writer,
+            is_ansi: self.is_ansi,
+            log_internal_errors: self.log_internal_errors,
             _inner: self._inner,
         }
     }
@@ -467,6 +661,7 @@ impl<S> Default for Layer<S> {
             fmt_span: format::FmtSpanConfig::default(),
             make_writer: io::stdout,
             is_ansi: cfg!(feature = "ansi"),
+            log_internal_errors: false,
             _inner: PhantomData,
         }
     }
@@ -497,7 +692,7 @@ where
 /// formatters are in use, each can store its own formatted representation
 /// without conflicting.
 ///
-/// [extensions]: ../registry/struct.Extensions.html
+/// [extensions]: crate::registry::Extensions
 #[derive(Default)]
 pub struct FormattedFields<E: ?Sized> {
     _format_fields: PhantomData<fn(E)>,
@@ -586,6 +781,11 @@ where
             {
                 fields.was_ansi = self.is_ansi;
                 extensions.insert(fields);
+            } else {
+                eprintln!(
+                    "[tracing-subscriber] Unable to format the following event, ignoring: {:?}",
+                    attrs
+                );
             }
         }
 
@@ -732,7 +932,20 @@ where
                 .is_ok()
             {
                 let mut writer = self.make_writer.make_writer_for(event.metadata());
-                let _ = io::Write::write_all(&mut writer, buf.as_bytes());
+                let res = io::Write::write_all(&mut writer, buf.as_bytes());
+                if self.log_internal_errors {
+                    if let Err(e) = res {
+                        eprintln!("[tracing-subscriber] Unable to write an event to the Writer for this Subscriber! Error: {}\n", e);
+                    }
+                }
+            } else if self.log_internal_errors {
+                let err_msg = format!("Unable to format the following event. Name: {}; Fields: {:?}\n",
+                    event.metadata().name(), event.fields());
+                let mut writer = self.make_writer.make_writer_for(event.metadata());
+                let res = io::Write::write_all(&mut writer, err_msg.as_bytes());
+                if let Err(e) = res {
+                    eprintln!("[tracing-subscriber] Unable to write an \"event formatting error\" to the Writer for this Subscriber! Error: {}\n", e);
+                }
             }
 
             buf.clear();
@@ -821,7 +1034,7 @@ where
     /// If this returns `None`, then no span exists for that ID (either it has
     /// closed or the ID is invalid).
     ///
-    /// [stored data]: ../registry/struct.SpanRef.html
+    /// [stored data]: crate::registry::SpanRef
     #[inline]
     pub fn span(&self, id: &Id) -> Option<SpanRef<'_, S>>
     where
@@ -844,7 +1057,7 @@ where
     ///
     /// If this returns `None`, then we are not currently within a span.
     ///
-    /// [stored data]: ../registry/struct.SpanRef.html
+    /// [stored data]: crate::registry::SpanRef
     #[inline]
     pub fn lookup_current(&self) -> Option<SpanRef<'_, S>>
     where
@@ -1030,6 +1243,60 @@ mod test {
     }
 
     #[test]
+    fn format_error_print_to_stderr() {
+        struct AlwaysError;
+
+        impl std::fmt::Debug for AlwaysError {
+            fn fmt(&self, _f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
+                Err(std::fmt::Error)
+            }
+        }
+
+        let make_writer = MockMakeWriter::default();
+        let subscriber = crate::fmt::Subscriber::builder()
+            .with_writer(make_writer.clone())
+            .with_level(false)
+            .with_ansi(false)
+            .with_timer(MockTime)
+            .finish();
+
+        with_default(subscriber, || {
+            tracing::info!(?AlwaysError);
+        });
+        let actual = sanitize_timings(make_writer.get_string());
+
+        // Only assert the start because the line number and callsite may change.
+        let expected = concat!("Unable to format the following event. Name: event ", file!(), ":");
+        assert!(actual.as_str().starts_with(expected), "\nactual = {}\nshould start with expected = {}\n", actual, expected);
+    }
+
+    #[test]
+    fn format_error_ignore_if_log_internal_errors_is_false() {
+        struct AlwaysError;
+
+        impl std::fmt::Debug for AlwaysError {
+            fn fmt(&self, _f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
+                Err(std::fmt::Error)
+            }
+        }
+
+        let make_writer = MockMakeWriter::default();
+        let subscriber = crate::fmt::Subscriber::builder()
+            .with_writer(make_writer.clone())
+            .with_level(false)
+            .with_ansi(false)
+            .with_timer(MockTime)
+            .log_internal_errors(false)
+            .finish();
+
+        with_default(subscriber, || {
+            tracing::info!(?AlwaysError);
+        });
+        let actual = sanitize_timings(make_writer.get_string());
+        assert_eq!("", actual.as_str());
+    }
+
+    #[test]
     fn synthesize_span_none() {
         let make_writer = MockMakeWriter::default();
         let subscriber = crate::fmt::Subscriber::builder()
diff --git a/vendor/tracing-subscriber-0.3.3/src/fmt/format/json.rs b/vendor/tracing-subscriber/src/fmt/format/json.rs
index cc86f03c7..c2f4d3755 100644
--- a/vendor/tracing-subscriber-0.3.3/src/fmt/format/json.rs
+++ b/vendor/tracing-subscriber/src/fmt/format/json.rs
@@ -23,25 +23,42 @@ use tracing_serde::AsSerde;
 #[cfg(feature = "tracing-log")]
 use tracing_log::NormalizeEvent;
 
-/// Marker for `Format` that indicates that the verbose JSON log format should be used.
+/// Marker for [`Format`] that indicates that the newline-delimited JSON log
+/// format should be used.
 ///
-/// The full format includes fields from all entered spans.
+/// This formatter is intended for production use with systems where structured
+/// logs are consumed as JSON by analysis and viewing tools. The JSON output is
+/// not optimized for human readability; instead, it should be pretty-printed
+/// using external JSON tools such as `jq`, or using a JSON log viewer.
 ///
 /// # Example Output
 ///
-/// ```json
-/// {
-///     "timestamp":"Feb 20 11:28:15.096",
-///     "level":"INFO",
-///     "fields":{"message":"some message","key":"value"}
-///     "target":"mycrate",
-///     "span":{name":"leaf"},
-///     "spans":[{"name":"root"},{"name":"leaf"}],
-/// }
-/// ```
+/// <pre><font color="#4E9A06"><b>:;</b></font> <font color="#4E9A06">cargo</font> run --example fmt-json
+/// <font color="#4E9A06"><b>    Finished</b></font> dev [unoptimized + debuginfo] target(s) in 0.08s
+/// <font color="#4E9A06"><b>     Running</b></font> `target/debug/examples/fmt-json`
+/// {&quot;timestamp&quot;:&quot;2022-02-15T18:47:10.821315Z&quot;,&quot;level&quot;:&quot;INFO&quot;,&quot;fields&quot;:{&quot;message&quot;:&quot;preparing to shave yaks&quot;,&quot;number_of_yaks&quot;:3},&quot;target&quot;:&quot;fmt_json&quot;}
+/// {&quot;timestamp&quot;:&quot;2022-02-15T18:47:10.821422Z&quot;,&quot;level&quot;:&quot;INFO&quot;,&quot;fields&quot;:{&quot;message&quot;:&quot;shaving yaks&quot;},&quot;target&quot;:&quot;fmt_json::yak_shave&quot;,&quot;spans&quot;:[{&quot;yaks&quot;:3,&quot;name&quot;:&quot;shaving_yaks&quot;}]}
+/// {&quot;timestamp&quot;:&quot;2022-02-15T18:47:10.821495Z&quot;,&quot;level&quot;:&quot;TRACE&quot;,&quot;fields&quot;:{&quot;message&quot;:&quot;hello! I&apos;m gonna shave a yak&quot;,&quot;excitement&quot;:&quot;yay!&quot;},&quot;target&quot;:&quot;fmt_json::yak_shave&quot;,&quot;spans&quot;:[{&quot;yaks&quot;:3,&quot;name&quot;:&quot;shaving_yaks&quot;},{&quot;yak&quot;:1,&quot;name&quot;:&quot;shave&quot;}]}
+/// {&quot;timestamp&quot;:&quot;2022-02-15T18:47:10.821546Z&quot;,&quot;level&quot;:&quot;TRACE&quot;,&quot;fields&quot;:{&quot;message&quot;:&quot;yak shaved successfully&quot;},&quot;target&quot;:&quot;fmt_json::yak_shave&quot;,&quot;spans&quot;:[{&quot;yaks&quot;:3,&quot;name&quot;:&quot;shaving_yaks&quot;},{&quot;yak&quot;:1,&quot;name&quot;:&quot;shave&quot;}]}
+/// {&quot;timestamp&quot;:&quot;2022-02-15T18:47:10.821598Z&quot;,&quot;level&quot;:&quot;DEBUG&quot;,&quot;fields&quot;:{&quot;yak&quot;:1,&quot;shaved&quot;:true},&quot;target&quot;:&quot;yak_events&quot;,&quot;spans&quot;:[{&quot;yaks&quot;:3,&quot;name&quot;:&quot;shaving_yaks&quot;}]}
+/// {&quot;timestamp&quot;:&quot;2022-02-15T18:47:10.821637Z&quot;,&quot;level&quot;:&quot;TRACE&quot;,&quot;fields&quot;:{&quot;yaks_shaved&quot;:1},&quot;target&quot;:&quot;fmt_json::yak_shave&quot;,&quot;spans&quot;:[{&quot;yaks&quot;:3,&quot;name&quot;:&quot;shaving_yaks&quot;}]}
+/// {&quot;timestamp&quot;:&quot;2022-02-15T18:47:10.821684Z&quot;,&quot;level&quot;:&quot;TRACE&quot;,&quot;fields&quot;:{&quot;message&quot;:&quot;hello! I&apos;m gonna shave a yak&quot;,&quot;excitement&quot;:&quot;yay!&quot;},&quot;target&quot;:&quot;fmt_json::yak_shave&quot;,&quot;spans&quot;:[{&quot;yaks&quot;:3,&quot;name&quot;:&quot;shaving_yaks&quot;},{&quot;yak&quot;:2,&quot;name&quot;:&quot;shave&quot;}]}
+/// {&quot;timestamp&quot;:&quot;2022-02-15T18:47:10.821727Z&quot;,&quot;level&quot;:&quot;TRACE&quot;,&quot;fields&quot;:{&quot;message&quot;:&quot;yak shaved successfully&quot;},&quot;target&quot;:&quot;fmt_json::yak_shave&quot;,&quot;spans&quot;:[{&quot;yaks&quot;:3,&quot;name&quot;:&quot;shaving_yaks&quot;},{&quot;yak&quot;:2,&quot;name&quot;:&quot;shave&quot;}]}
+/// {&quot;timestamp&quot;:&quot;2022-02-15T18:47:10.821773Z&quot;,&quot;level&quot;:&quot;DEBUG&quot;,&quot;fields&quot;:{&quot;yak&quot;:2,&quot;shaved&quot;:true},&quot;target&quot;:&quot;yak_events&quot;,&quot;spans&quot;:[{&quot;yaks&quot;:3,&quot;name&quot;:&quot;shaving_yaks&quot;}]}
+/// {&quot;timestamp&quot;:&quot;2022-02-15T18:47:10.821806Z&quot;,&quot;level&quot;:&quot;TRACE&quot;,&quot;fields&quot;:{&quot;yaks_shaved&quot;:2},&quot;target&quot;:&quot;fmt_json::yak_shave&quot;,&quot;spans&quot;:[{&quot;yaks&quot;:3,&quot;name&quot;:&quot;shaving_yaks&quot;}]}
+/// {&quot;timestamp&quot;:&quot;2022-02-15T18:47:10.821909Z&quot;,&quot;level&quot;:&quot;TRACE&quot;,&quot;fields&quot;:{&quot;message&quot;:&quot;hello! I&apos;m gonna shave a yak&quot;,&quot;excitement&quot;:&quot;yay!&quot;},&quot;target&quot;:&quot;fmt_json::yak_shave&quot;,&quot;spans&quot;:[{&quot;yaks&quot;:3,&quot;name&quot;:&quot;shaving_yaks&quot;},{&quot;yak&quot;:3,&quot;name&quot;:&quot;shave&quot;}]}
+/// {&quot;timestamp&quot;:&quot;2022-02-15T18:47:10.821956Z&quot;,&quot;level&quot;:&quot;WARN&quot;,&quot;fields&quot;:{&quot;message&quot;:&quot;could not locate yak&quot;},&quot;target&quot;:&quot;fmt_json::yak_shave&quot;,&quot;spans&quot;:[{&quot;yaks&quot;:3,&quot;name&quot;:&quot;shaving_yaks&quot;},{&quot;yak&quot;:3,&quot;name&quot;:&quot;shave&quot;}]}
+/// {&quot;timestamp&quot;:&quot;2022-02-15T18:47:10.822006Z&quot;,&quot;level&quot;:&quot;DEBUG&quot;,&quot;fields&quot;:{&quot;yak&quot;:3,&quot;shaved&quot;:false},&quot;target&quot;:&quot;yak_events&quot;,&quot;spans&quot;:[{&quot;yaks&quot;:3,&quot;name&quot;:&quot;shaving_yaks&quot;}]}
+/// {&quot;timestamp&quot;:&quot;2022-02-15T18:47:10.822041Z&quot;,&quot;level&quot;:&quot;ERROR&quot;,&quot;fields&quot;:{&quot;message&quot;:&quot;failed to shave yak&quot;,&quot;yak&quot;:3,&quot;error&quot;:&quot;missing yak&quot;},&quot;target&quot;:&quot;fmt_json::yak_shave&quot;,&quot;spans&quot;:[{&quot;yaks&quot;:3,&quot;name&quot;:&quot;shaving_yaks&quot;}]}
+/// {&quot;timestamp&quot;:&quot;2022-02-15T18:47:10.822079Z&quot;,&quot;level&quot;:&quot;TRACE&quot;,&quot;fields&quot;:{&quot;yaks_shaved&quot;:2},&quot;target&quot;:&quot;fmt_json::yak_shave&quot;,&quot;spans&quot;:[{&quot;yaks&quot;:3,&quot;name&quot;:&quot;shaving_yaks&quot;}]}
+/// {&quot;timestamp&quot;:&quot;2022-02-15T18:47:10.822117Z&quot;,&quot;level&quot;:&quot;INFO&quot;,&quot;fields&quot;:{&quot;message&quot;:&quot;yak shaving completed&quot;,&quot;all_yaks_shaved&quot;:false},&quot;target&quot;:&quot;fmt_json&quot;}
+/// </pre>
 ///
 /// # Options
 ///
+/// This formatter exposes additional options to configure the structure of the
+/// output JSON objects:
+///
 /// - [`Json::flatten_event`] can be used to enable flattening event fields into
 /// the root
 /// - [`Json::with_current_span`] can be used to control logging of the current
@@ -52,9 +69,23 @@ use tracing_log::NormalizeEvent;
 /// By default, event fields are not flattened, and both current span and span
 /// list are logged.
 ///
-/// [`Json::flatten_event`]: #method.flatten_event
-/// [`Json::with_current_span`]: #method.with_current_span
-/// [`Json::with_span_list`]: #method.with_span_list
+/// # Valuable Support
+///
+/// Experimental support is available for using the [`valuable`] crate to record
+/// user-defined values as structured JSON. When the ["valuable" unstable
+/// feature][unstable] is enabled, types implementing [`valuable::Valuable`] will
+/// be recorded as structured JSON, rather than
+/// using their [`std::fmt::Debug`] implementations.
+///
+/// **Note**: This is an experimental feature. [Unstable features][unstable]
+/// must be enabled in order to use `valuable` support.
+///
+/// [`Json::flatten_event`]: Json::flatten_event()
+/// [`Json::with_current_span`]: Json::with_current_span()
+/// [`Json::with_span_list`]: Json::with_span_list()
+/// [`valuable`]: https://crates.io/crates/valuable
+/// [unstable]: crate#unstable-features
+/// [`valuable::Valuable`]: https://docs.rs/valuable/latest/valuable/trait.Valuable.html
 #[derive(Debug, Copy, Clone, Eq, PartialEq)]
 pub struct Json {
     pub(crate) flatten_event: bool,
@@ -243,6 +274,18 @@ where
                 serializer.serialize_entry("target", meta.target())?;
             }
 
+            if self.display_filename {
+                if let Some(filename) = meta.file() {
+                    serializer.serialize_entry("filename", filename)?;
+                }
+            }
+
+            if self.display_line_number {
+                if let Some(line_number) = meta.line() {
+                    serializer.serialize_entry("line_number", &line_number)?;
+                }
+            }
+
             if self.format.display_current_span {
                 if let Some(ref span) = current_span {
                     serializer
@@ -298,7 +341,6 @@ impl Default for Json {
 
 /// The JSON [`FormatFields`] implementation.
 ///
-/// [`FormatFields`]: trait.FormatFields.html
 #[derive(Debug)]
 pub struct JsonFields {
     // reserve the ability to add fields to this without causing a breaking
@@ -309,7 +351,6 @@ pub struct JsonFields {
 impl JsonFields {
     /// Returns a new JSON [`FormatFields`] implementation.
     ///
-    /// [`FormatFields`]: trait.FormatFields.html
     pub fn new() -> Self {
         Self { _private: () }
     }
@@ -378,9 +419,8 @@ impl<'a> FormatFields<'a> for JsonFields {
 
 /// The [visitor] produced by [`JsonFields`]'s [`MakeVisitor`] implementation.
 ///
-/// [visitor]: ../../field/trait.Visit.html
-/// [`JsonFields`]: struct.JsonFields.html
-/// [`MakeVisitor`]: ../../field/trait.MakeVisitor.html
+/// [visitor]: crate::field::Visit
+/// [`MakeVisitor`]: crate::field::MakeVisitor
 pub struct JsonVisitor<'a> {
     values: BTreeMap<&'a str, serde_json::Value>,
     writer: &'a mut dyn Write,
@@ -435,6 +475,26 @@ impl<'a> crate::field::VisitOutput<fmt::Result> for JsonVisitor<'a> {
 }
 
 impl<'a> field::Visit for JsonVisitor<'a> {
+    #[cfg(all(tracing_unstable, feature = "valuable"))]
+    fn record_value(&mut self, field: &Field, value: valuable_crate::Value<'_>) {
+        let value = match serde_json::to_value(valuable_serde::Serializable::new(value)) {
+            Ok(value) => value,
+            Err(_e) => {
+                #[cfg(debug_assertions)]
+                unreachable!(
+                    "`valuable::Valuable` implementations should always serialize \
+                    successfully, but an error occurred: {}",
+                    _e,
+                );
+
+                #[cfg(not(debug_assertions))]
+                return;
+            }
+        };
+
+        self.values.insert(field.name(), value);
+    }
+
     /// Visit a double precision floating point value.
     fn record_f64(&mut self, field: &Field, value: f64) {
         self.values
@@ -488,6 +548,7 @@ mod test {
     use tracing::{self, subscriber::with_default};
 
     use std::fmt;
+    use std::path::Path;
 
     struct MockTime;
     impl FormatTime for MockTime {
@@ -516,6 +577,50 @@ mod test {
     }
 
     #[test]
+    fn json_filename() {
+        let current_path = Path::new("tracing-subscriber")
+            .join("src")
+            .join("fmt")
+            .join("format")
+            .join("json.rs")
+            .to_str()
+            .expect("path must be valid unicode")
+            // escape windows backslashes
+            .replace('\\', "\\\\");
+        let expected =
+            &format!("{}{}{}",
+                    "{\"timestamp\":\"fake time\",\"level\":\"INFO\",\"span\":{\"answer\":42,\"name\":\"json_span\",\"number\":3},\"spans\":[{\"answer\":42,\"name\":\"json_span\",\"number\":3}],\"target\":\"tracing_subscriber::fmt::format::json::test\",\"filename\":\"",
+                    current_path,
+                    "\",\"fields\":{\"message\":\"some json test\"}}\n");
+        let subscriber = subscriber()
+            .flatten_event(false)
+            .with_current_span(true)
+            .with_file(true)
+            .with_span_list(true);
+        test_json(expected, subscriber, || {
+            let span = tracing::span!(tracing::Level::INFO, "json_span", answer = 42, number = 3);
+            let _guard = span.enter();
+            tracing::info!("some json test");
+        });
+    }
+
+    #[test]
+    fn json_line_number() {
+        let expected =
+            "{\"timestamp\":\"fake time\",\"level\":\"INFO\",\"span\":{\"answer\":42,\"name\":\"json_span\",\"number\":3},\"spans\":[{\"answer\":42,\"name\":\"json_span\",\"number\":3}],\"target\":\"tracing_subscriber::fmt::format::json::test\",\"line_number\":42,\"fields\":{\"message\":\"some json test\"}}\n";
+        let subscriber = subscriber()
+            .flatten_event(false)
+            .with_current_span(true)
+            .with_line_number(true)
+            .with_span_list(true);
+        test_json_with_line_number(expected, subscriber, || {
+            let span = tracing::span!(tracing::Level::INFO, "json_span", answer = 42, number = 3);
+            let _guard = span.enter();
+            tracing::info!("some json test");
+        });
+    }
+
+    #[test]
     fn json_flattened_event() {
         let expected =
         "{\"timestamp\":\"fake time\",\"level\":\"INFO\",\"span\":{\"answer\":42,\"name\":\"json_span\",\"number\":3},\"spans\":[{\"answer\":42,\"name\":\"json_span\",\"number\":3}],\"target\":\"tracing_subscriber::fmt::format::json::test\",\"message\":\"some json test\"}\n";
@@ -747,4 +852,34 @@ mod test {
             serde_json::from_str(actual).unwrap()
         );
     }
+
+    fn test_json_with_line_number<T>(
+        expected: &str,
+        builder: crate::fmt::SubscriberBuilder<JsonFields, Format<Json>>,
+        producer: impl FnOnce() -> T,
+    ) {
+        let make_writer = MockMakeWriter::default();
+        let subscriber = builder
+            .with_writer(make_writer.clone())
+            .with_timer(MockTime)
+            .finish();
+
+        with_default(subscriber, producer);
+
+        let buf = make_writer.buf();
+        let actual = std::str::from_utf8(&buf[..]).unwrap();
+        let mut expected =
+            serde_json::from_str::<std::collections::HashMap<&str, serde_json::Value>>(expected)
+                .unwrap();
+        let expect_line_number = expected.remove("line_number").is_some();
+        let mut actual: std::collections::HashMap<&str, serde_json::Value> =
+            serde_json::from_str(actual).unwrap();
+        let line_number = actual.remove("line_number");
+        if expect_line_number {
+            assert_eq!(line_number.map(|x| x.is_number()), Some(true));
+        } else {
+            assert!(line_number.is_none());
+        }
+        assert_eq!(actual, expected);
+    }
 }
diff --git a/vendor/tracing-subscriber-0.3.3/src/fmt/format/mod.rs b/vendor/tracing-subscriber/src/fmt/format/mod.rs
index 9001e102e..b8a482e55 100644
--- a/vendor/tracing-subscriber-0.3.3/src/fmt/format/mod.rs
+++ b/vendor/tracing-subscriber/src/fmt/format/mod.rs
@@ -1,4 +1,33 @@
 //! Formatters for logging `tracing` events.
+//!
+//! This module provides several formatter implementations, as well as utilities
+//! for implementing custom formatters.
+//!
+//! # Formatters
+//! This module provides a number of formatter implementations:
+//!
+//! * [`Full`]: The default formatter. This emits human-readable,
+//!   single-line logs for each event that occurs, with the current span context
+//!   displayed before the formatted representation of the event. See
+//!   [here](Full#example-output) for sample output.
+//!
+//! * [`Compact`]: A variant of the default formatter, optimized for
+//!   short line lengths. Fields from the current span context are appended to
+//!   the fields of the formatted event, and span names are not shown; the
+//!   verbosity level is abbreviated to a single character. See
+//!   [here](Compact#example-output) for sample output.
+//!
+//! * [`Pretty`]: Emits excessively pretty, multi-line logs, optimized
+//!   for human readability. This is primarily intended to be used in local
+//!   development and debugging, or for command-line applications, where
+//!   automated analysis and compact storage of logs is less of a priority than
+//!   readability and visual appeal. See [here](Pretty#example-output)
+//!   for sample output.
+//!
+//! * [`Json`]: Outputs newline-delimited JSON logs. This is intended
+//!   for production use with systems where structured logs are consumed as JSON
+//!   by analysis and viewing tools. The JSON output is not optimized for human
+//!   readability. See [here](Json#example-output) for sample output.
 use super::time::{FormatTime, SystemTime};
 use crate::{
     field::{MakeOutput, MakeVisitor, RecordFields, VisitFmt, VisitOutput},
@@ -17,7 +46,7 @@ use tracing_core::{
 use tracing_log::NormalizeEvent;
 
 #[cfg(feature = "ansi")]
-use ansi_term::{Colour, Style};
+use nu_ansi_term::{Color, Style};
 
 #[cfg(feature = "json")]
 mod json;
@@ -72,7 +101,7 @@ pub use pretty::*;
 ///   does not support ANSI escape codes (such as a log file), and they should
 ///   not be emitted.
 ///
-///   Crates like [`ansi_term`] and [`owo-colors`] can be used to add ANSI
+///   Crates like [`nu_ansi_term`] and [`owo-colors`] can be used to add ANSI
 ///   escape codes to formatted output.
 ///
 /// * The actual [`Event`] to be formatted.
@@ -153,13 +182,14 @@ pub use pretty::*;
 /// DEBUG yak_shaving::shaver: some-span{field-on-span=foo}: started shaving yak
 /// ```
 ///
+/// [`layer::Context`]: crate::layer::Context
 /// [`fmt::Layer`]: super::Layer
 /// [`fmt::Subscriber`]: super::Subscriber
 /// [`Event`]: tracing::Event
 /// [implements `FormatFields`]: super::FmtContext#impl-FormatFields<'writer>
 /// [ANSI terminal escape codes]: https://en.wikipedia.org/wiki/ANSI_escape_code
 /// [`Writer::has_ansi_escapes`]: Writer::has_ansi_escapes
-/// [`ansi_term`]: https://crates.io/crates/ansi_term
+/// [`nu_ansi_term`]: https://crates.io/crates/nu_ansi_term
 /// [`owo-colors`]: https://crates.io/crates/owo-colors
 /// [default formatter]: Full
 pub trait FormatEvent<S, N>
@@ -197,8 +227,8 @@ where
 /// time a span or event with fields is recorded, the subscriber will format
 /// those fields with its associated `FormatFields` implementation.
 ///
-/// [set of fields]: ../field/trait.RecordFields.html
-/// [`FmtSubscriber`]: ../fmt/struct.Subscriber.html
+/// [set of fields]: crate::field::RecordFields
+/// [`FmtSubscriber`]: super::Subscriber
 pub trait FormatFields<'writer> {
     /// Format the provided `fields` to the provided [`Writer`], returning a result.
     fn format_fields<R: RecordFields>(&self, writer: Writer<'writer>, fields: R) -> fmt::Result;
@@ -251,7 +281,6 @@ pub fn json() -> Format<Json> {
 /// Returns a [`FormatFields`] implementation that formats fields using the
 /// provided function or closure.
 ///
-/// [`FormatFields`]: trait.FormatFields.html
 pub fn debug_fn<F>(f: F) -> FieldFn<F>
 where
     F: Fn(&mut Writer<'_>, &Field, &dyn fmt::Debug) -> fmt::Result + Clone,
@@ -272,6 +301,8 @@ where
 ///
 /// Additionally, a `Writer` may expose additional `tracing`-specific
 /// information to the formatter implementation.
+///
+/// [fields]: tracing_core::field
 pub struct Writer<'writer> {
     writer: &'writer mut dyn fmt::Write,
     // TODO(eliza): add ANSI support
@@ -281,28 +312,76 @@ pub struct Writer<'writer> {
 /// A [`FormatFields`] implementation that formats fields by calling a function
 /// or closure.
 ///
-/// [`FormatFields`]: trait.FormatFields.html
 #[derive(Debug, Clone)]
 pub struct FieldFn<F>(F);
 /// The [visitor] produced by [`FieldFn`]'s [`MakeVisitor`] implementation.
 ///
-/// [visitor]: ../../field/trait.Visit.html
-/// [`FieldFn`]: struct.FieldFn.html
-/// [`MakeVisitor`]: ../../field/trait.MakeVisitor.html
+/// [visitor]: super::super::field::Visit
+/// [`MakeVisitor`]: super::super::field::MakeVisitor
 pub struct FieldFnVisitor<'a, F> {
     f: F,
     writer: Writer<'a>,
     result: fmt::Result,
 }
-/// Marker for `Format` that indicates that the compact log format should be used.
+/// Marker for [`Format`] that indicates that the compact log format should be used.
+///
+/// The compact format includes fields from all currently entered spans, after
+/// the event's fields. Span names are listed in order before fields are
+/// displayed.
+///
+/// # Example Output
 ///
-/// The compact format only includes the fields from the most recently entered span.
+/// <pre><font color="#4E9A06"><b>:;</b></font> <font color="#4E9A06">cargo</font> run --example fmt-compact
+/// <font color="#4E9A06"><b>    Finished</b></font> dev [unoptimized + debuginfo] target(s) in 0.08s
+/// <font color="#4E9A06"><b>     Running</b></font> `target/debug/examples/fmt-compact`
+/// <font color="#AAAAAA">2022-02-17T19:51:05.809287Z </font><font color="#4E9A06"> INFO</font> <b>fmt_compact</b><font color="#AAAAAA">: preparing to shave yaks </font><i>number_of_yaks</i><font color="#AAAAAA">=3</font>
+/// <font color="#AAAAAA">2022-02-17T19:51:05.809367Z </font><font color="#4E9A06"> INFO</font> <b>shaving_yaks</b>: <b>fmt_compact::yak_shave</b><font color="#AAAAAA">: shaving yaks </font><font color="#AAAAAA"><i>yaks</i></font><font color="#AAAAAA">=3</font>
+/// <font color="#AAAAAA">2022-02-17T19:51:05.809414Z </font><font color="#75507B">TRACE</font> <b>shaving_yaks</b>:<b>shave</b>: <b>fmt_compact::yak_shave</b><font color="#AAAAAA">: hello! I&apos;m gonna shave a yak </font><i>excitement</i><font color="#AAAAAA">=&quot;yay!&quot; </font><font color="#AAAAAA"><i>yaks</i></font><font color="#AAAAAA">=3 </font><font color="#AAAAAA"><i>yak</i></font><font color="#AAAAAA">=1</font>
+/// <font color="#AAAAAA">2022-02-17T19:51:05.809443Z </font><font color="#75507B">TRACE</font> <b>shaving_yaks</b>:<b>shave</b>: <b>fmt_compact::yak_shave</b><font color="#AAAAAA">: yak shaved successfully </font><font color="#AAAAAA"><i>yaks</i></font><font color="#AAAAAA">=3 </font><font color="#AAAAAA"><i>yak</i></font><font color="#AAAAAA">=1</font>
+/// <font color="#AAAAAA">2022-02-17T19:51:05.809477Z </font><font color="#3465A4">DEBUG</font> <b>shaving_yaks</b>: <b>yak_events</b><font color="#AAAAAA">: </font><i>yak</i><font color="#AAAAAA">=1 </font><i>shaved</i><font color="#AAAAAA">=true </font><font color="#AAAAAA"><i>yaks</i></font><font color="#AAAAAA">=3</font>
+/// <font color="#AAAAAA">2022-02-17T19:51:05.809500Z </font><font color="#75507B">TRACE</font> <b>shaving_yaks</b>: <b>fmt_compact::yak_shave</b><font color="#AAAAAA">: </font><i>yaks_shaved</i><font color="#AAAAAA">=1 </font><font color="#AAAAAA"><i>yaks</i></font><font color="#AAAAAA">=3</font>
+/// <font color="#AAAAAA">2022-02-17T19:51:05.809531Z </font><font color="#75507B">TRACE</font> <b>shaving_yaks</b>:<b>shave</b>: <b>fmt_compact::yak_shave</b><font color="#AAAAAA">: hello! I&apos;m gonna shave a yak </font><i>excitement</i><font color="#AAAAAA">=&quot;yay!&quot; </font><font color="#AAAAAA"><i>yaks</i></font><font color="#AAAAAA">=3 </font><font color="#AAAAAA"><i>yak</i></font><font color="#AAAAAA">=2</font>
+/// <font color="#AAAAAA">2022-02-17T19:51:05.809554Z </font><font color="#75507B">TRACE</font> <b>shaving_yaks</b>:<b>shave</b>: <b>fmt_compact::yak_shave</b><font color="#AAAAAA">: yak shaved successfully </font><font color="#AAAAAA"><i>yaks</i></font><font color="#AAAAAA">=3 </font><font color="#AAAAAA"><i>yak</i></font><font color="#AAAAAA">=2</font>
+/// <font color="#AAAAAA">2022-02-17T19:51:05.809581Z </font><font color="#3465A4">DEBUG</font> <b>shaving_yaks</b>: <b>yak_events</b><font color="#AAAAAA">: </font><i>yak</i><font color="#AAAAAA">=2 </font><i>shaved</i><font color="#AAAAAA">=true </font><font color="#AAAAAA"><i>yaks</i></font><font color="#AAAAAA">=3</font>
+/// <font color="#AAAAAA">2022-02-17T19:51:05.809606Z </font><font color="#75507B">TRACE</font> <b>shaving_yaks</b>: <b>fmt_compact::yak_shave</b><font color="#AAAAAA">: </font><i>yaks_shaved</i><font color="#AAAAAA">=2 </font><font color="#AAAAAA"><i>yaks</i></font><font color="#AAAAAA">=3</font>
+/// <font color="#AAAAAA">2022-02-17T19:51:05.809635Z </font><font color="#75507B">TRACE</font> <b>shaving_yaks</b>:<b>shave</b>: <b>fmt_compact::yak_shave</b><font color="#AAAAAA">: hello! I&apos;m gonna shave a yak </font><i>excitement</i><font color="#AAAAAA">=&quot;yay!&quot; </font><font color="#AAAAAA"><i>yaks</i></font><font color="#AAAAAA">=3 </font><font color="#AAAAAA"><i>yak</i></font><font color="#AAAAAA">=3</font>
+/// <font color="#AAAAAA">2022-02-17T19:51:05.809664Z </font><font color="#C4A000"> WARN</font> <b>shaving_yaks</b>:<b>shave</b>: <b>fmt_compact::yak_shave</b><font color="#AAAAAA">: could not locate yak </font><font color="#AAAAAA"><i>yaks</i></font><font color="#AAAAAA">=3 </font><font color="#AAAAAA"><i>yak</i></font><font color="#AAAAAA">=3</font>
+/// <font color="#AAAAAA">2022-02-17T19:51:05.809693Z </font><font color="#3465A4">DEBUG</font> <b>shaving_yaks</b>: <b>yak_events</b><font color="#AAAAAA">: </font><i>yak</i><font color="#AAAAAA">=3 </font><i>shaved</i><font color="#AAAAAA">=false </font><font color="#AAAAAA"><i>yaks</i></font><font color="#AAAAAA">=3</font>
+/// <font color="#AAAAAA">2022-02-17T19:51:05.809717Z </font><font color="#CC0000">ERROR</font> <b>shaving_yaks</b>: <b>fmt_compact::yak_shave</b><font color="#AAAAAA">: failed to shave yak </font><i>yak</i><font color="#AAAAAA">=3 </font><i>error</i><font color="#AAAAAA">=missing yak </font><i>error.sources</i><font color="#AAAAAA">=[out of space, out of cash] </font><font color="#AAAAAA"><i>yaks</i></font><font color="#AAAAAA">=3</font>
+/// <font color="#AAAAAA">2022-02-17T19:51:05.809743Z </font><font color="#75507B">TRACE</font> <b>shaving_yaks</b>: <b>fmt_compact::yak_shave</b><font color="#AAAAAA">: </font><i>yaks_shaved</i><font color="#AAAAAA">=2 </font><font color="#AAAAAA"><i>yaks</i></font><font color="#AAAAAA">=3</font>
+/// <font color="#AAAAAA">2022-02-17T19:51:05.809768Z </font><font color="#4E9A06"> INFO</font> <b>fmt_compact</b><font color="#AAAAAA">: yak shaving completed </font><i>all_yaks_shaved</i><font color="#AAAAAA">=false</font>
+///
+/// </pre>
 #[derive(Default, Debug, Copy, Clone, Eq, PartialEq)]
 pub struct Compact;
 
-/// Marker for `Format` that indicates that the verbose log format should be used.
+/// Marker for [`Format`] that indicates that the default log format should be used.
+///
+/// This formatter shows the span context before printing event data. Spans are
+/// displayed including their names and fields.
 ///
-/// The full format includes fields from all entered spans.
+/// # Example Output
+///
+/// <pre><font color="#4E9A06"><b>:;</b></font> <font color="#4E9A06">cargo</font> run --example fmt
+/// <font color="#4E9A06"><b>    Finished</b></font> dev [unoptimized + debuginfo] target(s) in 0.08s
+/// <font color="#4E9A06"><b>     Running</b></font> `target/debug/examples/fmt`
+/// <font color="#AAAAAA">2022-02-15T18:40:14.289898Z </font><font color="#4E9A06"> INFO</font> fmt: preparing to shave yaks <i>number_of_yaks</i><font color="#AAAAAA">=3</font>
+/// <font color="#AAAAAA">2022-02-15T18:40:14.289974Z </font><font color="#4E9A06"> INFO</font> <b>shaving_yaks{</b><i>yaks</i><font color="#AAAAAA">=3</font><b>}</b><font color="#AAAAAA">: fmt::yak_shave: shaving yaks</font>
+/// <font color="#AAAAAA">2022-02-15T18:40:14.290011Z </font><font color="#75507B">TRACE</font> <b>shaving_yaks{</b><i>yaks</i><font color="#AAAAAA">=3</font><b>}</b><font color="#AAAAAA">:</font><b>shave{</b><i>yak</i><font color="#AAAAAA">=1</font><b>}</b><font color="#AAAAAA">: fmt::yak_shave: hello! I&apos;m gonna shave a yak </font><i>excitement</i><font color="#AAAAAA">=&quot;yay!&quot;</font>
+/// <font color="#AAAAAA">2022-02-15T18:40:14.290038Z </font><font color="#75507B">TRACE</font> <b>shaving_yaks{</b><i>yaks</i><font color="#AAAAAA">=3</font><b>}</b><font color="#AAAAAA">:</font><b>shave{</b><i>yak</i><font color="#AAAAAA">=1</font><b>}</b><font color="#AAAAAA">: fmt::yak_shave: yak shaved successfully</font>
+/// <font color="#AAAAAA">2022-02-15T18:40:14.290070Z </font><font color="#3465A4">DEBUG</font> <b>shaving_yaks{</b><i>yaks</i><font color="#AAAAAA">=3</font><b>}</b><font color="#AAAAAA">: yak_events: </font><i>yak</i><font color="#AAAAAA">=1 </font><i>shaved</i><font color="#AAAAAA">=true</font>
+/// <font color="#AAAAAA">2022-02-15T18:40:14.290089Z </font><font color="#75507B">TRACE</font> <b>shaving_yaks{</b><i>yaks</i><font color="#AAAAAA">=3</font><b>}</b><font color="#AAAAAA">: fmt::yak_shave: </font><i>yaks_shaved</i><font color="#AAAAAA">=1</font>
+/// <font color="#AAAAAA">2022-02-15T18:40:14.290114Z </font><font color="#75507B">TRACE</font> <b>shaving_yaks{</b><i>yaks</i><font color="#AAAAAA">=3</font><b>}</b><font color="#AAAAAA">:</font><b>shave{</b><i>yak</i><font color="#AAAAAA">=2</font><b>}</b><font color="#AAAAAA">: fmt::yak_shave: hello! I&apos;m gonna shave a yak </font><i>excitement</i><font color="#AAAAAA">=&quot;yay!&quot;</font>
+/// <font color="#AAAAAA">2022-02-15T18:40:14.290134Z </font><font color="#75507B">TRACE</font> <b>shaving_yaks{</b><i>yaks</i><font color="#AAAAAA">=3</font><b>}</b><font color="#AAAAAA">:</font><b>shave{</b><i>yak</i><font color="#AAAAAA">=2</font><b>}</b><font color="#AAAAAA">: fmt::yak_shave: yak shaved successfully</font>
+/// <font color="#AAAAAA">2022-02-15T18:40:14.290157Z </font><font color="#3465A4">DEBUG</font> <b>shaving_yaks{</b><i>yaks</i><font color="#AAAAAA">=3</font><b>}</b><font color="#AAAAAA">: yak_events: </font><i>yak</i><font color="#AAAAAA">=2 </font><i>shaved</i><font color="#AAAAAA">=true</font>
+/// <font color="#AAAAAA">2022-02-15T18:40:14.290174Z </font><font color="#75507B">TRACE</font> <b>shaving_yaks{</b><i>yaks</i><font color="#AAAAAA">=3</font><b>}</b><font color="#AAAAAA">: fmt::yak_shave: </font><i>yaks_shaved</i><font color="#AAAAAA">=2</font>
+/// <font color="#AAAAAA">2022-02-15T18:40:14.290198Z </font><font color="#75507B">TRACE</font> <b>shaving_yaks{</b><i>yaks</i><font color="#AAAAAA">=3</font><b>}</b><font color="#AAAAAA">:</font><b>shave{</b><i>yak</i><font color="#AAAAAA">=3</font><b>}</b><font color="#AAAAAA">: fmt::yak_shave: hello! I&apos;m gonna shave a yak </font><i>excitement</i><font color="#AAAAAA">=&quot;yay!&quot;</font>
+/// <font color="#AAAAAA">2022-02-15T18:40:14.290222Z </font><font color="#C4A000"> WARN</font> <b>shaving_yaks{</b><i>yaks</i><font color="#AAAAAA">=3</font><b>}</b><font color="#AAAAAA">:</font><b>shave{</b><i>yak</i><font color="#AAAAAA">=3</font><b>}</b><font color="#AAAAAA">: fmt::yak_shave: could not locate yak</font>
+/// <font color="#AAAAAA">2022-02-15T18:40:14.290247Z </font><font color="#3465A4">DEBUG</font> <b>shaving_yaks{</b><i>yaks</i><font color="#AAAAAA">=3</font><b>}</b><font color="#AAAAAA">: yak_events: </font><i>yak</i><font color="#AAAAAA">=3 </font><i>shaved</i><font color="#AAAAAA">=false</font>
+/// <font color="#AAAAAA">2022-02-15T18:40:14.290268Z </font><font color="#CC0000">ERROR</font> <b>shaving_yaks{</b><i>yaks</i><font color="#AAAAAA">=3</font><b>}</b><font color="#AAAAAA">: fmt::yak_shave: failed to shave yak </font><i>yak</i><font color="#AAAAAA">=3 </font><i>error</i><font color="#AAAAAA">=missing yak </font><i>error.sources</i><font color="#AAAAAA">=[out of space, out of cash]</font>
+/// <font color="#AAAAAA">2022-02-15T18:40:14.290287Z </font><font color="#75507B">TRACE</font> <b>shaving_yaks{</b><i>yaks</i><font color="#AAAAAA">=3</font><b>}</b><font color="#AAAAAA">: fmt::yak_shave: </font><i>yaks_shaved</i><font color="#AAAAAA">=2</font>
+/// <font color="#AAAAAA">2022-02-15T18:40:14.290309Z </font><font color="#4E9A06"> INFO</font> fmt: yak shaving completed. <i>all_yaks_shaved</i><font color="#AAAAAA">=false</font>
+/// </pre>
 #[derive(Default, Debug, Copy, Clone, Eq, PartialEq)]
 pub struct Full;
 
@@ -311,8 +390,11 @@ pub struct Full;
 /// You will usually want to use this as the `FormatEvent` for a `FmtSubscriber`.
 ///
 /// The default logging format, [`Full`] includes all fields in each event and its containing
-/// spans. The [`Compact`] logging format includes only the fields from the most-recently-entered
-/// span.
+/// spans. The [`Compact`] logging format is intended to produce shorter log
+/// lines; it displays each event's fields, along with fields from the current
+/// span context, but other information is abbreviated. The [`Pretty`] logging
+/// format is an extra-verbose, multi-line human-readable logging format
+/// intended for use in development.
 #[derive(Debug, Clone)]
 pub struct Format<F = Full, T = SystemTime> {
     format: F,
@@ -323,6 +405,8 @@ pub struct Format<F = Full, T = SystemTime> {
     pub(crate) display_level: bool,
     pub(crate) display_thread_id: bool,
     pub(crate) display_thread_name: bool,
+    pub(crate) display_filename: bool,
+    pub(crate) display_line_number: bool,
 }
 
 // === impl Writer ===
@@ -499,6 +583,8 @@ impl Default for Format<Full, SystemTime> {
             display_level: true,
             display_thread_id: false,
             display_thread_name: false,
+            display_filename: false,
+            display_line_number: false,
         }
     }
 }
@@ -517,6 +603,8 @@ impl<F, T> Format<F, T> {
             display_level: self.display_level,
             display_thread_id: self.display_thread_id,
             display_thread_name: self.display_thread_name,
+            display_filename: self.display_filename,
+            display_line_number: self.display_line_number,
         }
     }
 
@@ -554,6 +642,8 @@ impl<F, T> Format<F, T> {
             display_level: self.display_level,
             display_thread_id: self.display_thread_id,
             display_thread_name: self.display_thread_name,
+            display_filename: true,
+            display_line_number: true,
         }
     }
 
@@ -571,8 +661,6 @@ impl<F, T> Format<F, T> {
     ///
     /// - [`Format::flatten_event`] can be used to enable flattening event fields into the root
     /// object.
-    ///
-    /// [`Format::flatten_event`]: #method.flatten_event
     #[cfg(feature = "json")]
     #[cfg_attr(docsrs, doc(cfg(feature = "json")))]
     pub fn json(self) -> Format<Json, T> {
@@ -585,6 +673,8 @@ impl<F, T> Format<F, T> {
             display_level: self.display_level,
             display_thread_id: self.display_thread_id,
             display_thread_name: self.display_thread_name,
+            display_filename: self.display_filename,
+            display_line_number: self.display_line_number,
         }
     }
 
@@ -612,6 +702,8 @@ impl<F, T> Format<F, T> {
             display_level: self.display_level,
             display_thread_id: self.display_thread_id,
             display_thread_name: self.display_thread_name,
+            display_filename: self.display_filename,
+            display_line_number: self.display_line_number,
         }
     }
 
@@ -626,6 +718,8 @@ impl<F, T> Format<F, T> {
             display_level: self.display_level,
             display_thread_id: self.display_thread_id,
             display_thread_name: self.display_thread_name,
+            display_filename: self.display_filename,
+            display_line_number: self.display_line_number,
         }
     }
 
@@ -654,9 +748,9 @@ impl<F, T> Format<F, T> {
     }
 
     /// Sets whether or not the [thread ID] of the current thread is displayed
-    /// when formatting events
+    /// when formatting events.
     ///
-    /// [thread ID]: https://doc.rust-lang.org/stable/std/thread/struct.ThreadId.html
+    /// [thread ID]: std::thread::ThreadId
     pub fn with_thread_ids(self, display_thread_id: bool) -> Format<F, T> {
         Format {
             display_thread_id,
@@ -665,9 +759,9 @@ impl<F, T> Format<F, T> {
     }
 
     /// Sets whether or not the [name] of the current thread is displayed
-    /// when formatting events
+    /// when formatting events.
     ///
-    /// [name]: https://doc.rust-lang.org/stable/std/thread/index.html#naming-threads
+    /// [name]: std::thread#naming-threads
     pub fn with_thread_names(self, display_thread_name: bool) -> Format<F, T> {
         Format {
             display_thread_name,
@@ -675,6 +769,38 @@ impl<F, T> Format<F, T> {
         }
     }
 
+    /// Sets whether or not an event's [source code file path][file] is
+    /// displayed.
+    ///
+    /// [file]: tracing_core::Metadata::file
+    pub fn with_file(self, display_filename: bool) -> Format<F, T> {
+        Format {
+            display_filename,
+            ..self
+        }
+    }
+
+    /// Sets whether or not an event's [source code line number][line] is
+    /// displayed.
+    ///
+    /// [line]: tracing_core::Metadata::line
+    pub fn with_line_number(self, display_line_number: bool) -> Format<F, T> {
+        Format {
+            display_line_number,
+            ..self
+        }
+    }
+
+    /// Sets whether or not the source code location from which an event
+    /// originated is displayed.
+    ///
+    /// This is equivalent to calling [`Format::with_file`] and
+    /// [`Format::with_line_number`] with the same value.
+    pub fn with_source_location(self, display_location: bool) -> Self {
+        self.with_line_number(display_location)
+            .with_file(display_location)
+    }
+
     #[inline]
     fn format_timestamp(&self, writer: &mut Writer<'_>) -> fmt::Result
     where
@@ -692,14 +818,24 @@ impl<F, T> Format<F, T> {
             if writer.has_ansi_escapes() {
                 let style = Style::new().dimmed();
                 write!(writer, "{}", style.prefix())?;
-                self.timer.format_time(writer)?;
+
+                // If getting the timestamp failed, don't bail --- only bail on
+                // formatting errors.
+                if self.timer.format_time(writer).is_err() {
+                    writer.write_str("<unknown time>")?;
+                }
+
                 write!(writer, "{} ", style.suffix())?;
                 return Ok(());
             }
         }
 
         // Otherwise, just format the timestamp without ANSI formatting.
-        self.timer.format_time(writer)?;
+        // If getting the timestamp failed, don't bail --- only bail on
+        // formatting errors.
+        if self.timer.format_time(writer).is_err() {
+            writer.write_str("<unknown time>")?;
+        }
         writer.write_char(' ')
     }
 }
@@ -714,7 +850,7 @@ impl<T> Format<Json, T> {
     /// ```ignore,json
     /// {"timestamp":"Feb 20 11:28:15.096","level":"INFO","target":"mycrate", "message":"some message", "key": "value"}
     /// ```
-    /// See [`Json`](../format/struct.Json.html).
+    /// See [`Json`][super::format::Json].
     #[cfg(feature = "json")]
     #[cfg_attr(docsrs, doc(cfg(feature = "json")))]
     pub fn flatten_event(mut self, flatten_event: bool) -> Format<Json, T> {
@@ -725,7 +861,7 @@ impl<T> Format<Json, T> {
     /// Sets whether or not the formatter will include the current span in
     /// formatted events.
     ///
-    /// See [`format::Json`](../fmt/format/struct.Json.html)
+    /// See [`format::Json`][Json]
     #[cfg(feature = "json")]
     #[cfg_attr(docsrs, doc(cfg(feature = "json")))]
     pub fn with_current_span(mut self, display_current_span: bool) -> Format<Json, T> {
@@ -736,7 +872,7 @@ impl<T> Format<Json, T> {
     /// Sets whether or not the formatter will include a list (from root to
     /// leaf) of all currently entered spans in formatted events.
     ///
-    /// See [`format::Json`](../fmt/format/struct.Json.html)
+    /// See [`format::Json`][Json]
     #[cfg(feature = "json")]
     #[cfg_attr(docsrs, doc(cfg(feature = "json")))]
     pub fn with_span_list(mut self, display_span_list: bool) -> Format<Json, T> {
@@ -840,6 +976,34 @@ where
             )?;
         }
 
+        let line_number = if self.display_line_number {
+            meta.line()
+        } else {
+            None
+        };
+
+        if self.display_filename {
+            if let Some(filename) = meta.file() {
+                write!(
+                    writer,
+                    "{}{}{}",
+                    dimmed.paint(filename),
+                    dimmed.paint(":"),
+                    if line_number.is_some() { "" } else { " " }
+                )?;
+            }
+        }
+
+        if let Some(line_number) = line_number {
+            write!(
+                writer,
+                "{}{}:{} ",
+                dimmed.prefix(),
+                line_number,
+                dimmed.suffix()
+            )?;
+        }
+
         ctx.format_fields(writer.by_ref(), event)?;
         writeln!(writer)
     }
@@ -918,23 +1082,49 @@ where
         };
         write!(writer, "{}", fmt_ctx)?;
 
+        let bold = writer.bold();
+        let dimmed = writer.dimmed();
+
+        let mut needs_space = false;
         if self.display_target {
-            write!(
-                writer,
-                "{}{} ",
-                writer.bold().paint(meta.target()),
-                writer.dimmed().paint(":")
-            )?;
+            write!(writer, "{}{}", bold.paint(meta.target()), dimmed.paint(":"))?;
+            needs_space = true;
+        }
+
+        if self.display_filename {
+            if let Some(filename) = meta.file() {
+                if self.display_target {
+                    writer.write_char(' ')?;
+                }
+                write!(writer, "{}{}", bold.paint(filename), dimmed.paint(":"))?;
+                needs_space = true;
+            }
+        }
+
+        if self.display_line_number {
+            if let Some(line_number) = meta.line() {
+                write!(
+                    writer,
+                    "{}{}{}{}",
+                    bold.prefix(),
+                    line_number,
+                    bold.suffix(),
+                    dimmed.paint(":")
+                )?;
+                needs_space = true;
+            }
+        }
+
+        if needs_space {
+            writer.write_char(' ')?;
         }
 
         ctx.format_fields(writer.by_ref(), event)?;
 
-        let dimmed = writer.dimmed();
         for span in ctx
             .event_scope()
             .into_iter()
-            .map(crate::registry::Scope::from_root)
-            .flatten()
+            .flat_map(crate::registry::Scope::from_root)
         {
             let exts = span.extensions();
             if let Some(fields) = exts.get::<FormattedFields<N>>() {
@@ -962,7 +1152,6 @@ where
 
 /// The default [`FormatFields`] implementation.
 ///
-/// [`FormatFields`]: trait.FormatFields.html
 #[derive(Debug)]
 pub struct DefaultFields {
     // reserve the ability to add fields to this without causing a breaking
@@ -984,7 +1173,6 @@ pub struct DefaultVisitor<'a> {
 impl DefaultFields {
     /// Returns a new default [`FormatFields`] implementation.
     ///
-    /// [`FormatFields`]: trait.FormatFields.html
     pub fn new() -> Self {
         Self { _private: () }
     }
@@ -1201,6 +1389,14 @@ impl Style {
     fn paint(&self, d: impl fmt::Display) -> impl fmt::Display {
         d
     }
+
+    fn prefix(&self) -> impl fmt::Display {
+        ""
+    }
+
+    fn suffix(&self) -> impl fmt::Display {
+        ""
+    }
 }
 
 struct FmtThreadName<'a> {
@@ -1288,11 +1484,11 @@ impl<'a> fmt::Display for FmtLevel<'a> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         if self.ansi {
             match *self.level {
-                Level::TRACE => write!(f, "{}", Colour::Purple.paint(TRACE_STR)),
-                Level::DEBUG => write!(f, "{}", Colour::Blue.paint(DEBUG_STR)),
-                Level::INFO => write!(f, "{}", Colour::Green.paint(INFO_STR)),
-                Level::WARN => write!(f, "{}", Colour::Yellow.paint(WARN_STR)),
-                Level::ERROR => write!(f, "{}", Colour::Red.paint(ERROR_STR)),
+                Level::TRACE => write!(f, "{}", Color::Purple.paint(TRACE_STR)),
+                Level::DEBUG => write!(f, "{}", Color::Blue.paint(DEBUG_STR)),
+                Level::INFO => write!(f, "{}", Color::Green.paint(INFO_STR)),
+                Level::WARN => write!(f, "{}", Color::Yellow.paint(WARN_STR)),
+                Level::ERROR => write!(f, "{}", Color::Red.paint(ERROR_STR)),
             }
         } else {
             match *self.level {
@@ -1366,7 +1562,7 @@ impl<'a, F> fmt::Debug for FieldFnVisitor<'a, F> {
 
 /// Configures what points in the span lifecycle are logged as events.
 ///
-/// See also [`with_span_events`](../struct.SubscriberBuilder.html#method.with_span_events).
+/// See also [`with_span_events`](super::SubscriberBuilder.html::with_span_events).
 #[derive(Clone, Eq, PartialEq, Ord, PartialOrd)]
 pub struct FmtSpan(u8);
 
@@ -1528,7 +1724,9 @@ pub(super) mod test {
     };
 
     use super::*;
-    use std::fmt;
+
+    use regex::Regex;
+    use std::{fmt, path::Path};
 
     pub(crate) struct MockTime;
     impl FormatTime for MockTime {
@@ -1550,7 +1748,7 @@ pub(super) mod test {
             .with_thread_names(false);
         #[cfg(feature = "ansi")]
         let subscriber = subscriber.with_ansi(false);
-        run_test(subscriber, make_writer, "hello\n")
+        assert_info_hello(subscriber, make_writer, "hello\n")
     }
 
     fn test_ansi<T>(
@@ -1598,6 +1796,124 @@ pub(super) mod test {
         run_test(subscriber, make_writer, expected);
     }
 
+    #[test]
+    fn with_line_number_and_file_name() {
+        let make_writer = MockMakeWriter::default();
+        let subscriber = crate::fmt::Subscriber::builder()
+            .with_writer(make_writer.clone())
+            .with_file(true)
+            .with_line_number(true)
+            .with_level(false)
+            .with_ansi(false)
+            .with_timer(MockTime);
+
+        let expected = Regex::new(&format!(
+            "^fake time tracing_subscriber::fmt::format::test: {}:[0-9]+: hello\n$",
+            current_path()
+                // if we're on Windows, the path might contain backslashes, which
+                // have to be escpaed before compiling the regex.
+                .replace('\\', "\\\\")
+        ))
+        .unwrap();
+        let _default = set_default(&subscriber.into());
+        tracing::info!("hello");
+        let res = make_writer.get_string();
+        assert!(expected.is_match(&res));
+    }
+
+    #[test]
+    fn with_line_number() {
+        let make_writer = MockMakeWriter::default();
+        let subscriber = crate::fmt::Subscriber::builder()
+            .with_writer(make_writer.clone())
+            .with_line_number(true)
+            .with_level(false)
+            .with_ansi(false)
+            .with_timer(MockTime);
+
+        let expected =
+            Regex::new("^fake time tracing_subscriber::fmt::format::test: [0-9]+: hello\n$")
+                .unwrap();
+        let _default = set_default(&subscriber.into());
+        tracing::info!("hello");
+        let res = make_writer.get_string();
+        assert!(expected.is_match(&res));
+    }
+
+    #[test]
+    fn with_filename() {
+        let make_writer = MockMakeWriter::default();
+        let subscriber = crate::fmt::Subscriber::builder()
+            .with_writer(make_writer.clone())
+            .with_file(true)
+            .with_level(false)
+            .with_ansi(false)
+            .with_timer(MockTime);
+        let expected = &format!(
+            "fake time tracing_subscriber::fmt::format::test: {}: hello\n",
+            current_path(),
+        );
+        assert_info_hello(subscriber, make_writer, expected);
+    }
+
+    #[test]
+    fn with_thread_ids() {
+        let make_writer = MockMakeWriter::default();
+        let subscriber = crate::fmt::Subscriber::builder()
+            .with_writer(make_writer.clone())
+            .with_thread_ids(true)
+            .with_ansi(false)
+            .with_timer(MockTime);
+        let expected =
+            "fake time  INFO ThreadId(NUMERIC) tracing_subscriber::fmt::format::test: hello\n";
+
+        assert_info_hello_ignore_numeric(subscriber, make_writer, expected);
+    }
+
+    #[test]
+    fn pretty_default() {
+        let make_writer = MockMakeWriter::default();
+        let subscriber = crate::fmt::Subscriber::builder()
+            .pretty()
+            .with_writer(make_writer.clone())
+            .with_ansi(false)
+            .with_timer(MockTime);
+        let expected = format!(
+            r#"  fake time  INFO tracing_subscriber::fmt::format::test: hello
+    at {}:NUMERIC
+
+"#,
+            file!()
+        );
+
+        assert_info_hello_ignore_numeric(subscriber, make_writer, &expected)
+    }
+
+    fn assert_info_hello(subscriber: impl Into<Dispatch>, buf: MockMakeWriter, expected: &str) {
+        let _default = set_default(&subscriber.into());
+        tracing::info!("hello");
+        let result = buf.get_string();
+
+        assert_eq!(expected, result)
+    }
+
+    // When numeric characters are used they often form a non-deterministic value as they usually represent things like a thread id or line number.
+    // This assert method should be used when non-deterministic numeric characters are present.
+    fn assert_info_hello_ignore_numeric(
+        subscriber: impl Into<Dispatch>,
+        buf: MockMakeWriter,
+        expected: &str,
+    ) {
+        let _default = set_default(&subscriber.into());
+        tracing::info!("hello");
+
+        let regex = Regex::new("[0-9]+").unwrap();
+        let result = buf.get_string();
+        let result_cleaned = regex.replace_all(&result, "NUMERIC");
+
+        assert_eq!(expected, result_cleaned)
+    }
+
     fn test_overridden_parents<T>(
         expected: &str,
         builder: crate::fmt::SubscriberBuilder<DefaultFields, Format<T>>,
@@ -1606,14 +1922,14 @@ pub(super) mod test {
         T: Send + Sync + 'static,
     {
         let make_writer = MockMakeWriter::default();
-        let collector = builder
+        let subscriber = builder
             .with_writer(make_writer.clone())
             .with_level(false)
             .with_ansi(false)
             .with_timer(MockTime)
             .finish();
 
-        with_default(collector, || {
+        with_default(subscriber, || {
             let span1 = tracing::info_span!("span1", span = 1);
             let span2 = tracing::info_span!(parent: &span1, "span2", span = 2);
             tracing::info!(parent: &span2, "hello");
@@ -1659,6 +1975,21 @@ pub(super) mod test {
 
     mod default {
         use super::*;
+
+        #[test]
+        fn with_thread_ids() {
+            let make_writer = MockMakeWriter::default();
+            let subscriber = crate::fmt::Subscriber::builder()
+                .with_writer(make_writer.clone())
+                .with_thread_ids(true)
+                .with_ansi(false)
+                .with_timer(MockTime);
+            let expected =
+                "fake time  INFO ThreadId(NUMERIC) tracing_subscriber::fmt::format::test: hello\n";
+
+            assert_info_hello_ignore_numeric(subscriber, make_writer, expected);
+        }
+
         #[cfg(feature = "ansi")]
         #[test]
         fn with_ansi_true() {
@@ -1748,6 +2079,26 @@ pub(super) mod test {
         }
     }
 
+    mod pretty {
+        use super::*;
+
+        #[test]
+        fn pretty_default() {
+            let make_writer = MockMakeWriter::default();
+            let subscriber = crate::fmt::Subscriber::builder()
+                .pretty()
+                .with_writer(make_writer.clone())
+                .with_ansi(false)
+                .with_timer(MockTime);
+            let expected = format!(
+                "  fake time  INFO tracing_subscriber::fmt::format::test: hello\n    at {}:NUMERIC\n\n",
+                file!()
+            );
+
+            assert_info_hello_ignore_numeric(subscriber, make_writer, &expected)
+        }
+    }
+
     #[test]
     fn format_nanos() {
         fn fmt(t: u64) -> String {
@@ -1795,4 +2146,16 @@ pub(super) mod test {
         assert!(!f.contains(FmtSpan::EXIT));
         assert!(f.contains(FmtSpan::CLOSE));
     }
+
+    /// Returns the test's module path.
+    fn current_path() -> String {
+        Path::new("tracing-subscriber")
+            .join("src")
+            .join("fmt")
+            .join("format")
+            .join("mod.rs")
+            .to_str()
+            .expect("path must not contain invalid unicode")
+            .to_owned()
+    }
 }
diff --git a/vendor/tracing-subscriber-0.3.3/src/fmt/mod.rs b/vendor/tracing-subscriber/src/fmt/mod.rs
index d5deb8f0c..025e17504 100644
--- a/vendor/tracing-subscriber-0.3.3/src/fmt/mod.rs
+++ b/vendor/tracing-subscriber/src/fmt/mod.rs
@@ -13,10 +13,12 @@
 //!
 //! ```toml
 //! [dependencies]
-//! tracing-subscriber = "0.2"
+//! tracing-subscriber = "0.3"
 //! ```
 //!
-//! *Compiler support: requires rustc 1.39+*
+//! *Compiler support: [requires `rustc` 1.49+][msrv]*
+//!
+//! [msrv]: super#supported-rust-versions
 //!
 //! Add the following to your executable to initialize the default subscriber:
 //! ```rust
@@ -68,132 +70,25 @@
 //!
 //! * [`format::Full`]: The default formatter. This emits human-readable,
 //!   single-line logs for each event that occurs, with the current span context
-//!   displayed before the formatted representation of the event.
+//!   displayed before the formatted representation of the event. See
+//!   [here](format::Full#example-output) for sample output.
 //!
-//!   For example:
-//!   <pre><font color="#4E9A06"><b>    Finished</b></font> dev [unoptimized + debuginfo] target(s) in 1.59s
-//!   <font color="#4E9A06"><b>     Running</b></font> `target/debug/examples/fmt`
-//!   <font color="#AAAAAA">Oct 24 12:55:47.814 </font><font color="#4E9A06"> INFO</font> fmt: preparing to shave yaks number_of_yaks=3
-//!   <font color="#AAAAAA">Oct 24 12:55:47.814 </font><font color="#4E9A06"> INFO</font> <b>shaving_yaks{</b>yaks=3<b>}</b>: fmt::yak_shave: shaving yaks
-//!   <font color="#AAAAAA">Oct 24 12:55:47.814 </font><font color="#75507B">TRACE</font> <b>shaving_yaks{</b>yaks=3<b>}</b>:<b>shave{</b>yak=1<b>}</b>: fmt::yak_shave: hello! I&apos;m gonna shave a yak excitement=&quot;yay!&quot;
-//!   <font color="#AAAAAA">Oct 24 12:55:47.814 </font><font color="#75507B">TRACE</font> <b>shaving_yaks{</b>yaks=3<b>}</b>:<b>shave{</b>yak=1<b>}</b>: fmt::yak_shave: yak shaved successfully
-//!   <font color="#AAAAAA">Oct 24 12:55:47.814 </font><font color="#3465A4">DEBUG</font> <b>shaving_yaks{</b>yaks=3<b>}</b>: yak_events: yak=1 shaved=true
-//!   <font color="#AAAAAA">Oct 24 12:55:47.814 </font><font color="#75507B">TRACE</font> <b>shaving_yaks{</b>yaks=3<b>}</b>: fmt::yak_shave: yaks_shaved=1
-//!   <font color="#AAAAAA">Oct 24 12:55:47.815 </font><font color="#75507B">TRACE</font> <b>shaving_yaks{</b>yaks=3<b>}</b>:<b>shave{</b>yak=2<b>}</b>: fmt::yak_shave: hello! I&apos;m gonna shave a yak excitement=&quot;yay!&quot;
-//!   <font color="#AAAAAA">Oct 24 12:55:47.815 </font><font color="#75507B">TRACE</font> <b>shaving_yaks{</b>yaks=3<b>}</b>:<b>shave{</b>yak=2<b>}</b>: fmt::yak_shave: yak shaved successfully
-//!   <font color="#AAAAAA">Oct 24 12:55:47.815 </font><font color="#3465A4">DEBUG</font> <b>shaving_yaks{</b>yaks=3<b>}</b>: yak_events: yak=2 shaved=true
-//!   <font color="#AAAAAA">Oct 24 12:55:47.815 </font><font color="#75507B">TRACE</font> <b>shaving_yaks{</b>yaks=3<b>}</b>: fmt::yak_shave: yaks_shaved=2
-//!   <font color="#AAAAAA">Oct 24 12:55:47.815 </font><font color="#75507B">TRACE</font> <b>shaving_yaks{</b>yaks=3<b>}</b>:<b>shave{</b>yak=3<b>}</b>: fmt::yak_shave: hello! I&apos;m gonna shave a yak excitement=&quot;yay!&quot;
-//!   <font color="#AAAAAA">Oct 24 12:55:47.815 </font><font color="#C4A000"> WARN</font> <b>shaving_yaks{</b>yaks=3<b>}</b>:<b>shave{</b>yak=3<b>}</b>: fmt::yak_shave: could not locate yak
-//!   <font color="#AAAAAA">Oct 24 12:55:47.815 </font><font color="#3465A4">DEBUG</font> <b>shaving_yaks{</b>yaks=3<b>}</b>: yak_events: yak=3 shaved=false
-//!   <font color="#AAAAAA">Oct 24 12:55:47.815 </font><font color="#CC0000">ERROR</font> <b>shaving_yaks{</b>yaks=3<b>}</b>: fmt::yak_shave: failed to shave yak yak=3 error=missing yak
-//!   <font color="#AAAAAA">Oct 24 12:55:47.815 </font><font color="#75507B">TRACE</font> <b>shaving_yaks{</b>yaks=3<b>}</b>: fmt::yak_shave: yaks_shaved=2
-//!   <font color="#AAAAAA">Oct 24 12:55:47.815 </font><font color="#4E9A06"> INFO</font> fmt: yak shaving completed all_yaks_shaved=false
-//!   </pre>
+//! * [`format::Compact`]: A variant of the default formatter, optimized for
+//!   short line lengths. Fields from the current span context are appended to
+//!   the fields of the formatted event. See
+//!   [here](format::Compact#example-output) for sample output.
 //!
 //! * [`format::Pretty`]: Emits excessively pretty, multi-line logs, optimized
 //!   for human readability. This is primarily intended to be used in local
 //!   development and debugging, or for command-line applications, where
 //!   automated analysis and compact storage of logs is less of a priority than
-//!   readability and visual appeal.
-//!
-//!   For example:
-//!   <pre><font color="#4E9A06"><b>    Finished</b></font> dev [unoptimized + debuginfo] target(s) in 1.61s
-//!   <font color="#4E9A06"><b>     Running</b></font> `target/debug/examples/fmt-pretty`
-//!   Oct 24 12:57:29.386 <font color="#4E9A06"><b>fmt_pretty</b></font><font color="#4E9A06">: preparing to shave yaks, </font><font color="#4E9A06"><b>number_of_yaks</b></font><font color="#4E9A06">: 3</font>
-//!     <font color="#AAAAAA"><i>at</i></font> examples/examples/fmt-pretty.rs:16<font color="#AAAAAA"><i> on</i></font> main
-//!
-//!   Oct 24 12:57:29.386 <font color="#4E9A06"><b>fmt_pretty::yak_shave</b></font><font color="#4E9A06">: shaving yaks</font>
-//!     <font color="#AAAAAA"><i>at</i></font> examples/examples/fmt/yak_shave.rs:38<font color="#AAAAAA"><i> on</i></font> main
-//!     <font color="#AAAAAA"><i>in</i></font> fmt_pretty::yak_shave::<b>shaving_yaks</b> <font color="#AAAAAA"><i>with</i></font> <b>yaks</b>: 3
-//!
-//!   Oct 24 12:57:29.387 <font color="#75507B"><b>fmt_pretty::yak_shave</b></font><font color="#75507B">: hello! I&apos;m gonna shave a yak, </font><font color="#75507B"><b>excitement</b></font><font color="#75507B">: &quot;yay!&quot;</font>
-//!     <font color="#AAAAAA"><i>at</i></font> examples/examples/fmt/yak_shave.rs:14<font color="#AAAAAA"><i> on</i></font> main
-//!     <font color="#AAAAAA"><i>in</i></font> fmt_pretty::yak_shave::<b>shave</b> <font color="#AAAAAA"><i>with</i></font> <b>yak</b>: 1
-//!     <font color="#AAAAAA"><i>in</i></font> fmt_pretty::yak_shave::<b>shaving_yaks</b> <font color="#AAAAAA"><i>with</i></font> <b>yaks</b>: 3
-//!
-//!   Oct 24 12:57:29.387 <font color="#75507B"><b>fmt_pretty::yak_shave</b></font><font color="#75507B">: yak shaved successfully</font>
-//!     <font color="#AAAAAA"><i>at</i></font> examples/examples/fmt/yak_shave.rs:22<font color="#AAAAAA"><i> on</i></font> main
-//!     <font color="#AAAAAA"><i>in</i></font> fmt_pretty::yak_shave::<b>shave</b> <font color="#AAAAAA"><i>with</i></font> <b>yak</b>: 1
-//!     <font color="#AAAAAA"><i>in</i></font> fmt_pretty::yak_shave::<b>shaving_yaks</b> <font color="#AAAAAA"><i>with</i></font> <b>yaks</b>: 3
-//!
-//!   Oct 24 12:57:29.387 <font color="#3465A4"><b>yak_events</b></font><font color="#3465A4">: </font><font color="#3465A4"><b>yak</b></font><font color="#3465A4">: 1, </font><font color="#3465A4"><b>shaved</b></font><font color="#3465A4">: true</font>
-//!     <font color="#AAAAAA"><i>at</i></font> examples/examples/fmt/yak_shave.rs:43<font color="#AAAAAA"><i> on</i></font> main
-//!     <font color="#AAAAAA"><i>in</i></font> fmt_pretty::yak_shave::<b>shaving_yaks</b> <font color="#AAAAAA"><i>with</i></font> <b>yaks</b>: 3
-//!
-//!   Oct 24 12:57:29.387 <font color="#75507B"><b>fmt_pretty::yak_shave</b></font><font color="#75507B">: </font><font color="#75507B"><b>yaks_shaved</b></font><font color="#75507B">: 1</font>
-//!     <font color="#AAAAAA"><i>at</i></font> examples/examples/fmt/yak_shave.rs:52<font color="#AAAAAA"><i> on</i></font> main
-//!     <font color="#AAAAAA"><i>in</i></font> fmt_pretty::yak_shave::<b>shaving_yaks</b> <font color="#AAAAAA"><i>with</i></font> <b>yaks</b>: 3
-//!
-//!   Oct 24 12:57:29.387 <font color="#75507B"><b>fmt_pretty::yak_shave</b></font><font color="#75507B">: hello! I&apos;m gonna shave a yak, </font><font color="#75507B"><b>excitement</b></font><font color="#75507B">: &quot;yay!&quot;</font>
-//!     <font color="#AAAAAA"><i>at</i></font> examples/examples/fmt/yak_shave.rs:14<font color="#AAAAAA"><i> on</i></font> main
-//!     <font color="#AAAAAA"><i>in</i></font> fmt_pretty::yak_shave::<b>shave</b> <font color="#AAAAAA"><i>with</i></font> <b>yak</b>: 2
-//!     <font color="#AAAAAA"><i>in</i></font> fmt_pretty::yak_shave::<b>shaving_yaks</b> <font color="#AAAAAA"><i>with</i></font> <b>yaks</b>: 3
-//!
-//!   Oct 24 12:57:29.387 <font color="#75507B"><b>fmt_pretty::yak_shave</b></font><font color="#75507B">: yak shaved successfully</font>
-//!     <font color="#AAAAAA"><i>at</i></font> examples/examples/fmt/yak_shave.rs:22<font color="#AAAAAA"><i> on</i></font> main
-//!     <font color="#AAAAAA"><i>in</i></font> fmt_pretty::yak_shave::<b>shave</b> <font color="#AAAAAA"><i>with</i></font> <b>yak</b>: 2
-//!     <font color="#AAAAAA"><i>in</i></font> fmt_pretty::yak_shave::<b>shaving_yaks</b> <font color="#AAAAAA"><i>with</i></font> <b>yaks</b>: 3
-//!
-//!   Oct 24 12:57:29.387 <font color="#3465A4"><b>yak_events</b></font><font color="#3465A4">: </font><font color="#3465A4"><b>yak</b></font><font color="#3465A4">: 2, </font><font color="#3465A4"><b>shaved</b></font><font color="#3465A4">: true</font>
-//!     <font color="#AAAAAA"><i>at</i></font> examples/examples/fmt/yak_shave.rs:43<font color="#AAAAAA"><i> on</i></font> main
-//!     <font color="#AAAAAA"><i>in</i></font> fmt_pretty::yak_shave::<b>shaving_yaks</b> <font color="#AAAAAA"><i>with</i></font> <b>yaks</b>: 3
-//!
-//!   Oct 24 12:57:29.387 <font color="#75507B"><b>fmt_pretty::yak_shave</b></font><font color="#75507B">: </font><font color="#75507B"><b>yaks_shaved</b></font><font color="#75507B">: 2</font>
-//!     <font color="#AAAAAA"><i>at</i></font> examples/examples/fmt/yak_shave.rs:52<font color="#AAAAAA"><i> on</i></font> main
-//!     <font color="#AAAAAA"><i>in</i></font> fmt_pretty::yak_shave::<b>shaving_yaks</b> <font color="#AAAAAA"><i>with</i></font> <b>yaks</b>: 3
-//!
-//!   Oct 24 12:57:29.387 <font color="#75507B"><b>fmt_pretty::yak_shave</b></font><font color="#75507B">: hello! I&apos;m gonna shave a yak, </font><font color="#75507B"><b>excitement</b></font><font color="#75507B">: &quot;yay!&quot;</font>
-//!     <font color="#AAAAAA"><i>at</i></font> examples/examples/fmt/yak_shave.rs:14<font color="#AAAAAA"><i> on</i></font> main
-//!     <font color="#AAAAAA"><i>in</i></font> fmt_pretty::yak_shave::<b>shave</b> <font color="#AAAAAA"><i>with</i></font> <b>yak</b>: 3
-//!     <font color="#AAAAAA"><i>in</i></font> fmt_pretty::yak_shave::<b>shaving_yaks</b> <font color="#AAAAAA"><i>with</i></font> <b>yaks</b>: 3
-//!
-//!   Oct 24 12:57:29.387 <font color="#C4A000"><b>fmt_pretty::yak_shave</b></font><font color="#C4A000">: could not locate yak</font>
-//!     <font color="#AAAAAA"><i>at</i></font> examples/examples/fmt/yak_shave.rs:16<font color="#AAAAAA"><i> on</i></font> main
-//!     <font color="#AAAAAA"><i>in</i></font> fmt_pretty::yak_shave::<b>shave</b> <font color="#AAAAAA"><i>with</i></font> <b>yak</b>: 3
-//!     <font color="#AAAAAA"><i>in</i></font> fmt_pretty::yak_shave::<b>shaving_yaks</b> <font color="#AAAAAA"><i>with</i></font> <b>yaks</b>: 3
-//!
-//!   Oct 24 12:57:29.387 <font color="#3465A4"><b>yak_events</b></font><font color="#3465A4">: </font><font color="#3465A4"><b>yak</b></font><font color="#3465A4">: 3, </font><font color="#3465A4"><b>shaved</b></font><font color="#3465A4">: false</font>
-//!     <font color="#AAAAAA"><i>at</i></font> examples/examples/fmt/yak_shave.rs:43<font color="#AAAAAA"><i> on</i></font> main
-//!     <font color="#AAAAAA"><i>in</i></font> fmt_pretty::yak_shave::<b>shaving_yaks</b> <font color="#AAAAAA"><i>with</i></font> <b>yaks</b>: 3
-//!
-//!   Oct 24 12:57:29.387 <font color="#CC0000"><b>fmt_pretty::yak_shave</b></font><font color="#CC0000">: failed to shave yak, </font><font color="#CC0000"><b>yak</b></font><font color="#CC0000">: 3, </font><font color="#CC0000"><b>error</b></font><font color="#CC0000">: missing yak</font>
-//!     <font color="#AAAAAA"><i>at</i></font> examples/examples/fmt/yak_shave.rs:48<font color="#AAAAAA"><i> on</i></font> main
-//!     <font color="#AAAAAA"><i>in</i></font> fmt_pretty::yak_shave::<b>shaving_yaks</b> <font color="#AAAAAA"><i>with</i></font> <b>yaks</b>: 3
-//!
-//!   Oct 24 12:57:29.387 <font color="#75507B"><b>fmt_pretty::yak_shave</b></font><font color="#75507B">: </font><font color="#75507B"><b>yaks_shaved</b></font><font color="#75507B">: 2</font>
-//!     <font color="#AAAAAA"><i>at</i></font> examples/examples/fmt/yak_shave.rs:52<font color="#AAAAAA"><i> on</i></font> main
-//!     <font color="#AAAAAA"><i>in</i></font> fmt_pretty::yak_shave::<b>shaving_yaks</b> <font color="#AAAAAA"><i>with</i></font> <b>yaks</b>: 3
-//!
-//!   Oct 24 12:57:29.387 <font color="#4E9A06"><b>fmt_pretty</b></font><font color="#4E9A06">: yak shaving completed, </font><font color="#4E9A06"><b>all_yaks_shaved</b></font><font color="#4E9A06">: false</font>
-//!     <font color="#AAAAAA"><i>at</i></font> examples/examples/fmt-pretty.rs:19<font color="#AAAAAA"><i> on</i></font> main
-//!   </pre>
+//!   readability and visual appeal. See [here](format::Pretty#example-output)
+//!   for sample output.
 //!
 //! * [`format::Json`]: Outputs newline-delimited JSON logs. This is intended
 //!   for production use with systems where structured logs are consumed as JSON
-//!   by analysis and viewing tools. The JSON output, as seen below, is *not*
-//!   optimized for human readability.
-//!
-//!   For example:
-//!   <pre><font color="#4E9A06"><b>    Finished</b></font> dev [unoptimized + debuginfo] target(s) in 1.58s
-//!   <font color="#4E9A06"><b>     Running</b></font> `target/debug/examples/fmt-json`
-//!   {&quot;timestamp&quot;:&quot;Oct 24 13:00:00.873&quot;,&quot;level&quot;:&quot;INFO&quot;,&quot;fields&quot;:{&quot;message&quot;:&quot;preparing to shave yaks&quot;,&quot;number_of_yaks&quot;:3},&quot;target&quot;:&quot;fmt_json&quot;}
-//!   {&quot;timestamp&quot;:&quot;Oct 24 13:00:00.874&quot;,&quot;level&quot;:&quot;INFO&quot;,&quot;fields&quot;:{&quot;message&quot;:&quot;shaving yaks&quot;},&quot;target&quot;:&quot;fmt_json::yak_shave&quot;,&quot;spans&quot;:[{&quot;yaks&quot;:3,&quot;name&quot;:&quot;shaving_yaks&quot;}]}
-//!   {&quot;timestamp&quot;:&quot;Oct 24 13:00:00.874&quot;,&quot;level&quot;:&quot;TRACE&quot;,&quot;fields&quot;:{&quot;message&quot;:&quot;hello! I&apos;m gonna shave a yak&quot;,&quot;excitement&quot;:&quot;yay!&quot;},&quot;target&quot;:&quot;fmt_json::yak_shave&quot;,&quot;spans&quot;:[{&quot;yaks&quot;:3,&quot;name&quot;:&quot;shaving_yaks&quot;},{&quot;yak&quot;:&quot;1&quot;,&quot;name&quot;:&quot;shave&quot;}]}
-//!   {&quot;timestamp&quot;:&quot;Oct 24 13:00:00.874&quot;,&quot;level&quot;:&quot;TRACE&quot;,&quot;fields&quot;:{&quot;message&quot;:&quot;yak shaved successfully&quot;},&quot;target&quot;:&quot;fmt_json::yak_shave&quot;,&quot;spans&quot;:[{&quot;yaks&quot;:3,&quot;name&quot;:&quot;shaving_yaks&quot;},{&quot;yak&quot;:&quot;1&quot;,&quot;name&quot;:&quot;shave&quot;}]}
-//!   {&quot;timestamp&quot;:&quot;Oct 24 13:00:00.874&quot;,&quot;level&quot;:&quot;DEBUG&quot;,&quot;fields&quot;:{&quot;yak&quot;:1,&quot;shaved&quot;:true},&quot;target&quot;:&quot;yak_events&quot;,&quot;spans&quot;:[{&quot;yaks&quot;:3,&quot;name&quot;:&quot;shaving_yaks&quot;}]}
-//!   {&quot;timestamp&quot;:&quot;Oct 24 13:00:00.874&quot;,&quot;level&quot;:&quot;TRACE&quot;,&quot;fields&quot;:{&quot;yaks_shaved&quot;:1},&quot;target&quot;:&quot;fmt_json::yak_shave&quot;,&quot;spans&quot;:[{&quot;yaks&quot;:3,&quot;name&quot;:&quot;shaving_yaks&quot;}]}
-//!   {&quot;timestamp&quot;:&quot;Oct 24 13:00:00.874&quot;,&quot;level&quot;:&quot;TRACE&quot;,&quot;fields&quot;:{&quot;message&quot;:&quot;hello! I&apos;m gonna shave a yak&quot;,&quot;excitement&quot;:&quot;yay!&quot;},&quot;target&quot;:&quot;fmt_json::yak_shave&quot;,&quot;spans&quot;:[{&quot;yaks&quot;:3,&quot;name&quot;:&quot;shaving_yaks&quot;},{&quot;yak&quot;:&quot;2&quot;,&quot;name&quot;:&quot;shave&quot;}]}
-//!   {&quot;timestamp&quot;:&quot;Oct 24 13:00:00.874&quot;,&quot;level&quot;:&quot;TRACE&quot;,&quot;fields&quot;:{&quot;message&quot;:&quot;yak shaved successfully&quot;},&quot;target&quot;:&quot;fmt_json::yak_shave&quot;,&quot;spans&quot;:[{&quot;yaks&quot;:3,&quot;name&quot;:&quot;shaving_yaks&quot;},{&quot;yak&quot;:&quot;2&quot;,&quot;name&quot;:&quot;shave&quot;}]}
-//!   {&quot;timestamp&quot;:&quot;Oct 24 13:00:00.874&quot;,&quot;level&quot;:&quot;DEBUG&quot;,&quot;fields&quot;:{&quot;yak&quot;:2,&quot;shaved&quot;:true},&quot;target&quot;:&quot;yak_events&quot;,&quot;spans&quot;:[{&quot;yaks&quot;:3,&quot;name&quot;:&quot;shaving_yaks&quot;}]}
-//!   {&quot;timestamp&quot;:&quot;Oct 24 13:00:00.874&quot;,&quot;level&quot;:&quot;TRACE&quot;,&quot;fields&quot;:{&quot;yaks_shaved&quot;:2},&quot;target&quot;:&quot;fmt_json::yak_shave&quot;,&quot;spans&quot;:[{&quot;yaks&quot;:3,&quot;name&quot;:&quot;shaving_yaks&quot;}]}
-//!   {&quot;timestamp&quot;:&quot;Oct 24 13:00:00.874&quot;,&quot;level&quot;:&quot;TRACE&quot;,&quot;fields&quot;:{&quot;message&quot;:&quot;hello! I&apos;m gonna shave a yak&quot;,&quot;excitement&quot;:&quot;yay!&quot;},&quot;target&quot;:&quot;fmt_json::yak_shave&quot;,&quot;spans&quot;:[{&quot;yaks&quot;:3,&quot;name&quot;:&quot;shaving_yaks&quot;},{&quot;yak&quot;:&quot;3&quot;,&quot;name&quot;:&quot;shave&quot;}]}
-//!   {&quot;timestamp&quot;:&quot;Oct 24 13:00:00.875&quot;,&quot;level&quot;:&quot;WARN&quot;,&quot;fields&quot;:{&quot;message&quot;:&quot;could not locate yak&quot;},&quot;target&quot;:&quot;fmt_json::yak_shave&quot;,&quot;spans&quot;:[{&quot;yaks&quot;:3,&quot;name&quot;:&quot;shaving_yaks&quot;},{&quot;yak&quot;:&quot;3&quot;,&quot;name&quot;:&quot;shave&quot;}]}
-//!   {&quot;timestamp&quot;:&quot;Oct 24 13:00:00.875&quot;,&quot;level&quot;:&quot;DEBUG&quot;,&quot;fields&quot;:{&quot;yak&quot;:3,&quot;shaved&quot;:false},&quot;target&quot;:&quot;yak_events&quot;,&quot;spans&quot;:[{&quot;yaks&quot;:3,&quot;name&quot;:&quot;shaving_yaks&quot;}]}
-//!   {&quot;timestamp&quot;:&quot;Oct 24 13:00:00.875&quot;,&quot;level&quot;:&quot;ERROR&quot;,&quot;fields&quot;:{&quot;message&quot;:&quot;failed to shave yak&quot;,&quot;yak&quot;:3,&quot;error&quot;:&quot;missing yak&quot;},&quot;target&quot;:&quot;fmt_json::yak_shave&quot;,&quot;spans&quot;:[{&quot;yaks&quot;:3,&quot;name&quot;:&quot;shaving_yaks&quot;}]}
-//!   {&quot;timestamp&quot;:&quot;Oct 24 13:00:00.875&quot;,&quot;level&quot;:&quot;TRACE&quot;,&quot;fields&quot;:{&quot;yaks_shaved&quot;:2},&quot;target&quot;:&quot;fmt_json::yak_shave&quot;,&quot;spans&quot;:[{&quot;yaks&quot;:3,&quot;name&quot;:&quot;shaving_yaks&quot;}]}
-//!   {&quot;timestamp&quot;:&quot;Oct 24 13:00:00.875&quot;,&quot;level&quot;:&quot;INFO&quot;,&quot;fields&quot;:{&quot;message&quot;:&quot;yak shaving completed&quot;,&quot;all_yaks_shaved&quot;:false},&quot;target&quot;:&quot;fmt_json&quot;}
-//!   </pre>
+//!   by analysis and viewing tools. The JSON output is not optimized for human
+//!   readability. See [here](format::Json#example-output) for sample output.
 //!
 //! ### Customizing Formatters
 //!
@@ -221,7 +116,7 @@
 //!    .with_thread_names(true) // include the name of the current thread
 //!    .compact(); // use the `Compact` formatting style.
 //!
-//! // Create a `fmt` collector that uses our custom event format, and set it
+//! // Create a `fmt` subscriber that uses our custom event format, and set it
 //! // as the default.
 //! tracing_subscriber::fmt()
 //!     .event_format(format)
@@ -268,7 +163,7 @@
 //!
 //! ### Composing Layers
 //!
-//! Composing an [`EnvFilter`] `Layer` and a [format `Layer`](../fmt/struct.Layer.html):
+//! Composing an [`EnvFilter`] `Layer` and a [format `Layer`][super::fmt::Layer]:
 //!
 //! ```rust
 //! use tracing_subscriber::{fmt, EnvFilter};
@@ -286,11 +181,10 @@
 //!     .init();
 //! ```
 //!
-//! [`EnvFilter`]: ../filter/struct.EnvFilter.html
+//! [`EnvFilter`]: super::filter::EnvFilter
 //! [`env_logger`]: https://docs.rs/env_logger/
-//! [`filter`]: ../filter/index.html
-//! [`SubscriberBuilder`]: ./struct.SubscriberBuilder.html
-//! [`FmtSubscriber`]: ./struct.Subscriber.html
+//! [`filter`]: super::filter
+//! [`FmtSubscriber`]: Subscriber
 //! [`Subscriber`]:
 //!     https://docs.rs/tracing/latest/tracing/trait.Subscriber.html
 //! [`tracing`]: https://crates.io/crates/tracing
@@ -309,6 +203,7 @@ pub mod writer;
 pub use fmt_layer::{FmtContext, FormattedFields, Layer};
 
 use crate::layer::Layer as _;
+use crate::util::SubscriberInitExt;
 use crate::{
     filter::LevelFilter,
     layer,
@@ -348,6 +243,7 @@ pub type Formatter<
 /// Configures and constructs `Subscriber`s.
 #[cfg_attr(docsrs, doc(cfg(all(feature = "fmt", feature = "std"))))]
 #[derive(Debug)]
+#[must_use]
 pub struct SubscriberBuilder<
     N = format::DefaultFields,
     E = format::Format<format::Full>,
@@ -417,7 +313,7 @@ pub struct SubscriberBuilder<
 /// ```
 ///
 /// [formatting subscriber]: Subscriber
-/// [`SubscriberBuilder::default()`]: SubscriberBuilder::default()
+/// [`SubscriberBuilder::default()`]: SubscriberBuilder::default
 /// [`init`]: SubscriberBuilder::init()
 /// [`try_init`]: SubscriberBuilder::try_init()
 /// [`finish`]: SubscriberBuilder::finish()
@@ -429,10 +325,11 @@ pub fn fmt() -> SubscriberBuilder {
 /// Returns a new [formatting layer] that can be [composed] with other layers to
 /// construct a [`Subscriber`].
 ///
-/// This is a shorthand for the equivalent [`Layer::default`] function.
+/// This is a shorthand for the equivalent [`Layer::default()`] function.
 ///
 /// [formatting layer]: Layer
 /// [composed]: crate::layer
+/// [`Layer::default()`]: Layer::default
 #[cfg_attr(docsrs, doc(cfg(all(feature = "fmt", feature = "std"))))]
 pub fn layer<S>() -> Layer<S> {
     Layer::default()
@@ -444,8 +341,8 @@ impl Subscriber {
     ///
     /// This can be overridden with the [`SubscriberBuilder::with_max_level`] method.
     ///
-    /// [verbosity level]: https://docs.rs/tracing-core/0.1.5/tracing_core/struct.Level.html
-    /// [`SubscriberBuilder::with_max_level`]: struct.SubscriberBuilder.html#method.with_max_level
+    /// [verbosity level]: tracing_core::Level
+    /// [`SubscriberBuilder::with_max_level`]: SubscriberBuilder::with_max_level
     pub const DEFAULT_MAX_LEVEL: LevelFilter = LevelFilter::INFO;
 
     /// Returns a new `SubscriberBuilder` for configuring a format subscriber.
@@ -502,6 +399,11 @@ where
     }
 
     #[inline]
+    fn event_enabled(&self, event: &Event<'_>) -> bool {
+        self.inner.event_enabled(event)
+    }
+
+    #[inline]
     fn event(&self, event: &Event<'_>) {
         self.inner.event(event);
     }
@@ -565,6 +467,7 @@ impl Default for SubscriberBuilder {
             filter: Subscriber::DEFAULT_MAX_LEVEL,
             inner: Default::default(),
         }
+        .log_internal_errors(true)
     }
 }
 
@@ -701,7 +604,7 @@ where
     /// `Layer`s added to this subscriber.
     ///
     /// [lifecycle]: https://docs.rs/tracing/latest/tracing/span/index.html#the-span-lifecycle
-    /// [time]: #method.without_time
+    /// [time]: SubscriberBuilder::without_time()
     pub fn with_span_events(self, kind: format::FmtSpan) -> Self {
         SubscriberBuilder {
             inner: self.inner.with_span_events(kind),
@@ -719,6 +622,27 @@ where
         }
     }
 
+    /// Sets whether to write errors from [`FormatEvent`] to the writer.
+    /// Defaults to true.
+    ///
+    /// By default, `fmt::Layer` will write any `FormatEvent`-internal errors to
+    /// the writer. These errors are unlikely and will only occur if there is a
+    /// bug in the `FormatEvent` implementation or its dependencies.
+    ///
+    /// If writing to the writer fails, the error message is printed to stderr
+    /// as a fallback.
+    ///
+    /// [`FormatEvent`]: crate::fmt::FormatEvent
+    pub fn log_internal_errors(
+        self,
+        log_internal_errors: bool,
+    ) -> SubscriberBuilder<N, format::Format<L, T>, F, W> {
+        SubscriberBuilder {
+            inner: self.inner.log_internal_errors(log_internal_errors),
+            ..self
+        }
+    }
+
     /// Sets whether or not an event's target is displayed.
     pub fn with_target(
         self,
@@ -730,6 +654,34 @@ where
         }
     }
 
+    /// Sets whether or not an event's [source code file path][file] is
+    /// displayed.
+    ///
+    /// [file]: tracing_core::Metadata::file
+    pub fn with_file(
+        self,
+        display_filename: bool,
+    ) -> SubscriberBuilder<N, format::Format<L, T>, F, W> {
+        SubscriberBuilder {
+            inner: self.inner.with_file(display_filename),
+            ..self
+        }
+    }
+
+    /// Sets whether or not an event's [source code line number][line] is
+    /// displayed.
+    ///
+    /// [line]: tracing_core::Metadata::line
+    pub fn with_line_number(
+        self,
+        display_line_number: bool,
+    ) -> SubscriberBuilder<N, format::Format<L, T>, F, W> {
+        SubscriberBuilder {
+            inner: self.inner.with_line_number(display_line_number),
+            ..self
+        }
+    }
+
     /// Sets whether or not an event's level is displayed.
     pub fn with_level(
         self,
@@ -742,9 +694,9 @@ where
     }
 
     /// Sets whether or not the [name] of the current thread is displayed
-    /// when formatting events
+    /// when formatting events.
     ///
-    /// [name]: https://doc.rust-lang.org/stable/std/thread/index.html#naming-threads
+    /// [name]: std::thread#naming-threads
     pub fn with_thread_names(
         self,
         display_thread_names: bool,
@@ -756,9 +708,9 @@ where
     }
 
     /// Sets whether or not the [thread ID] of the current thread is displayed
-    /// when formatting events
+    /// when formatting events.
     ///
-    /// [thread ID]: https://doc.rust-lang.org/stable/std/thread/struct.ThreadId.html
+    /// [thread ID]: std::thread::ThreadId
     pub fn with_thread_ids(
         self,
         display_thread_ids: bool,
@@ -796,7 +748,7 @@ where
 
     /// Sets the subscriber being built to use a JSON formatter.
     ///
-    /// See [`format::Json`](../fmt/format/struct.Json.html)
+    /// See [`format::Json`][super::fmt::format::Json]
     #[cfg(feature = "json")]
     #[cfg_attr(docsrs, doc(cfg(feature = "json")))]
     pub fn json(
@@ -817,7 +769,7 @@ where
 impl<T, F, W> SubscriberBuilder<format::JsonFields, format::Format<format::Json, T>, F, W> {
     /// Sets the json subscriber being built to flatten event metadata.
     ///
-    /// See [`format::Json`](../fmt/format/struct.Json.html)
+    /// See [`format::Json`][super::fmt::format::Json]
     pub fn flatten_event(
         self,
         flatten_event: bool,
@@ -831,7 +783,7 @@ impl<T, F, W> SubscriberBuilder<format::JsonFields, format::Format<format::Json,
     /// Sets whether or not the JSON subscriber being built will include the current span
     /// in formatted events.
     ///
-    /// See [`format::Json`](../fmt/format/struct.Json.html)
+    /// See [`format::Json`][super::fmt::format::Json]
     pub fn with_current_span(
         self,
         display_current_span: bool,
@@ -845,7 +797,7 @@ impl<T, F, W> SubscriberBuilder<format::JsonFields, format::Format<format::Json,
     /// Sets whether or not the JSON subscriber being built will include a list (from
     /// root to leaf) of all currently entered spans in formatted events.
     ///
-    /// See [`format::Json`](../fmt/format/struct.Json.html)
+    /// See [`format::Json`][super::fmt::format::Json]
     pub fn with_span_list(
         self,
         display_span_list: bool,
@@ -891,7 +843,7 @@ where
 }
 
 impl<N, E, F, W> SubscriberBuilder<N, E, F, W> {
-    /// Sets the Visitor that the subscriber being built will use to record
+    /// Sets the field formatter that the subscriber being built will use to record
     /// fields.
     ///
     /// For example:
@@ -967,8 +919,8 @@ impl<N, E, F, W> SubscriberBuilder<N, E, F, W> {
     ///     .try_init()?;
     /// # Ok(())}
     /// ```
-    /// [`EnvFilter`]: ../filter/struct.EnvFilter.html
-    /// [`with_max_level`]: #method.with_max_level
+    /// [`EnvFilter`]: super::filter::EnvFilter
+    /// [`with_max_level`]: SubscriberBuilder::with_max_level()
     #[cfg(feature = "env-filter")]
     #[cfg_attr(docsrs, doc(cfg(feature = "env-filter")))]
     pub fn with_env_filter(
@@ -989,7 +941,7 @@ impl<N, E, F, W> SubscriberBuilder<N, E, F, W> {
     /// subscriber.
     ///
     /// If the max level has already been set, or a [`EnvFilter`] was added by
-    /// [`with_filter`], this replaces that configuration with the new
+    /// [`with_env_filter`], this replaces that configuration with the new
     /// maximum level.
     ///
     /// # Examples
@@ -1011,9 +963,9 @@ impl<N, E, F, W> SubscriberBuilder<N, E, F, W> {
     ///     .with_max_level(LevelFilter::OFF)
     ///     .finish();
     /// ```
-    /// [verbosity level]: https://docs.rs/tracing-core/0.1.5/tracing_core/struct.Level.html
-    /// [`EnvFilter`]: ../filter/struct.EnvFilter.html
-    /// [`with_filter`]: #method.with_filter
+    /// [verbosity level]: tracing_core::Level
+    /// [`EnvFilter`]: struct@crate::filter::EnvFilter
+    /// [`with_env_filter`]: fn@Self::with_env_filter
     pub fn with_max_level(
         self,
         filter: impl Into<LevelFilter>,
@@ -1025,8 +977,26 @@ impl<N, E, F, W> SubscriberBuilder<N, E, F, W> {
         }
     }
 
-    /// Sets the function that the subscriber being built should use to format
-    /// events that occur.
+    /// Sets the [event formatter][`FormatEvent`] that the subscriber being built
+    /// will use to format events that occur.
+    ///
+    /// The event formatter may be any type implementing the [`FormatEvent`]
+    /// trait, which is implemented for all functions taking a [`FmtContext`], a
+    /// [`Writer`], and an [`Event`].
+    ///
+    /// # Examples
+    ///
+    /// Setting a type implementing [`FormatEvent`] as the formatter:
+    ///
+    /// ```rust
+    /// use tracing_subscriber::fmt::format;
+    ///
+    /// let subscriber = tracing_subscriber::fmt()
+    ///     .event_format(format().compact())
+    ///     .finish();
+    /// ```
+    ///
+    /// [`Writer`]: struct@self::format::Writer
     pub fn event_format<E2>(self, fmt_event: E2) -> SubscriberBuilder<N, E2, F, W>
     where
         E2: FormatEvent<Registry, N> + 'static,
@@ -1053,8 +1023,6 @@ impl<N, E, F, W> SubscriberBuilder<N, E, F, W> {
     ///     .with_writer(io::stderr)
     ///     .init();
     /// ```
-    ///
-    /// [`MakeWriter`]: trait.MakeWriter.html
     pub fn with_writer<W2>(self, make_writer: W2) -> SubscriberBuilder<N, E, F, W2>
     where
         W2: for<'writer> MakeWriter<'writer> + 'static,
@@ -1088,13 +1056,89 @@ impl<N, E, F, W> SubscriberBuilder<N, E, F, W> {
     ///
     /// [capturing]:
     /// https://doc.rust-lang.org/book/ch11-02-running-tests.html#showing-function-output
-    /// [`TestWriter`]: writer/struct.TestWriter.html
+    /// [`TestWriter`]: writer::TestWriter
     pub fn with_test_writer(self) -> SubscriberBuilder<N, E, F, TestWriter> {
         SubscriberBuilder {
             filter: self.filter,
             inner: self.inner.with_writer(TestWriter::default()),
         }
     }
+
+    /// Updates the event formatter by applying a function to the existing event formatter.
+    ///
+    /// This sets the event formatter that the subscriber being built will use to record fields.
+    ///
+    /// # Examples
+    ///
+    /// Updating an event formatter:
+    ///
+    /// ```rust
+    /// let subscriber = tracing_subscriber::fmt()
+    ///     .map_event_format(|e| e.compact())
+    ///     .finish();
+    /// ```
+    pub fn map_event_format<E2>(self, f: impl FnOnce(E) -> E2) -> SubscriberBuilder<N, E2, F, W>
+    where
+        E2: FormatEvent<Registry, N> + 'static,
+        N: for<'writer> FormatFields<'writer> + 'static,
+        W: for<'writer> MakeWriter<'writer> + 'static,
+    {
+        SubscriberBuilder {
+            filter: self.filter,
+            inner: self.inner.map_event_format(f),
+        }
+    }
+
+    /// Updates the field formatter by applying a function to the existing field formatter.
+    ///
+    /// This sets the field formatter that the subscriber being built will use to record fields.
+    ///
+    /// # Examples
+    ///
+    /// Updating a field formatter:
+    ///
+    /// ```rust
+    /// use tracing_subscriber::field::MakeExt;
+    /// let subscriber = tracing_subscriber::fmt()
+    ///     .map_fmt_fields(|f| f.debug_alt())
+    ///     .finish();
+    /// ```
+    pub fn map_fmt_fields<N2>(self, f: impl FnOnce(N) -> N2) -> SubscriberBuilder<N2, E, F, W>
+    where
+        N2: for<'writer> FormatFields<'writer> + 'static,
+    {
+        SubscriberBuilder {
+            filter: self.filter,
+            inner: self.inner.map_fmt_fields(f),
+        }
+    }
+
+    /// Updates the [`MakeWriter`] by applying a function to the existing [`MakeWriter`].
+    ///
+    /// This sets the [`MakeWriter`] that the subscriber being built will use to write events.
+    ///
+    /// # Examples
+    ///
+    /// Redirect output to stderr if level is <= WARN:
+    ///
+    /// ```rust
+    /// use tracing::Level;
+    /// use tracing_subscriber::fmt::{self, writer::MakeWriterExt};
+    ///
+    /// let stderr = std::io::stderr.with_max_level(Level::WARN);
+    /// let layer = tracing_subscriber::fmt()
+    ///     .map_writer(move |w| stderr.or_else(w))
+    ///     .finish();
+    /// ```
+    pub fn map_writer<W2>(self, f: impl FnOnce(W) -> W2) -> SubscriberBuilder<N, E, F, W2>
+    where
+        W2: for<'writer> MakeWriter<'writer> + 'static,
+    {
+        SubscriberBuilder {
+            filter: self.filter,
+            inner: self.inner.map_writer(f),
+        }
+    }
 }
 
 /// Install a global tracing subscriber that listens for events and
@@ -1121,35 +1165,69 @@ impl<N, E, F, W> SubscriberBuilder<N, E, F, W> {
 ///
 /// [`LogTracer`]:
 ///     https://docs.rs/tracing-log/0.1.0/tracing_log/struct.LogTracer.html
-/// [`RUST_LOG` environment variable]:
-///     ../filter/struct.EnvFilter.html#associatedconstant.DEFAULT_ENV
+/// [`RUST_LOG` environment variable]: crate::filter::EnvFilter::DEFAULT_ENV
 pub fn try_init() -> Result<(), Box<dyn Error + Send + Sync + 'static>> {
     let builder = Subscriber::builder();
 
     #[cfg(feature = "env-filter")]
     let builder = builder.with_env_filter(crate::EnvFilter::from_default_env());
 
-    builder.try_init()
+    // If `env-filter` is disabled, remove the default max level filter from the
+    // subscriber; it will be added to the `Targets` filter instead if no filter
+    // is set in `RUST_LOG`.
+    // Replacing the default `LevelFilter` with an `EnvFilter` would imply this,
+    // but we can't replace the builder's filter with a `Targets` filter yet.
+    #[cfg(not(feature = "env-filter"))]
+    let builder = builder.with_max_level(LevelFilter::TRACE);
+
+    let subscriber = builder.finish();
+    #[cfg(not(feature = "env-filter"))]
+    let subscriber = {
+        use crate::{filter::Targets, layer::SubscriberExt};
+        use std::{env, str::FromStr};
+        let targets = match env::var("RUST_LOG") {
+            Ok(var) => Targets::from_str(&var)
+                .map_err(|e| {
+                    eprintln!("Ignoring `RUST_LOG={:?}`: {}", var, e);
+                })
+                .unwrap_or_default(),
+            Err(env::VarError::NotPresent) => {
+                Targets::new().with_default(Subscriber::DEFAULT_MAX_LEVEL)
+            }
+            Err(e) => {
+                eprintln!("Ignoring `RUST_LOG`: {}", e);
+                Targets::new().with_default(Subscriber::DEFAULT_MAX_LEVEL)
+            }
+        };
+        subscriber.with(targets)
+    };
+
+    subscriber.try_init().map_err(Into::into)
 }
 
 /// Install a global tracing subscriber that listens for events and
 /// filters based on the value of the [`RUST_LOG` environment variable].
 ///
+/// The configuration of the subscriber initialized by this function
+/// depends on what [feature flags](crate#feature-flags) are enabled.
+///
 /// If the `tracing-log` feature is enabled, this will also install
 /// the LogTracer to convert `Log` records into `tracing` `Event`s.
 ///
-/// This is shorthand for
+/// If the `env-filter` feature is enabled, this is shorthand for
 ///
 /// ```rust
-/// tracing_subscriber::fmt().init()
+/// # use tracing_subscriber::EnvFilter;
+/// tracing_subscriber::fmt()
+///     .with_env_filter(EnvFilter::from_default_env())
+///     .init();
 /// ```
 ///
 /// # Panics
 /// Panics if the initialization was unsuccessful, likely because a
 /// global subscriber was already installed by another call to `try_init`.
 ///
-/// [`RUST_LOG` environment variable]:
-///     ../filter/struct.EnvFilter.html#associatedconstant.DEFAULT_ENV
+/// [`RUST_LOG` environment variable]: crate::filter::EnvFilter::DEFAULT_ENV
 pub fn init() {
     try_init().expect("Unable to install global subscriber")
 }
diff --git a/vendor/tracing-subscriber-0.3.3/src/fmt/time/datetime.rs b/vendor/tracing-subscriber/src/fmt/time/datetime.rs
index 531331687..531331687 100644
--- a/vendor/tracing-subscriber-0.3.3/src/fmt/time/datetime.rs
+++ b/vendor/tracing-subscriber/src/fmt/time/datetime.rs
diff --git a/vendor/tracing-subscriber-0.3.3/src/fmt/time/mod.rs b/vendor/tracing-subscriber/src/fmt/time/mod.rs
index 621df16e4..e5b7c83b0 100644
--- a/vendor/tracing-subscriber-0.3.3/src/fmt/time/mod.rs
+++ b/vendor/tracing-subscriber/src/fmt/time/mod.rs
@@ -12,9 +12,13 @@ mod time_crate;
 pub use time_crate::UtcTime;
 
 #[cfg(feature = "local-time")]
-#[cfg_attr(docsrs, doc(cfg(feature = "local-time")))]
+#[cfg_attr(docsrs, doc(cfg(unsound_local_offset, feature = "local-time")))]
 pub use time_crate::LocalTime;
 
+#[cfg(feature = "time")]
+#[cfg_attr(docsrs, doc(cfg(feature = "time")))]
+pub use time_crate::OffsetTime;
+
 /// A type that can measure and format the current time.
 ///
 /// This trait is used by `Format` to include a timestamp with each `Event` when it is logged.
@@ -26,7 +30,7 @@ pub use time_crate::LocalTime;
 ///
 /// The full list of provided implementations can be found in [`time`].
 ///
-/// [`time`]: ./index.html
+/// [`time`]: self
 pub trait FormatTime {
     /// Measure and write out the current time.
     ///
diff --git a/vendor/tracing-subscriber-0.3.3/src/fmt/writer.rs b/vendor/tracing-subscriber/src/fmt/writer.rs
index 0974891f7..3fe945566 100644
--- a/vendor/tracing-subscriber-0.3.3/src/fmt/writer.rs
+++ b/vendor/tracing-subscriber/src/fmt/writer.rs
@@ -1,6 +1,6 @@
 //! Abstractions for creating [`io::Write`] instances.
 //!
-//! [`io::Write`]: https://doc.rust-lang.org/std/io/trait.Write.html
+//! [`io::Write`]: std::io::Write
 use std::{
     fmt,
     io::{self, Write},
@@ -96,8 +96,8 @@ use tracing_core::Metadata;
 pub trait MakeWriter<'a> {
     /// The concrete [`io::Write`] implementation returned by [`make_writer`].
     ///
-    /// [`io::Write`]: https://doc.rust-lang.org/std/io/trait.Write.html
-    /// [`make_writer`]: #tymethod.make_writer
+    /// [`io::Write`]: std::io::Write
+    /// [`make_writer`]: MakeWriter::make_writer
     type Writer: io::Write;
 
     /// Returns an instance of [`Writer`].
@@ -109,7 +109,7 @@ pub trait MakeWriter<'a> {
     /// creating a [`io::Write`] instance is expensive, be sure to cache it when implementing
     /// [`MakeWriter`] to improve performance.
     ///
-    /// [`Writer`]: #associatedtype.Writer
+    /// [`Writer`]: MakeWriter::Writer
     /// [`fmt::Layer`]: crate::fmt::Layer
     /// [`fmt::Subscriber`]: crate::fmt::Subscriber
     /// [`io::Write`]: std::io::Write
@@ -501,13 +501,13 @@ pub trait MakeWriterExt<'a>: MakeWriter<'a> {
 /// Writing to [`io::stdout`] and [`io::stderr`] produces the same results as using
 /// [`libtest`'s `--nocapture` option][nocapture] which may make the results look unreadable.
 ///
-/// [`fmt::Subscriber`]: ../struct.Subscriber.html
-/// [`fmt::Layer`]: ../struct.Layer.html
+/// [`fmt::Subscriber`]: super::Subscriber
+/// [`fmt::Layer`]: super::Layer
 /// [capturing]: https://doc.rust-lang.org/book/ch11-02-running-tests.html#showing-function-output
 /// [nocapture]: https://doc.rust-lang.org/cargo/commands/cargo-test.html
-/// [`io::stdout`]: https://doc.rust-lang.org/std/io/fn.stdout.html
-/// [`io::stderr`]: https://doc.rust-lang.org/std/io/fn.stderr.html
-/// [`print!`]: https://doc.rust-lang.org/std/macro.print.html
+/// [`io::stdout`]: std::io::stdout
+/// [`io::stderr`]: std::io::stderr
+/// [`print!`]: std::print!
 #[derive(Default, Debug)]
 pub struct TestWriter {
     _p: (),
@@ -646,10 +646,9 @@ pub struct Tee<A, B> {
 /// requires the `Writer` type to implement [`io::Write`], it's necessary to add
 /// a newtype that forwards the trait implementation.
 ///
-/// [`io::Write`]: https://doc.rust-lang.org/std/io/trait.Write.html
-/// [`MutexGuard`]: https://doc.rust-lang.org/std/sync/struct.MutexGuard.html
-/// [`Mutex`]: https://doc.rust-lang.org/std/sync/struct.Mutex.html
-/// [`MakeWriter`]: trait.MakeWriter.html
+/// [`io::Write`]: std::io::Write
+/// [`MutexGuard`]: std::sync::MutexGuard
+/// [`Mutex`]: std::sync::Mutex
 #[derive(Debug)]
 pub struct MutexGuardWriter<'a, W>(MutexGuard<'a, W>);
 
@@ -689,7 +688,7 @@ where
 {
     type Writer = &'a W;
     fn make_writer(&'a self) -> Self::Writer {
-        &*self
+        self
     }
 }
 
@@ -734,7 +733,6 @@ impl<'a> MakeWriter<'a> for TestWriter {
 impl BoxMakeWriter {
     /// Constructs a `BoxMakeWriter` wrapping a type implementing [`MakeWriter`].
     ///
-    /// [`MakeWriter`]: trait.MakeWriter.html
     pub fn new<M>(make_writer: M) -> Self
     where
         M: for<'a> MakeWriter<'a> + Send + Sync + 'static,
@@ -1025,6 +1023,8 @@ impl<A, B> Tee<A, B> {
     /// outputs.
     ///
     /// See the documentation for [`MakeWriterExt::and`] for details.
+    ///
+    /// [writers]: std::io::Write
     pub fn new(a: A, b: B) -> Self {
         Self { a, b }
     }
diff --git a/vendor/tracing-subscriber-0.3.3/src/layer/context.rs b/vendor/tracing-subscriber/src/layer/context.rs
index e11959526..46254994f 100644
--- a/vendor/tracing-subscriber-0.3.3/src/layer/context.rs
+++ b/vendor/tracing-subscriber/src/layer/context.rs
@@ -25,10 +25,10 @@ use crate::{filter::FilterId, registry::Registry};
 /// }
 /// ```
 ///
-/// [`Layer`]: ../layer/trait.Layer.html
-/// [`Subscriber`]: https://docs.rs/tracing-core/latest/tracing_core/trait.Subscriber.html
-/// [stored data]: ../registry/struct.SpanRef.html
-/// [`LookupSpan`]: "../registry/trait.LookupSpan.html
+/// [`Layer`]: super::Layer
+/// [`Subscriber`]: tracing_core::Subscriber
+/// [stored data]: crate::registry::SpanRef
+/// [`LookupSpan`]: crate::registry::LookupSpan
 #[derive(Debug)]
 pub struct Context<'a, S> {
     subscriber: Option<&'a S>,
@@ -99,9 +99,9 @@ where
     ///   check whether the event would be enabled. This allows `Layer`s to
     ///   elide constructing the event if it would not be recorded.
     ///
-    /// [register]: https://docs.rs/tracing-core/latest/tracing_core/subscriber/trait.Subscriber.html#method.register_callsite
-    /// [`enabled`]: https://docs.rs/tracing-core/latest/tracing_core/subscriber/trait.Subscriber.html#method.enabled
-    /// [`Context::enabled`]: #method.enabled
+    /// [register]: tracing_core::subscriber::Subscriber::register_callsite()
+    /// [`enabled`]: tracing_core::subscriber::Subscriber::enabled()
+    /// [`Context::enabled`]: Context::enabled()
     #[inline]
     pub fn event(&self, event: &Event<'_>) {
         if let Some(subscriber) = self.subscriber {
@@ -206,7 +206,7 @@ where
     ///     declaration</a> for details.
     /// </pre>
     ///
-    /// [stored data]: ../registry/struct.SpanRef.html
+    /// [stored data]: crate::registry::SpanRef
     #[inline]
     pub fn span(&self, id: &span::Id) -> Option<registry::SpanRef<'_, S>>
     where
@@ -251,7 +251,7 @@ where
     ///     declaration</a> for details.
     /// </pre>
     ///
-    /// [stored data]: ../registry/struct.SpanRef.html
+    /// [stored data]: crate::registry::SpanRef
     #[inline]
     pub fn lookup_current(&self) -> Option<registry::SpanRef<'_, S>>
     where
@@ -333,7 +333,7 @@ where
     ///     declaration</a> for details.
     /// </pre>
     ///
-    /// [stored data]: ../registry/struct.SpanRef.html
+    /// [stored data]: crate::registry::SpanRef
     pub fn span_scope(&self, id: &span::Id) -> Option<registry::Scope<'_, S>>
     where
         S: for<'lookup> LookupSpan<'lookup>,
@@ -360,7 +360,7 @@ where
     ///     declaration</a> for details.
     /// </pre>
     ///
-    /// [stored data]: ../registry/struct.SpanRef.html
+    /// [stored data]: crate::registry::SpanRef
     pub fn event_scope(&self, event: &Event<'_>) -> Option<registry::Scope<'_, S>>
     where
         S: for<'lookup> LookupSpan<'lookup>,
diff --git a/vendor/tracing-subscriber-0.3.3/src/layer/layered.rs b/vendor/tracing-subscriber/src/layer/layered.rs
index c690764ad..f09c58c97 100644
--- a/vendor/tracing-subscriber-0.3.3/src/layer/layered.rs
+++ b/vendor/tracing-subscriber/src/layer/layered.rs
@@ -1,9 +1,4 @@
-use tracing_core::{
-    metadata::Metadata,
-    span,
-    subscriber::{Interest, Subscriber},
-    Event, LevelFilter,
-};
+use tracing_core::{metadata::Metadata, span, Dispatch, Event, Interest, LevelFilter, Subscriber};
 
 use crate::{
     filter,
@@ -12,13 +7,17 @@ use crate::{
 };
 #[cfg(all(feature = "registry", feature = "std"))]
 use crate::{filter::FilterId, registry::Registry};
-use core::{any::TypeId, cmp, fmt, marker::PhantomData};
+use core::{
+    any::{Any, TypeId},
+    cmp, fmt,
+    marker::PhantomData,
+};
 
 /// A [`Subscriber`] composed of a `Subscriber` wrapped by one or more
 /// [`Layer`]s.
 ///
 /// [`Layer`]: crate::Layer
-/// [`Subscriber`]: https://docs.rs/tracing-core/latest/tracing_core/trait.Subscriber.html
+/// [`Subscriber`]: tracing_core::Subscriber
 #[derive(Clone)]
 pub struct Layered<L, I, S = I> {
     /// The layer.
@@ -63,6 +62,30 @@ pub struct Layered<L, I, S = I> {
 
 // === impl Layered ===
 
+impl<L, S> Layered<L, S>
+where
+    L: Layer<S>,
+    S: Subscriber,
+{
+    /// Returns `true` if this [`Subscriber`] is the same type as `T`.
+    pub fn is<T: Any>(&self) -> bool {
+        self.downcast_ref::<T>().is_some()
+    }
+
+    /// Returns some reference to this [`Subscriber`] value if it is of type `T`,
+    /// or `None` if it isn't.
+    pub fn downcast_ref<T: Any>(&self) -> Option<&T> {
+        unsafe {
+            let raw = self.downcast_raw(TypeId::of::<T>())?;
+            if raw.is_null() {
+                None
+            } else {
+                Some(&*(raw as *const T))
+            }
+        }
+    }
+}
+
 impl<L, S> Subscriber for Layered<L, S>
 where
     L: Layer<S>,
@@ -92,7 +115,11 @@ where
     }
 
     fn max_level_hint(&self) -> Option<LevelFilter> {
-        self.pick_level_hint(self.layer.max_level_hint(), self.inner.max_level_hint())
+        self.pick_level_hint(
+            self.layer.max_level_hint(),
+            self.inner.max_level_hint(),
+            super::subscriber_is_none(&self.inner),
+        )
     }
 
     fn new_span(&self, span: &span::Attributes<'_>) -> span::Id {
@@ -111,6 +138,16 @@ where
         self.layer.on_follows_from(span, follows, self.ctx());
     }
 
+    fn event_enabled(&self, event: &Event<'_>) -> bool {
+        if self.layer.event_enabled(event, self.ctx()) {
+            // if the outer layer enables the event, ask the inner subscriber.
+            self.inner.event_enabled(event)
+        } else {
+            // otherwise, the event is disabled by this layer
+            false
+        }
+    }
+
     fn event(&self, event: &Event<'_>) {
         self.inner.event(event);
         self.layer.on_event(event, self.ctx());
@@ -152,7 +189,7 @@ where
             #[cfg(all(feature = "registry", feature = "std"))]
             {
                 if let Some(g) = guard.as_mut() {
-                    g.is_closing()
+                    g.set_closing()
                 };
             }
 
@@ -207,6 +244,11 @@ where
     B: Layer<S>,
     S: Subscriber,
 {
+    fn on_register_dispatch(&self, subscriber: &Dispatch) {
+        self.layer.on_register_dispatch(subscriber);
+        self.inner.on_register_dispatch(subscriber);
+    }
+
     fn on_layer(&mut self, subscriber: &mut S) {
         self.layer.on_layer(subscriber);
         self.inner.on_layer(subscriber);
@@ -229,7 +271,11 @@ where
     }
 
     fn max_level_hint(&self) -> Option<LevelFilter> {
-        self.pick_level_hint(self.layer.max_level_hint(), self.inner.max_level_hint())
+        self.pick_level_hint(
+            self.layer.max_level_hint(),
+            self.inner.max_level_hint(),
+            super::layer_is_none(&self.inner),
+        )
     }
 
     #[inline]
@@ -251,6 +297,17 @@ where
     }
 
     #[inline]
+    fn event_enabled(&self, event: &Event<'_>, ctx: Context<'_, S>) -> bool {
+        if self.layer.event_enabled(event, ctx.clone()) {
+            // if the outer layer enables the event, ask the inner subscriber.
+            self.inner.event_enabled(event, ctx)
+        } else {
+            // otherwise, the event is disabled by this layer
+            false
+        }
+    }
+
+    #[inline]
     fn on_event(&self, event: &Event<'_>, ctx: Context<'_, S>) {
         self.inner.on_event(event, ctx.clone());
         self.layer.on_event(event, ctx);
@@ -386,7 +443,7 @@ where
             // (rather than calling into the inner type), clear the current
             // per-layer filter interest state.
             #[cfg(feature = "registry")]
-            drop(filter::FilterState::take_interest());
+            filter::FilterState::take_interest();
 
             return outer;
         }
@@ -421,6 +478,7 @@ where
         &self,
         outer_hint: Option<LevelFilter>,
         inner_hint: Option<LevelFilter>,
+        inner_is_none: bool,
     ) -> Option<LevelFilter> {
         if self.inner_is_registry {
             return outer_hint;
@@ -438,6 +496,31 @@ where
             return None;
         }
 
+        // If the layer is `Option::None`, then we
+        // want to short-circuit the layer underneath, if it
+        // returns `None`, to override the `None` layer returning
+        // `Some(OFF)`, which should ONLY apply when there are
+        // no other layers that return `None`. Note this
+        // `None` does not == `Some(TRACE)`, it means
+        // something more like: "whatever all the other
+        // layers agree on, default to `TRACE` if none
+        // have an opinion". We also choose do this AFTER
+        // we check for per-layer filters, which
+        // have their own logic.
+        //
+        // Also note that this does come at some perf cost, but
+        // this function is only called on initialization and
+        // subscriber reloading.
+        if super::layer_is_none(&self.layer) {
+            return cmp::max(outer_hint, Some(inner_hint?));
+        }
+
+        // Similarly, if the layer on the inside is `None` and it returned an
+        // `Off` hint, we want to override that with the outer hint.
+        if inner_is_none && inner_hint == Some(LevelFilter::OFF) {
+            return outer_hint;
+        }
+
         cmp::max(outer_hint, inner_hint)
     }
 }
diff --git a/vendor/tracing-subscriber-0.3.3/src/layer/mod.rs b/vendor/tracing-subscriber/src/layer/mod.rs
index f3f994490..bdc154301 100644
--- a/vendor/tracing-subscriber-0.3.3/src/layer/mod.rs
+++ b/vendor/tracing-subscriber/src/layer/mod.rs
@@ -19,7 +19,7 @@
 //! [`Subscriber`] behavior; it can _observe_ events and spans, but does not
 //! assign IDs.
 //!
-//! ## Composing Layers
+//! # Composing Layers
 //!
 //! Since a [`Layer`] does not implement a complete strategy for collecting
 //! traces, it must be composed with a `Subscriber` in order to be used. The
@@ -135,9 +135,245 @@
 //! [`Layer::with_subscriber`] as an implementation detail, as `with_subscriber`
 //! calls must be nested, leading to less clear code for the reader.
 //!
+//! ## Runtime Configuration With `Layer`s
+//!
+//! In some cases, a particular [`Layer`] may be enabled or disabled based on
+//! runtime configuration. This can introduce challenges, because the type of a
+//! layered [`Subscriber`] depends on which layers are added to it: if an `if`
+//! or `match` expression adds some [`Layer`] implementation in one branch,
+//! and other layers in another, the [`Subscriber`] values returned by those
+//! branches will have different types. For example, the following _will not_
+//! work:
+//!
+//! ```compile_fail
+//! # fn docs() -> Result<(), Box<dyn std::error::Error + 'static>> {
+//! # struct Config {
+//! #    is_prod: bool,
+//! #    path: &'static str,
+//! # }
+//! # let cfg = Config { is_prod: false, path: "debug.log" };
+//! use std::fs::File;
+//! use tracing_subscriber::{Registry, prelude::*};
+//!
+//! let stdout_log = tracing_subscriber::fmt::layer().pretty();
+//! let subscriber = Registry::default().with(stdout_log);
+//!
+//! // The compile error will occur here because the if and else
+//! // branches have different (and therefore incompatible) types.
+//! let subscriber = if cfg.is_prod {
+//!     let file = File::create(cfg.path)?;
+//!     let layer = tracing_subscriber::fmt::layer()
+//!         .json()
+//!         .with_writer(Arc::new(file));
+//!     layer.with(subscriber)
+//! } else {
+//!     layer
+//! };
+//!
+//! tracing::subscriber::set_global_default(subscriber)
+//!     .expect("Unable to set global subscriber");
+//! # Ok(()) }
+//! ```
+//!
+//! However, a [`Layer`] wrapped in an [`Option`] [also implements the `Layer`
+//! trait][option-impl]. This allows individual layers to be enabled or disabled at
+//! runtime while always producing a [`Subscriber`] of the same type. For
+//! example:
+//!
+//! ```
+//! # fn docs() -> Result<(), Box<dyn std::error::Error + 'static>> {
+//! # struct Config {
+//! #    is_prod: bool,
+//! #    path: &'static str,
+//! # }
+//! # let cfg = Config { is_prod: false, path: "debug.log" };
+//! use std::fs::File;
+//! use tracing_subscriber::{Registry, prelude::*};
+//!
+//! let stdout_log = tracing_subscriber::fmt::layer().pretty();
+//! let subscriber = Registry::default().with(stdout_log);
+//!
+//! // if `cfg.is_prod` is true, also log JSON-formatted logs to a file.
+//! let json_log = if cfg.is_prod {
+//!     let file = File::create(cfg.path)?;
+//!     let json_log = tracing_subscriber::fmt::layer()
+//!         .json()
+//!         .with_writer(file);
+//!     Some(json_log)
+//! } else {
+//!     None
+//! };
+//!
+//! // If `cfg.is_prod` is false, then `json` will be `None`, and this layer
+//! // will do nothing. However, the subscriber will still have the same type
+//! // regardless of whether the `Option`'s value is `None` or `Some`.
+//! let subscriber = subscriber.with(json_log);
+//!
+//! tracing::subscriber::set_global_default(subscriber)
+//!    .expect("Unable to set global subscriber");
+//! # Ok(()) }
+//! ```
+//!
+//! If a [`Layer`] may be one of several different types, note that [`Box<dyn
+//! Layer<S> + Send + Sync>` implements `Layer`][box-impl].
+//! This may be used to erase the type of a [`Layer`].
+//!
+//! For example, a function that configures a [`Layer`] to log to one of
+//! several outputs might return a `Box<dyn Layer<S> + Send + Sync + 'static>`:
+//! ```
+//! use tracing_subscriber::{
+//!     Layer,
+//!     registry::LookupSpan,
+//!     prelude::*,
+//! };
+//! use std::{path::PathBuf, fs::File, io};
+//!
+//! /// Configures whether logs are emitted to a file, to stdout, or to stderr.
+//! pub enum LogConfig {
+//!     File(PathBuf),
+//!     Stdout,
+//!     Stderr,
+//! }
+//!
+//! impl LogConfig {
+//!     pub fn layer<S>(self) -> Box<dyn Layer<S> + Send + Sync + 'static>
+//!     where
+//!         S: tracing_core::Subscriber,
+//!         for<'a> S: LookupSpan<'a>,
+//!     {
+//!         // Shared configuration regardless of where logs are output to.
+//!         let fmt = tracing_subscriber::fmt::layer()
+//!             .with_target(true)
+//!             .with_thread_names(true);
+//!
+//!         // Configure the writer based on the desired log target:
+//!         match self {
+//!             LogConfig::File(path) => {
+//!                 let file = File::create(path).expect("failed to create log file");
+//!                 Box::new(fmt.with_writer(file))
+//!             },
+//!             LogConfig::Stdout => Box::new(fmt.with_writer(io::stdout)),
+//!             LogConfig::Stderr => Box::new(fmt.with_writer(io::stderr)),
+//!         }
+//!     }
+//! }
+//!
+//! let config = LogConfig::Stdout;
+//! tracing_subscriber::registry()
+//!     .with(config.layer())
+//!     .init();
+//! ```
+//!
+//! The [`Layer::boxed`] method is provided to make boxing a `Layer`
+//! more convenient, but [`Box::new`] may be used as well.
+//!
+//! When the number of `Layer`s varies at runtime, note that a
+//! [`Vec<L> where L: Layer` also implements `Layer`][vec-impl]. This
+//! can be used to add a variable number of `Layer`s to a `Subscriber`:
+//!
+//! ```
+//! use tracing_subscriber::{Layer, prelude::*};
+//! struct MyLayer {
+//!     // ...
+//! }
+//! # impl MyLayer { fn new() -> Self { Self {} }}
+//!
+//! impl<S: tracing_core::Subscriber> Layer<S> for MyLayer {
+//!     // ...
+//! }
+//!
+//! /// Returns how many layers we need
+//! fn how_many_layers() -> usize {
+//!     // ...
+//!     # 3
+//! }
+//!
+//! // Create a variable-length `Vec` of layers
+//! let mut layers = Vec::new();
+//! for _ in 0..how_many_layers() {
+//!     layers.push(MyLayer::new());
+//! }
+//!
+//! tracing_subscriber::registry()
+//!     .with(layers)
+//!     .init();
+//! ```
+//!
+//! If a variable number of `Layer` is needed and those `Layer`s have
+//! different types, a `Vec` of [boxed `Layer` trait objects][box-impl] may
+//! be used. For example:
+//!
+//! ```
+//! use tracing_subscriber::{filter::LevelFilter, Layer, prelude::*};
+//! use std::fs::File;
+//! # fn main() -> Result<(), Box<dyn std::error::Error>> {
+//! struct Config {
+//!     enable_log_file: bool,
+//!     enable_stdout: bool,
+//!     enable_stderr: bool,
+//!     // ...
+//! }
+//! # impl Config {
+//! #    fn from_config_file()-> Result<Self, Box<dyn std::error::Error>> {
+//! #         // don't enable the log file so that the example doesn't actually create it
+//! #         Ok(Self { enable_log_file: false, enable_stdout: true, enable_stderr: true })
+//! #    }
+//! # }
+//!
+//! let cfg = Config::from_config_file()?;
+//!
+//! // Based on our dynamically loaded config file, create any number of layers:
+//! let mut layers = Vec::new();
+//!
+//! if cfg.enable_log_file {
+//!     let file = File::create("myapp.log")?;
+//!     let layer = tracing_subscriber::fmt::layer()
+//!         .with_thread_names(true)
+//!         .with_target(true)
+//!         .json()
+//!         .with_writer(file)
+//!         // Box the layer as a type-erased trait object, so that it can
+//!         // be pushed to the `Vec`.
+//!         .boxed();
+//!     layers.push(layer);
+//! }
+//!
+//! if cfg.enable_stdout {
+//!     let layer = tracing_subscriber::fmt::layer()
+//!         .pretty()
+//!         .with_filter(LevelFilter::INFO)
+//!         // Box the layer as a type-erased trait object, so that it can
+//!         // be pushed to the `Vec`.
+//!         .boxed();
+//!     layers.push(layer);
+//! }
+//!
+//! if cfg.enable_stdout {
+//!     let layer = tracing_subscriber::fmt::layer()
+//!         .with_target(false)
+//!         .with_filter(LevelFilter::WARN)
+//!         // Box the layer as a type-erased trait object, so that it can
+//!         // be pushed to the `Vec`.
+//!         .boxed();
+//!     layers.push(layer);
+//! }
+//!
+//! tracing_subscriber::registry()
+//!     .with(layers)
+//!     .init();
+//!# Ok(()) }
+//! ```
+//!
+//! Finally, if the number of layers _changes_ at runtime, a `Vec` of
+//! subscribers can be used alongside the [`reload`](crate::reload) module to
+//! add or remove subscribers dynamically at runtime.
+//!
+//! [option-impl]: Layer#impl-Layer<S>-for-Option<L>
+//! [box-impl]: Layer#impl-Layer%3CS%3E-for-Box%3Cdyn%20Layer%3CS%3E%20+%20Send%20+%20Sync%3E
+//! [vec-impl]: Layer#impl-Layer<S>-for-Vec<L>
 //! [prelude]: crate::prelude
 //!
-//! ## Recording Traces
+//! # Recording Traces
 //!
 //! The [`Layer`] trait defines a set of methods for consuming notifications from
 //! tracing instrumentation, which are generally equivalent to the similarly
@@ -146,7 +382,7 @@
 //! information provided by the wrapped subscriber (such as [the current span])
 //! to the layer.
 //!
-//! ## Filtering with `Layer`s
+//! # Filtering with `Layer`s
 //!
 //! As well as strategies for handling trace events, the `Layer` trait may also
 //! be used to represent composable _filters_. This allows the determination of
@@ -158,7 +394,7 @@
 //! combined with _per-layer filters_ that control what spans and events are
 //! recorded by those layers.
 //!
-//! ### Global Filtering
+//! ## Global Filtering
 //!
 //! A `Layer` that implements a filtering strategy should override the
 //! [`register_callsite`] and/or [`enabled`] methods. It may also choose to implement
@@ -179,7 +415,29 @@
 //! [`Interest::never()`] from its [`register_callsite`] method, filter
 //! evaluation will short-circuit and the span or event will be disabled.
 //!
-//! ### Per-Layer Filtering
+//! ### Enabling Interest
+//!
+//! Whenever an tracing event (or span) is emitted, it goes through a number of
+//! steps to determine how and how much it should be processed. The earlier an
+//! event is disabled, the less work has to be done to process the event, so
+//! `Layer`s that implement filtering should attempt to disable unwanted
+//! events as early as possible. In order, each event checks:
+//!
+//! - [`register_callsite`], once per callsite (roughly: once per time that
+//!   `event!` or `span!` is written in the source code; this is cached at the
+//!   callsite). See [`Subscriber::register_callsite`] and
+//!   [`tracing_core::callsite`] for a summary of how this behaves.
+//! - [`enabled`], once per emitted event (roughly: once per time that `event!`
+//!   or `span!` is *executed*), and only if `register_callsite` regesters an
+//!   [`Interest::sometimes`]. This is the main customization point to globally
+//!   filter events based on their [`Metadata`]. If an event can be disabled
+//!   based only on [`Metadata`], it should be, as this allows the construction
+//!   of the actual `Event`/`Span` to be skipped.
+//! - For events only (and not spans), [`event_enabled`] is called just before
+//!   processing the event. This gives layers one last chance to say that
+//!   an event should be filtered out, now that the event's fields are known.
+//!
+//! ## Per-Layer Filtering
 //!
 //! **Note**: per-layer filtering APIs currently require the [`"registry"` crate
 //! feature flag][feat] to be enabled.
@@ -393,94 +651,16 @@
 //! # Ok(()) }
 //! ```
 //!
-//! ## Runtime Configuration With Layers
-//!
-//! In some cases, a particular [`Layer`] may be enabled or disabled based on
-//! runtime configuration. This can introduce challenges, because the type of a
-//! layered [`Subscriber`] depends on which layers are added to it: if an `if`
-//! or `match` expression adds some [`Layer`]s in one branch and other layers
-//! in another, the [`Subscriber`] values returned by those branches will have
-//! different types. For example, the following _will not_ work:
-//!
-//! ```compile_fail
-//! # fn docs() -> Result<(), Box<dyn std::error::Error + 'static>> {
-//! # struct Config {
-//! #    is_prod: bool,
-//! #    path: &'static str,
-//! # }
-//! # let cfg = Config { is_prod: false, path: "debug.log" };
-//! use std::{fs::File, sync::Arc};
-//! use tracing_subscriber::{Registry, prelude::*};
-//!
-//! let stdout_log = tracing_subscriber::fmt::layer().pretty();
-//! let subscriber = Registry::default().with(stdout_log);
-//!
-//! // The compile error will occur here because the if and else
-//! // branches have different (and therefore incompatible) types.
-//! let subscriber = if cfg.is_prod {
-//!     let file = File::create(cfg.path)?;
-//!     let layer = tracing_subscriber::fmt::layer()
-//!         .json()
-//!         .with_writer(Arc::new(file));
-//!     subscriber.with(layer)
-//! } else {
-//!     subscriber
-//! };
-//!
-//! tracing::subscriber::set_global_default(subscriber)
-//!     .expect("Unable to set global subscriber");
-//! # Ok(()) }
-//! ```
-//!
-//! However, a [`Layer`] wrapped in an [`Option`] [also implements the `Layer`
-//! trait][option-impl]. This allows individual layers to be enabled or disabled at
-//! runtime while always producing a [`Subscriber`] of the same type. For
-//! example:
-//!
-//! ```
-//! # fn docs() -> Result<(), Box<dyn std::error::Error + 'static>> {
-//! # struct Config {
-//! #    is_prod: bool,
-//! #    path: &'static str,
-//! # }
-//! # let cfg = Config { is_prod: false, path: "debug.log" };
-//! use std::{fs::File, sync::Arc};
-//! use tracing_subscriber::{Registry, prelude::*};
-//!
-//! let stdout_log = tracing_subscriber::fmt::layer().pretty();
-//! let subscriber = Registry::default().with(stdout_log);
-//!
-//! // if `cfg.is_prod` is true, also log JSON-formatted logs to a file.
-//! let json_log = if cfg.is_prod {
-//!     let file = File::create(cfg.path)?;
-//!     let json_log = tracing_subscriber::fmt::layer()
-//!         .json()
-//!         .with_writer(Arc::new(file));
-//!     Some(json_log)
-//! } else {   
-//!     None
-//! };
-//!
-//! // If `cfg.is_prod` is false, then `json` will be `None`, and this layer
-//! // will do nothing. However, the subscriber will still have the same type
-//! // regardless of whether the `Option`'s value is `None` or `Some`.
-//! let subscriber = subscriber.with(json_log);
-//!
-//! tracing::subscriber::set_global_default(subscriber)
-//!    .expect("Unable to set global subscriber");
-//! # Ok(()) }
-//! ```
-//!
-//! [`Subscriber`]: https://docs.rs/tracing-core/latest/tracing_core/subscriber/trait.Subscriber.html
-//! [span IDs]: https://docs.rs/tracing-core/latest/tracing_core/span/struct.Id.html
+//! [`Subscriber`]: tracing_core::subscriber::Subscriber
+//! [span IDs]: tracing_core::span::Id
 //! [the current span]: Context::current_span
 //! [`register_callsite`]: Layer::register_callsite
 //! [`enabled`]: Layer::enabled
+//! [`event_enabled`]: Layer::event_enabled
 //! [`on_enter`]: Layer::on_enter
 //! [`Layer::register_callsite`]: Layer::register_callsite
 //! [`Layer::enabled`]: Layer::enabled
-//! [`Interest::never()`]: https://docs.rs/tracing-core/latest/tracing_core/subscriber/struct.Interest.html#method.never
-//! [option-impl]: crate::layer::Layer#impl-Layer<S>-for-Option<L>
+//! [`Interest::never()`]: tracing_core::subscriber::Interest::never()
 //! [`Filtered`]: crate::filter::Filtered
 //! [`filter`]: crate::filter
 //! [`Targets`]: crate::filter::Targets
@@ -498,7 +678,7 @@ use tracing_core::{
     metadata::Metadata,
     span,
     subscriber::{Interest, Subscriber},
-    Event, LevelFilter,
+    Dispatch, Event, LevelFilter,
 };
 
 use core::any::TypeId;
@@ -531,6 +711,31 @@ where
     S: Subscriber,
     Self: 'static,
 {
+    /// Performs late initialization when installing this layer as a
+    /// [`Subscriber`].
+    ///
+    /// ## Avoiding Memory Leaks
+    ///
+    /// `Layer`s should not store the [`Dispatch`] pointing to the [`Subscriber`]
+    /// that they are a part of. Because the `Dispatch` owns the `Subscriber`,
+    /// storing the `Dispatch` within the `Subscriber` will create a reference
+    /// count cycle, preventing the `Dispatch` from ever being dropped.
+    ///
+    /// Instead, when it is necessary to store a cyclical reference to the
+    /// `Dispatch` within a `Layer`, use [`Dispatch::downgrade`] to convert a
+    /// `Dispatch` into a [`WeakDispatch`]. This type is analogous to
+    /// [`std::sync::Weak`], and does not create a reference count cycle. A
+    /// [`WeakDispatch`] can be stored within a subscriber without causing a
+    /// memory leak, and can be [upgraded] into a `Dispatch` temporarily when
+    /// the `Dispatch` must be accessed by the subscriber.
+    ///
+    /// [`WeakDispatch`]: tracing_core::dispatcher::WeakDispatch
+    /// [upgraded]: tracing_core::dispatcher::WeakDispatch::upgrade
+    /// [`Subscriber`]: tracing_core::Subscriber
+    fn on_register_dispatch(&self, collector: &Dispatch) {
+        let _ = collector;
+    }
+
     /// Performs late initialization when attaching a `Layer` to a
     /// [`Subscriber`].
     ///
@@ -592,15 +797,15 @@ where
     /// globally enable or disable those callsites, it should always return
     /// [`Interest::always()`].
     ///
-    /// [`Interest`]: https://docs.rs/tracing-core/latest/tracing_core/struct.Interest.html
-    /// [`Subscriber::register_callsite`]: https://docs.rs/tracing-core/latest/tracing_core/trait.Subscriber.html#method.register_callsite
-    /// [`Interest::never()`]: https://docs.rs/tracing-core/latest/tracing_core/subscriber/struct.Interest.html#method.never
-    /// [`Interest::always()`]: https://docs.rs/tracing-core/latest/tracing_core/subscriber/struct.Interest.html#method.always
-    /// [`self.enabled`]: #method.enabled
-    /// [`Layer::enabled`]: #method.enabled
-    /// [`on_event`]: #method.on_event
-    /// [`on_enter`]: #method.on_enter
-    /// [`on_exit`]: #method.on_exit
+    /// [`Interest`]: tracing_core::Interest
+    /// [`Subscriber::register_callsite`]: tracing_core::Subscriber::register_callsite()
+    /// [`Interest::never()`]: tracing_core::subscriber::Interest::never()
+    /// [`Interest::always()`]: tracing_core::subscriber::Interest::always()
+    /// [`self.enabled`]: Layer::enabled()
+    /// [`Layer::enabled`]: Layer::enabled()
+    /// [`on_event`]: Layer::on_event()
+    /// [`on_enter`]: Layer::on_enter()
+    /// [`on_exit`]: Layer::on_exit()
     /// [the trait-level documentation]: #filtering-with-layers
     fn register_callsite(&self, metadata: &'static Metadata<'static>) -> Interest {
         if self.enabled(metadata, Context::none()) {
@@ -635,13 +840,12 @@ where
     /// See [the trait-level documentation] for more information on filtering
     /// with `Layer`s.
     ///
-    /// [`Interest`]: https://docs.rs/tracing-core/latest/tracing_core/struct.Interest.html
-    /// [`Context`]: ../struct.Context.html
-    /// [`Subscriber::enabled`]: https://docs.rs/tracing-core/latest/tracing_core/trait.Subscriber.html#method.enabled
-    /// [`Layer::register_callsite`]: #method.register_callsite
-    /// [`on_event`]: #method.on_event
-    /// [`on_enter`]: #method.on_enter
-    /// [`on_exit`]: #method.on_exit
+    /// [`Interest`]: tracing_core::Interest
+    /// [`Subscriber::enabled`]: tracing_core::Subscriber::enabled()
+    /// [`Layer::register_callsite`]: Layer::register_callsite()
+    /// [`on_event`]: Layer::on_event()
+    /// [`on_enter`]: Layer::on_enter()
+    /// [`on_exit`]: Layer::on_exit()
     /// [the trait-level documentation]: #filtering-with-layers
     fn enabled(&self, metadata: &Metadata<'_>, ctx: Context<'_, S>) -> bool {
         let _ = (metadata, ctx);
@@ -676,6 +880,31 @@ where
     // seems like a good future-proofing measure as it may grow other methods later...
     fn on_follows_from(&self, _span: &span::Id, _follows: &span::Id, _ctx: Context<'_, S>) {}
 
+    /// Called before [`on_event`], to determine if `on_event` should be called.
+    ///
+    /// <div class="example-wrap" style="display:inline-block">
+    /// <pre class="ignore" style="white-space:normal;font:inherit;">
+    ///
+    /// **Note**: This method determines whether an event is globally enabled,
+    /// *not* whether the individual `Layer` will be notified about the
+    /// event. This is intended to be used by `Layer`s that implement
+    /// filtering for the entire stack. `Layer`s which do not wish to be
+    /// notified about certain events but do not wish to globally disable them
+    /// should ignore those events in their [on_event][Self::on_event].
+    ///
+    /// </pre></div>
+    ///
+    /// See [the trait-level documentation] for more information on filtering
+    /// with `Layer`s.
+    ///
+    /// [`on_event`]: Self::on_event
+    /// [`Interest`]: tracing_core::Interest
+    /// [the trait-level documentation]: #filtering-with-layers
+    #[inline] // collapse this to a constant please mrs optimizer
+    fn event_enabled(&self, _event: &Event<'_>, _ctx: Context<'_, S>) -> bool {
+        true
+    }
+
     /// Notifies this layer that an event has occurred.
     fn on_event(&self, _event: &Event<'_>, _ctx: Context<'_, S>) {}
 
@@ -840,7 +1069,7 @@ where
     ///     .with_subscriber(MySubscriber::new());
     ///```
     ///
-    /// [`Subscriber`]: https://docs.rs/tracing-core/latest/tracing_core/trait.Subscriber.html
+    /// [`Subscriber`]: tracing_core::Subscriber
     fn with_subscriber(mut self, mut inner: S) -> Layered<Self, S>
     where
         Self: Sized,
@@ -857,7 +1086,7 @@ where
     /// per-layer filtering.
     ///
     /// [`Filtered`]: crate::filter::Filtered
-    /// [plf]: #per-layer-filtering
+    /// [plf]: crate::layer#per-layer-filtering
     #[cfg(all(feature = "registry", feature = "std"))]
     #[cfg_attr(docsrs, doc(cfg(all(feature = "registry", feature = "std"))))]
     fn with_filter<F>(self, filter: F) -> filter::Filtered<Self, F, S>
@@ -868,6 +1097,131 @@ where
         filter::Filtered::new(self, filter)
     }
 
+    /// Erases the type of this [`Layer`], returning a [`Box`]ed `dyn
+    /// Layer` trait object.
+    ///
+    /// This can be used when a function returns a `Layer` which may be of
+    /// one of several types, or when a `Layer` subscriber has a very long type
+    /// signature.
+    ///
+    /// # Examples
+    ///
+    /// The following example will *not* compile, because the value assigned to
+    /// `log_layer` may have one of several different types:
+    ///
+    /// ```compile_fail
+    /// # fn main() -> Result<(), Box<dyn std::error::Error>> {
+    /// use tracing_subscriber::{Layer, filter::LevelFilter, prelude::*};
+    /// use std::{path::PathBuf, fs::File, io};
+    ///
+    /// /// Configures whether logs are emitted to a file, to stdout, or to stderr.
+    /// pub enum LogConfig {
+    ///     File(PathBuf),
+    ///     Stdout,
+    ///     Stderr,
+    /// }
+    ///
+    /// let config = // ...
+    ///     # LogConfig::Stdout;
+    ///
+    /// // Depending on the config, construct a layer of one of several types.
+    /// let log_layer = match config {
+    ///     // If logging to a file, use a maximally-verbose configuration.
+    ///     LogConfig::File(path) => {
+    ///         let file = File::create(path)?;
+    ///         tracing_subscriber::fmt::layer()
+    ///             .with_thread_ids(true)
+    ///             .with_thread_names(true)
+    ///             // Selecting the JSON logging format changes the layer's
+    ///             // type.
+    ///             .json()
+    ///             .with_span_list(true)
+    ///             // Setting the writer to use our log file changes the
+    ///             // layer's type again.
+    ///             .with_writer(file)
+    ///     },
+    ///
+    ///     // If logging to stdout, use a pretty, human-readable configuration.
+    ///     LogConfig::Stdout => tracing_subscriber::fmt::layer()
+    ///         // Selecting the "pretty" logging format changes the
+    ///         // layer's type!
+    ///         .pretty()
+    ///         .with_writer(io::stdout)
+    ///         // Add a filter based on the RUST_LOG environment variable;
+    ///         // this changes the type too!
+    ///         .and_then(tracing_subscriber::EnvFilter::from_default_env()),
+    ///
+    ///     // If logging to stdout, only log errors and warnings.
+    ///     LogConfig::Stderr => tracing_subscriber::fmt::layer()
+    ///         // Changing the writer changes the layer's type
+    ///         .with_writer(io::stderr)
+    ///         // Only log the `WARN` and `ERROR` levels. Adding a filter
+    ///         // changes the layer's type to `Filtered<LevelFilter, ...>`.
+    ///         .with_filter(LevelFilter::WARN),
+    /// };
+    ///
+    /// tracing_subscriber::registry()
+    ///     .with(log_layer)
+    ///     .init();
+    /// # Ok(()) }
+    /// ```
+    ///
+    /// However, adding a call to `.boxed()` after each match arm erases the
+    /// layer's type, so this code *does* compile:
+    ///
+    /// ```
+    /// # fn main() -> Result<(), Box<dyn std::error::Error>> {
+    /// # use tracing_subscriber::{Layer, filter::LevelFilter, prelude::*};
+    /// # use std::{path::PathBuf, fs::File, io};
+    /// # pub enum LogConfig {
+    /// #    File(PathBuf),
+    /// #    Stdout,
+    /// #    Stderr,
+    /// # }
+    /// # let config = LogConfig::Stdout;
+    /// let log_layer = match config {
+    ///     LogConfig::File(path) => {
+    ///         let file = File::create(path)?;
+    ///         tracing_subscriber::fmt::layer()
+    ///             .with_thread_ids(true)
+    ///             .with_thread_names(true)
+    ///             .json()
+    ///             .with_span_list(true)
+    ///             .with_writer(file)
+    ///             // Erase the type by boxing the layer
+    ///             .boxed()
+    ///     },
+    ///
+    ///     LogConfig::Stdout => tracing_subscriber::fmt::layer()
+    ///         .pretty()
+    ///         .with_writer(io::stdout)
+    ///         .and_then(tracing_subscriber::EnvFilter::from_default_env())
+    ///         // Erase the type by boxing the layer
+    ///         .boxed(),
+    ///
+    ///     LogConfig::Stderr => tracing_subscriber::fmt::layer()
+    ///         .with_writer(io::stderr)
+    ///         .with_filter(LevelFilter::WARN)
+    ///         // Erase the type by boxing the layer
+    ///         .boxed(),
+    /// };
+    ///
+    /// tracing_subscriber::registry()
+    ///     .with(log_layer)
+    ///     .init();
+    /// # Ok(()) }
+    /// ```
+    #[cfg(any(feature = "alloc", feature = "std"))]
+    #[cfg_attr(docsrs, doc(cfg(any(feature = "alloc", feature = "std"))))]
+    fn boxed(self) -> Box<dyn Layer<S> + Send + Sync + 'static>
+    where
+        Self: Sized,
+        Self: Layer<S> + Send + Sync + 'static,
+        S: Subscriber,
+    {
+        Box::new(self)
+    }
+
     #[doc(hidden)]
     unsafe fn downcast_raw(&self, id: TypeId) -> Option<*const ()> {
         if id == TypeId::of::<Self>() {
@@ -880,6 +1234,7 @@ where
 
 feature! {
     #![all(feature = "registry", feature = "std")]
+
     /// A per-[`Layer`] filter that determines whether a span or event is enabled
     /// for an individual layer.
     ///
@@ -1022,6 +1377,26 @@ feature! {
             Interest::sometimes()
         }
 
+        /// Called before the filtered [`Layer]'s [`on_event`], to determine if
+        /// `on_event` should be called.
+        ///
+        /// This gives a chance to filter events based on their fields. Note,
+        /// however, that this *does not* override [`enabled`], and is not even
+        /// called if [`enabled`] returns `false`.
+        ///
+        /// ## Default Implementation
+        ///
+        /// By default, this method returns `true`, indicating that no events are
+        /// filtered out based on their fields.
+        ///
+        /// [`enabled`]: crate::layer::Filter::enabled
+        /// [`on_event`]: crate::layer::Layer::on_event
+        #[inline] // collapse this to a constant please mrs optimizer
+        fn event_enabled(&self, event: &Event<'_>, cx: &Context<'_, S>) -> bool {
+            let _ = (event, cx);
+            true
+        }
+
         /// Returns an optional hint of the highest [verbosity level][level] that
         /// this `Filter` will enable.
         ///
@@ -1054,6 +1429,51 @@ feature! {
         fn max_level_hint(&self) -> Option<LevelFilter> {
             None
         }
+
+        /// Notifies this filter that a new span was constructed with the given
+        /// `Attributes` and `Id`.
+        ///
+        /// By default, this method does nothing. `Filter` implementations that
+        /// need to be notified when new spans are created can override this
+        /// method.
+        fn on_new_span(&self, attrs: &span::Attributes<'_>, id: &span::Id, ctx: Context<'_, S>) {
+            let _ = (attrs, id, ctx);
+        }
+
+
+        /// Notifies this filter that a span with the given `Id` recorded the given
+        /// `values`.
+        ///
+        /// By default, this method does nothing. `Filter` implementations that
+        /// need to be notified when new spans are created can override this
+        /// method.
+        fn on_record(&self, id: &span::Id, values: &span::Record<'_>, ctx: Context<'_, S>) {
+            let _ = (id, values, ctx);
+        }
+
+        /// Notifies this filter that a span with the given ID was entered.
+        ///
+        /// By default, this method does nothing. `Filter` implementations that
+        /// need to be notified when a span is entered can override this method.
+        fn on_enter(&self, id: &span::Id, ctx: Context<'_, S>) {
+            let _ = (id, ctx);
+        }
+
+        /// Notifies this filter that a span with the given ID was exited.
+        ///
+        /// By default, this method does nothing. `Filter` implementations that
+        /// need to be notified when a span is exited can override this method.
+        fn on_exit(&self, id: &span::Id, ctx: Context<'_, S>) {
+            let _ = (id, ctx);
+        }
+
+        /// Notifies this filter that a span with the given ID has been closed.
+        ///
+        /// By default, this method does nothing. `Filter` implementations that
+        /// need to be notified when a span is closed can override this method.
+        fn on_close(&self, id: span::Id, ctx: Context<'_, S>) {
+            let _ = (id, ctx);
+        }
     }
 }
 
@@ -1077,6 +1497,47 @@ pub struct Identity {
 
 // === impl Layer ===
 
+#[derive(Clone, Copy)]
+pub(crate) struct NoneLayerMarker(());
+static NONE_LAYER_MARKER: NoneLayerMarker = NoneLayerMarker(());
+
+/// Is a type implementing `Layer` `Option::<_>::None`?
+pub(crate) fn layer_is_none<L, S>(layer: &L) -> bool
+where
+    L: Layer<S>,
+    S: Subscriber,
+{
+    unsafe {
+        // Safety: we're not actually *doing* anything with this pointer ---
+        // this only care about the `Option`, which is essentially being used
+        // as a bool. We can rely on the pointer being valid, because it is
+        // a crate-private type, and is only returned by the `Layer` impl
+        // for `Option`s. However, even if the layer *does* decide to be
+        // evil and give us an invalid pointer here, that's fine, because we'll
+        // never actually dereference it.
+        layer.downcast_raw(TypeId::of::<NoneLayerMarker>())
+    }
+    .is_some()
+}
+
+/// Is a type implementing `Subscriber` `Option::<_>::None`?
+pub(crate) fn subscriber_is_none<S>(subscriber: &S) -> bool
+where
+    S: Subscriber,
+{
+    unsafe {
+        // Safety: we're not actually *doing* anything with this pointer ---
+        // this only care about the `Option`, which is essentially being used
+        // as a bool. We can rely on the pointer being valid, because it is
+        // a crate-private type, and is only returned by the `Layer` impl
+        // for `Option`s. However, even if the subscriber *does* decide to be
+        // evil and give us an invalid pointer here, that's fine, because we'll
+        // never actually dereference it.
+        subscriber.downcast_raw(TypeId::of::<NoneLayerMarker>())
+    }
+    .is_some()
+}
+
 impl<L, S> Layer<S> for Option<L>
 where
     L: Layer<S>,
@@ -1115,7 +1576,11 @@ where
     fn max_level_hint(&self) -> Option<LevelFilter> {
         match self {
             Some(ref inner) => inner.max_level_hint(),
-            None => None,
+            None => {
+                // There is no inner layer, so this layer will
+                // never enable anything.
+                Some(LevelFilter::OFF)
+            }
         }
     }
 
@@ -1134,6 +1599,14 @@ where
     }
 
     #[inline]
+    fn event_enabled(&self, event: &Event<'_>, ctx: Context<'_, S>) -> bool {
+        match self {
+            Some(ref inner) => inner.event_enabled(event, ctx),
+            None => true,
+        }
+    }
+
+    #[inline]
     fn on_event(&self, event: &Event<'_>, ctx: Context<'_, S>) {
         if let Some(ref inner) = self {
             inner.on_event(event, ctx);
@@ -1173,6 +1646,8 @@ where
     unsafe fn downcast_raw(&self, id: TypeId) -> Option<*const ()> {
         if id == TypeId::of::<Self>() {
             Some(self as *const _ as *const ())
+        } else if id == TypeId::of::<NoneLayerMarker>() && self.is_none() {
+            Some(&NONE_LAYER_MARKER as *const _ as *const ())
         } else {
             self.as_ref().and_then(|inner| inner.downcast_raw(id))
         }
@@ -1181,10 +1656,17 @@ where
 
 feature! {
     #![any(feature = "std", feature = "alloc")]
+    #[cfg(not(feature = "std"))]
+    use alloc::vec::Vec;
 
     macro_rules! layer_impl_body {
         () => {
             #[inline]
+            fn on_register_dispatch(&self, subscriber: &Dispatch) {
+                self.deref().on_register_dispatch(subscriber);
+            }
+
+            #[inline]
             fn on_layer(&mut self, subscriber: &mut S) {
                 self.deref_mut().on_layer(subscriber);
             }
@@ -1220,6 +1702,11 @@ feature! {
             }
 
             #[inline]
+            fn event_enabled(&self, event: &Event<'_>, ctx: Context<'_, S>) -> bool {
+                self.deref().event_enabled(event, ctx)
+            }
+
+            #[inline]
             fn on_event(&self, event: &Event<'_>, ctx: Context<'_, S>) {
                 self.deref().on_event(event, ctx)
             }
@@ -1266,6 +1753,125 @@ feature! {
     {
         layer_impl_body! {}
     }
+
+
+
+    impl<S, L> Layer<S> for Vec<L>
+    where
+        L: Layer<S>,
+        S: Subscriber,
+    {
+
+        fn on_layer(&mut self, subscriber: &mut S) {
+            for l in self {
+                l.on_layer(subscriber);
+            }
+        }
+
+        fn register_callsite(&self, metadata: &'static Metadata<'static>) -> Interest {
+            // Return highest level of interest.
+            let mut interest = Interest::never();
+            for l in self {
+                let new_interest = l.register_callsite(metadata);
+                if (interest.is_sometimes() && new_interest.is_always())
+                    || (interest.is_never() && !new_interest.is_never())
+                {
+                    interest = new_interest;
+                }
+            }
+
+            interest
+        }
+
+        fn enabled(&self, metadata: &Metadata<'_>, ctx: Context<'_, S>) -> bool {
+            self.iter().all(|l| l.enabled(metadata, ctx.clone()))
+        }
+
+        fn event_enabled(&self, event: &Event<'_>, ctx: Context<'_, S>) -> bool {
+            self.iter().all(|l| l.event_enabled(event, ctx.clone()))
+        }
+
+        fn on_new_span(&self, attrs: &span::Attributes<'_>, id: &span::Id, ctx: Context<'_, S>) {
+            for l in self {
+                l.on_new_span(attrs, id, ctx.clone());
+            }
+        }
+
+        fn max_level_hint(&self) -> Option<LevelFilter> {
+            // Default to `OFF` if there are no inner layers.
+            let mut max_level = LevelFilter::OFF;
+            for l in self {
+                // NOTE(eliza): this is slightly subtle: if *any* layer
+                // returns `None`, we have to return `None`, assuming there is
+                // no max level hint, since that particular layer cannot
+                // provide a hint.
+                let hint = l.max_level_hint()?;
+                max_level = core::cmp::max(hint, max_level);
+            }
+            Some(max_level)
+        }
+
+        fn on_record(&self, span: &span::Id, values: &span::Record<'_>, ctx: Context<'_, S>) {
+            for l in self {
+                l.on_record(span, values, ctx.clone())
+            }
+        }
+
+        fn on_follows_from(&self, span: &span::Id, follows: &span::Id, ctx: Context<'_, S>) {
+            for l in self {
+                l.on_follows_from(span, follows, ctx.clone());
+            }
+        }
+
+        fn on_event(&self, event: &Event<'_>, ctx: Context<'_, S>) {
+            for l in self {
+                l.on_event(event, ctx.clone());
+            }
+        }
+
+        fn on_enter(&self, id: &span::Id, ctx: Context<'_, S>) {
+            for l in self {
+                l.on_enter(id, ctx.clone());
+            }
+        }
+
+        fn on_exit(&self, id: &span::Id, ctx: Context<'_, S>) {
+            for l in self {
+                l.on_exit(id, ctx.clone());
+            }
+        }
+
+        fn on_close(&self, id: span::Id, ctx: Context<'_, S>) {
+            for l in self {
+                l.on_close(id.clone(), ctx.clone());
+            }
+        }
+
+        #[doc(hidden)]
+        unsafe fn downcast_raw(&self, id: TypeId) -> Option<*const ()> {
+            // If downcasting to `Self`, return a pointer to `self`.
+            if id == TypeId::of::<Self>() {
+                return Some(self as *const _ as *const ());
+            }
+
+            // Someone is looking for per-layer filters. But, this `Vec`
+            // might contain layers with per-layer filters *and*
+            // layers without filters. It should only be treated as a
+            // per-layer-filtered layer if *all* its layers have
+            // per-layer filters.
+            // XXX(eliza): it's a bummer we have to do this linear search every
+            // time. It would be nice if this could be cached, but that would
+            // require replacing the `Vec` impl with an impl for a newtype...
+            if filter::is_plf_downcast_marker(id) && self.iter().any(|s| s.downcast_raw(id).is_none()) {
+                return None;
+            }
+
+            // Otherwise, return the first child of `self` that downcaasts to
+            // the selected type, if any.
+            // XXX(eliza): hope this is reasonable lol
+            self.iter().find_map(|l| l.downcast_raw(id))
+        }
+    }
 }
 
 // === impl SubscriberExt ===
diff --git a/vendor/tracing-subscriber-0.3.3/src/layer/tests.rs b/vendor/tracing-subscriber/src/layer/tests.rs
index d7ad61769..d7ad61769 100644
--- a/vendor/tracing-subscriber-0.3.3/src/layer/tests.rs
+++ b/vendor/tracing-subscriber/src/layer/tests.rs
diff --git a/vendor/tracing-subscriber-0.3.3/src/lib.rs b/vendor/tracing-subscriber/src/lib.rs
index 563a86dee..808923007 100644
--- a/vendor/tracing-subscriber-0.3.3/src/lib.rs
+++ b/vendor/tracing-subscriber/src/lib.rs
@@ -10,7 +10,7 @@
 //! `tracing-subscriber` is intended for use by both `Subscriber` authors and
 //! application authors using `tracing` to instrument their applications.
 //!
-//! *Compiler support: [requires `rustc` 1.42+][msrv]*
+//! *Compiler support: [requires `rustc` 1.50+][msrv]*
 //!
 //! [msrv]: #supported-rust-versions
 //!
@@ -60,9 +60,11 @@
 //!   **Requires "std"**.
 //! - `json`: Enables `fmt` support for JSON output. In JSON output, the ANSI
 //!   feature does nothing. **Requires "fmt" and "std"**.
-//! - [`local-time`]: Enables local time formatting when using the [`time`
+//! - `local-time`: Enables local time formatting when using the [`time`
 //!   crate]'s timestamp formatters with the `fmt` subscriber.
 //!
+//! [`registry`]: mod@registry
+//!
 //! ### Optional Dependencies
 //!
 //! - [`tracing-log`]: Enables better formatting for events emitted by `log`
@@ -80,7 +82,7 @@
 //! used without requiring the Rust standard library, although some features are
 //! disabled. Although most of the APIs provided by `tracing-subscriber`, such
 //! as [`fmt`] and [`EnvFilter`], require the standard library, some
-//! functionality, such as the [`Subscriber`] trait, can still be used in
+//! functionality, such as the [`Layer`] trait, can still be used in
 //! `no_std` environments.
 //!
 //! The dependency on the standard library is controlled by two crate feature
@@ -102,10 +104,41 @@
 //! tracing-subscriber = { version = "0.3", default-features = false, features = ["alloc"] }
 //! ```
 //!
+//! ### Unstable Features
+//!
+//! These feature flags enable **unstable** features. The public API may break in 0.1.x
+//! releases. To enable these features, the `--cfg tracing_unstable` must be passed to
+//! `rustc` when compiling.
+//!
+//! The following unstable feature flags are currently available:
+//!
+//! * `valuable`: Enables support for serializing values recorded using the
+//!   [`valuable`] crate as structured JSON in the [`format::Json`] formatter.
+//!
+//! #### Enabling Unstable Features
+//!
+//! The easiest way to set the `tracing_unstable` cfg is to use the `RUSTFLAGS`
+//! env variable when running `cargo` commands:
+//!
+//! ```shell
+//! RUSTFLAGS="--cfg tracing_unstable" cargo build
+//! ```
+//! Alternatively, the following can be added to the `.cargo/config` file in a
+//! project to automatically enable the cfg flag for that project:
+//!
+//! ```toml
+//! [build]
+//! rustflags = ["--cfg", "tracing_unstable"]
+//! ```
+//!
+//! [feature flags]: https://doc.rust-lang.org/cargo/reference/manifest.html#the-features-section
+//! [`valuable`]: https://crates.io/crates/valuable
+//! [`format::Json`]: crate::fmt::format::Json
+//!
 //! ## Supported Rust Versions
 //!
 //! Tracing is built against the latest stable release. The minimum supported
-//! version is 1.42. The current Tracing version is not guaranteed to build on
+//! version is 1.50. The current Tracing version is not guaranteed to build on
 //! Rust versions earlier than the minimum supported version.
 //!
 //! Tracing follows the same compiler support policies as the rest of the Tokio
@@ -116,17 +149,18 @@
 //! supported compiler version is not considered a semver breaking change as
 //! long as doing so complies with this policy.
 //!
-//! [`tracing`]: https://docs.rs/tracing/latest/tracing/
-//! [`Subscriber`]: https://docs.rs/tracing-core/latest/tracing_core/subscriber/trait.Subscriber.html
-//! [`EnvFilter`]: filter/struct.EnvFilter.html
-//! [`fmt`]: fmt/index.html
+//! [`Subscriber`]: tracing_core::subscriber::Subscriber
+//! [`tracing`]: https://docs.rs/tracing/latest/tracing
+//! [`EnvFilter`]: filter::EnvFilter
+//! [`fmt`]: mod@fmt
 //! [`tracing-log`]: https://crates.io/crates/tracing-log
 //! [`smallvec`]: https://crates.io/crates/smallvec
 //! [`env_logger` crate]: https://crates.io/crates/env_logger
 //! [`parking_lot`]: https://crates.io/crates/parking_lot
 //! [`time` crate]: https://crates.io/crates/time
-//! [`liballoc`]: https://doc.rust-lang.org/alloc/index.html
-#![doc(html_root_url = "https://docs.rs/tracing-subscriber/0.3.1")]
+//! [`libstd`]: std
+//! [`liballoc`]: alloc
+#![doc(html_root_url = "https://docs.rs/tracing-subscriber/0.3.15")]
 #![doc(
     html_logo_url = "https://raw.githubusercontent.com/tokio-rs/tracing/master/assets/logo-type.png",
     issue_tracker_base_url = "https://github.com/tokio-rs/tracing/issues/"
diff --git a/vendor/tracing-subscriber-0.3.3/src/macros.rs b/vendor/tracing-subscriber/src/macros.rs
index 81351132f..81351132f 100644
--- a/vendor/tracing-subscriber-0.3.3/src/macros.rs
+++ b/vendor/tracing-subscriber/src/macros.rs
diff --git a/vendor/tracing-subscriber-0.3.3/src/prelude.rs b/vendor/tracing-subscriber/src/prelude.rs
index c2230907b..c2230907b 100644
--- a/vendor/tracing-subscriber-0.3.3/src/prelude.rs
+++ b/vendor/tracing-subscriber/src/prelude.rs
diff --git a/vendor/tracing-subscriber-0.3.3/src/registry/extensions.rs b/vendor/tracing-subscriber/src/registry/extensions.rs
index 899e1549f..ff76fb599 100644
--- a/vendor/tracing-subscriber-0.3.3/src/registry/extensions.rs
+++ b/vendor/tracing-subscriber/src/registry/extensions.rs
@@ -78,7 +78,7 @@ impl<'a> ExtensionsMut<'a> {
     /// should be able to reuse timestamp _x_.
     ///
     /// Therefore, extensions should generally be newtypes, rather than common
-    /// types like [`String`](https://doc.rust-lang.org/std/string/struct.String.html), to avoid accidental
+    /// types like [`String`](std::string::String), to avoid accidental
     /// cross-`Layer` clobbering.
     ///
     /// ## Panics
diff --git a/vendor/tracing-subscriber-0.3.3/src/registry/mod.rs b/vendor/tracing-subscriber/src/registry/mod.rs
index f3b77b6a9..38af53e8a 100644
--- a/vendor/tracing-subscriber-0.3.3/src/registry/mod.rs
+++ b/vendor/tracing-subscriber/src/registry/mod.rs
@@ -55,8 +55,7 @@
 //! require the root subscriber to be a registry.
 //!
 //! [`Layer`]: crate::layer::Layer
-//! [`Subscriber`]:
-//!     https://docs.rs/tracing-core/latest/tracing_core/subscriber/trait.Subscriber.html
+//! [`Subscriber`]: tracing_core::Subscriber
 //! [ctx]: crate::layer::Context
 //! [lookup]: crate::layer::Context::span()
 use tracing_core::{field::FieldSet, span::Id, Metadata};
@@ -87,9 +86,9 @@ feature! {
 /// implement this trait; if they do, any [`Layer`]s wrapping them can look up
 /// metadata via the [`Context`] type's [`span()`] method.
 ///
-/// [`Layer`]: ../layer/trait.Layer.html
-/// [`Context`]: ../layer/struct.Context.html
-/// [`span()`]: ../layer/struct.Context.html#method.span
+/// [`Layer`]: super::layer::Layer
+/// [`Context`]: super::layer::Context
+/// [`span()`]: super::layer::Context::span
 pub trait LookupSpan<'a> {
     /// The type of span data stored in this registry.
     type Data: SpanData<'a>;
@@ -104,7 +103,6 @@ pub trait LookupSpan<'a> {
     /// capable of performing more sophisiticated queries.
     /// </pre>
     ///
-    /// [`SpanData`]: trait.SpanData.html
     fn span_data(&'a self, id: &Id) -> Option<Self::Data>;
 
     /// Returns a [`SpanRef`] for the span with the given `Id`, if it exists.
@@ -116,9 +114,7 @@ pub trait LookupSpan<'a> {
     /// rather than the [`span_data`] method; while _implementors_ of this trait
     /// should only implement `span_data`.
     ///
-    /// [`SpanRef`]: struct.SpanRef.html
-    /// [`SpanData`]: trait.SpanData.html
-    /// [`span_data`]: #method.span_data
+    /// [`span_data`]: LookupSpan::span_data()
     fn span(&'a self, id: &Id) -> Option<SpanRef<'_, Self>>
     where
         Self: Sized,
@@ -208,8 +204,8 @@ pub trait SpanData<'a> {
 /// provides additional methods for querying the registry based on values from
 /// the span.
 ///
-/// [span data]: trait.SpanData.html
-/// [registry]: trait.LookupSpan.html
+/// [span data]: SpanData
+/// [registry]: LookupSpan
 #[derive(Debug)]
 pub struct SpanRef<'a, R: LookupSpan<'a>> {
     registry: &'a R,
@@ -360,7 +356,7 @@ where
 
     /// Returns a list of [fields] defined by the span.
     ///
-    /// [fields]: https://docs.rs/tracing-core/latest/tracing_core/field/index.html
+    /// [fields]: tracing_core::field
     pub fn fields(&self) -> &FieldSet {
         self.data.metadata().fields()
     }
diff --git a/vendor/tracing-subscriber-0.3.3/src/registry/sharded.rs b/vendor/tracing-subscriber/src/registry/sharded.rs
index a6311cb71..797899767 100644
--- a/vendor/tracing-subscriber-0.3.3/src/registry/sharded.rs
+++ b/vendor/tracing-subscriber/src/registry/sharded.rs
@@ -75,16 +75,16 @@ use tracing_core::{
 /// the distributed tracing system. These IDs can be associated with
 /// `tracing` spans using [fields] and/or [stored span data].
 ///
-/// [span IDs]: https://docs.rs/tracing-core/latest/tracing_core/span/struct.Id.html
-/// [slab]: https://docs.rs/crate/sharded-slab/
+/// [span IDs]: tracing_core::span::Id
+/// [slab]: sharded_slab
 /// [`Layer`]: crate::Layer
 /// [added]: crate::layer::Layer#composing-layers
 /// [extensions]: super::Extensions
 /// [closed]: https://docs.rs/tracing/latest/tracing/span/index.html#closing-spans
-/// [considered closed]: https://docs.rs/tracing-core/latest/tracing_core/subscriber/trait.Subscriber.html#method.try_close
+/// [considered closed]: tracing_core::subscriber::Subscriber::try_close()
 /// [`Span`]: https://docs.rs/tracing/latest/tracing/span/struct.Span.html
 /// [ot]: https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/trace/api.md#spancontext
-/// [fields]: https://docs.rs/tracing-core/latest/tracing-core/field/index.html
+/// [fields]: tracing_core::field
 /// [stored span data]: crate::registry::SpanData::extensions_mut
 #[cfg(feature = "registry")]
 #[cfg_attr(docsrs, doc(cfg(all(feature = "registry", feature = "std"))))]
@@ -102,9 +102,8 @@ pub struct Registry {
 /// [`Layer`s], such as formatted fields, metrics, or distributed traces should
 /// be stored in the [extensions] typemap.
 ///
-/// [`Registry`]: struct.Registry.html
-/// [`Layer`s]: ../layer/trait.Layer.html
-/// [extensions]: struct.Extensions.html
+/// [`Layer`s]: crate::layer::Layer
+/// [extensions]: Extensions
 #[cfg(feature = "registry")]
 #[cfg_attr(docsrs, doc(cfg(all(feature = "registry", feature = "std"))))]
 #[derive(Debug)]
@@ -115,10 +114,11 @@ pub struct Data<'a> {
 
 /// Stored data associated with a span.
 ///
-/// This type is pooled using `sharded_slab::Pool`; when a span is dropped, the
-/// `DataInner` entry at that span's slab index is cleared in place and reused
-/// by a future span. Thus, the `Default` and `sharded_slab::Clear`
-/// implementations for this type are load-bearing.
+/// This type is pooled using [`sharded_slab::Pool`]; when a span is
+/// dropped, the `DataInner` entry at that span's slab index is cleared
+/// in place and reused by a future span. Thus, the `Default` and
+/// [`sharded_slab::Clear`] implementations for this type are
+/// load-bearing.
 #[derive(Debug)]
 struct DataInner {
     filter_map: FilterMap,
@@ -173,7 +173,6 @@ fn id_to_idx(id: &Id) -> usize {
 ///    greater than 0, `CloseGuard` decrements the counter by one and
 ///    _does not_ remove the span from the [`Registry`].
 ///
-/// [`Registry`]: ./struct.Registry.html
 pub(crate) struct CloseGuard<'a> {
     id: Id,
     registry: &'a Registry,
@@ -189,7 +188,6 @@ impl Registry {
     /// processed an `on_close` notification via the `CLOSE_COUNT` thread-local.
     /// For additional details, see [`CloseGuard`].
     ///
-    /// [`CloseGuard`]: ./struct.CloseGuard.html
     pub(crate) fn start_close(&self, id: Id) -> CloseGuard<'_> {
         CLOSE_COUNT.with(|count| {
             let c = count.get();
@@ -216,7 +214,6 @@ thread_local! {
     /// track how many layers have processed the close.
     /// For additional details, see [`CloseGuard`].
     ///
-    /// [`CloseGuard`]: ./struct.CloseGuard.html
     static CLOSE_COUNT: Cell<usize> = Cell::new(0);
 }
 
@@ -278,6 +275,13 @@ impl Subscriber for Registry {
 
     fn record_follows_from(&self, _span: &span::Id, _follows: &span::Id) {}
 
+    fn event_enabled(&self, _event: &Event<'_>) -> bool {
+        if self.has_per_layer_filters() {
+            return FilterState::event_enabled();
+        }
+        true
+    }
+
     /// This is intentionally not implemented, as recording events
     /// is the responsibility of layers atop of this registry.
     fn event(&self, _: &Event<'_>) {}
@@ -380,7 +384,7 @@ impl<'a> LookupSpan<'a> for Registry {
 // === impl CloseGuard ===
 
 impl<'a> CloseGuard<'a> {
-    pub(crate) fn is_closing(&mut self) {
+    pub(crate) fn set_closing(&mut self) {
         self.is_closing = true;
     }
 }
diff --git a/vendor/tracing-subscriber-0.3.3/src/registry/stack.rs b/vendor/tracing-subscriber/src/registry/stack.rs
index 4a3f7e59d..4a3f7e59d 100644
--- a/vendor/tracing-subscriber-0.3.3/src/registry/stack.rs
+++ b/vendor/tracing-subscriber/src/registry/stack.rs
diff --git a/vendor/tracing-subscriber-0.3.3/src/sync.rs b/vendor/tracing-subscriber/src/sync.rs
index ec42b834a..ec42b834a 100644
--- a/vendor/tracing-subscriber-0.3.3/src/sync.rs
+++ b/vendor/tracing-subscriber/src/sync.rs
diff --git a/vendor/tracing-subscriber-0.3.3/src/util.rs b/vendor/tracing-subscriber/src/util.rs
index 1c98aa4d2..1c98aa4d2 100644
--- a/vendor/tracing-subscriber-0.3.3/src/util.rs
+++ b/vendor/tracing-subscriber/src/util.rs