1 files changed, 95 insertions, 0 deletions
diff --git a/third_party/rust/time-macros/src/offset.rs b/third_party/rust/time-macros/src/offset.rs
new file mode 100644
index 0000000000..c2099073f8
--- /dev/null
+++ b/third_party/rust/time-macros/src/offset.rs
@@ -0,0 +1,95 @@
+use std::iter::Peekable;
+
+use proc_macro::{token_stream, Span, TokenTree};
+
+use crate::helpers::{consume_any_ident, consume_number, consume_punct};
+use crate::to_tokens::ToTokenTree;
+use crate::Error;
+
+pub(crate) struct Offset {
+    pub(crate) hours: i8,
+    pub(crate) minutes: i8,
+    pub(crate) seconds: i8,
+}
+
+pub(crate) fn parse(chars: &mut Peekable<token_stream::IntoIter>) -> Result<Offset, Error> {
+    if consume_any_ident(&["utc", "UTC"], chars).is_ok() {
+        return Ok(Offset {
+            hours: 0,
+            minutes: 0,
+            seconds: 0,
+        });
+    }
+
+    let sign = if consume_punct('+', chars).is_ok() {
+        1
+    } else if consume_punct('-', chars).is_ok() {
+        -1
+    } else if let Some(tree) = chars.next() {
+        return Err(Error::UnexpectedToken { tree });
+    } else {
+        return Err(Error::MissingComponent {
+            name: "sign",
+            span_start: None,
+            span_end: None,
+        });
+    };
+
+    let (hours_span, hours) = consume_number::<i8>("hour", chars)?;
+    let (mut minutes_span, mut minutes) = (Span::mixed_site(), 0);
+    let (mut seconds_span, mut seconds) = (Span::mixed_site(), 0);
+
+    if consume_punct(':', chars).is_ok() {
+        let min = consume_number::<i8>("minute", chars)?;
+        minutes_span = min.0;
+        minutes = min.1;
+
+        if consume_punct(':', chars).is_ok() {
+            let sec = consume_number::<i8>("second", chars)?;
+            seconds_span = sec.0;
+            seconds = sec.1;
+        }
+    }
+
+    if hours >= 24 {
+        Err(Error::InvalidComponent {
+            name: "hour",
+            value: hours.to_string(),
+            span_start: Some(hours_span),
+            span_end: Some(hours_span),
+        })
+    } else if minutes >= 60 {
+        Err(Error::InvalidComponent {
+            name: "minute",
+            value: minutes.to_string(),
+            span_start: Some(minutes_span),
+            span_end: Some(minutes_span),
+        })
+    } else if seconds >= 60 {
+        Err(Error::InvalidComponent {
+            name: "second",
+            value: seconds.to_string(),
+            span_start: Some(seconds_span),
+            span_end: Some(seconds_span),
+        })
+    } else {
+        Ok(Offset {
+            hours: sign * hours,
+            minutes: sign * minutes,
+            seconds: sign * seconds,
+        })
+    }
+}
+
+impl ToTokenTree for Offset {
+    fn into_token_tree(self) -> TokenTree {
+        quote_group! {{
+            const OFFSET: ::time::UtcOffset = ::time::UtcOffset::__from_hms_unchecked(
+                #(self.hours),
+                #(self.minutes),
+                #(self.seconds),
+            );
+            OFFSET
+        }}
+    }
+}