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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
commit26a029d407be480d791972afb5975cf62c9360a6 (patch)
treef435a8308119effd964b339f76abb83a57c29483 /third_party/rust/thiserror-impl/src/prop.rs
parentInitial commit. (diff)
downloadfirefox-26a029d407be480d791972afb5975cf62c9360a6.tar.xz
firefox-26a029d407be480d791972afb5975cf62c9360a6.zip
Adding upstream version 124.0.1.upstream/124.0.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'third_party/rust/thiserror-impl/src/prop.rs')
-rw-r--r--third_party/rust/thiserror-impl/src/prop.rs147
1 files changed, 147 insertions, 0 deletions
diff --git a/third_party/rust/thiserror-impl/src/prop.rs b/third_party/rust/thiserror-impl/src/prop.rs
new file mode 100644
index 0000000000..2867cd312a
--- /dev/null
+++ b/third_party/rust/thiserror-impl/src/prop.rs
@@ -0,0 +1,147 @@
+use crate::ast::{Enum, Field, Struct, Variant};
+use crate::span::MemberSpan;
+use proc_macro2::Span;
+use syn::{Member, Type};
+
+impl Struct<'_> {
+ pub(crate) fn from_field(&self) -> Option<&Field> {
+ from_field(&self.fields)
+ }
+
+ pub(crate) fn source_field(&self) -> Option<&Field> {
+ source_field(&self.fields)
+ }
+
+ pub(crate) fn backtrace_field(&self) -> Option<&Field> {
+ backtrace_field(&self.fields)
+ }
+
+ pub(crate) fn distinct_backtrace_field(&self) -> Option<&Field> {
+ let backtrace_field = self.backtrace_field()?;
+ distinct_backtrace_field(backtrace_field, self.from_field())
+ }
+}
+
+impl Enum<'_> {
+ pub(crate) fn has_source(&self) -> bool {
+ self.variants
+ .iter()
+ .any(|variant| variant.source_field().is_some() || variant.attrs.transparent.is_some())
+ }
+
+ pub(crate) fn has_backtrace(&self) -> bool {
+ self.variants
+ .iter()
+ .any(|variant| variant.backtrace_field().is_some())
+ }
+
+ pub(crate) fn has_display(&self) -> bool {
+ self.attrs.display.is_some()
+ || self.attrs.transparent.is_some()
+ || self
+ .variants
+ .iter()
+ .any(|variant| variant.attrs.display.is_some())
+ || self
+ .variants
+ .iter()
+ .all(|variant| variant.attrs.transparent.is_some())
+ }
+}
+
+impl Variant<'_> {
+ pub(crate) fn from_field(&self) -> Option<&Field> {
+ from_field(&self.fields)
+ }
+
+ pub(crate) fn source_field(&self) -> Option<&Field> {
+ source_field(&self.fields)
+ }
+
+ pub(crate) fn backtrace_field(&self) -> Option<&Field> {
+ backtrace_field(&self.fields)
+ }
+
+ pub(crate) fn distinct_backtrace_field(&self) -> Option<&Field> {
+ let backtrace_field = self.backtrace_field()?;
+ distinct_backtrace_field(backtrace_field, self.from_field())
+ }
+}
+
+impl Field<'_> {
+ pub(crate) fn is_backtrace(&self) -> bool {
+ type_is_backtrace(self.ty)
+ }
+
+ pub(crate) fn source_span(&self) -> Span {
+ if let Some(source_attr) = &self.attrs.source {
+ source_attr.path().get_ident().unwrap().span()
+ } else if let Some(from_attr) = &self.attrs.from {
+ from_attr.path().get_ident().unwrap().span()
+ } else {
+ self.member.member_span()
+ }
+ }
+}
+
+fn from_field<'a, 'b>(fields: &'a [Field<'b>]) -> Option<&'a Field<'b>> {
+ for field in fields {
+ if field.attrs.from.is_some() {
+ return Some(field);
+ }
+ }
+ None
+}
+
+fn source_field<'a, 'b>(fields: &'a [Field<'b>]) -> Option<&'a Field<'b>> {
+ for field in fields {
+ if field.attrs.from.is_some() || field.attrs.source.is_some() {
+ return Some(field);
+ }
+ }
+ for field in fields {
+ match &field.member {
+ Member::Named(ident) if ident == "source" => return Some(field),
+ _ => {}
+ }
+ }
+ None
+}
+
+fn backtrace_field<'a, 'b>(fields: &'a [Field<'b>]) -> Option<&'a Field<'b>> {
+ for field in fields {
+ if field.attrs.backtrace.is_some() {
+ return Some(field);
+ }
+ }
+ for field in fields {
+ if field.is_backtrace() {
+ return Some(field);
+ }
+ }
+ None
+}
+
+// The #[backtrace] field, if it is not the same as the #[from] field.
+fn distinct_backtrace_field<'a, 'b>(
+ backtrace_field: &'a Field<'b>,
+ from_field: Option<&Field>,
+) -> Option<&'a Field<'b>> {
+ if from_field.map_or(false, |from_field| {
+ from_field.member == backtrace_field.member
+ }) {
+ None
+ } else {
+ Some(backtrace_field)
+ }
+}
+
+fn type_is_backtrace(ty: &Type) -> bool {
+ let path = match ty {
+ Type::Path(ty) => &ty.path,
+ _ => return false,
+ };
+
+ let last = path.segments.last().unwrap();
+ last.ident == "Backtrace" && last.arguments.is_empty()
+}