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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
commit36d22d82aa202bb199967e9512281e9a53db42c9 (patch)
tree105e8c98ddea1c1e4784a60a5a6410fa416be2de /third_party/rust/quote/src/spanned.rs
parentInitial commit. (diff)
downloadfirefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.tar.xz
firefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.zip
Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'third_party/rust/quote/src/spanned.rs')
-rw-r--r--third_party/rust/quote/src/spanned.rs43
1 files changed, 43 insertions, 0 deletions
diff --git a/third_party/rust/quote/src/spanned.rs b/third_party/rust/quote/src/spanned.rs
new file mode 100644
index 0000000000..f64c8f5dfe
--- /dev/null
+++ b/third_party/rust/quote/src/spanned.rs
@@ -0,0 +1,43 @@
+use crate::ToTokens;
+use proc_macro2::{Span, TokenStream};
+
+pub trait Spanned {
+ fn __span(&self) -> Span;
+}
+
+impl Spanned for Span {
+ fn __span(&self) -> Span {
+ *self
+ }
+}
+
+impl<T: ?Sized + ToTokens> Spanned for T {
+ fn __span(&self) -> Span {
+ join_spans(self.into_token_stream())
+ }
+}
+
+fn join_spans(tokens: TokenStream) -> Span {
+ #[cfg(not(needs_invalid_span_workaround))]
+ let mut iter = tokens.into_iter().map(|tt| tt.span());
+
+ #[cfg(needs_invalid_span_workaround)]
+ let mut iter = tokens.into_iter().filter_map(|tt| {
+ let span = tt.span();
+ let debug = format!("{:?}", span);
+ if debug.ends_with("bytes(0..0)") {
+ None
+ } else {
+ Some(span)
+ }
+ });
+
+ let first = match iter.next() {
+ Some(span) => span,
+ None => return Span::call_site(),
+ };
+
+ iter.fold(None, |_prev, next| Some(next))
+ .and_then(|last| first.join(last))
+ .unwrap_or(first)
+}