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-rw-r--r--vendor/quote/src/spanned.rs50
1 files changed, 50 insertions, 0 deletions
diff --git a/vendor/quote/src/spanned.rs b/vendor/quote/src/spanned.rs
new file mode 100644
index 0000000..6eba644
--- /dev/null
+++ b/vendor/quote/src/spanned.rs
@@ -0,0 +1,50 @@
+use crate::ToTokens;
+use proc_macro2::extra::DelimSpan;
+use proc_macro2::{Span, TokenStream};
+
+// Not public API other than via the syn crate. Use syn::spanned::Spanned.
+pub trait Spanned: private::Sealed {
+ fn __span(&self) -> Span;
+}
+
+impl Spanned for Span {
+ fn __span(&self) -> Span {
+ *self
+ }
+}
+
+impl Spanned for DelimSpan {
+ fn __span(&self) -> Span {
+ self.join()
+ }
+}
+
+impl<T: ?Sized + ToTokens> Spanned for T {
+ fn __span(&self) -> Span {
+ join_spans(self.into_token_stream())
+ }
+}
+
+fn join_spans(tokens: TokenStream) -> Span {
+ let mut iter = tokens.into_iter().map(|tt| tt.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)
+}
+
+mod private {
+ use crate::ToTokens;
+ use proc_macro2::extra::DelimSpan;
+ use proc_macro2::Span;
+
+ pub trait Sealed {}
+ impl Sealed for Span {}
+ impl Sealed for DelimSpan {}
+ impl<T: ?Sized + ToTokens> Sealed for T {}
+}