rust: proc-macro2: remove `unicode_ident` dependency

The `proc-macro2` crate depends on the `unicode-ident` crate to determine
whether characters have the XID_Start or XID_Continue properties according
to Unicode Standard Annex #31.

However, we only need ASCII identifiers in the kernel, thus we can
simplify the check and remove completely that dependency.

Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Tested-by: Gary Guo <gary@garyguo.net>
Tested-by: Jesung Yang <y.j3ms.n@gmail.com>
Link: https://patch.msgid.link/20251124151837.2184382-9-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

diff --git a/rust/proc-macro2/fallback.rs b/rust/proc-macro2/fallback.rs
index 9e005d67f7f554974d5814e2de5ba718ae19bd7a..9b43c97df97a1a967c2800eb0c90509e7b7496e0 100644 (file)
--- a/rust/proc-macro2/fallback.rs
+++ b/rust/proc-macro2/fallback.rs
@@ -818,11 +818,11 @@ impl Ident {
 }
 
 pub(crate) fn is_ident_start(c: char) -> bool {
-    c == '_' || unicode_ident::is_xid_start(c)
+    c == '_' || c.is_ascii_alphabetic()
 }
 
 pub(crate) fn is_ident_continue(c: char) -> bool {
-    unicode_ident::is_xid_continue(c)
+    c == '_' || c.is_ascii_alphanumeric()
 }
 
 #[track_caller]