Merging upstream version 1.73.0+dfsg1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

3 files changed, 16 insertions, 8 deletions

diff --git a/compiler/rustc_lexer/src/cursor.rs b/compiler/rustc_lexer/src/cursor.rs
index eceef5980..aba7f9548 100644
--- a/compiler/rustc_lexer/src/cursor.rs
+++ b/compiler/rustc_lexer/src/cursor.rs
@@ -24,6 +24,10 @@ impl<'a> Cursor<'a> {
         }
     }
 
+    pub fn as_str(&self) -> &'a str {
+        self.chars.as_str()
+    }
+
     /// Returns the last eaten symbol (or `'\0'` in release builds).
     /// (For debug assertions only.)
     pub(crate) fn prev(&self) -> char {
diff --git a/compiler/rustc_lexer/src/lib.rs b/compiler/rustc_lexer/src/lib.rs
index 29335a8c0..43dfd34a6 100644
--- a/compiler/rustc_lexer/src/lib.rs
+++ b/compiler/rustc_lexer/src/lib.rs
@@ -34,6 +34,7 @@ pub use crate::cursor::Cursor;
 use self::LiteralKind::*;
 use self::TokenKind::*;
 use crate::cursor::EOF_CHAR;
+use unicode_properties::UnicodeEmoji;
 
 /// Parsed token.
 /// It doesn't contain information about data that has been parsed,
@@ -367,6 +368,13 @@ impl Cursor<'_> {
                 Some(|terminated| Byte { terminated }),
             ),
 
+            // c-string literal, raw c-string literal or identifier.
+            'c' => self.c_or_byte_string(
+                |terminated| CStr { terminated },
+                |n_hashes| RawCStr { n_hashes },
+                None,
+            ),
+
             // Identifier (this should be checked after other variant that can
             // start as identifier).
             c if is_id_start(c) => self.ident_or_unknown_prefix(),
@@ -421,9 +429,7 @@ impl Cursor<'_> {
                 Literal { kind, suffix_start }
             }
             // Identifier starting with an emoji. Only lexed for graceful error recovery.
-            c if !c.is_ascii() && unic_emoji_char::is_emoji(c) => {
-                self.fake_ident_or_unknown_prefix()
-            }
+            c if !c.is_ascii() && c.is_emoji_char() => self.fake_ident_or_unknown_prefix(),
             _ => Unknown,
         };
         let res = Token::new(token_kind, self.pos_within_token());
@@ -507,9 +513,7 @@ impl Cursor<'_> {
         // we see a prefix here, it is definitely an unknown prefix.
         match self.first() {
             '#' | '"' | '\'' => UnknownPrefix,
-            c if !c.is_ascii() && unic_emoji_char::is_emoji(c) => {
-                self.fake_ident_or_unknown_prefix()
-            }
+            c if !c.is_ascii() && c.is_emoji_char() => self.fake_ident_or_unknown_prefix(),
             _ => Ident,
         }
     }
@@ -518,7 +522,7 @@ impl Cursor<'_> {
         // Start is already eaten, eat the rest of identifier.
         self.eat_while(|c| {
             unicode_xid::UnicodeXID::is_xid_continue(c)
-                || (!c.is_ascii() && unic_emoji_char::is_emoji(c))
+                || (!c.is_ascii() && c.is_emoji_char())
                 || c == '\u{200d}'
         });
         // Known prefixes must have been handled earlier. So if
diff --git a/compiler/rustc_lexer/src/unescape.rs b/compiler/rustc_lexer/src/unescape.rs
index c9ad54d8d..717b042fb 100644
--- a/compiler/rustc_lexer/src/unescape.rs
+++ b/compiler/rustc_lexer/src/unescape.rs
@@ -372,7 +372,7 @@ where
         callback(start..end, EscapeError::MultipleSkippedLinesWarning);
     }
     let tail = &tail[first_non_space..];
-    if let Some(c) = tail.chars().nth(0) {
+    if let Some(c) = tail.chars().next() {
         if c.is_whitespace() {
             // For error reporting, we would like the span to contain the character that was not
             // skipped. The +1 is necessary to account for the leading \ that started the escape.