#239 #240 Rust: Add raw identifier lexing

Ekopalypse · nyamatongwe · commit 89475248f8b5 · 2024-04-16T12:04:55.000+10:00
diff --git a/doc/LexillaHistory.html b/doc/LexillaHistory.html
@@ -633,6 +633,11 @@ <h3>
 	Ruby: Allow modifier if, unless, while and until after heredoc delimiter.
 	<a href="https://github.com/ScintillaOrg/lexilla/issues/236">Issue #236</a>.
 	</li>
+	<li>
+	Rust: Recognize raw identifiers.
+	<a href="https://github.com/ScintillaOrg/lexilla/issues/239">Issue #239</a>,
+	<a href="https://github.com/ScintillaOrg/lexilla/pull/240">Pull request #240</a>.
+	</li>
     </ul>
     <h3>
        <a href="https://www.scintilla.org/lexilla531.zip">Release 5.3.1</a>
diff --git a/lexers/LexRust.cxx b/lexers/LexRust.cxx
@@ -207,6 +207,24 @@ static void GrabString(char* s, Accessor& styler, Sci_Position start, Sci_Positi
 	s[len] = '\0';
 }
 
+static void ScanRawIdentifier(Accessor& styler, Sci_Position& pos) {
+	Sci_Position start = pos;
+	while (IsIdentifierContinue(styler.SafeGetCharAt(pos, '\0')))
+		pos++;
+
+	char s[MAX_RUST_IDENT_CHARS + 1];
+	Sci_Position len = pos - start;
+	len = len > MAX_RUST_IDENT_CHARS ? MAX_RUST_IDENT_CHARS : len;
+	GrabString(s, styler, start, len);
+	// restricted values https://doc.rust-lang.org/reference/identifiers.html#raw-identifiers
+	if (strcmp(s, "crate") != 0 && strcmp(s, "self") != 0 &&
+		strcmp(s, "super") != 0 && strcmp(s, "Self") != 0) {
+		styler.ColourTo(pos - 1, SCE_RUST_IDENTIFIER);
+	} else {
+		styler.ColourTo(pos - 1, SCE_RUST_LEXERROR);
+	}
+}
+
 static void ScanIdentifier(Accessor& styler, Sci_Position& pos, WordList *keywords) {
 	Sci_Position start = pos;
 	while (IsIdentifierContinue(styler.SafeGetCharAt(pos, '\0')))
@@ -704,6 +722,9 @@ void SCI_METHOD LexerRust::Lex(Sci_PositionU startPos, Sci_Position length, int
 			ScanWhitespace(styler, pos, max);
 		} else if (c == '/' && (n == '/' || n == '*')) {
 			ScanComments(styler, pos, max);
+		} else if (c == 'r' && (n == '#' && IsIdentifierStart(n2))) {
+			pos += 2;
+			ScanRawIdentifier(styler, pos);
 		} else if (c == 'r' && (n == '#' || n == '"')) {
 			ScanRawString(styler, pos, max, false);
 		} else if (c == 'b' && n == 'r' && (n2 == '#' || n2 == '"')) {
diff --git a/test/examples/rust/Issue239.rs b/test/examples/rust/Issue239.rs
@@ -0,0 +1,4 @@
+fn main() {
+    let r#true = false;
+    println!("{}", r#true);
+}
diff --git a/test/examples/rust/Issue239.rs.folded b/test/examples/rust/Issue239.rs.folded
@@ -0,0 +1,4 @@
+ 2 400 401 + fn main() {
+ 0 401 401 |     let r#true = false;
+ 0 401 401 |     println!("{}", r#true);
+ 0 401 400 | }
diff --git a/test/examples/rust/Issue239.rs.styled b/test/examples/rust/Issue239.rs.styled
@@ -0,0 +1,4 @@
+{6}fn{0} {17}main{16}(){0} {16}{{0}
+    {6}let{0} {17}r#true{0} {16}={0} {6}false{16};{0}
+    {19}println!{16}({13}"{}"{16},{0} {17}r#true{16});{0}
+{16}}
