fix(lua): consume escaped short-string newlines

gitnexus/test/unit/parser-loader-abi.test.ts

@@ -193,4 +193,23 @@ describe('parser-loader ABI load-smoke (#1922)', () => {
       expect(tree.rootNode.hasError).toBe(false);
     }
   });
+
+  it('accepts a real newline escaped inside a short string', () => {
+    let grammar: unknown;
+    try {
+      grammar = getLanguageGrammar(SupportedLanguages.Lua);
+    } catch (err) {
+      expect(err).toBeInstanceOf(Error);
+      return;
+    }
+
+    const parser = new Parser();
+    parser.setLanguage(grammar as Parameters<Parser['setLanguage']>[0]);
+    const snippet = String.raw`local value = "line\
+continued"
+`;
+    const tree = parser.parse(snippet);
+    expect(tree.rootNode.type).toBe('chunk');
+    expect(tree.rootNode.hasError).toBe(false);
+  });
 });

gitnexus/vendor/tree-sitter-lua/src/scanner.c

@@ -171,10 +171,20 @@ bool tree_sitter_lua_external_scanner_scan(void *payload, TSLexer *lexer, const
       // consume any character till a short string's end, new line or eof
       do
       {
-        // consume any character after a backslash, unless it's a new line or eof
-        if (consume_if(lexer, '\\') && (lexer->lookahead == '\n' || lexer->eof(lexer)))
+        // A backslash escapes the following character. Lua also permits a
+        // backslash followed by a real newline to continue a short string;
+        // consume that newline so the scanner does not remain stuck at it.
+        if (consume_if(lexer, '\\'))
         {
-          break;
+          if (lexer->lookahead == '\n')
+          {
+            consume(lexer);
+            continue;
+          }
+          if (lexer->eof(lexer))
+          {
+            break;
+          }
         }
 
         consume(lexer);