Fixed a small problem in the lexer for things like ?.5

mozilla · Oct 17, 2024 · b1d727e · b1d727e
1 parent d924f24
commit b1d727e
Show file tree

Hide file tree

Showing 2 changed files with 13 additions and 4 deletions.
diff --git a/rhino/src/main/java/org/mozilla/javascript/TokenStream.java b/rhino/src/main/java/org/mozilla/javascript/TokenStream.java
@@ -1148,10 +1148,14 @@ && peekChar() == '!'
                     return Token.COMMA;
                 case '?':
                     if (parser.compilerEnv.getLanguageVersion() >= Context.VERSION_ES6) {
-                        if (matchChar('.')) {
-                            return Token.QUESTION_DOT;
-                        }
-                        if (matchChar('?')) {
+                        if (peekChar() == '.') {
+                            // ?.digit is to be treated as ? .num
+                            getChar();
+                            if (!isDigit(peekChar())) {
+                                return Token.QUESTION_DOT;   
+                            }
+                            ungetChar('.');
+                        } else if (matchChar('?')) {
                             return Token.NULLISH_COALESCING;
                         }
                     }

diff --git a/tests/src/test/java/org/mozilla/javascript/tests/OptionalChainingOperatorTest.java b/tests/src/test/java/org/mozilla/javascript/tests/OptionalChainingOperatorTest.java
@@ -100,4 +100,9 @@ public void shortCircuits() {
 	    Utils.assertWithAllOptimizationLevelsES6(Undefined.instance, "a = undefined; a?.b.c");
 	    Utils.assertWithAllOptimizationLevelsES6(Undefined.instance, "a = {}; a.b?.c.d.e");
     }
+
+    @Test
+    public void optionalChainingOperatorFollowedByDigitsIsAHook() {
+        Utils.assertWithAllOptimizationLevelsES6(0.5, "true ?.5 : false");
+    }
 }