test

Author: Napalys

javascript/extractor/src/com/semmle/js/parser/RegExpParser.java

@@ -226,18 +226,18 @@ private <T extends RegExpTerm> T finishTerm(T term) {
   private RegExpTerm parseDisjunction() {
     SourceLocation loc = new SourceLocation(pos());
     List<RegExpTerm> disjuncts = new ArrayList<>();
-    disjuncts.add(this.parseIntersection());
+    disjuncts.add(this.parseAlternative());
     while (this.match("|")) {
-        disjuncts.add(this.parseIntersection());
+        disjuncts.add(this.parseAlternative());
     }
     if (disjuncts.size() == 1) return disjuncts.get(0);
     return this.finishTerm(new Disjunction(loc, disjuncts));
-}
+  }
 
   private RegExpTerm parseAlternative() {
     SourceLocation loc = new SourceLocation(pos());
     List<RegExpTerm> elements = new ArrayList<>();
-    while (!this.lookahead(null, "|", "&&", ")")) elements.add(this.parseTerm());
+    while (!this.lookahead(null, "|", ")")) elements.add(this.parseTerm());
     if (elements.size() == 1) return elements.get(0);
     return this.finishTerm(new Sequence(loc, elements));
   }

javascript/extractor/tests/es2024/input/intersection.js

@@ -1 +1,7 @@
-/[[abc]&&[bcd]]/v
+/[[abc]&&[bcd]]/v; // Valid use of intersection operator, matches b or c
+/abc&&bcd/v; //Valid regex, but no intersection operation: Matches the literal string "abc&&bcd"
+/[abc]&&[bcd]/v; // Valid regex, but incorrect intersection operation: 
+                 // - Matches a single character from [abc]
+                 // - Then the literal "&&"
+                 // - Then a single character from [bcd]
+/[abc&&bcd]/v; // Compilation error due to invalid use of intersection operation