For in-of declaration should only throw error after initialization. (#3541)

This patch fixes the error introduced in #3513.

JerryScript-DCO-1.0-Signed-off-by: Robert Fancsik frobert@inf.u-szeged.hu

jerry-core/parser/js/js-parser-statm.c

@@ -1168,11 +1168,6 @@ parser_parse_for_statement_start (parser_context_t *context_p) /**< context */
         || context_p->token.type == LEXER_KEYW_LET
         || context_p->token.type == LEXER_KEYW_CONST)
     {
-      if (context_p->status_flags & PARSER_IS_STRICT)
-      {
-        parser_raise_error (context_p, PARSER_ERR_FOR_IN_OF_DECLARATION);
-      }
-
       token_type = context_p->token.type;
       has_context = (context_p->token.type != LEXER_KEYW_VAR);
       scanner_get_location (&start_location, context_p);
@@ -1311,6 +1306,12 @@ parser_parse_for_statement_start (parser_context_t *context_p) /**< context */
 
         if (context_p->token.type == LEXER_ASSIGN)
         {
+#if ENABLED (JERRY_ES2015)
+          if (context_p->status_flags & PARSER_IS_STRICT)
+          {
+            parser_raise_error (context_p, PARSER_ERR_FOR_IN_OF_DECLARATION);
+          }
+#endif /* ENABLED (JERRY_ES2015) */
           parser_branch_t branch;
 
           /* Initialiser is never executed. */

tests/jerry/es2015/forin-header-strict.js

@@ -27,3 +27,35 @@ try {
 } catch (e) {
   assert(e instanceof SyntaxError);
 }
+
+var reached = false;
+
+for (var i in {}) {
+  reached = true;
+}
+assert(!reached);
+
+for (var i of []) {
+  reached = true;
+}
+assert(!reached);
+
+for (let i in {}) {
+  reached = true;
+}
+assert(!reached);
+
+for (let i of []) {
+  reached = true;
+}
+assert(!reached);
+
+for (const i in {}) {
+  reached = true;
+}
+assert(!reached);
+
+for (const i of []) {
+  reached = true;
+}
+assert(!reached);