Restrict FunctionDeclarations in Statement position

test/mjsunit/harmony/sloppy-restrictive-block-function.js

+// Copyright 2016 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Flags: --harmony-restrictive-declarations
+
+// ES#sec-functiondeclarations-in-ifstatement-statement-clauses
+// Annex B 3.4 FunctionDeclarations in IfStatement Statement Clauses
+// In sloppy mode, function declarations in if statements act like
+// they have a block around them. Prohibited in strict mode.
+(function() {
+  if (false) function f() { };
+  assertEquals(undefined, f);
+})();
+
+assertThrows(`
+  function() {
+    'use strict';
+    if (true) function foo() {}
+  }
+`, SyntaxError);
+
+// In the spec-compliant mode, legacy features of allowing function
+// declarations as the body of various constructs is disallowed.
+assertThrows(`
+  for (;false;) function f() { };
+`, SyntaxError);
+
+assertThrows(`
+  for (var x in {}) function f() { };
+`, SyntaxError);
+
+assertThrows(`
+  for (x in {}) function f() { };
+`, SyntaxError);
+
+assertThrows(`
+  for (var i = 0; i < 1; i++) function f() { };
+`, SyntaxError);
+
+assertThrows(`
+  for (var x in {a: 1}) function f() { };
+`, SyntaxError);
+
+assertThrows(`
+  for (x in {a: 1}) function f() { };
+`, SyntaxError);
+
+assertThrows(`
+  with ({}) function f() { };
+`, SyntaxError);
+
+assertThrows(`
+  do function foo() {} while (0);
+`, SyntaxError);
+
+assertThrows(`
+  function() {
+    'use strict';
+    for (;false;) function foo() {}
+  }
+`, SyntaxError);
+
+assertThrows(`
+  function() {
+    'use strict';
+    for (var x in {}) function foo() {}
+  }
+`, SyntaxError);
+
+assertThrows(`
+  function() {
+    'use strict';
+    var x;
+    for (x in {}) function foo() {}
+  }
+`, SyntaxError);
+
+assertThrows(`
+  function() {
+    'use strict';
+    do function foo() {} while (0);
+  }
+`, SyntaxError);
+
+// Some contexts always throw for function declarations, even in sloppy mode
+
+assertThrows(`
+  function() {
+    try function foo() {} catch (e) {}
+  }
+`, SyntaxError);
+
+assertThrows(`
+  function() {
+    'use strict';
+    try function foo() {} catch (e) {}
+  }
+`, SyntaxError);