Array.prototype.{every, filter, find, findIndex, forEach, map, some}: Use fresh primitive wrapper f…

test/mjsunit/array-iteration.js

Index: test/mjsunit/array-iteration.js
diff --git a/test/mjsunit/array-iteration.js b/test/mjsunit/array-iteration.js
index d11f984bee43be0a7e54794c52d2e05421bd74bb..7186194b765798c211b6b07d02d2031b121b1949 100644
--- a/test/mjsunit/array-iteration.js
+++ b/test/mjsunit/array-iteration.js
@@ -68,6 +68,23 @@
   assertEquals(3, count);
   for (var i in a) assertEquals(2, a[i]);
 
+  // When evaluating 'this', primitive values should be coerced to an object.

[wingo, 2014/09/23 18:39:01]

previous comment was more correct -- the wrapper happens when determining the
receiver for the function call, not when evaluating this within the function.

[Diego Pino, 2014/09/24 10:13:01]

Acknowledged.

+  // See ECMA-262, Annex C.
+  a = [];
+  [1, 2].filter(function() { a.push(this) }, "");
+  assertTrue(a[0] !== a[1]);
+
+  // When evaluating 'this', non-primitive values are not coerced to an object.
+  a = [];
+  [1, 2].filter(function() { a.push(this) }, {});
+  assertFalse(a[0] !== a[1]);
+
+  // In strict mode, when evaluating 'this', primitive values should not be
+  // coerced to an object.
+  a = [];
+  [1, 2].filter(function() { 'use strict'; a.push(this); }, "");

[wingo, 2014/09/23 18:39:01]

great test.

+  assertTrue(a[0] === "" && a[0] === a[1]);
+
 })();
 
 
@@ -109,6 +126,23 @@
   a.forEach(function(n) { count++; });
   assertEquals(1, count);
 
+  // When evaluating 'this', primitive values should be coerced to an object.
+  // See ECMA-262, Annex C.
+  a = [];
+  [1, 2].forEach(function() { a.push(this) }, "");
+  assertTrue(a[0] !== a[1]);
+
+  // When evaluating 'this', non-primitive values are not coerced to an object.
+  a = [];
+  [1, 2].forEach(function() { a.push(this) }, {});
+  assertFalse(a[0] !== a[1]);
+
+  // In strict mode, when evaluating 'this', primitive values should not be
+  // coerced to an object.
+  a = [];
+  [1, 2].forEach(function() { 'use strict'; a.push(this); }, "");
+  assertTrue(a[0] === "" && a[0] === a[1]);
+
 })();
 
 
@@ -149,6 +183,23 @@
   assertTrue(a.every(function(n) { count++; return n == 2; }));
   assertEquals(2, count);
 
+  // When evaluating 'this', primitive values should be coerced to an object.
+  // See ECMA-262, Annex C.
+  a = [];
+  [1, 2].every(function() { a.push(this); return true; }, "");
+  assertTrue(a[0] !== a[1]);
+
+  // When evaluating 'this', non-primitive values are not coerced to an object.
+  a = [];
+  [1, 2].every(function() { a.push(this); return true; }, {});
+  assertFalse(a[0] !== a[1]);
+
+  // In strict mode, when evaluating 'this', primitive values should not be
+  // coerced to an object.
+  a = [];
+  [1, 2].every(function() { 'use strict'; a.push(this); return true; }, "");
+  assertTrue(a[0] === "" && a[0] === a[1]);
+
 })();
 
 //
@@ -186,6 +237,23 @@
   a = a.map(function(n) { return 2*n; });
   for (var i in a) assertEquals(4, a[i]);
 
+  // When evaluating 'this', primitive values should be coerced to an object.
+  // See ECMA-262, Annex C.
+  a = [];
+  [1, 2].map(function() { a.push(this) }, "");
+  assertTrue(a[0] !== a[1]);
+
+  // When evaluating 'this', non-primitive values are not coerced to an object.
+  a = [];
+  [1, 2].map(function() { a.push(this) }, {});
+  assertFalse(a[0] !== a[1]);
+
+  // In strict mode, when evaluating 'this', primitive values should not be
+  // coerced to an object.
+  a = [];
+  [1, 2].map(function() { 'use strict'; a.push(this); }, "");
+  assertTrue(a[0] === "" && a[0] === a[1]);
+
 })();
 
 //
@@ -224,4 +292,21 @@
   assertTrue(a.some(function(n) { count++; return n == 2; }));
   assertEquals(2, count);
 
+  // When evaluating 'this', primitive values should be coerced to an object.
+  // See ECMA-262, Annex C.
+  a = [];
+  [1, 2].some(function() { a.push(this) }, "");
+  assertTrue(a[0] !== a[1]);
+
+  // When evaluating 'this', non-primitive values are not coerced to an object.
+  a = [];
+  [1, 2].some(function() { a.push(this) }, {});
+  assertFalse(a[0] !== a[1]);
+
+  // In strict mode, when evaluating 'this', primitive values should not be
+  // coerced to an object.
+  a = [];
+  [1, 2].some(function() { 'use strict'; a.push(this); }, "");
+  assertTrue(a[0] === "" && a[0] === a[1]);
+
 })();