[elements] revert overzealous optimzation for fast sloppy arguments delete

test/mjsunit/arguments.js

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 // Flags: --allow-natives-syntax
-

[Igor Sheludko, 2016/04/08 07:36:15]

Spurious change?

 function argc0() {
   return arguments.length;
 }
 
 function argc1(i) {
   return arguments.length;
 }
 
 function argc2(i, j) {
   return arguments.length;
@@ skipping 157 matching lines @@
   // Turn arguments into slow.
   assertTrue(%HasSloppyArgumentsElements(a));
   a[10000] = 1;
   assertTrue(%HasSloppyArgumentsElements(a));
   // Make it fast again by adding values.
   for (var i = 0; i < 1000; i++) {
     a[i] = 1.5;
   }
   assertTrue(%HasSloppyArgumentsElements(a));
 })();
+
+(function testDeleteArguments() {
+  function f() { return arguments };
+  var args = f(1, 2);
+  assertEquals(1, args[0]);
+  assertEquals(2, args[1]);
+  assertEquals(2, args.length);
+
+  delete args[0];
+  assertEquals(undefined, args[0]);
+  assertEquals(2, args[1]);
+  assertEquals(2, args.length);
+
+  delete args[1];
+  assertEquals(undefined, args[0]);
+  assertEquals(undefined, args[1]);
+  assertEquals(2, args.length);
+})();
+
+(function testDeleteFastSloppyArguments() {
+  function f(a) { return arguments };
+  var args = f(1, 2);
+  assertEquals(1, args[0]);
+  assertEquals(2, args[1]);
+  assertEquals(2, args.length);
+
+  delete args[0];
+  assertEquals(undefined, args[0]);
+  assertEquals(2, args[1]);
+  assertEquals(2, args.length);
+
+  delete args[1];
+  assertEquals(undefined, args[0]);
+  assertEquals(undefined, args[1]);
+  assertEquals(2, args.length);
+})();
+
+(function testDeleteSlowSloppyArguments() {
+  var key = 10000;
+  function f(a) {
+    arguments[key] = key;
+    return arguments
+  };
+  var args = f(1, 2);
+  assertEquals(1, args[0]);
+  assertEquals(2, args[1]);
+  assertEquals(key, args[key]);
+  assertEquals(2, args.length);
+
+  delete args[0];
+  assertEquals(undefined, args[0]);
+  assertEquals(2, args[1]);
+  assertEquals(key, args[key]);
+  assertEquals(2, args.length);
+
+  delete args[1];
+  assertEquals(undefined, args[0]);
+  assertEquals(undefined, args[1]);
+  assertEquals(key, args[key]);
+  assertEquals(2, args.length);
+
+  delete args[key];
+  assertEquals(undefined, args[0]);
+  assertEquals(undefined, args[1]);
+  assertEquals(undefined, args[key]);
+  assertEquals(2, args.length);
+})();