Move hash code from hidden string to a private symbol

test/mjsunit/global-hash.js

Index: test/mjsunit/global-hash.js
diff --git a/test/mjsunit/string-search.js b/test/mjsunit/global-hash.js
similarity index 77%
copy from test/mjsunit/string-search.js
copy to test/mjsunit/global-hash.js
index 037725b95eb99ee843dc9e3cb511292e05bedaf4..18ea9f9e7786e865f9d550231dd4be3f1f1d16c1 100644
--- a/test/mjsunit/string-search.js
+++ b/test/mjsunit/global-hash.js
@@ -1,4 +1,4 @@
-// Copyright 2008 the V8 project authors. All rights reserved.
+// Copyright 2015 the V8 project authors. All rights reserved.

[adamk, 2015/05/21 19:11:32]

Please use the short license header for new tests.

[Erik Corry, 2015/05/22 06:20:25]

Done.

 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -25,15 +25,18 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-var str="ABC abc";
-var r = str.search('a');
-assertEquals(r, 4);
+var global = this;
 
-// Test for a lot of different string.
+assertTrue(typeof(global) === "object");  // Global object.
 
-var s = "";
+var s = new Set();
+s.add(global); // Puts a hash code on the global object.
+assertTrue(s.has(global));
 for (var i = 0; i < 100; i++) {
-  s += i;
-  var r = s.search(s);
-  assertEquals(0, r);
+  // Force rehash. Global object is placed according to the hash code that it
+  // gets in the C++ runtime.
+  s.add(i);
 }
+
+// Hopefully still findable using the JS hash code.

[adamk, 2015/05/21 19:11:32]

This test is good, but can you also add a cctest that detaches the proxy and
attaches to a new global to show that the hashcode remains the same across
"navigations".

[Erik Corry, 2015/05/22 06:20:25]

We already had this in test-api.cc, but it added the hash code from C++ so it
didn't test the case where we added from JS.  FIxed to do both.

+assertTrue(s.has(global));