Verify that source string matches serialized code.

test/cctest/test-serialize.cc

Index: test/cctest/test-serialize.cc
diff --git a/test/cctest/test-serialize.cc b/test/cctest/test-serialize.cc
index f025d8f26c152d7952e2043b24a1ea590a13ec32..a68d1be98967aa3fcda6c7f809671cc33a66188b 100644
--- a/test/cctest/test-serialize.cc
+++ b/test/cctest/test-serialize.cc
@@ -32,6 +32,7 @@
 #include "src/v8.h"
 
 #include "src/bootstrapper.h"
+#include "src/compilation-cache.h"
 #include "src/debug.h"
 #include "src/ic-inl.h"
 #include "src/natives.h"
@@ -680,34 +681,36 @@ TEST(SerializeToplevelOnePlusOne) {
   LocalContext context;
   v8::HandleScope scope(CcTest::isolate());
 
-  const char* source1 = "1 + 1";
-  const char* source2 = "1 + 2";  // Use alternate string to verify caching.
+  const char* source = "1 + 1";
 
   Isolate* isolate = CcTest::i_isolate();
-  Handle<String> source1_string = isolate->factory()
-                                      ->NewStringFromUtf8(CStrVector(source1))
-                                      .ToHandleChecked();
+  isolate->compilation_cache()->Disable();
 
-  Handle<String> source2_string = isolate->factory()
-                                      ->NewStringFromUtf8(CStrVector(source2))
-                                      .ToHandleChecked();
+  Handle<String> orig_source = isolate->factory()
+                                   ->NewStringFromUtf8(CStrVector(source))
+                                   .ToHandleChecked();
+  Handle<String> copy_source = isolate->factory()
+                                   ->NewStringFromUtf8(CStrVector(source))
+                                   .ToHandleChecked();
+  CHECK(!orig_source.is_identical_to(copy_source));
+  CHECK(orig_source->Equals(*copy_source));
 
   ScriptData* cache = NULL;
 
   Handle<SharedFunctionInfo> orig =
-      Compiler::CompileScript(source1_string, Handle<String>(), 0, 0, false,
+      Compiler::CompileScript(orig_source, Handle<String>(), 0, 0, false,
                               Handle<Context>(isolate->native_context()), NULL,
                               &cache, PRODUCE_CACHED_DATA, NOT_NATIVES_CODE);
 
   int builtins_count = CountBuiltins();
 
   Handle<SharedFunctionInfo> copy =
-      Compiler::CompileScript(source2_string, Handle<String>(), 0, 0, false,
+      Compiler::CompileScript(copy_source, Handle<String>(), 0, 0, false,
                               Handle<Context>(isolate->native_context()), NULL,
                               &cache, CONSUME_CACHED_DATA, NOT_NATIVES_CODE);
 

[vogelheim, 2014/07/15 13:42:31]

Just for my understanding: Previously, this would check that the 2nd compile
would use the cache (because otherwise we'd get a different result). This CL
would prevent that from working. What this checks now is that caching will work
with a string that's physically different but logically the same?

[Yang, 2014/07/15 13:47:31]

You are right. Currently, if CompileScript was to simply ignore
CONSUME_CACHED_DATA, we wouldn't notice anymore. I have no idea how we would
test that though. Unless we still use a wrong source string in release mode,
where we don't have the source string verification.

   CHECK_NE(*orig, *copy);
-  CHECK(Script::cast(copy->script())->source() == *source2_string);
+  CHECK(Script::cast(copy->script())->source() == *copy_source);
 
   Handle<JSFunction> copy_fun =
       isolate->factory()->NewFunctionFromSharedFunctionInfo(
@@ -728,22 +731,25 @@ TEST(SerializeToplevelInternalizedString) {
   LocalContext context;
   v8::HandleScope scope(CcTest::isolate());
 
-  const char* source1 = "'string1'";
-  const char* source2 = "'string2'";  // Use alternate string to verify caching.
+  const char* source = "'string1'";
 
   Isolate* isolate = CcTest::i_isolate();
-  Handle<String> source1_string = isolate->factory()
-                                      ->NewStringFromUtf8(CStrVector(source1))
-                                      .ToHandleChecked();
+  isolate->compilation_cache()->Disable();
+
+  Handle<String> orig_source = isolate->factory()
+                                   ->NewStringFromUtf8(CStrVector(source))
+                                   .ToHandleChecked();
+  Handle<String> copy_source = isolate->factory()
+                                   ->NewStringFromUtf8(CStrVector(source))
+                                   .ToHandleChecked();
+  CHECK(!orig_source.is_identical_to(copy_source));
+  CHECK(orig_source->Equals(*copy_source));
 
-  Handle<String> source2_string = isolate->factory()
-                                      ->NewStringFromUtf8(CStrVector(source2))
-                                      .ToHandleChecked();
   Handle<JSObject> global(isolate->context()->global_object());
   ScriptData* cache = NULL;
 
   Handle<SharedFunctionInfo> orig =
-      Compiler::CompileScript(source1_string, Handle<String>(), 0, 0, false,
+      Compiler::CompileScript(orig_source, Handle<String>(), 0, 0, false,
                               Handle<Context>(isolate->native_context()), NULL,
                               &cache, PRODUCE_CACHED_DATA, NOT_NATIVES_CODE);
   Handle<JSFunction> orig_fun =
@@ -756,11 +762,11 @@ TEST(SerializeToplevelInternalizedString) {
   int builtins_count = CountBuiltins();
 
   Handle<SharedFunctionInfo> copy =
-      Compiler::CompileScript(source2_string, Handle<String>(), 0, 0, false,
+      Compiler::CompileScript(copy_source, Handle<String>(), 0, 0, false,
                               Handle<Context>(isolate->native_context()), NULL,
                               &cache, CONSUME_CACHED_DATA, NOT_NATIVES_CODE);
   CHECK_NE(*orig, *copy);
-  CHECK(Script::cast(copy->script())->source() == *source2_string);
+  CHECK(Script::cast(copy->script())->source() == *copy_source);
 
   Handle<JSFunction> copy_fun =
       isolate->factory()->NewFunctionFromSharedFunctionInfo(