Issue 3593 - stop sharing v8::Isolate among tests

test/JsEngine.cpp

Index: test/JsEngine.cpp
diff --git a/test/JsEngine.cpp b/test/JsEngine.cpp
index b26c794ffabb4a2a6ec2c19fe0adfceffed30c21..3a115808c3f230362b1941cbccc25fe6bd86a8e9 100644
--- a/test/JsEngine.cpp
+++ b/test/JsEngine.cpp
@@ -188,3 +188,25 @@ TEST(NewJsEngineTest, GlobalPropertyTest)
   ASSERT_EQ(foo.AsString(), "bar");
 }
 
+TEST(NewJsEngineTest, MemoryLeak_NoCircularReferences)
+{
+  std::weak_ptr<AdblockPlus::JsEngine> weakJsEngine;
+  {
+    weakJsEngine = AdblockPlus::JsEngine::New();
+  }
+  EXPECT_FALSE(weakJsEngine.lock());
+}
+
+TEST(NewJsEngineTest, MemoryLeak_NoLeak)
+{
+  // v8::Isolate by default requires 32MB (depends on platform), so if there is
+  // a memory leak than we will run out of memory on 32 bit platform because it
+  // will allocate 32000 MB which is less than 2GB where it reaches out of
+  // memory. Even on android where it allocates initially 16MB, the test still
+  // makes sense.

[hub, 2017/05/19 19:20:21]

I am not convinced by this test. We run mostly on 64-bits on our development
machine (Linux or macOS at least) where the address space is larger.

[sergei, 2017/05/22 08:08:55]

On 64 bit platform it will take too long to try to run out of memory, so it's
just a simple attempt to catch when we do something wrong instead of nothing at
all, do you have some alternative?

BTW, I'm not sure that we mostly run on 64-bits because currently targeted by us
platforms are Windows (32 and 64 bits) and Android (where we use only 32 bits
version). I agree that in a long term 32 bit will be likely thrown away but it
seems it won't happen withing nearest couple years.

+  int i = 1000;
+  while (i-->0)

[hub, 2017/05/19 19:20:21]

Shouldn't this be written 
  while (i-- > 0)
?

Also I'd rather see a
  for (int i = 0; i < 1000; i++)

but this is strict a matter of preference.

[sergei, 2017/05/22 08:08:55]

Done.

+  {
+    AdblockPlus::JsEngine::New();
+  }
+}