[V8] Fixed infinite loop in Debug::PrepareStep

test/cctest/test-debug.cc

Index: test/cctest/test-debug.cc
diff --git a/test/cctest/test-debug.cc b/test/cctest/test-debug.cc
index 25a75103e3704e5f7938877b8d56fee2ea9b2ffc..409e46aac538dab507e97a1bfd811d0394e2ac14 100644
--- a/test/cctest/test-debug.cc
+++ b/test/cctest/test-debug.cc
@@ -3825,6 +3825,47 @@ TEST(DebugStepFunctionCall) {
 }
 
 
+// Test that step in works with Function.call.apply.
+TEST(DebugStepFunctionCallApply) {
+  DebugLocalContext env;
+  v8::Isolate* isolate = env->GetIsolate();
+  v8::HandleScope scope(isolate);
+
+  // Create a function for testing stepping.
+  v8::Local<v8::Function> foo =
+      CompileFunction(&env,
+                      "function bar() { }"
+                      "function foo(){ debugger;"
+                      "                Function.call.apply(bar);"

[yurys, 2015/06/16 10:37:15]

Can you add one more test for a deeper case, something like

Function.call.apply(Function.call, [Function.call, bar])?

[kozy, 2015/06/16 10:49:58]

Done.

+                      "}",
+                      "foo");
+
+  // Register a debug event listener which steps and counts.
+  v8::Debug::SetDebugEventListener(DebugEventStep);
+  step_action = StepIn;
+
+  // Check stepping where the if condition in bar is false.
+  break_point_hit_count = 0;
+  foo->Call(env->Global(), 0, NULL);
+  CHECK_EQ(4, break_point_hit_count);
+
+  v8::Debug::SetDebugEventListener(NULL);
+  CheckDebuggerUnloaded();
+
+  // Register a debug event listener which just counts.
+  v8::Debug::SetDebugEventListener(DebugEventBreakPointHitCount);
+
+  break_point_hit_count = 0;
+  foo->Call(env->Global(), 0, NULL);
+
+  // Without stepping only the debugger statement is hit.
+  CHECK_EQ(1, break_point_hit_count);
+
+  v8::Debug::SetDebugEventListener(NULL);
+  CheckDebuggerUnloaded();
+}
+
+
 // Tests that breakpoint will be hit if it's set in script.
 TEST(PauseInScript) {
   DebugLocalContext env;