4 files changed, 36 insertions, 22 deletions

diff --git a/src/script/api/qscriptengine.cpp b/src/script/api/qscriptengine.cpp
index 3b1cb9d..8f8c86d 100644
--- a/src/script/api/qscriptengine.cpp
+++ b/src/script/api/qscriptengine.cpp
@@ -2733,8 +2733,7 @@ QScriptContext *QScriptEngine::pushContext()
    return the new top frame. (might be the same as exec if a new stackframe was not needed) or 0 if stack overflow
 */
 JSC::CallFrame *QScriptEnginePrivate::pushContext(JSC::CallFrame *exec, JSC::JSValue _thisObject,
-                                                  const JSC::ArgList& args, JSC::JSObject *callee, bool calledAsConstructor,
-                                                  bool clearScopeChain)
+                                                  const JSC::ArgList& args, JSC::JSObject *callee, bool calledAsConstructor)
 {
     JSC::JSValue thisObject = _thisObject;
     if (!callee) {
@@ -2777,11 +2776,7 @@ JSC::CallFrame *QScriptEnginePrivate::pushContext(JSC::CallFrame *exec, JSC::JSV
             newCallFrame[++dst] = *it;
         newCallFrame += argc + JSC::RegisterFile::CallFrameHeaderSize;
 
-        if (!clearScopeChain) {
-            newCallFrame->init(0, /*vPC=*/0, exec->scopeChain(), exec, flags | ShouldRestoreCallFrame, argc, callee);
-        } else {
-            newCallFrame->init(0, /*vPC=*/0, globalExec()->scopeChain(), exec, flags | ShouldRestoreCallFrame, argc, callee);
-        }
+        newCallFrame->init(0, /*vPC=*/0, globalExec()->scopeChain(), exec, flags | ShouldRestoreCallFrame, argc, callee);
     } else {
         setContextFlags(newCallFrame, flags);
 #if ENABLE(JIT)
diff --git a/src/script/api/qscriptengine_p.h b/src/script/api/qscriptengine_p.h
index 6c82522..09ecaf2 100644
--- a/src/script/api/qscriptengine_p.h
+++ b/src/script/api/qscriptengine_p.h
@@ -248,7 +248,7 @@ public:
     static JSC::Register *thisRegisterForFrame(JSC::ExecState *frame);
 
     JSC::CallFrame *pushContext(JSC::CallFrame *exec, JSC::JSValue thisObject, const JSC::ArgList& args,
-                                JSC::JSObject *callee, bool calledAsConstructor = false, bool clearScopeChain = false);
+                                JSC::JSObject *callee, bool calledAsConstructor = false);
     void popContext();
 
     void mark(JSC::MarkStack& markStack);
diff --git a/src/script/bridge/qscriptdeclarativeclass.cpp b/src/script/bridge/qscriptdeclarativeclass.cpp
index 3fa8943..01886e0 100644
--- a/src/script/bridge/qscriptdeclarativeclass.cpp
+++ b/src/script/bridge/qscriptdeclarativeclass.cpp
@@ -397,27 +397,19 @@ QScriptValue QScriptDeclarativeClass::scopeChainValue(QScriptContext *context, i
   By default, the `this' object of the new context is the Global Object.
   The context's \l{QScriptContext::callee()}{callee}() will be invalid.
 
-  Unlike pushContext(), the default scope chain is reset to include
-  only the global object and the QScriptContext's activation object.
+  The context's scope chain initially contains only the Global Object
+  and the QScriptContext's activation object.
 
-  \sa QScriptEngine::popContext()
+  This function behaves exactly like QScriptEngine::popContext();
+  it exists because QScriptEngine::popContext() used to have a bug
+  that caused the scope chain of the new context to be incorrect.
 */
 QScriptContext * QScriptDeclarativeClass::pushCleanContext(QScriptEngine *engine)
 {
     if (!engine)
         return 0;
 
-    QScriptEnginePrivate *d = QScriptEnginePrivate::get(engine);
-    QScript::APIShim shim(d);
-
-    JSC::CallFrame* newFrame = d->pushContext(d->currentFrame, 
-                                              d->currentFrame->globalData().dynamicGlobalObject,
-                                              JSC::ArgList(), /*callee = */0, false, true);
-
-    if (engine->agent())
-        engine->agent()->contextPush();
-
-    return d->contextForFrame(newFrame);
+    return engine->pushContext();
 }
 
 QScriptDeclarativeClass::~QScriptDeclarativeClass()
diff --git a/tests/auto/qscriptengine/tst_qscriptengine.cpp b/tests/auto/qscriptengine/tst_qscriptengine.cpp
index b1b416c..514d29a 100644
--- a/tests/auto/qscriptengine/tst_qscriptengine.cpp
+++ b/tests/auto/qscriptengine/tst_qscriptengine.cpp
@@ -250,6 +250,7 @@ private slots:
     void stringListFromArrayWithEmptyElement();
     void collectQObjectWithCachedWrapper_data();
     void collectQObjectWithCachedWrapper();
+    void pushContext_noInheritedScope();
 };
 
 tst_QScriptEngine::tst_QScriptEngine()
@@ -6218,5 +6219,31 @@ void tst_QScriptEngine::collectQObjectWithCachedWrapper()
     QCOMPARE(ptr == 0, shouldBeCollected);
 }
 
+// QTBUG-18188
+void tst_QScriptEngine::pushContext_noInheritedScope()
+{
+    QScriptEngine eng;
+    eng.globalObject().setProperty("foo", 123);
+
+    QScriptContext *ctx1 = eng.pushContext();
+    QCOMPARE(ctx1->scopeChain().size(), 2);
+    ctx1->activationObject().setProperty("foo", 456);
+    QCOMPARE(eng.evaluate("foo").toInt32(), 456);
+
+    QScriptContext *ctx2 = eng.pushContext();
+    // The parent context's scope should not be inherited.
+    QCOMPARE(ctx2->scopeChain().size(), 2);
+    QCOMPARE(eng.evaluate("foo").toInt32(), 123);
+
+    ctx2->activationObject().setProperty("foo", 789);
+    QCOMPARE(eng.evaluate("foo").toInt32(), 789);
+
+    eng.popContext();
+    QCOMPARE(eng.evaluate("foo").toInt32(), 456);
+
+    eng.popContext();
+    QCOMPARE(eng.evaluate("foo").toInt32(), 123);
+}
+
 QTEST_MAIN(tst_QScriptEngine)
 #include "tst_qscriptengine.moc"