webkitgtk-2.16.5HEADwebkitgtk-2.16.5master

1 files changed, 253 insertions, 0 deletions

diff --git a/Source/JavaScriptCore/debugger/DebuggerScope.cpp b/Source/JavaScriptCore/debugger/DebuggerScope.cpp
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+++ b/Source/JavaScriptCore/debugger/DebuggerScope.cpp
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+/*
+ * Copyright (C) 2008-2009, 2014, 2016 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+ */
+
+#include "config.h"
+#include "DebuggerScope.h"
+
+#include "JSLexicalEnvironment.h"
+#include "JSCInlines.h"
+#include "JSWithScope.h"
+
+namespace JSC {
+
+STATIC_ASSERT_IS_TRIVIALLY_DESTRUCTIBLE(DebuggerScope);
+
+const ClassInfo DebuggerScope::s_info = { "DebuggerScope", &Base::s_info, 0, CREATE_METHOD_TABLE(DebuggerScope) };
+
+DebuggerScope* DebuggerScope::create(VM& vm, JSScope* scope)
+{
+    Structure* structure = scope->globalObject()->debuggerScopeStructure();
+    DebuggerScope* debuggerScope = new (NotNull, allocateCell<DebuggerScope>(vm.heap)) DebuggerScope(vm, structure, scope);
+    debuggerScope->finishCreation(vm);
+    return debuggerScope;
+}
+
+DebuggerScope::DebuggerScope(VM& vm, Structure* structure, JSScope* scope)
+    : JSNonFinalObject(vm, structure)
+{
+    ASSERT(scope);
+    m_scope.set(vm, this, scope);
+}
+
+void DebuggerScope::finishCreation(VM& vm)
+{
+    Base::finishCreation(vm);
+}
+
+void DebuggerScope::visitChildren(JSCell* cell, SlotVisitor& visitor)
+{
+    DebuggerScope* thisObject = jsCast<DebuggerScope*>(cell);
+    ASSERT_GC_OBJECT_INHERITS(thisObject, info());
+    JSObject::visitChildren(thisObject, visitor);
+    visitor.append(thisObject->m_scope);
+    visitor.append(thisObject->m_next);
+}
+
+String DebuggerScope::className(const JSObject* object)
+{
+    const DebuggerScope* scope = jsCast<const DebuggerScope*>(object);
+    // We cannot assert that scope->isValid() because the TypeProfiler may encounter an invalidated
+    // DebuggerScope in its log entries. We just need to handle it appropriately as below.
+    if (!scope->isValid())
+        return String();
+    JSObject* thisObject = JSScope::objectAtScope(scope->jsScope());
+    return thisObject->methodTable()->className(thisObject);
+}
+
+bool DebuggerScope::getOwnPropertySlot(JSObject* object, ExecState* exec, PropertyName propertyName, PropertySlot& slot)
+{
+    DebuggerScope* scope = jsCast<DebuggerScope*>(object);
+    if (!scope->isValid())
+        return false;
+    JSObject* thisObject = JSScope::objectAtScope(scope->jsScope());
+    slot.setThisValue(JSValue(thisObject));
+
+    // By default, JSObject::getPropertySlot() will look in the DebuggerScope's prototype
+    // chain and not the wrapped scope, and JSObject::getPropertySlot() cannot be overridden
+    // to behave differently for the DebuggerScope.
+    //
+    // Instead, we'll treat all properties in the wrapped scope and its prototype chain as
+    // the own properties of the DebuggerScope. This is fine because the WebInspector
+    // does not presently need to distinguish between what's owned at each level in the
+    // prototype chain. Hence, we'll invoke getPropertySlot() on the wrapped scope here
+    // instead of getOwnPropertySlot().
+    bool result = thisObject->getPropertySlot(exec, propertyName, slot);
+    if (result && slot.isValue() && slot.getValue(exec, propertyName) == jsTDZValue()) {
+        // FIXME:
+        // We hit a scope property that has the TDZ empty value.
+        // Currently, we just lie to the inspector and claim that this property is undefined.
+        // This is not ideal and we should fix it.
+        // https://bugs.webkit.org/show_bug.cgi?id=144977
+        slot.setValue(slot.slotBase(), DontEnum, jsUndefined());
+        return true;
+    }
+    return result;
+}
+
+bool DebuggerScope::put(JSCell* cell, ExecState* exec, PropertyName propertyName, JSValue value, PutPropertySlot& slot)
+{
+    DebuggerScope* scope = jsCast<DebuggerScope*>(cell);
+    ASSERT(scope->isValid());
+    if (!scope->isValid())
+        return false;
+    JSObject* thisObject = JSScope::objectAtScope(scope->jsScope());
+    slot.setThisValue(JSValue(thisObject));
+    return thisObject->methodTable()->put(thisObject, exec, propertyName, value, slot);
+}
+
+bool DebuggerScope::deleteProperty(JSCell* cell, ExecState* exec, PropertyName propertyName)
+{
+    DebuggerScope* scope = jsCast<DebuggerScope*>(cell);
+    ASSERT(scope->isValid());
+    if (!scope->isValid())
+        return false;
+    JSObject* thisObject = JSScope::objectAtScope(scope->jsScope());
+    return thisObject->methodTable()->deleteProperty(thisObject, exec, propertyName);
+}
+
+void DebuggerScope::getOwnPropertyNames(JSObject* object, ExecState* exec, PropertyNameArray& propertyNames, EnumerationMode mode)
+{
+    DebuggerScope* scope = jsCast<DebuggerScope*>(object);
+    ASSERT(scope->isValid());
+    if (!scope->isValid())
+        return;
+    JSObject* thisObject = JSScope::objectAtScope(scope->jsScope());
+    thisObject->methodTable()->getPropertyNames(thisObject, exec, propertyNames, mode);
+}
+
+bool DebuggerScope::defineOwnProperty(JSObject* object, ExecState* exec, PropertyName propertyName, const PropertyDescriptor& descriptor, bool shouldThrow)
+{
+    DebuggerScope* scope = jsCast<DebuggerScope*>(object);
+    ASSERT(scope->isValid());
+    if (!scope->isValid())
+        return false;
+    JSObject* thisObject = JSScope::objectAtScope(scope->jsScope());
+    return thisObject->methodTable()->defineOwnProperty(thisObject, exec, propertyName, descriptor, shouldThrow);
+}
+
+DebuggerScope* DebuggerScope::next()
+{
+    ASSERT(isValid());
+    if (!m_next && m_scope->next()) {
+        VM& vm = *m_scope->vm();
+        DebuggerScope* nextScope = create(vm, m_scope->next());
+        m_next.set(vm, this, nextScope);
+    }
+    return m_next.get();
+}
+
+void DebuggerScope::invalidateChain()
+{
+    if (!isValid())
+        return;
+
+    DebuggerScope* scope = this;
+    while (scope) {
+        DebuggerScope* nextScope = scope->m_next.get();
+        scope->m_next.clear();
+        scope->m_scope.clear(); // This also marks this scope as invalid.
+        scope = nextScope;
+    }
+}
+
+bool DebuggerScope::isCatchScope() const
+{
+    return m_scope->isCatchScope();
+}
+
+bool DebuggerScope::isFunctionNameScope() const
+{
+    return m_scope->isFunctionNameScopeObject();
+}
+
+bool DebuggerScope::isWithScope() const
+{
+    return m_scope->isWithScope();
+}
+
+bool DebuggerScope::isGlobalScope() const
+{
+    return m_scope->isGlobalObject();
+}
+
+bool DebuggerScope::isGlobalLexicalEnvironment() const
+{
+    return m_scope->isGlobalLexicalEnvironment();
+}
+
+bool DebuggerScope::isClosureScope() const
+{
+    // In the current debugger implementation, every function or eval will create an
+    // lexical environment object. Hence, a lexical environment object implies a
+    // function or eval scope.
+    return m_scope->isVarScope() || m_scope->isLexicalScope();
+}
+
+bool DebuggerScope::isNestedLexicalScope() const
+{
+    return m_scope->isNestedLexicalScope();
+}
+
+String DebuggerScope::name() const
+{
+    SymbolTable* symbolTable = m_scope->symbolTable(*vm());
+    if (!symbolTable)
+        return String();
+
+    CodeBlock* codeBlock = symbolTable->rareDataCodeBlock();
+    if (!codeBlock)
+        return String();
+
+    return String::fromUTF8(codeBlock->inferredName());
+}
+
+DebuggerLocation DebuggerScope::location() const
+{
+    SymbolTable* symbolTable = m_scope->symbolTable(*vm());
+    if (!symbolTable)
+        return DebuggerLocation();
+
+    CodeBlock* codeBlock = symbolTable->rareDataCodeBlock();
+    if (!codeBlock)
+        return DebuggerLocation();
+
+    ScriptExecutable* executable = codeBlock->ownerScriptExecutable();
+    return DebuggerLocation(executable);
+}
+
+JSValue DebuggerScope::caughtValue(ExecState* exec) const
+{
+    ASSERT(isCatchScope());
+    JSLexicalEnvironment* catchEnvironment = jsCast<JSLexicalEnvironment*>(m_scope.get());
+    SymbolTable* catchSymbolTable = catchEnvironment->symbolTable();
+    RELEASE_ASSERT(catchSymbolTable->size() == 1);
+    PropertyName errorName(catchSymbolTable->begin(catchSymbolTable->m_lock)->key.get());
+    PropertySlot slot(m_scope.get(), PropertySlot::InternalMethodType::Get);
+    bool success = catchEnvironment->getOwnPropertySlot(catchEnvironment, exec, errorName, slot);
+    RELEASE_ASSERT(success && slot.isValue());
+    return slot.getValue(exec, errorName);
+}
+
+} // namespace JSC