LibJS: Convert internal_get() to ThrowCompletionOr

Author: https://github.com/linusg
Commit: https://github.com/SerenityOS/serenity/commit/6c2b974db28
Pull-request: https://github.com/SerenityOS/serenity/pull/10266
Reviewed-by: https://github.com/IdanHo ✅

Meta/Lagom/Tools/CodeGenerators/LibWeb/WrapperGenerator.cpp

@@ -1392,7 +1392,7 @@ public:
 
     if (interface.extended_attributes.contains("CustomGet")) {
         generator.append(R"~~~(
-    virtual JS::Value internal_get(JS::PropertyName const&, JS::Value receiver) const override;
+    virtual JS::ThrowCompletionOr<JS::Value> internal_get(JS::PropertyName const&, JS::Value receiver) const override;
 )~~~");
     }
     if (interface.extended_attributes.contains("CustomSet")) {

Userland/Applications/Spreadsheet/JSIntegration.cpp

@@ -8,6 +8,7 @@
 #include "Spreadsheet.h"
 #include "Workbook.h"
 #include <LibJS/Lexer.h>
+#include <LibJS/Runtime/Completion.h>
 #include <LibJS/Runtime/Error.h>
 #include <LibJS/Runtime/GlobalObject.h>
 #include <LibJS/Runtime/Object.h>
@@ -101,7 +102,7 @@ SheetGlobalObject::~SheetGlobalObject()
 {
 }
 
-JS::Value SheetGlobalObject::internal_get(const JS::PropertyName& property_name, JS::Value receiver) const
+JS::ThrowCompletionOr<JS::Value> SheetGlobalObject::internal_get(const JS::PropertyName& property_name, JS::Value receiver) const
 {
     if (property_name.is_string()) {
         if (property_name.as_string() == "value") {

Userland/Applications/Spreadsheet/JSIntegration.h

@@ -8,6 +8,7 @@
 
 #include "Forward.h"
 #include <LibJS/Forward.h>
+#include <LibJS/Runtime/Completion.h>
 #include <LibJS/Runtime/GlobalObject.h>
 
 namespace Spreadsheet {
@@ -26,7 +27,7 @@ public:
 
     virtual ~SheetGlobalObject() override;
 
-    virtual JS::Value internal_get(JS::PropertyName const&, JS::Value receiver) const override;
+    virtual JS::ThrowCompletionOr<JS::Value> internal_get(JS::PropertyName const&, JS::Value receiver) const override;
     virtual bool internal_set(JS::PropertyName const&, JS::Value value, JS::Value receiver) override;
     virtual void initialize_global_object() override;
 

Userland/DevTools/HackStudio/Debugger/DebuggerGlobalJSObject.cpp

@@ -7,6 +7,7 @@
 #include "DebuggerGlobalJSObject.h"
 #include "Debugger.h"
 #include "DebuggerVariableJSObject.h"
+#include <LibJS/Runtime/Completion.h>
 #include <LibJS/Runtime/Object.h>
 #include <LibJS/Runtime/ProxyObject.h>
 
@@ -21,7 +22,7 @@ DebuggerGlobalJSObject::DebuggerGlobalJSObject()
     m_variables = lib->debug_info->get_variables_in_current_scope(regs);
 }
 
-JS::Value DebuggerGlobalJSObject::internal_get(JS::PropertyName const& property_name, JS::Value receiver) const
+JS::ThrowCompletionOr<JS::Value> DebuggerGlobalJSObject::internal_get(JS::PropertyName const& property_name, JS::Value receiver) const
 {
     if (m_variables.is_empty() || !property_name.is_string())
         return Base::internal_get(property_name, receiver);
@@ -36,8 +37,7 @@ JS::Value DebuggerGlobalJSObject::internal_get(JS::PropertyName const& property_
     if (js_value.has_value())
         return js_value.value();
     auto error_string = String::formatted("Variable {} of type {} is not convertible to a JS Value", property_name.as_string(), target_variable.type_name);
-    vm().throw_exception<JS::TypeError>(const_cast<DebuggerGlobalJSObject&>(*this), error_string);
-    return {};
+    return vm().throw_completion<JS::TypeError>(const_cast<DebuggerGlobalJSObject&>(*this), move(error_string));
 }
 
 bool DebuggerGlobalJSObject::internal_set(JS::PropertyName const& property_name, JS::Value value, JS::Value receiver)

Userland/DevTools/HackStudio/Debugger/DebuggerGlobalJSObject.h

@@ -8,6 +8,7 @@
 
 #include <AK/Weakable.h>
 #include <LibDebug/DebugInfo.h>
+#include <LibJS/Runtime/Completion.h>
 #include <LibJS/Runtime/GlobalObject.h>
 
 namespace HackStudio {
@@ -20,7 +21,7 @@ class DebuggerGlobalJSObject final
 public:
     DebuggerGlobalJSObject();
 
-    virtual JS::Value internal_get(JS::PropertyName const&, JS::Value receiver) const override;
+    virtual JS::ThrowCompletionOr<JS::Value> internal_get(JS::PropertyName const&, JS::Value receiver) const override;
     virtual bool internal_set(JS::PropertyName const&, JS::Value value, JS::Value receiver) override;
 
     Optional<JS::Value> debugger_to_js(const Debug::DebugInfo::VariableInfo&) const;

Userland/Libraries/LibJS/Runtime/ArgumentsObject.cpp

@@ -35,7 +35,7 @@ void ArgumentsObject::visit_edges(Cell::Visitor& visitor)
 }
 
 // 10.4.4.3 [[Get]] ( P, Receiver ), https://tc39.es/ecma262/#sec-arguments-exotic-objects-get-p-receiver
-Value ArgumentsObject::internal_get(PropertyName const& property_name, Value receiver) const
+ThrowCompletionOr<Value> ArgumentsObject::internal_get(PropertyName const& property_name, Value receiver) const
 {
     // 1. Let map be args.[[ParameterMap]].
     auto& map = *m_parameter_map;

Userland/Libraries/LibJS/Runtime/ArgumentsObject.h

@@ -25,7 +25,7 @@ public:
 
     virtual ThrowCompletionOr<Optional<PropertyDescriptor>> internal_get_own_property(PropertyName const&) const override;
     virtual ThrowCompletionOr<bool> internal_define_own_property(PropertyName const&, PropertyDescriptor const&) override;
-    virtual Value internal_get(PropertyName const&, Value receiver) const override;
+    virtual ThrowCompletionOr<Value> internal_get(PropertyName const&, Value receiver) const override;
     virtual bool internal_set(PropertyName const&, Value value, Value receiver) override;
     virtual bool internal_delete(PropertyName const&) override;
 

Userland/Libraries/LibJS/Runtime/Object.cpp

@@ -86,7 +86,7 @@ Value Object::get(PropertyName const& property_name) const
     VERIFY(property_name.is_valid());
 
     // 3. Return ? O.[[Get]](P, O).
-    return internal_get(property_name, this);
+    return TRY_OR_DISCARD(internal_get(property_name, this));
 }
 
 // 7.3.3 GetV ( V, P ) is defined as Value::get().
@@ -647,7 +647,7 @@ ThrowCompletionOr<bool> Object::internal_has_property(PropertyName const& proper
 }
 
 // 10.1.8 [[Get]] ( P, Receiver ), https://tc39.es/ecma262/#sec-ordinary-object-internal-methods-and-internal-slots-get-p-receiver
-Value Object::internal_get(PropertyName const& property_name, Value receiver) const
+ThrowCompletionOr<Value> Object::internal_get(PropertyName const& property_name, Value receiver) const
 {
     VERIFY(!receiver.is_empty());
     auto& vm = this->vm();
@@ -656,12 +656,12 @@ Value Object::internal_get(PropertyName const& property_name, Value receiver) co
     VERIFY(property_name.is_valid());
 
     // 2. Let desc be ? O.[[GetOwnProperty]](P).
-    auto descriptor = TRY_OR_DISCARD(internal_get_own_property(property_name));
+    auto descriptor = TRY(internal_get_own_property(property_name));
 
     // 3. If desc is undefined, then
     if (!descriptor.has_value()) {
         // a. Let parent be ? O.[[GetPrototypeOf]]().
-        auto* parent = TRY_OR_DISCARD(internal_get_prototype_of());
+        auto* parent = TRY(internal_get_prototype_of());
 
         // b. If parent is null, return undefined.
         if (!parent)
@@ -686,7 +686,7 @@ Value Object::internal_get(PropertyName const& property_name, Value receiver) co
         return js_undefined();
 
     // 8. Return ? Call(getter, Receiver).
-    return TRY_OR_DISCARD(vm.call(*getter, receiver));
+    return TRY(vm.call(*getter, receiver));
 }
 
 // 10.1.9 [[Set]] ( P, V, Receiver ), https://tc39.es/ecma262/#sec-ordinary-object-internal-methods-and-internal-slots-set-p-v-receiver

Userland/Libraries/LibJS/Runtime/Object.h

@@ -98,7 +98,7 @@ public:
     virtual ThrowCompletionOr<Optional<PropertyDescriptor>> internal_get_own_property(PropertyName const&) const;
     virtual ThrowCompletionOr<bool> internal_define_own_property(PropertyName const&, PropertyDescriptor const&);
     virtual ThrowCompletionOr<bool> internal_has_property(PropertyName const&) const;
-    virtual Value internal_get(PropertyName const&, Value receiver) const;
+    virtual ThrowCompletionOr<Value> internal_get(PropertyName const&, Value receiver) const;
     virtual bool internal_set(PropertyName const&, Value value, Value receiver);
     virtual bool internal_delete(PropertyName const&);
     virtual MarkedValueList internal_own_property_keys() const;

Userland/Libraries/LibJS/Runtime/ProxyObject.cpp

@@ -472,7 +472,7 @@ ThrowCompletionOr<bool> ProxyObject::internal_has_property(PropertyName const& p
 }
 
 // 10.5.8 [[Get]] ( P, Receiver ), https://tc39.es/ecma262/#sec-proxy-object-internal-methods-and-internal-slots-get-p-receiver
-Value ProxyObject::internal_get(PropertyName const& property_name, Value receiver) const
+ThrowCompletionOr<Value> ProxyObject::internal_get(PropertyName const& property_name, Value receiver) const
 {
     VERIFY(!receiver.is_empty());
 
@@ -485,10 +485,8 @@ Value ProxyObject::internal_get(PropertyName const& property_name, Value receive
     // 2. Let handler be O.[[ProxyHandler]].
 
     // 3. If handler is null, throw a TypeError exception.
-    if (m_is_revoked) {
-        vm.throw_exception<TypeError>(global_object, ErrorType::ProxyRevoked);
-        return {};
-    }
+    if (m_is_revoked)
+        return vm.throw_completion<TypeError>(global_object, ErrorType::ProxyRevoked);
 
     // 4. Assert: Type(handler) is Object.
     // 5. Let target be O.[[ProxyTarget]].
@@ -506,13 +504,11 @@ Value ProxyObject::internal_get(PropertyName const& property_name, Value receive
     // 6. goto 1
     //
     // In JS code: `h = {}; p = new Proxy({}, h); h.__proto__ = p; p.foo // or h.foo`
-    if (vm.did_reach_stack_space_limit()) {
-        vm.throw_exception<Error>(global_object, ErrorType::CallStackSizeExceeded);
-        return {};
-    }
+    if (vm.did_reach_stack_space_limit())
+        return vm.throw_completion<Error>(global_object, ErrorType::CallStackSizeExceeded);
 
     // 6. Let trap be ? GetMethod(handler, "get").
-    auto trap = TRY_OR_DISCARD(Value(&m_handler).get_method(global_object, vm.names.get));
+    auto trap = TRY(Value(&m_handler).get_method(global_object, vm.names.get));
 
     // 7. If trap is undefined, then
     if (!trap) {
@@ -521,28 +517,24 @@ Value ProxyObject::internal_get(PropertyName const& property_name, Value receive
     }
 
     // 8. Let trapResult be ? Call(trap, handler, « target, P, Receiver »).
-    auto trap_result = TRY_OR_DISCARD(vm.call(*trap, &m_handler, &m_target, property_name_to_value(vm, property_name), receiver));
+    auto trap_result = TRY(vm.call(*trap, &m_handler, &m_target, property_name_to_value(vm, property_name), receiver));
 
     // 9. Let targetDesc be ? target.[[GetOwnProperty]](P).
-    auto target_descriptor = TRY_OR_DISCARD(m_target.internal_get_own_property(property_name));
+    auto target_descriptor = TRY(m_target.internal_get_own_property(property_name));
 
     // 10. If targetDesc is not undefined and targetDesc.[[Configurable]] is false, then
     if (target_descriptor.has_value() && !*target_descriptor->configurable) {
         // a. If IsDataDescriptor(targetDesc) is true and targetDesc.[[Writable]] is false, then
         if (target_descriptor->is_data_descriptor() && !*target_descriptor->writable) {
             // i. If SameValue(trapResult, targetDesc.[[Value]]) is false, throw a TypeError exception.
-            if (!same_value(trap_result, *target_descriptor->value)) {
-                vm.throw_exception<TypeError>(global_object, ErrorType::ProxyGetImmutableDataProperty);
-                return {};
-            }
+            if (!same_value(trap_result, *target_descriptor->value))
+                return vm.throw_completion<TypeError>(global_object, ErrorType::ProxyGetImmutableDataProperty);
         }
         // b. If IsAccessorDescriptor(targetDesc) is true and targetDesc.[[Get]] is undefined, then
         if (target_descriptor->is_accessor_descriptor() && !*target_descriptor->get) {
             // i. If trapResult is not undefined, throw a TypeError exception.
-            if (!trap_result.is_undefined()) {
-                vm.throw_exception<TypeError>(global_object, ErrorType::ProxyGetNonConfigurableAccessor);
-                return {};
-            }
+            if (!trap_result.is_undefined())
+                return vm.throw_completion<TypeError>(global_object, ErrorType::ProxyGetNonConfigurableAccessor);
         }
     }
 

Userland/Libraries/LibJS/Runtime/ProxyObject.h

@@ -42,7 +42,7 @@ public:
     virtual ThrowCompletionOr<Optional<PropertyDescriptor>> internal_get_own_property(PropertyName const&) const override;
     virtual ThrowCompletionOr<bool> internal_define_own_property(PropertyName const&, PropertyDescriptor const&) override;
     virtual ThrowCompletionOr<bool> internal_has_property(PropertyName const&) const override;
-    virtual Value internal_get(PropertyName const&, Value receiver) const override;
+    virtual ThrowCompletionOr<Value> internal_get(PropertyName const&, Value receiver) const override;
     virtual bool internal_set(PropertyName const&, Value value, Value receiver) override;
     virtual bool internal_delete(PropertyName const&) override;
     virtual MarkedValueList internal_own_property_keys() const override;

Userland/Libraries/LibJS/Runtime/ReflectObject.cpp

@@ -171,7 +171,7 @@ JS_DEFINE_NATIVE_FUNCTION(ReflectObject::get)
     }
 
     // 4. Return ? target.[[Get]](key, receiver).
-    return target.as_object().internal_get(key, receiver);
+    return TRY_OR_DISCARD(target.as_object().internal_get(key, receiver));
 }
 
 // 28.1.6 Reflect.getOwnPropertyDescriptor ( target, propertyKey ), https://tc39.es/ecma262/#sec-reflect.getownpropertydescriptor

Userland/Libraries/LibJS/Runtime/TypedArray.h

@@ -309,7 +309,7 @@ public:
     }
 
     // 10.4.5.4 [[Get]] ( P, Receiver ), 10.4.5.4 [[Get]] ( P, Receiver )
-    virtual Value internal_get(PropertyName const& property_name, Value receiver) const override
+    virtual ThrowCompletionOr<Value> internal_get(PropertyName const& property_name, Value receiver) const override
     {
         VERIFY(!receiver.is_empty());
 

Userland/Libraries/LibJS/Runtime/Value.cpp

@@ -820,7 +820,7 @@ Value Value::get(GlobalObject& global_object, PropertyName const& property_name)
         return {};
 
     // 3. Return ? O.[[Get]](P, V).
-    return object->internal_get(property_name, *this);
+    return TRY_OR_DISCARD(object->internal_get(property_name, *this));
 }
 
 // 7.3.10 GetMethod ( V, P ), https://tc39.es/ecma262/#sec-getmethod

Userland/Libraries/LibWeb/Bindings/CSSStyleDeclarationWrapperCustom.cpp

@@ -18,7 +18,7 @@ JS::ThrowCompletionOr<bool> CSSStyleDeclarationWrapper::internal_has_property(JS
     return property_id != CSS::PropertyID::Invalid;
 }
 
-JS::Value CSSStyleDeclarationWrapper::internal_get(JS::PropertyName const& name, JS::Value receiver) const
+JS::ThrowCompletionOr<JS::Value> CSSStyleDeclarationWrapper::internal_get(JS::PropertyName const& name, JS::Value receiver) const
 {
     if (!name.is_string())
         return Base::internal_get(name, receiver);
@@ -26,8 +26,8 @@ JS::Value CSSStyleDeclarationWrapper::internal_get(JS::PropertyName const& name,
     if (property_id == CSS::PropertyID::Invalid)
         return Base::internal_get(name, receiver);
     if (auto maybe_property = impl().property(property_id); maybe_property.has_value())
-        return js_string(vm(), maybe_property->value->to_string());
-    return js_string(vm(), String::empty());
+        return { js_string(vm(), maybe_property->value->to_string()) };
+    return { js_string(vm(), String::empty()) };
 }
 
 bool CSSStyleDeclarationWrapper::internal_set(JS::PropertyName const& name, JS::Value value, JS::Value receiver)

Userland/Services/WebContent/ConsoleGlobalObject.cpp

@@ -75,7 +75,7 @@ JS::ThrowCompletionOr<bool> ConsoleGlobalObject::internal_has_property(JS::Prope
     return TRY(Object::internal_has_property(property_name)) || TRY(m_window_object->internal_has_property(property_name));
 }
 
-JS::Value ConsoleGlobalObject::internal_get(JS::PropertyName const& property_name, JS::Value receiver) const
+JS::ThrowCompletionOr<JS::Value> ConsoleGlobalObject::internal_get(JS::PropertyName const& property_name, JS::Value receiver) const
 {
     if (m_window_object->has_own_property(property_name))
         return m_window_object->internal_get(property_name, (receiver == this) ? m_window_object : receiver);

Userland/Services/WebContent/ConsoleGlobalObject.h

@@ -30,7 +30,7 @@ public:
     virtual JS::ThrowCompletionOr<Optional<JS::PropertyDescriptor>> internal_get_own_property(JS::PropertyName const& name) const override;
     virtual JS::ThrowCompletionOr<bool> internal_define_own_property(JS::PropertyName const& name, JS::PropertyDescriptor const& descriptor) override;
     virtual JS::ThrowCompletionOr<bool> internal_has_property(JS::PropertyName const& name) const override;
-    virtual JS::Value internal_get(JS::PropertyName const&, JS::Value) const override;
+    virtual JS::ThrowCompletionOr<JS::Value> internal_get(JS::PropertyName const&, JS::Value) const override;
     virtual bool internal_set(JS::PropertyName const&, JS::Value value, JS::Value receiver) override;
     virtual bool internal_delete(JS::PropertyName const& name) override;
     virtual JS::MarkedValueList internal_own_property_keys() const override;