Implement Proxy object [[Get]] internal method (#3604)

The algorithm is based on ECMA-262 v6, 9.5.8

JerryScript-DCO-1.0-Signed-off-by: Adam Szilagyi aszilagy@inf.u-szeged.hu

tests/jerry/es2015/proxy_create.js

@@ -29,13 +29,6 @@ try {
   assert(e instanceof TypeError);
 }
 
-try {
-  proxy.a;
-  assert(false);
-} catch (e) {
-  assert(e instanceof TypeError);
-}
-
 try {
   new Proxy(undefined, undefined);
   assert(false);

tests/jerry/es2015/proxy_get.js

@@ -12,7 +12,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-// TODO: Update these tests when the internal routine has been implemented
+// Copyright 2015 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
 
 var target = {};
 var handler = { get (target) {
@@ -26,7 +28,7 @@ try {
   proxy.a
   assert(false);
 } catch (e) {
-  assert(e instanceof TypeError);
+  assert(e === 42);
 }
 
 try {
@@ -34,7 +36,7 @@ try {
   proxy[2];
   assert(false);
 } catch (e) {
-  assert(e instanceof TypeError);
+  assert(e === 42);
 }
 
 try {
@@ -42,5 +44,91 @@ try {
   proxy + "foo";
   assert(false);
 } catch (e) {
-  assert(e instanceof TypeError);
+  assert(e === 42);
+}
+
+// test basic funcionality
+var target = {
+  target_one: 1,
+  prop: "value"
+};
+
+var handler = {handler: 1};
+var proxy = new Proxy(target, handler);
+
+assert(proxy.prop === "value");
+assert(proxy.nothing === undefined);
+assert(proxy.handler === undefined);
+
+handler.get = function () {return "value 2"};
+
+assert(proxy.prop === "value 2");
+assert(proxy.nothing === "value 2");
+assert(proxy.handler === "value 2");
+
+var handler2 = new Proxy({get: function() {return "value 3"}}, {});
+var proxy2 = new Proxy(target, handler2);
+
+assert(proxy2.prop === "value 3");
+assert(proxy2.nothing === "value 3");
+assert(proxy2.handler === "value 3");
+
+// test when get throws an error
+var handler = new Proxy({}, {get: function() {throw 42;}});
+var proxy = new Proxy ({}, handler);
+
+try {
+  proxy.prop;
+  assert(false);
+} catch (e) {
+  assert(e === 42);
+}
+
+// test when trap is undefined
+var handler = new Proxy({}, {get: function() {return undefined}});
+var target = {prop: "value"};
+var proxy = new Proxy(target, handler);
+assert(proxy.prop === "value");
+assert(proxy.prop2 === undefined);
+
+// test when invariants gets violated
+var target = {};
+var handler = {get: function(r, p){if (p != "key4") return "value"}}
+var proxy = new Proxy(target, handler);
+
+assert(proxy.key === "value");
+assert(proxy.key2 === "value");
+assert(proxy.key3 === "value");
+assert(proxy.key4 === undefined);
+
+Object.defineProperty(target, "key", {
+  configurable: false,
+  writable: false,
+  value: "different value"
+});
+
+try {
+  proxy.key;
+  assert(false);
+} catch (e) {
+  assert(e instanceof TypeError)
+}
+
+Object.defineProperty(target, "key2", {
+  configurable: false,
+  get: function() {return "different value"}
+});
+
+assert(proxy.key2 === "value");
+
+Object.defineProperty(target, "key3", {
+  configurable: false,
+  set: function() {}
+});
+
+try {
+  proxy.key3;
+  assert(false);
+} catch (e) {
+  assert(e instanceof TypeError)
 }

tests/jerry/es2015/proxy_revocable.js

@@ -23,12 +23,7 @@ var revocable = Proxy.revocable(target, handler);
 
 var proxy = revocable.proxy;
 
-try {
-  proxy.a; // FIXME: this should return 5 when proxy.[[Get]] has been implemted
-  assert(false);
-} catch (e) {
-  assert(e instanceof TypeError);
-}
+assert(proxy.a === 5);
 
 revocable.revoke();
 

tests/jerry/es2015/proxy_set.js

@@ -29,10 +29,3 @@ try {
   assert(e instanceof TypeError);
 }
 
-try {
-  // 22.1.3.6.11.b
-  Array.prototype.fill.call(proxy, 'foo', 0, 5);
-  assert(false);
-} catch (e) {
-  assert(e instanceof TypeError);
-}