Create namespace with references for modules (#4646)

JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg zherczeg.u-szeged@partner.samsung.com

tests/jerry/es.next/module-circular-02.mjs

@@ -0,0 +1,85 @@
+// Copyright JS Foundation and other contributors, http://js.foundation
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import * as o from "module-circular-01.mjs"
+
+if (o.early != "Loaded")
+{
+  // The scope of module-circular-01.mjs is initialized and functions are usable
+  // However, the module script has not been executed
+
+  assert(o.a === undefined)
+  o.early()
+  assert(o.a === "X")
+
+  try {
+    o.b
+    assert(false)
+  } catch (e) {
+    assert(e instanceof ReferenceError)
+  }
+
+  try {
+    o.a = "X"
+    assert(false)
+  } catch (e) {
+    assert(e instanceof TypeError)
+  }
+
+  assert(o[Symbol.toStringTag] === "Module")
+
+  var result = Object.getOwnPropertyDescriptor(o, "a")
+  assert(result.value === "X")
+  assert(result.configurable === false)
+  assert(result.enumerable === true)
+  assert(result.writable === true)
+
+  try {
+    Object.getOwnPropertyDescriptor(o, "b")
+    assert(false)
+  } catch (e) {
+    assert(e instanceof ReferenceError)
+  }
+
+  result = Object.getOwnPropertyDescriptor(o, Symbol.toStringTag)
+  assert(result.value === "Module")
+  assert(result.configurable === false)
+  assert(result.enumerable === false)
+  assert(result.writable === false)
+
+  Object.defineProperty(o, "a", { value: "X" })
+
+  try {
+    Object.defineProperty(o, "a", { value: "Y" })
+    assert(false)
+  } catch (e) {
+    assert(e instanceof TypeError)
+  }
+
+  try {
+    Object.defineProperty(o, "b", { value:5 })
+    assert(false)
+  } catch (e) {
+    assert(e instanceof ReferenceError)
+  }
+
+  Object.defineProperty(o, Symbol.toStringTag, { value: "Module", writable:false })
+
+  try {
+    Object.defineProperty(o, Symbol.toStringTag, { writable:true })
+    assert(false)
+  } catch (e) {
+    assert(e instanceof TypeError)
+  }
+}