[MERGE #5989 @akroshg] Exposing HasOwnItem API.

Merge pull request #5989 from akroshg:hasownitem

This will tell if the provided index is in the object.

Author: akroshg

bin/NativeTests/JsRTApiTest.cpp

@@ -252,6 +252,44 @@ namespace JsRTApiTest
         JsRTApiTest::RunWithAttributes(JsRTApiTest::DeleteObjectIndexedPropertyBug);
     }
 
+    void HasOwnItemTest(JsRuntimeAttributes attributes, JsRuntimeHandle runtime)
+    {
+        JsValueRef object;
+        REQUIRE(JsRunScript(_u("var obj = {a: [1,2], \"1\": 111}; obj.__proto__[3] = 333; obj;"), JS_SOURCE_CONTEXT_NONE, _u(""), &object) == JsNoError);
+
+        JsPropertyIdRef idRef = JS_INVALID_REFERENCE;
+        JsValueRef result = JS_INVALID_REFERENCE;
+        // delete property "a" triggers PathTypeHandler -> SimpleDictionaryTypeHandler
+        REQUIRE(JsGetPropertyIdFromName(_u("a"), &idRef) == JsNoError);
+        REQUIRE(JsGetProperty(object, idRef, &result) == JsNoError);
+        bool hasOwnItem = false;
+        REQUIRE(JsHasOwnItem(result, 0, &hasOwnItem) == JsNoError);
+        CHECK(hasOwnItem);
+
+        REQUIRE(JsHasOwnItem(result, 1, &hasOwnItem) == JsNoError);
+        CHECK(hasOwnItem);
+
+        REQUIRE(JsHasOwnItem(result, 2, &hasOwnItem) == JsNoError);
+        CHECK(!hasOwnItem); // It does not have item on index 2 - so we should not be able to find that.
+
+        REQUIRE(JsHasOwnItem(object, 1, &hasOwnItem) == JsNoError);
+        CHECK(hasOwnItem);
+
+        REQUIRE(JsHasOwnItem(object, 3, &hasOwnItem) == JsNoError);
+        CHECK(!hasOwnItem); // index 3 is on prototype.
+
+        bool has = false;
+        JsValueRef indexRef = JS_INVALID_REFERENCE;
+        REQUIRE(JsIntToNumber(3, &indexRef) == JsNoError);
+        REQUIRE(JsHasIndexedProperty(object, indexRef, &has) == JsNoError);
+        CHECK(has); // index 3 is prototype - so it should be able to find that.
+    }
+
+    TEST_CASE("ApiTest_HasOwnItemTest", "[ApiTest]")
+    {
+      JsRTApiTest::RunWithAttributes(JsRTApiTest::HasOwnItemTest);
+    }
+
     void CALLBACK ExternalObjectFinalizeCallback(void *data)
     {
         CHECK(data == (void *)0xdeadbeef);

lib/Jsrt/ChakraCore.h

@@ -961,6 +961,25 @@ CHAKRA_API
         _Out_ bool *hasOwnProperty);
 
 /// <summary>
+///     Determines whether an object has a non-inherited property.
+/// </summary>
+/// <remarks>
+///     Requires an active script context.
+/// </remarks>
+/// <param name="object">The object that may contain the item.</param>
+/// <param name="index">The index to find.</param>
+/// <param name="hasOwnProperty">Whether the object has the non-inherited
+/// property.</param> <returns>
+///     The code <c>JsNoError</c> if the operation succeeded, a failure code
+///     otherwise.
+/// </returns>
+CHAKRA_API
+    JsHasOwnItem(
+        _In_ JsValueRef object,
+        _In_ uint32_t index,
+        _Out_ bool* hasOwnItem);
+
+    /// <summary>
 ///     Write JS string value into char string buffer without a null terminator
 /// </summary>
 /// <remarks>

lib/Jsrt/Core/JsrtCore.cpp

@@ -516,6 +516,25 @@ JsExternalizeArrayBuffer(
     });
 }
 
+CHAKRA_API
+JsHasOwnItem(_In_ JsValueRef object,
+    _In_ uint32_t index,
+    _Out_ bool* hasOwnItem)
+{
+  return ContextAPIWrapper<true>(
+      [&](Js::ScriptContext* scriptContext,
+          TTDRecorder& _actionEntryPopper) -> JsErrorCode {
+
+        VALIDATE_INCOMING_OBJECT(object, scriptContext);
+        PARAM_NOT_NULL(hasOwnItem);
+
+        *hasOwnItem = !!Js::JavascriptOperators::HasOwnItem(
+            Js::VarTo<Js::RecyclableObject>(object), index);
+
+        return JsNoError;
+      });
+}
+
 CHAKRA_API
 JsDetachArrayBuffer(
     _In_ JsValueRef arrayBuffer)

lib/Jsrt/JsrtCommonExports.inc

@@ -135,6 +135,7 @@
     JsGetPropertyIdSymbolIterator
     JsGetWeakReferenceValue
     JsHasOwnProperty
+    JsHasOwnItem
     JsIsConstructor
     JsObjectDefineProperty
     JsObjectDefinePropertyFull