[MERGE #6012 @MikeHolman] Add JsIsCallable API

Merge pull request #6012 from MikeHolman:callable

Author: MikeHolman

lib/Jsrt/ChakraCore.h

@@ -1202,6 +1202,22 @@ JsGetErrorPrototype(_Out_ JsValueRef * result);
 CHAKRA_API
 JsGetIteratorPrototype(_Out_ JsValueRef * result);
 
+/// <summary>
+///      Returns a value that indicates whether an object is callable.
+/// </summary>
+/// <remarks>
+///     Requires an active script context.
+/// </remarks>
+/// <param name="object">The object to test.</param>
+/// <param name="isConstructor">If the object is callable, <c>true</c>, <c>false</c> otherwise.</param>
+/// <returns>
+///     The code <c>JsNoError</c> if the operation succeeded, a failure code otherwise.
+/// </returns>
+CHAKRA_API
+JsIsCallable(
+    _In_ JsValueRef object,
+    _Out_ bool *isCallable);
+
 /// <summary>
 ///      Returns a value that indicates whether an object is a constructor.
 /// </summary>

lib/Jsrt/Core/JsrtCore.cpp

@@ -1392,17 +1392,25 @@ CHAKRA_API JsAllocRawData(_In_ JsRuntimeHandle runtimeHandle, _In_ size_t sizeIn
     });
 }
 
+CHAKRA_API JsIsCallable(_In_ JsValueRef object, _Out_ bool *isCallable)
+{
+    return ContextAPINoScriptWrapper_NoRecord([&](Js::ScriptContext *scriptContext) -> JsErrorCode {
+        VALIDATE_INCOMING_OBJECT(object, scriptContext);
+        PARAM_NOT_NULL(isCallable);
+
+        *isCallable = Js::JavascriptConversion::IsCallable(object);
+
+        return JsNoError;
+    });
+}
+
 CHAKRA_API JsIsConstructor(_In_ JsValueRef object, _Out_ bool *isConstructor)
 {
-    return ContextAPIWrapper<JSRT_MAYBE_TRUE>([&](Js::ScriptContext *scriptContext, TTDRecorder& _actionEntryPopper) -> JsErrorCode {
-        PERFORM_JSRT_TTD_RECORD_ACTION_NOT_IMPLEMENTED(scriptContext);
+    return ContextAPINoScriptWrapper_NoRecord([&](Js::ScriptContext *scriptContext) -> JsErrorCode {
         VALIDATE_INCOMING_OBJECT(object, scriptContext);
         PARAM_NOT_NULL(isConstructor);
 
-        Js::RecyclableObject * instance = Js::VarTo<Js::RecyclableObject>(object);
-        AssertMsg(scriptContext->GetThreadContext()->IsScriptActive(), "Caller is expected to be under ContextAPIWrapper!");
-
-        *isConstructor = Js::JavascriptOperators::IsConstructor(instance);
+        *isConstructor = Js::JavascriptOperators::IsConstructor(object);
 
         return JsNoError;
     });

lib/Jsrt/JsrtCommonExports.inc

@@ -136,6 +136,7 @@
     JsGetWeakReferenceValue
     JsHasOwnProperty
     JsHasOwnItem
+    JsIsCallable
     JsIsConstructor
     JsObjectDefineProperty
     JsObjectDefinePropertyFull