jscript: Throw proper error when invoking non-method builtin.

dlls/jscript/dispex.c

@@ -560,6 +560,9 @@ static HRESULT invoke_prop_func(jsdisp_t *This, IDispatch *jsthis, dispex_prop_t
     case PROP_BUILTIN: {
         jsval_t vthis;
 
+        if(!prop->u.p->invoke)
+            return JS_E_FUNCTION_EXPECTED;
+
         if(flags == DISPATCH_CONSTRUCT && (prop->flags & PROPF_METHOD)) {
             WARN("%s is not a constructor\n", debugstr_w(prop->name));
             return E_INVALIDARG;

dlls/jscript/tests/api.js

@@ -2611,6 +2611,8 @@ testException(function() {delete false;}, "E_INVALID_DELETE");
 testException(function() {undefined.toString();}, "E_OBJECT_EXPECTED");
 testException(function() {null.toString();}, "E_OBJECT_EXPECTED");
 testException(function() {RegExp.prototype.toString.call(new Object());}, "E_REGEXP_EXPECTED");
+testException(function() {/a/.lastIndex();}, "E_NOT_FUNC");
+testException(function() {"a".length();}, "E_NOT_FUNC");
 
 testException(function() { return arguments.callee(); }, "E_STACK_OVERFLOW");
 

dlls/mshtml/tests/documentmode.js

@@ -1307,6 +1307,19 @@ sync_test("builtins_diffs", function() {
     }catch(e) {
         ok(e.number === 0xa1398 - 0x80000000, "RegExp.toString with non-regexp: exception = " + e.number);
     }
+
+    try {
+        /a/.lastIndex();
+        ok(false, "/a/.lastIndex(): expected exception");
+    }catch(e) {
+        ok(e.number === 0xa138a - 0x80000000, "/a/.lastIndex(): exception = " + e.number);
+    }
+    try {
+        "a".length();
+        ok(false, "\"a\".length(): expected exception");
+    }catch(e) {
+        ok(e.number === 0xa138a - 0x80000000, "\"a\".length(): exception = " + e.number);
+    }
 });
 
 sync_test("__proto__", function() {