Allow an extra comma before the end of a function call. (#3520)

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

tests/jerry/es2015/function-call.js

@@ -0,0 +1,38 @@
+// 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.
+
+function check_syntax_error (code)
+{
+  try {
+    eval (code)
+    assert (false)
+  } catch (e) {
+    assert (e instanceof SyntaxError)
+  }
+}
+
+function f(...a)
+{
+  return a.length
+}
+
+check_syntax_error ("f(,)")
+check_syntax_error ("f(,1)")
+check_syntax_error ("f(1,,)")
+check_syntax_error ("f(1,,2)")
+
+assert(f(10) === 1)
+assert(f(10,) === 1)
+assert(f(10,11) === 2)
+assert(f(10,11,) === 2)