Fix block-scoped var/function redeclarations (#4080)

JerryScript-DCO-1.0-Signed-off-by: Dániel Bátyai daniel.batyai@h-lab.eu

tests/jerry/es.next/block-var-redecl.js

@@ -0,0 +1,56 @@
+// 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 (script)
+{
+  try
+  {
+    eval (script);
+    assert (false);
+  }
+  catch (e)
+  {
+    assert (e instanceof SyntaxError);
+  }
+}
+
+eval("function f(){}; var f;");
+eval("var f; function f(){};");
+
+eval("function f(){}; { var f; }")
+eval("{ var f; } function f(){};")
+
+eval("{ function f(){}; } var f;")
+eval("var f; { function f(){}; }")
+
+check_syntax_error ("{ function f(){}; var f; }");
+check_syntax_error ("{ var f; function f(){}; }");
+
+eval("{ { function f(){}; } var f; }")
+eval("{ var f; { function f(){}; } }")
+
+check_syntax_error ("{ function f(){}; { var f; } }")
+check_syntax_error ("{ { var f; } function f(){}; }")
+
+eval("{ { function f(){}; } { var f; } }")
+eval("{ { var f; } { function f(){}; } }")
+
+eval("function g(){ function f(){}; var f; }")
+eval("function g(){ var f; function f(){}; }")
+
+eval("function g(){ function f(){}; { var f; } }")
+eval("function g(){ { var f; } function f(){}; }")
+
+eval("function g(){ { function f(){}; } var f; }")
+eval("function g(){ var f; { function f(){}; } }")