implement tests for TCL commands

tests/tclCommands/test_TclCommandOpenExcellon.py

@@ -0,0 +1,15 @@
+from FlatCAMObj import FlatCAMExcellon
+
+
+def test_open_excellon(self):
+    """
+    Test open excellon file
+    :param self:
+    :return:
+    """
+
+    self.fc.exec_command_test('open_excellon %s/%s -outname %s'
+                              % (self.gerber_files, self.excellon_filename, self.excellon_name))
+    excellon_obj = self.fc.collection.get_by_name(self.excellon_name)
+    self.assertTrue(isinstance(excellon_obj, FlatCAMExcellon), "Expected FlatCAMExcellon, instead, %s is %s"
+                    % (self.excellon_name, type(excellon_obj)))