TestcaseParser: variable binds of testcase parser instance cat be updated.

ate/testcase.py

@@ -6,7 +6,7 @@ class TestcaseParser(object):
     def __init__(self, variables_binds={}):
         self.variables_binds = variables_binds
 
-    def parse(self, testcase_template):
+    def parse(self, testcase_template, variables_binds={}):
         """ parse testcase_template, replace all variables with bind value.
         variables marker: ${variable}.
         @param testcase_template
@@ -30,7 +30,12 @@ class TestcaseParser(object):
                     "msg": "user created successfully."
                 }
             }
+        @param variables_binds
+            variable binds of testcase parser instance will be updated.
         """
+        if variables_binds:
+            self.variables_binds.update(variables_binds)
+
         return self.substitute(testcase_template)
 
     def substitute(self, content):

test/test_testcase.py

@@ -79,3 +79,21 @@ class TestcaseParserUnittest(unittest.TestCase):
         }
         with self.assertRaises(exception.ParamsError):
             self.testcase_parser.parse(testcase)
+
+    def test_parse_testcase_with_new_variable_binds(self):
+        testcase = {
+            "request": {
+                "url": "http://127.0.0.1:5000/api/users/${uid}",
+                "method": "${method}"
+            }
+        }
+        new_variable_binds = {
+            "method": "GET"
+        }
+        parsed_testcase = self.testcase_parser.parse(testcase, new_variable_binds)
+
+        self.assertIn("method", self.testcase_parser.variables_binds)
+        self.assertEqual(
+            parsed_testcase["request"]["method"],
+            new_variable_binds["method"]
+        )