Test generation of test suite.

Author: johnthagen

cpplint_junit.py

@@ -17,6 +17,13 @@
 
 class CpplintError(object):
     def __init__(self, file, line, message):
+        """Constructor.
+
+        Args:
+            file (str): File error originated on.
+            line (int): Line error originated on.
+            message (str): Error message.
+        """
         self.file = file
         self.line = line
         self.message = message
@@ -57,15 +64,14 @@ def parse_cpplint(file_name):
         return errors
 
 
-def generate_test_suite(errors, output_file):
+def generate_test_suite(errors):
     """Writes a JUnit test file from parsed cpplint failures.
 
     Args:
         errors (Dict[str, List[CpplintError]]): Parsed cpplint failures.
-        output_file (str): File path to JUnit XML output.
 
     Returns:
-        Nothing.
+        ElementTree.ElementTree: XML test suite.
     """
     test_suite = ElementTree.Element('testsuite')
     test_suite.attrib['errors'] = str(len(errors))
@@ -85,8 +91,7 @@ def generate_test_suite(errors, output_file):
                                    line=str(error.line),
                                    message='{}: {}'.format(error.line, error.message))
 
-    tree = ElementTree.ElementTree(test_suite)
-    tree.write(output_file, encoding='utf-8', xml_declaration=True)
+    return ElementTree.ElementTree(test_suite)
 
 
 def main():
@@ -104,7 +109,8 @@ def main():
         return EXIT_FAILURE
 
     if len(errors) > 0:
-        generate_test_suite(errors, args.output_file)
+        tree = generate_test_suite(errors)
+        tree.write(args.output_file, encoding='utf-8', xml_declaration=True)
 
     return EXIT_SUCCESS
 

test.py

@@ -2,9 +2,10 @@
 
 """cpplint-junit tests."""
 
+import sys
 import unittest
 
-from cpplint_junit import parse_cpplint
+from cpplint_junit import CpplintError, generate_test_suite, parse_arguments, parse_cpplint
 
 
 class ParseCpplintTestCase(unittest.TestCase):
@@ -113,5 +114,39 @@ def test_all(self):
                          'Could not find a newline character at the end of the file.  '
                          '[whitespace/ending_newline] [5]')
 
+
+class GenerateTestSuiteTestCase(unittest.TestCase):
+    def test_single(self):
+        errors = {'file_name':
+                  [CpplintError('file_name',
+                                4,
+                                'error message')]}
+        tree = generate_test_suite(errors)
+        root = tree.getroot()
+        self.assertEqual(root.get('errors'), str(1))
+        self.assertEqual(root.get('failures'), str(0))
+        self.assertEqual(root.get('tests'), str(1))
+
+        test_case_element = root.find('testcase')
+        self.assertEqual(test_case_element.get('name'), 'file_name')
+
+        error_element = test_case_element.find('error')
+        self.assertEqual(error_element.get('file'), 'file_name')
+        self.assertEqual(error_element.get('line'), str(4))
+        self.assertEqual(error_element.get('message'), '4: error message')
+
+
+class ParseArgumentsTestCase(unittest.TestCase):
+    def test_no_arguments(self):
+        with self.assertRaises(SystemExit):
+            # Suppress argparse stderr.
+            class NullWriter:
+                def write(self, s):
+                    pass
+
+            sys.stderr = NullWriter()
+            parse_arguments()
+
+
 if __name__ == '__main__':
     unittest.main()