1 files changed, 53 insertions, 0 deletions
diff --git a/tests/common.py b/tests/common.py
new file mode 100644
index 0000000..adc3ec2
--- /dev/null
+++ b/tests/common.py
@@ -0,0 +1,53 @@
+# coding: utf-8
+
+"""
+Provides test-related code that can be used by all tests.
+
+"""
+
+import os
+
+import examples
+
+
+DATA_DIR = 'tests/data'
+EXAMPLES_DIR = os.path.dirname(examples.__file__)
+
+
+def get_data_path(file_name):
+    return os.path.join(DATA_DIR, file_name)
+
+
+class AssertStringMixin:
+
+    """A unittest.TestCase mixin to check string equality."""
+
+    def assertString(self, actual, expected):
+        """
+        Assert that the given strings are equal and have the same type.
+
+        """
+        # Show both friendly and literal versions.
+        message = """String mismatch: %%s\
+
+
+        Expected: \"""%s\"""
+        Actual:   \"""%s\"""
+
+        Expected: %s
+        Actual:   %s""" % (expected, actual, repr(expected), repr(actual))
+
+        self.assertEquals(actual, expected, message % "different characters")
+
+        details = "types different: %s != %s" % (repr(type(expected)), repr(type(actual)))
+        self.assertEquals(type(expected), type(actual), message % details)
+
+
+class AssertIsMixin:
+
+    """A unittest.TestCase mixin adding assertIs()."""
+
+    # unittest.assertIs() is not available until Python 2.7:
+    #   http://docs.python.org/library/unittest.html#unittest.TestCase.assertIsNone
+    def assertIs(self, first, second):
+        self.assertTrue(first is second, msg="%s is not %s" % (repr(first), repr(second)))