test: add mocks module for commonly-mocked objects

Includes:
 - MockInterval
 - MockFeature
 - MockSource

test/mocks.py

@@ -0,0 +1,35 @@
+"""Mocks for testing"""
+
+class MockInterval():
+    """Mock Interval object for testing Feature"""
+    def __init__(self, start, end):
+        self.start = start
+        self.end = end
+        self.duration = end - start
+
+    def to_json(self):
+        return {"start": self.start, "end": self.end}
+
+class MockFeature():
+    """Mock feature object for testing"""
+    def __init__(self, interval, source=None):
+        self.interval = interval
+        self.source = source
+
+    def to_json(self):
+        return {"interval": self.interval}
+
+class MockSource():
+    """Mock Source object for testing Feature"""
+    def __init__(self, source=None, path=None):
+        self.source = source
+        self.path = path
+
+    def __str__(self):
+        return self.source
+
+    def to_json(self):
+        return {"source": self.source}
+
+    def __eq__(self, other):
+        return self.source == other.source