Tools/Scripts/webkitpy/common/memoized_unittest.py

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import unittest

from webkitpy.common.memoized import memoized


class _TestObject(object):
    def __init__(self):
        self.callCount = 0

    @memoized
    def memoized_add(self, argument):
        """testing docstring"""
        self.callCount += 1
        if argument is None:
            return None  # Avoid the TypeError from None + 1
        return argument + 1


class MemoizedTest(unittest.TestCase):
    def test_caching(self):
        test = _TestObject()
        test.callCount = 0
        self.assertEqual(test.memoized_add(1), 2)
        self.assertEqual(test.callCount, 1)
        self.assertEqual(test.memoized_add(1), 2)
        self.assertEqual(test.callCount, 1)

        # Validate that callCount is working as expected.
        self.assertEqual(test.memoized_add(2), 3)
        self.assertEqual(test.callCount, 2)

    def test_tearoff(self):
        test = _TestObject()
        # Make sure that get()/tear-offs work:
        tearoff = test.memoized_add
        self.assertEqual(tearoff(4), 5)
        self.assertEqual(test.callCount, 1)