Python context.ContextStack类代码示例

    def test_get__precedence(self):
        """
        Test that get() respects the order of precedence (later items first).

        """
        context = ContextStack({"foo": "bar"}, {"foo": "buzz"})
        self.assertEqual(context.get("foo"), "buzz")

    def test_get__key_present(self):
        """
        Test getting a key.

        """
        context = ContextStack({"foo": "bar"})
        self.assertEqual(context.get("foo"), "bar")

    def test_dot_notation__missing_attr_or_key(self):
        name = "foo.bar.baz.bak"
        stack = ContextStack({"foo": {"bar": {}}})
        self.assertString(stack.get(name), "")

        stack = ContextStack({"foo": Attachable(bar=Attachable())})
        self.assertString(stack.get(name), "")

    def test_get__fallback(self):
        """
        Check that first-added stack items are queried on context misses.

        """
        context = ContextStack({"fuzz": "buzz"}, {"foo": "bar"})
        self.assertEqual(context.get("fuzz"), "buzz")

    def test_get__key_missing(self):
        """
        Test getting a missing key.

        """
        context = ContextStack()
        self.assertString(context.get("foo"), "")

    def test_get__default(self):
        """
        Test that get() respects the default value.

        """
        context = ContextStack()
        self.assertEqual(context.get("foo", "bar"), "bar")

    def test_dot_notation__missing_part_terminates_search(self):
        """
        Test that dotted name resolution terminates on a later part not found.

        Check that if a later dotted name part is not found in the result from
        the former resolution, then name resolution terminates rather than
        starting the search over with the next element of the context stack.
        From the spec (interpolation section)--

          5) If any name parts were retained in step 1, each should be resolved
          against a context stack containing only the result from the former
          resolution.  If any part fails resolution, the result should be considered
          falsey, and should interpolate as the empty string.

        This test case is equivalent to the test case in the following pull
        request:

          https://github.com/mustache/spec/pull/48

        """
        stack = ContextStack({'a': {'b': 'A.B'}}, {'a': 'A'})
        self.assertEqual(stack.get('a'), 'A')
        self.assertException(KeyNotFoundError, "Key 'a.b' not found: missing 'b'", stack.get, "a.b")
        stack.pop()
        self.assertEqual(stack.get('a.b'), 'A.B')

    def test_get__single_dot(self):
        """
        Test getting a single dot (".").

        """
        context = ContextStack("a", "b")
        self.assertEqual(context.get("."), "b")

    def test_dot_notation__list(self):
        """ Test that an index interger after a dot correctly grabs the item
        if the parent is a list.

        """
        name = "foo.1"
        stack = ContextStack({"foo": ['Ignore me.', 'Choose me!']})
        self.assertEqual(stack.get(name), "Choose me!")

    def test_top(self):
        key = "foo"
        context = ContextStack({key: "bar"}, {key: "buzz"})
        self.assertEqual(context.get(key), "buzz")

        top = context.top()
        self.assertEqual(top, {"foo": "buzz"})
        # Make sure calling top() didn't remove the item from the stack.
        self.assertEqual(context.get(key), "buzz")

    def test_dot_notation__dict(self):
        name = "foo.bar"
        stack = ContextStack({"foo": {"bar": "baz"}})
        self.assertEqual(stack.get(name), "baz")

        # Works all the way down
        name = "a.b.c.d.e.f.g"
        stack = ContextStack({"a": {"b": {"c": {"d": {"e": {"f": {"g": "w00t!"}}}}}}})
        self.assertEqual(stack.get(name), "w00t!")

    def test_dot_notation_escaped(self):
        name = "foo\.bar"
        stack = ContextStack({"foo.bar": "baz"})
        self.assertEqual(stack.get(name), "baz")

        # Works at any component depth.
        name = "zoo.foo\.bar"
        stack = ContextStack({"zoo": {"foo.bar": "baz"}})
        self.assertEqual(stack.get(name), "baz")

    def test_dot_notation__user_object(self):
        name = "foo.bar"
        stack = ContextStack({"foo": Attachable(bar="baz")})
        self.assertEqual(stack.get(name), "baz")

        # Works on multiple levels, too
        name = "a.b.c.d.e.f.g"
        A = Attachable
        stack = ContextStack({"a": A(b=A(c=A(d=A(e=A(f=A(g="w00t!"))))))})
        self.assertEqual(stack.get(name), "w00t!")

    def test_push(self):
        """
        Test push().

        """
        key = "foo"
        context = ContextStack({key: "bar"})
        self.assertEqual(context.get(key), "bar")

        context.push({key: "buzz"})
        self.assertEqual(context.get(key), "buzz")

    def test_pop(self):
        """
        Test pop().

        """
        key = "foo"
        context = ContextStack({key: "bar"}, {key: "buzz"})
        self.assertEqual(context.get(key), "buzz")

        item = context.pop()
        self.assertEqual(item, {"foo": "buzz"})
        self.assertEqual(context.get(key), "bar")