Python lib2to3.pytree.Leaf() Examples

def test_changed(self):
        l1 = pytree.Leaf(100, "f")
        self.assertFalse(l1.was_changed)
        l1.changed()
        self.assertTrue(l1.was_changed)

        l1 = pytree.Leaf(100, "f")
        n1 = pytree.Node(1000, [l1])
        self.assertFalse(n1.was_changed)
        n1.changed()
        self.assertTrue(n1.was_changed)

        l1 = pytree.Leaf(100, "foo")
        l2 = pytree.Leaf(100, "+")
        l3 = pytree.Leaf(100, "bar")
        n1 = pytree.Node(1000, [l1, l2, l3])
        n2 = pytree.Node(1000, [n1])
        self.assertFalse(l1.was_changed)
        self.assertFalse(n1.was_changed)
        self.assertFalse(n2.was_changed)

        n1.changed()
        self.assertTrue(n1.was_changed)
        self.assertTrue(n2.was_changed)
        self.assertFalse(l1.was_changed) 

def test_changed(self):
        l1 = pytree.Leaf(100, "f")
        self.assertFalse(l1.was_changed)
        l1.changed()
        self.assertTrue(l1.was_changed)

        l1 = pytree.Leaf(100, "f")
        n1 = pytree.Node(1000, [l1])
        self.assertFalse(n1.was_changed)
        n1.changed()
        self.assertTrue(n1.was_changed)

        l1 = pytree.Leaf(100, "foo")
        l2 = pytree.Leaf(100, "+")
        l3 = pytree.Leaf(100, "bar")
        n1 = pytree.Node(1000, [l1, l2, l3])
        n2 = pytree.Node(1000, [n1])
        self.assertFalse(l1.was_changed)
        self.assertFalse(n1.was_changed)
        self.assertFalse(n2.was_changed)

        n1.changed()
        self.assertTrue(n1.was_changed)
        self.assertTrue(n2.was_changed)
        self.assertFalse(l1.was_changed) 

def test_remove(self):
        l1 = pytree.Leaf(100, "foo")
        l2 = pytree.Leaf(100, "foo")
        n1 = pytree.Node(1000, [l1, l2])
        n2 = pytree.Node(1000, [n1])

        self.assertEqual(n1.remove(), 0)
        self.assertEqual(n2.children, [])
        self.assertEqual(l1.parent, n1)
        self.assertEqual(n1.parent, None)
        self.assertEqual(n2.parent, None)
        self.assertFalse(n1.was_changed)
        self.assertTrue(n2.was_changed)

        self.assertEqual(l2.remove(), 1)
        self.assertEqual(l1.remove(), 0)
        self.assertEqual(n1.children, [])
        self.assertEqual(l1.parent, None)
        self.assertEqual(n1.parent, None)
        self.assertEqual(n2.parent, None)
        self.assertTrue(n1.was_changed)
        self.assertTrue(n2.was_changed) 

def suitify(parent):
    """
    Turn the stuff after the first colon in parent's children
    into a suite, if it wasn't already
    """
    for node in parent.children:
        if node.type == syms.suite:
            # already in the prefered format, do nothing
            return

    # One-liners have no suite node, we have to fake one up
    for i, node in enumerate(parent.children):
        if node.type == token.COLON:
            break
    else:
        raise ValueError(u"No class suite and no ':'!")
    # Move everything into a suite node
    suite = Node(syms.suite, [Newline(), Leaf(token.INDENT, indentation(node) + indentation_step(node))])
    one_node = parent.children[i+1]
    one_node.remove()
    one_node.prefix = u''
    suite.append_child(one_node)
    parent.append_child(suite) 

def suitify(parent):
    """
    Turn the stuff after the first colon in parent's children
    into a suite, if it wasn't already
    """
    for node in parent.children:
        if node.type == syms.suite:
            # already in the prefered format, do nothing
            return

    # One-liners have no suite node, we have to fake one up
    for i, node in enumerate(parent.children):
        if node.type == token.COLON:
            break
    else:
        raise ValueError(u"No class suite and no ':'!")
    # Move everything into a suite node
    suite = Node(syms.suite, [Newline(), Leaf(token.INDENT, indentation(node) + indentation_step(node))])
    one_node = parent.children[i+1]
    one_node.remove()
    one_node.prefix = u''
    suite.append_child(one_node)
    parent.append_child(suite) 

def test_node_set_child(self):
        l1 = pytree.Leaf(100, "foo")
        n1 = pytree.Node(1000, [l1])

        l2 = pytree.Leaf(100, "bar")
        n1.set_child(0, l2)
        self.assertEqual(l1.parent, None)
        self.assertEqual(l2.parent, n1)
        self.assertEqual(n1.children, [l2])

        n2 = pytree.Node(1000, [l1])
        n2.set_child(0, n1)
        self.assertEqual(l1.parent, None)
        self.assertEqual(n1.parent, n2)
        self.assertEqual(n2.parent, None)
        self.assertEqual(n2.children, [n1])

        self.assertRaises(IndexError, n1.set_child, 4, l2)
        # I don't care what it raises, so long as it's an exception
        self.assertRaises(Exception, n1.set_child, 0, list) 

def test_remove_parentless(self):
        n1 = pytree.Node(1000, [])
        n1.remove()
        self.assertEqual(n1.parent, None)

        l1 = pytree.Leaf(100, "foo")
        l1.remove()
        self.assertEqual(l1.parent, None) 

def test_leaf_constructor_prefix(self):
        for prefix in ("xyz_", ""):
            l1 = pytree.Leaf(100, "self", prefix=prefix)
            self.assertTrue(str(l1), prefix + "self")
            self.assertEqual(l1.prefix, prefix) 

def test_node_constructor_prefix(self):
        for prefix in ("xyz_", ""):
            l1 = pytree.Leaf(100, "self")
            l2 = pytree.Leaf(100, "foo", prefix="_")
            n1 = pytree.Node(1000, [l1, l2], prefix=prefix)
            self.assertTrue(str(n1), prefix + "self_foo")
            self.assertEqual(n1.prefix, prefix)
            self.assertEqual(l1.prefix, prefix)
            self.assertEqual(l2.prefix, "_") 

def test_post_order(self):
        l1 = pytree.Leaf(100, "foo")
        l2 = pytree.Leaf(100, "bar")
        l3 = pytree.Leaf(100, "fooey")
        c1 = pytree.Node(1000, [l1, l2])
        n1 = pytree.Node(1000, [c1, l3])
        self.assertEqual(list(n1.post_order()), [l1, l2, c1, l3, n1]) 

def add_kwarg(self, l_nodes, s_kwd, n_expr):
        # XXX All this prefix-setting may lose comments (though rarely)
        n_expr.prefix = u""
        n_argument = pytree.Node(self.syms.argument,
                                 (Name(s_kwd),
                                  pytree.Leaf(token.EQUAL, u"="),
                                  n_expr))
        if l_nodes:
            l_nodes.append(Comma())
            n_argument.prefix = u" "
        l_nodes.append(n_argument) 

def future_import(feature, node):
    """
    This seems to work
    """
    root = find_root(node)

    if does_tree_import(u"__future__", feature, node):
        return

    # Look for a shebang or encoding line
    shebang_encoding_idx = None

    for idx, node in enumerate(root.children):
        # Is it a shebang or encoding line?
        if is_shebang_comment(node) or is_encoding_comment(node):
            shebang_encoding_idx = idx
        if is_docstring(node):
            # skip over docstring
            continue
        names = check_future_import(node)
        if not names:
            # not a future statement; need to insert before this
            break
        if feature in names:
            # already imported
            return

    import_ = FromImport(u'__future__', [Leaf(token.NAME, feature, prefix=" ")])
    if shebang_encoding_idx == 0 and idx == 0:
        # If this __future__ import would go on the first line,
        # detach the shebang / encoding prefix from the current first line.
        # and attach it to our new __future__ import node.
        import_.prefix = root.children[0].prefix
        root.children[0].prefix = u''
        # End the __future__ import line with a newline and add a blank line
        # afterwards:
    children = [import_ , Newline()]
    root.insert_child(idx, Node(syms.simple_stmt, children)) 

def future_import2(feature, node):
    """
    An alternative to future_import() which might not work ...
    """
    root = find_root(node)

    if does_tree_import(u"__future__", feature, node):
        return

    insert_pos = 0
    for idx, node in enumerate(root.children):
        if node.type == syms.simple_stmt and node.children and \
           node.children[0].type == token.STRING:
            insert_pos = idx + 1
            break

    for thing_after in root.children[insert_pos:]:
        if thing_after.type == token.NEWLINE:
            insert_pos += 1
            continue

        prefix = thing_after.prefix
        thing_after.prefix = u""
        break
    else:
        prefix = u""

    import_ = FromImport(u"__future__", [Leaf(token.NAME, feature, prefix=u" ")])

    children = [import_, Newline()]
    root.insert_child(insert_pos, Node(syms.simple_stmt, children, prefix=prefix)) 

def is_shebang_comment(node):
    """
    Comments are prefixes for Leaf nodes. Returns whether the given node has a
    prefix that looks like a shebang line or an encoding line:

        #!/usr/bin/env python
        #!/usr/bin/python3
    """
    return bool(re.match(SHEBANG_REGEX, node.prefix)) 

def is_encoding_comment(node):
    """
    Comments are prefixes for Leaf nodes. Returns whether the given node has a
    prefix that looks like an encoding line:

        # coding: utf-8
        # encoding: utf-8
        # -*- coding: <encoding name> -*-
        # vim: set fileencoding=<encoding name> :
    """
    return bool(re.match(ENCODING_REGEX, node.prefix)) 

def transform(self, node, results):
        single = results.get("single")
        if single:
            # Make a fake listmaker
            fake = pytree.Node(syms.listmaker, [single.clone()])
            single.replace(fake)
            items = fake
        else:
            items = results["items"]

        # Build the contents of the literal
        literal = [pytree.Leaf(token.LBRACE, u"{")]
        literal.extend(n.clone() for n in items.children)
        literal.append(pytree.Leaf(token.RBRACE, u"}"))
        # Set the prefix of the right brace to that of the ')' or ']'
        literal[-1].prefix = items.next_sibling.prefix
        maker = pytree.Node(syms.dictsetmaker, literal)
        maker.prefix = node.prefix

        # If the original was a one tuple, we need to remove the extra comma.
        if len(maker.children) == 4:
            n = maker.children[2]
            n.remove()
            maker.children[-1].prefix = n.prefix

        # Finally, replace the set call with our shiny new literal.
        return maker 

def test_deprecated_prefix_methods(self):
            l = pytree.Leaf(100, "foo")
            with warnings.catch_warnings(record=True) as w:
                warnings.simplefilter("always", DeprecationWarning)
                self.assertEqual(l.get_prefix(), "")
                l.set_prefix("hi")
            self.assertEqual(l.prefix, "hi")
            self.assertEqual(len(w), 2)
            for warning in w:
                self.assertTrue(warning.category is DeprecationWarning)
            self.assertEqual(str(w[0].message), "get_prefix() is deprecated; " \
                                 "use the prefix property")
            self.assertEqual(str(w[1].message), "set_prefix() is deprecated; " \
                                 "use the prefix property") 

def test_leaf_str(self):
        l1 = pytree.Leaf(100, "foo")
        self.assertEqual(str(l1), "foo")
        l2 = pytree.Leaf(100, "foo", context=(" ", (10, 1)))
        self.assertEqual(str(l2), " foo") 

def test_depth(self):
        l1 = pytree.Leaf(100, "foo")
        l2 = pytree.Leaf(100, "bar")
        n2 = pytree.Node(1000, [l1, l2])
        n3 = pytree.Node(1000, [])
        n1 = pytree.Node(1000, [n2, n3])

        self.assertEqual(l1.depth(), 2)
        self.assertEqual(n3.depth(), 1)
        self.assertEqual(n1.depth(), 0) 

def test_leaves(self):
        l1 = pytree.Leaf(100, "foo")
        l2 = pytree.Leaf(100, "bar")
        l3 = pytree.Leaf(100, "fooey")
        n2 = pytree.Node(1000, [l1, l2])
        n3 = pytree.Node(1000, [l3])
        n1 = pytree.Node(1000, [n2, n3])

        self.assertEqual(list(n1.leaves()), [l1, l2, l3]) 

def test_replace_with_list(self):
        l1 = pytree.Leaf(100, "foo")
        l2 = pytree.Leaf(100, "+")
        l3 = pytree.Leaf(100, "bar")
        n1 = pytree.Node(1000, [l1, l2, l3])

        l2.replace([pytree.Leaf(100, "*"), pytree.Leaf(100, "*")])
        self.assertEqual(str(n1), "foo**bar")
        self.assertIsInstance(n1.children, list) 

def test_replace(self):
        l1 = pytree.Leaf(100, "foo")
        l2 = pytree.Leaf(100, "+")
        l3 = pytree.Leaf(100, "bar")
        n1 = pytree.Node(1000, [l1, l2, l3])
        self.assertEqual(n1.children, [l1, l2, l3])
        self.assertIsInstance(n1.children, list)
        self.assertFalse(n1.was_changed)
        l2new = pytree.Leaf(100, "-")
        l2.replace(l2new)
        self.assertEqual(n1.children, [l1, l2new, l3])
        self.assertIsInstance(n1.children, list)
        self.assertTrue(n1.was_changed) 

def test_get_suffix(self):
        l1 = pytree.Leaf(100, "foo", prefix="a")
        l2 = pytree.Leaf(100, "bar", prefix="b")
        n1 = pytree.Node(1000, [l1, l2])

        self.assertEqual(l1.get_suffix(), l2.prefix)
        self.assertEqual(l2.get_suffix(), "")
        self.assertEqual(n1.get_suffix(), "")

        l3 = pytree.Leaf(100, "bar", prefix="c")
        n2 = pytree.Node(1000, [n1, l3])

        self.assertEqual(n1.get_suffix(), l3.prefix)
        self.assertEqual(l3.get_suffix(), "")
        self.assertEqual(n2.get_suffix(), "") 

def test_node_prefix(self):
        l1 = pytree.Leaf(100, "foo")
        self.assertEqual(l1.prefix, "")
        n1 = pytree.Node(1000, [l1])
        self.assertEqual(n1.prefix, "")
        n1.prefix = " "
        self.assertEqual(n1.prefix, " ")
        self.assertEqual(l1.prefix, " ") 

def test_node_str(self):
        l1 = pytree.Leaf(100, "foo")
        l2 = pytree.Leaf(100, "bar", context=(" ", (1, 0)))
        n1 = pytree.Node(1000, [l1, l2])
        self.assertEqual(str(n1), "foo bar") 

def test_node_repr(self):
        l1 = pytree.Leaf(100, "foo")
        l2 = pytree.Leaf(100, "bar", context=(" ", (1, 0)))
        n1 = pytree.Node(1000, [l1, l2])
        self.assertEqual(repr(n1),
                         "Node(1000, [%s, %s])" % (repr(l1), repr(l2))) 

def test_node(self):
        l1 = pytree.Leaf(100, "foo")
        l2 = pytree.Leaf(200, "bar")
        n1 = pytree.Node(1000, [l1, l2])
        self.assertEqual(n1.type, 1000)
        self.assertEqual(n1.children, [l1, l2]) 

def test_leaf_equality(self):
        l1 = pytree.Leaf(100, "foo")
        l2 = pytree.Leaf(100, "foo", context=(" ", (1, 0)))
        self.assertEqual(l1, l2)
        l3 = pytree.Leaf(101, "foo")
        l4 = pytree.Leaf(100, "bar")
        self.assertNotEqual(l1, l3)
        self.assertNotEqual(l1, l4) 

def test_leaf_str_numeric_value(self):
        # Make sure that the Leaf's value is stringified. Failing to
        #  do this can cause a TypeError in certain situations.
        l1 = pytree.Leaf(2, 5)
        l1.prefix = "foo_"
        self.assertEqual(str(l1), "foo_5") 

def test_leaf(self):
        l1 = pytree.Leaf(100, "foo")
        self.assertEqual(l1.type, 100)
        self.assertEqual(l1.value, "foo")