path: root/tests/checkers/unittest_format.py

# Copyright (c) 2009-2011, 2014 LOGILAB S.A. (Paris, FRANCE) <contact@logilab.fr>
# Copyright (c) 2012 FELD Boris <lothiraldan@gmail.com>
# Copyright (c) 2013-2014 Google, Inc.
# Copyright (c) 2014-2020 Claudiu Popa <pcmanticore@gmail.com>
# Copyright (c) 2014 buck <buck.2019@gmail.com>
# Copyright (c) 2014 Arun Persaud <arun@nubati.net>
# Copyright (c) 2015 Harut <yes@harutune.name>
# Copyright (c) 2015 Ionel Cristian Maries <contact@ionelmc.ro>
# Copyright (c) 2016 Petr Pulc <petrpulc@gmail.com>
# Copyright (c) 2016 Derek Gustafson <degustaf@gmail.com>
# Copyright (c) 2017 Krzysztof Czapla <k.czapla68@gmail.com>
# Copyright (c) 2017 Łukasz Rogalski <rogalski.91@gmail.com>
# Copyright (c) 2017 James M. Allen <james.m.allen@gmail.com>
# Copyright (c) 2017 vinnyrose <vinnyrose@users.noreply.github.com>
# Copyright (c) 2018, 2020 Bryce Guinta <bryce.guinta@protonmail.com>
# Copyright (c) 2018 Bryce Guinta <bryce.paul.guinta@gmail.com>
# Copyright (c) 2018, 2020 Anthony Sottile <asottile@umich.edu>
# Copyright (c) 2019-2021 Pierre Sassoulas <pierre.sassoulas@gmail.com>
# Copyright (c) 2019 Hugo van Kemenade <hugovk@users.noreply.github.com>
# Copyright (c) 2019 Ashley Whetter <ashley@awhetter.co.uk>
# Copyright (c) 2020 hippo91 <guillaume.peillex@gmail.com>

# Licensed under the GPL: https://www.gnu.org/licenses/old-licenses/gpl-2.0.html
# For details: https://github.com/PyCQA/pylint/blob/master/COPYING

"""Check format checker helper functions"""

import os
import tempfile
import tokenize

import astroid

from pylint import lint, reporters
from pylint.checkers.format import FormatChecker
from pylint.testutils import CheckerTestCase, Message, _tokenize_str


class TestMultiStatementLine(CheckerTestCase):
    CHECKER_CLASS = FormatChecker

    def testSingleLineIfStmts(self):
        stmt = astroid.extract_node(
            """
        if True: pass  #@
        """
        )
        self.checker.config.single_line_if_stmt = False
        with self.assertAddsMessages(Message("multiple-statements", node=stmt.body[0])):
            self.visitFirst(stmt)
        self.checker.config.single_line_if_stmt = True
        with self.assertNoMessages():
            self.visitFirst(stmt)
        stmt = astroid.extract_node(
            """
        if True: pass  #@
        else:
            pass
        """
        )
        with self.assertAddsMessages(Message("multiple-statements", node=stmt.body[0])):
            self.visitFirst(stmt)

    def testSingleLineClassStmts(self):
        stmt = astroid.extract_node(
            """
        class MyError(Exception): pass  #@
        """
        )
        self.checker.config.single_line_class_stmt = False
        with self.assertAddsMessages(Message("multiple-statements", node=stmt.body[0])):
            self.visitFirst(stmt)
        self.checker.config.single_line_class_stmt = True
        with self.assertNoMessages():
            self.visitFirst(stmt)

        stmt = astroid.extract_node(
            """
        class MyError(Exception): a='a'  #@
        """
        )
        self.checker.config.single_line_class_stmt = False
        with self.assertAddsMessages(Message("multiple-statements", node=stmt.body[0])):
            self.visitFirst(stmt)
        self.checker.config.single_line_class_stmt = True
        with self.assertNoMessages():
            self.visitFirst(stmt)

        stmt = astroid.extract_node(
            """
        class MyError(Exception): a='a'; b='b'  #@
        """
        )
        self.checker.config.single_line_class_stmt = False
        with self.assertAddsMessages(Message("multiple-statements", node=stmt.body[0])):
            self.visitFirst(stmt)
        self.checker.config.single_line_class_stmt = True
        with self.assertAddsMessages(Message("multiple-statements", node=stmt.body[0])):
            self.visitFirst(stmt)

    def testTryExceptFinallyNoMultipleStatement(self):
        tree = astroid.extract_node(
            """
        try:  #@
            pass
        except:
            pass
        finally:
            pass"""
        )
        with self.assertNoMessages():
            self.visitFirst(tree)

    def visitFirst(self, tree):
        self.checker.process_tokens([])
        self.checker.visit_default(tree.body[0])

    def test_ellipsis_is_ignored(self):
        code = """
        from typing import overload
        @overload
        def concat2(arg1: str) -> str: ...
        """
        tree = astroid.extract_node(code)
        with self.assertNoMessages():
            self.visitFirst(tree)

        code = """
        def concat2(arg1: str) -> str: ...
        """
        stmt = astroid.extract_node(code)
        with self.assertAddsMessages(Message("multiple-statements", node=stmt.body[0])):
            self.visitFirst(stmt)


class TestSuperfluousParentheses(CheckerTestCase):
    CHECKER_CLASS = FormatChecker

    def testCheckKeywordParensHandlesValidCases(self):
        cases = [
            "if foo:",
            "if foo():",
            "if (x and y) or z:",
            "assert foo()",
            "assert ()",
            "if (1, 2) in (3, 4):",
            "if (a or b) in c:",
            "return (x for x in x)",
            "if (x for x in x):",
            "for x in (x for x in x):",
            "not (foo or bar)",
            "not (foo or bar) and baz",
        ]
        with self.assertNoMessages():
            for code in cases:
                self.checker._check_keyword_parentheses(_tokenize_str(code), 0)

    def testCheckKeywordParensHandlesUnnecessaryParens(self):
        cases = [
            (Message("superfluous-parens", line=1, args="if"), "if (foo):", 0),
            (Message("superfluous-parens", line=1, args="if"), "if ((foo, bar)):", 0),
            (Message("superfluous-parens", line=1, args="if"), "if (foo(bar)):", 0),
            (
                Message("superfluous-parens", line=1, args="return"),
                "return ((x for x in x))",
                0,
            ),
            (Message("superfluous-parens", line=1, args="not"), "not (foo)", 0),
            (Message("superfluous-parens", line=1, args="not"), "if not (foo):", 1),
            (Message("superfluous-parens", line=1, args="if"), "if (not (foo)):", 0),
            (Message("superfluous-parens", line=1, args="not"), "if (not (foo)):", 2),
            (
                Message("superfluous-parens", line=1, args="for"),
                "for (x) in (1, 2, 3):",
                0,
            ),
            (
                Message("superfluous-parens", line=1, args="if"),
                "if (1) in (1, 2, 3):",
                0,
            ),
        ]
        for msg, code, offset in cases:
            with self.assertAddsMessages(msg):
                self.checker._check_keyword_parentheses(_tokenize_str(code), offset)

    def testNoSuperfluousParensWalrusOperatorIf(self):
        """Parenthesis change the meaning of assignment in the walrus operator
        and so are not superfluous:"""
        code = "if (odd := is_odd(i))"
        offset = 0
        with self.assertNoMessages():
            self.checker._check_keyword_parentheses(_tokenize_str(code), offset)

    def testPositiveSuperfluousParensWalrusOperatorIf(self):
        """Test positive superfluous parens with the walrus operator"""
        code = "if ((odd := is_odd(i))):"
        msg = Message("superfluous-parens", line=1, args="if")
        with self.assertAddsMessages(msg):
            self.checker._check_keyword_parentheses(_tokenize_str(code), 0)

    def testNoSuperfluousParensWalrusOperatorNot(self):
        """Test superfluous-parens with the not operator"""
        code = "not (foo := 5)"
        with self.assertNoMessages():
            self.checker._check_keyword_parentheses(_tokenize_str(code), 0)

    def testCheckIfArgsAreNotUnicode(self):
        cases = [("if (foo):", 0), ("assert (1 == 1)", 0)]

        for code, offset in cases:
            self.checker._check_keyword_parentheses(_tokenize_str(code), offset)
            got = self.linter.release_messages()
            assert isinstance(got[-1].args, str)

    def testFuturePrintStatementWithoutParensWarning(self):
        code = """from __future__ import print_function
print('Hello world!')
"""
        tree = astroid.parse(code)
        with self.assertNoMessages():
            self.checker.process_module(tree)
            self.checker.process_tokens(_tokenize_str(code))

    def testKeywordParensFalsePositive(self):
        code = "if 'bar' in (DICT or {}):"
        with self.assertNoMessages():
            self.checker._check_keyword_parentheses(_tokenize_str(code), start=2)


class TestCheckSpace(CheckerTestCase):
    CHECKER_CLASS = FormatChecker

    def test_encoding_token(self):
        """Make sure the encoding token doesn't change the checker's behavior

        _tokenize_str doesn't produce an encoding token, but
        reading a file does
        """
        with self.assertNoMessages():
            encoding_token = tokenize.TokenInfo(
                tokenize.ENCODING, "utf-8", (0, 0), (0, 0), ""
            )
            tokens = [encoding_token] + _tokenize_str(
                "if (\n        None):\n    pass\n"
            )
            self.checker.process_tokens(tokens)


def test_disable_global_option_end_of_line():
    """
    Test for issue with disabling tokenizer messages
    that extend beyond the scope of the ast tokens
    """
    file_ = tempfile.NamedTemporaryFile("w", delete=False)
    with file_:
        file_.write(
            """
mylist = [
    None
        ]
    """
        )
    try:
        linter = lint.PyLinter()
        checker = FormatChecker(linter)
        linter.register_checker(checker)
        args = linter.load_command_line_configuration(
            [file_.name, "-d", "bad-continuation"]
        )
        myreporter = reporters.CollectingReporter()
        linter.set_reporter(myreporter)
        linter.check(args)
        assert not myreporter.messages
    finally:
        os.remove(file_.name)