Method setup

mypy/test/data.py:349–383

(self)

            raise

    def setup(self) -> None:
        parse_test_case(case=self)
        self.old_cwd = os.getcwd()
        self.tmpdir = tempfile.mkdtemp(prefix="mypy-test-")
        os.chdir(self.tmpdir)
        os.mkdir(test_temp_dir)

        # Precalculate steps for find_steps()
        steps: dict[int, list[FileOperation]] = {}

        for path, content in self.files:
            m = re.match(r".*\.([0-9]+)$", path)
            if m:
                # Skip writing subsequent incremental steps - rather
                # store them as operations.
                num = int(m.group(1))
                assert num >= 2
                target_path = re.sub(r"\.[0-9]+$", "", path)
                module = module_from_path(target_path)
                operation = UpdateFile(module, content, target_path)
                steps.setdefault(num, []).append(operation)
            else:
                # Write the first incremental steps
                dir = os.path.dirname(path)
                os.makedirs(dir, exist_ok=True)
                with open(path, "w", encoding="utf8") as f:
                    f.write(content)

        for num, paths in self.deleted_paths.items():
            assert num >= 2
            for path in paths:
                module = module_from_path(path)
                steps.setdefault(num, []).append(DeleteFile(module, path))
        max_step = max(steps) if steps else 2
        self.steps = [steps.get(num, []) for num in range(2, max_step + 1)]

    def teardown(self) -> None:
        if self.old_cwd is not None: