python_fmt_integration_test.py

# Copyright 2020 Pants project contributors (see CONTRIBUTORS.md).
# Licensed under the Apache License, Version 2.0 (see LICENSE).

from typing import List, Optional

from pants.backend.python.lint.black.rules import BlackRequest
from pants.backend.python.lint.black.rules import rules as black_rules
from pants.backend.python.lint.isort.rules import IsortRequest
from pants.backend.python.lint.isort.rules import rules as isort_rules
from pants.backend.python.lint.python_fmt import PythonFmtTargets, format_python_target
from pants.backend.python.target_types import PythonLibrary
from pants.core.goals.fmt import LanguageFmtResults
from pants.engine.addresses import Address
from pants.engine.fs import CreateDigest, Digest, FileContent
from pants.engine.rules import RootRule
from pants.engine.target import Targets
from pants.testutil.engine_util import Params
from pants.testutil.external_tool_test_base import ExternalToolTestBase
from pants.testutil.option_util import create_options_bootstrapper


class PythonFmtIntegrationTest(ExternalToolTestBase):
    @classmethod
    def rules(cls):
        return (
            *super().rules(),
            format_python_target,
            *black_rules(),
            *isort_rules(),
            RootRule(PythonFmtTargets),
            RootRule(BlackRequest),
            RootRule(IsortRequest),
        )

    def run_black_and_isort(
        self, source_files: List[FileContent], *, name: str, extra_args: Optional[List[str]] = None
    ) -> LanguageFmtResults:
        for source_file in source_files:
            self.create_file(source_file.path, source_file.content.decode())
        targets = PythonFmtTargets(
            Targets([PythonLibrary({}, address=Address.parse(f"test:{name}"))])
        )
        args = [
            "--backend-packages=['pants.backend.python.lint.black', 'pants.backend.python.lint.isort']",
            *(extra_args or []),
        ]
        results = self.request_product(
            LanguageFmtResults, Params(targets, create_options_bootstrapper(args=args)),
        )
        return results

    def get_digest(self, source_files: List[FileContent]) -> Digest:
        return self.request_product(Digest, CreateDigest(source_files))

    def test_multiple_formatters_changing_the_same_file(self) -> None:
        original_source = FileContent(
            "test/target.py", content=b"from animals import dog, cat\n\nprint('hello')\n",
        )
        fixed_source = FileContent(
            "test/target.py", content=b'from animals import cat, dog\n\nprint("hello")\n',
        )
        results = self.run_black_and_isort([original_source], name="same_file")
        assert results.output == self.get_digest([fixed_source])
        assert results.did_change is True

    def test_multiple_formatters_changing_different_files(self) -> None:
        original_sources = [
            FileContent("test/isort.py", content=b"from animals import dog, cat\n"),
            FileContent("test/black.py", content=b"print('hello')\n"),
        ]
        fixed_sources = [
            FileContent("test/isort.py", content=b"from animals import cat, dog\n"),
            FileContent("test/black.py", content=b'print("hello")\n'),
        ]
        results = self.run_black_and_isort(original_sources, name="different_file")
        assert results.output == self.get_digest(fixed_sources)
        assert results.did_change is True

    def test_skipped_formatter(self) -> None:
        """Ensure that a skipped formatter does not interfere with other formatters."""
        original_source = FileContent(
            "test/skipped.py", content=b"from animals import dog, cat\n\nprint('hello')\n",
        )
        fixed_source = FileContent(
            "test/skipped.py", content=b"from animals import cat, dog\n\nprint('hello')\n",
        )
        results = self.run_black_and_isort(
            [original_source], name="skipped", extra_args=["--black-skip"]
        )
        assert results.output == self.get_digest([fixed_source])
        assert results.did_change is True

    def test_no_changes(self) -> None:
        source = FileContent(
            "test/target.py", content=b'from animals import cat, dog\n\nprint("hello")\n',
        )
        results = self.run_black_and_isort([source], name="different_file")
        assert results.output == self.get_digest([source])
        assert results.did_change is False