Merge pull request #1720 from PyCQA/remove-diff

remove --diff option

docs/source/internal/utils.rst

@@ -66,11 +66,3 @@ The standard library's :func:`fnmatch.fnmatch` is excellent at deciding if a
 filename matches a single pattern. In our use case, however, we typically have
 a list of patterns and want to know if the filename matches any of them. This
 function abstracts that logic away with a little extra logic.
-
-.. autofunction:: flake8.utils.parse_unified_diff
-
-To handle usage of :option:`flake8 --diff`, |Flake8| needs to be able
-to parse the name of the files in the diff as well as the ranges indicated the
-sections that have been changed. This function either accepts the diff as an
-argument or reads the diff from standard-in. It then returns a dictionary with
-filenames as the keys and sets of line numbers as the value.

docs/source/user/options.rst

@@ -44,8 +44,6 @@ Index of Options
 
 - :option:`flake8 --count`
 
-- :option:`flake8 --diff`
-
 - :option:`flake8 --exclude`
 
 - :option:`flake8 --filename`
@@ -230,27 +228,6 @@ Options and their Descriptions
         count = True
 
 
-.. option:: --diff
-
-    :ref:`Go back to index <top>`
-
-    .. warning::
-
-        Due to hiding potential errors, this option is deprecated and will be
-        removed in a future version.
-
-    Use the unified diff provided on standard in to only check the modified
-    files and report errors included in the diff.
-
-    Command-line example:
-
-    .. prompt:: bash
-
-        git diff -u | flake8 --diff
-
-    This **can not** be specified in config files.
-
-
 .. option:: --exclude=<patterns>
 
     :ref:`Go back to index <top>`

src/flake8/api/legacy.py

@@ -136,7 +136,6 @@ def excluded(path: str) -> bool:
                     stdin_display_name=self.options.stdin_display_name,
                     filename_patterns=self.options.filename,
                     exclude=self.options.exclude,
-                    is_running_from_diff=self.options.diff,
                 )
             )
             return not paths

src/flake8/checker.py

@@ -97,8 +97,6 @@ def _job_count(self) -> int:
         #   implementation issues
         # - the user provided stdin and that's not something we can handle
         #   well
-        # - we're processing a diff, which again does not work well with
-        #   multiprocessing and which really shouldn't require multiprocessing
         # - the user provided some awful input
 
         # class state is only preserved when using the `fork` strategy.
@@ -116,13 +114,6 @@ def _job_count(self) -> int:
             )
             return 0
 
-        if self.options.diff:
-            LOG.warning(
-                "The --diff option was specified with --jobs but "
-                "they are not compatible. Ignoring --jobs arguments."
-            )
-            return 0
-
         jobs = self.options.jobs
 
         # If the value is "auto", we want to let the multiprocessing library
@@ -169,7 +160,6 @@ def make_checkers(self, paths: list[str] | None = None) -> None:
                 stdin_display_name=self.options.stdin_display_name,
                 filename_patterns=self.options.filename,
                 exclude=self.exclude,
-                is_running_from_diff=self.options.diff,
             )
         ]
         self.checkers = [c for c in self._all_checkers if c.should_process]

src/flake8/discover_files.py

@@ -55,7 +55,6 @@ def expand_paths(
     stdin_display_name: str,
     filename_patterns: Sequence[str],
     exclude: Sequence[str],
-    is_running_from_diff: bool,
 ) -> Generator[str, None, None]:
     """Expand out ``paths`` from commandline to the lintable files."""
     if not paths:
@@ -75,24 +74,16 @@ def is_excluded(arg: str) -> bool:
             logger=LOG,
         )
 
-    def is_included(arg: str, fname: str) -> bool:
-        # while running from a diff, the arguments aren't _explicitly_
-        # listed so we still filter them
-        if is_running_from_diff:
-            return utils.fnmatch(fname, filename_patterns)
-        else:
-            return (
-                # always lint `-`
-                fname == "-"
-                # always lint explicitly passed (even if not matching filter)
-                or arg == fname
-                # otherwise, check the file against filtered patterns
-                or utils.fnmatch(fname, filename_patterns)
-            )
-
     return (
         filename
         for path in paths
         for filename in _filenames_from(path, predicate=is_excluded)
-        if is_included(path, filename)
+        if (
+            # always lint `-`
+            filename == "-"
+            # always lint explicitly passed (even if not matching filter)
+            or path == filename
+            # otherwise, check the file against filtered patterns
+            or utils.fnmatch(filename, filename_patterns)
+        )
     )

src/flake8/main/application.py

@@ -13,7 +13,6 @@
 from flake8 import defaults
 from flake8 import exceptions
 from flake8 import style_guide
-from flake8 import utils
 from flake8.formatting.base import BaseFormatter
 from flake8.main import debug
 from flake8.main import options
@@ -66,9 +65,6 @@ def __init__(self) -> None:
         #: with a non-zero status code
         self.catastrophic_failure = False
 
-        #: The parsed diff information
-        self.parsed_diff: dict[str, set[int]] = {}
-
     def parse_preliminary_options(
         self, argv: Sequence[str]
     ) -> tuple[argparse.Namespace, list[str]]:
@@ -158,13 +154,6 @@ def parse_configuration_and_cli(
             print(json.dumps(info, indent=2, sort_keys=True))
             raise SystemExit(0)
 
-        if self.options.diff:
-            LOG.warning(
-                "the --diff option is deprecated and will be removed in a "
-                "future version."
-            )
-            self.parsed_diff = utils.parse_unified_diff()
-
         for loaded in self.plugins.all_plugins():
             parse_options = getattr(loaded.obj, "parse_options", None)
             if parse_options is None:
@@ -194,9 +183,6 @@ def make_guide(self) -> None:
             self.options, self.formatter
         )
 
-        if self.options.diff:
-            self.guide.add_diff_ranges(self.parsed_diff)
-
     def make_file_checker_manager(self) -> None:
         """Initialize our FileChecker Manager."""
         assert self.guide is not None
@@ -213,16 +199,9 @@ def run_checks(self) -> None:
         :class:`~flake8.checker.Manger` instance run the checks it is
         managing.
         """
-        assert self.options is not None
         assert self.file_checker_manager is not None
-        if self.options.diff:
-            files: list[str] | None = sorted(self.parsed_diff)
-            if not files:
-                return
-        else:
-            files = None
 
-        self.file_checker_manager.start(files)
+        self.file_checker_manager.start()
         try:
             self.file_checker_manager.run()
         except exceptions.PluginExecutionFailed as plugin_failed:

src/flake8/main/options.py

@@ -114,7 +114,6 @@ def register_default_options(option_manager: OptionManager) -> None:
     - ``-q``/``--quiet``
     - ``--color``
     - ``--count``
-    - ``--diff``
     - ``--exclude``
     - ``--extend-exclude``
     - ``--filename``
@@ -163,13 +162,6 @@ def register_default_options(option_manager: OptionManager) -> None:
         "all other output.",
     )
 
-    add_option(
-        "--diff",
-        action="store_true",
-        help="(DEPRECATED) Report changes only within line number ranges in "
-        "the unified diff provided on standard in by the user.",
-    )
-
     add_option(
         "--exclude",
         metavar="patterns",

src/flake8/style_guide.py

@@ -298,18 +298,6 @@ def handle_error(
             code, filename, line_number, column_number, text, physical_line
         )
 
-    def add_diff_ranges(self, diffinfo: dict[str, set[int]]) -> None:
-        """Update the StyleGuides to filter out information not in the diff.
-
-        This provides information to the underlying StyleGuides so that only
-        the errors in the line number ranges are reported.
-
-        :param diffinfo:
-            Dictionary mapping filenames to sets of line number ranges.
-        """
-        for guide in self.style_guides:
-            guide.add_diff_ranges(diffinfo)
-
 
 class StyleGuide:
     """Manage a Flake8 user's style guide."""
@@ -333,7 +321,6 @@ def __init__(
         self.filename = filename
         if self.filename:
             self.filename = utils.normalize_path(self.filename)
-        self._parsed_diff: dict[str, set[int]] = {}
 
     def __repr__(self) -> str:
         """Make it easier to debug which StyleGuide we're using."""
@@ -440,20 +427,8 @@ def handle_error(
             self.should_report_error(error.code) is Decision.Selected
         )
         is_not_inline_ignored = error.is_inline_ignored(disable_noqa) is False
-        is_included_in_diff = error.is_in(self._parsed_diff)
-        if error_is_selected and is_not_inline_ignored and is_included_in_diff:
+        if error_is_selected and is_not_inline_ignored:
             self.formatter.handle(error)
             self.stats.record(error)
             return 1
         return 0
-
-    def add_diff_ranges(self, diffinfo: dict[str, set[int]]) -> None:
-        """Update the StyleGuide to filter out information not in the diff.
-
-        This provides information to the StyleGuide so that only the errors
-        in the line number ranges are reported.
-
-        :param diffinfo:
-            Dictionary mapping filenames to sets of line number ranges.
-        """
-        self._parsed_diff = diffinfo

src/flake8/utils.py

@@ -1,7 +1,6 @@
 """Utility methods for flake8."""
 from __future__ import annotations
 
-import collections
 import fnmatch as _fnmatch
 import functools
 import io
@@ -18,7 +17,6 @@
 
 from flake8 import exceptions
 
-DIFF_HUNK_REGEXP = re.compile(r"^@@ -\d+(?:,\d+)? \+(\d+)(?:,(\d+))? @@.*$")
 COMMA_SEPARATED_LIST_RE = re.compile(r"[,\s]")
 LOCAL_PLUGIN_LIST_RE = re.compile(r"[,\t\n\r\f\v]")
 NORMALIZE_PACKAGE_NAME_RE = re.compile(r"[-_.]+")
@@ -202,71 +200,6 @@ def stdin_get_lines() -> list[str]:
     return list(io.StringIO(stdin_get_value()))
 
 
-def parse_unified_diff(diff: str | None = None) -> dict[str, set[int]]:
-    """Parse the unified diff passed on stdin.
-
-    :returns:
-        dictionary mapping file names to sets of line numbers
-    """
-    # Allow us to not have to patch out stdin_get_value
-    if diff is None:
-        diff = stdin_get_value()
-
-    number_of_rows = None
-    current_path = None
-    parsed_paths: dict[str, set[int]] = collections.defaultdict(set)
-    for line in diff.splitlines():
-        if number_of_rows:
-            if not line or line[0] != "-":
-                number_of_rows -= 1
-            # We're in the part of the diff that has lines starting with +, -,
-            # and ' ' to show context and the changes made. We skip these
-            # because the information we care about is the filename and the
-            # range within it.
-            # When number_of_rows reaches 0, we will once again start
-            # searching for filenames and ranges.
-            continue
-
-        # NOTE(sigmavirus24): Diffs that we support look roughly like:
-        #    diff a/file.py b/file.py
-        #    ...
-        #    --- a/file.py
-        #    +++ b/file.py
-        # Below we're looking for that last line. Every diff tool that
-        # gives us this output may have additional information after
-        # ``b/file.py`` which it will separate with a \t, e.g.,
-        #    +++ b/file.py\t100644
-        # Which is an example that has the new file permissions/mode.
-        # In this case we only care about the file name.
-        if line[:3] == "+++":
-            current_path = line[4:].split("\t", 1)[0]
-            # NOTE(sigmavirus24): This check is for diff output from git.
-            if current_path[:2] == "b/":
-                current_path = current_path[2:]
-            # We don't need to do anything else. We have set up our local
-            # ``current_path`` variable. We can skip the rest of this loop.
-            # The next line we will see will give us the hung information
-            # which is in the next section of logic.
-            continue
-
-        hunk_match = DIFF_HUNK_REGEXP.match(line)
-        # NOTE(sigmavirus24): pep8/pycodestyle check for:
-        #    line[:3] == '@@ '
-        # But the DIFF_HUNK_REGEXP enforces that the line start with that
-        # So we can more simply check for a match instead of slicing and
-        # comparing.
-        if hunk_match:
-            (row, number_of_rows) = (
-                1 if not group else int(group) for group in hunk_match.groups()
-            )
-            assert current_path is not None
-            parsed_paths[current_path].update(range(row, row + number_of_rows))
-
-    # We have now parsed our diff into a dictionary that looks like:
-    #    {'file.py': set(range(10, 16), range(18, 20)), ...}
-    return parsed_paths
-
-
 def is_using_stdin(paths: list[str]) -> bool:
     """Determine if we're going to read from stdin.
 

src/flake8/violation.py

@@ -67,36 +67,3 @@ def is_inline_ignored(self, disable_noqa: bool) -> bool:
             "%r is not ignored inline with ``# noqa: %s``", self, codes_str
         )
         return False
-
-    def is_in(self, diff: dict[str, set[int]]) -> bool:
-        """Determine if the violation is included in a diff's line ranges.
-
-        This function relies on the parsed data added via
-        :meth:`~StyleGuide.add_diff_ranges`. If that has not been called and
-        we are not evaluating files in a diff, then this will always return
-        True. If there are diff ranges, then this will return True if the
-        line number in the error falls inside one of the ranges for the file
-        (and assuming the file is part of the diff data). If there are diff
-        ranges, this will return False if the file is not part of the diff
-        data or the line number of the error is not in any of the ranges of
-        the diff.
-
-        :returns:
-            True if there is no diff or if the error is in the diff's line
-            number ranges. False if the error's line number falls outside
-            the diff's line number ranges.
-        """
-        if not diff:
-            return True
-
-        # NOTE(sigmavirus24): The parsed diff will be a defaultdict with
-        # a set as the default value (if we have received it from
-        # flake8.utils.parse_unified_diff). In that case ranges below
-        # could be an empty set (which is False-y) or if someone else
-        # is using this API, it could be None. If we could guarantee one
-        # or the other, we would check for it more explicitly.
-        line_numbers = diff.get(self.filename)
-        if not line_numbers:
-            return False
-
-        return self.line_number in line_numbers