Provide a stdin-filename to allow stdin to respect force-exclude rules (#1780)

* Provide a stdin-filename to allow stdin to respect exclude/force-exclude rules

This will allow automatic tools to enforce the project's
exclude/force-exclude rules even if they pass the file through stdin to
update its buffer.

This is a similar solution to --stdin-display-name in flake8.

* Update src/black/__init__.py

Co-authored-by: Richard Si <63936253+ichard26@users.noreply.github.com>
* --stdin-filename should only respect --exclude-filename

* Update README with the new --stdin-filename option

* Write some tests for the new stdin-filename functionality

* Apply suggestions from code review

Co-authored-by: Hugo van Kemenade <hugovk@users.noreply.github.com>
* Force stdin output when we asked for stdin even if the file exists

* Add an entry in the changelog regarding --stdin-filename

* Reduce disk reads if possible

Co-authored-by: Richard Si <63936253+ichard26@users.noreply.github.com>
* Check for is_stdin and p.is_file before checking for p.is_dir()

Co-authored-by: Richard Si <63936253+ichard26@users.noreply.github.com>
Co-authored-by: Hugo van Kemenade <hugovk@users.noreply.github.com>

diff --git a/README.md b/README.md
index d34ce146e0d5ad8531813b257e037280b4441e49..a557a6fc6c8fd9628ca2ebdb668ca5622e819361 100644 (file)
--- a/README.md
+++ b/README.md
@@ -135,6 +135,11 @@ Options:
                                   matching this regex will be excluded even
                                   when they are passed explicitly as arguments.
 
+  --stdin-filename TEXT           The name of the file when passing it through
+                                  stdin. Useful to make sure Black will respect
+                                  --force-exclude option on some editors that
+                                  rely on using stdin.
+
   -q, --quiet                     Don't emit non-error messages to stderr.
                                   Errors are still emitted; silence those with
                                   2>/dev/null.

diff --git a/docs/change_log.md b/docs/change_log.md
index 1ee35a4d8f99ef40f06e2319492cc7f8fbe03203..e6afefbf6864db875ff8ca8dd59ea75b17b8f8ca 100644 (file)
--- a/docs/change_log.md
+++ b/docs/change_log.md
@@ -23,6 +23,9 @@
 
 - Added support for PEP 614 relaxed decorator syntax on python 3.9 (#1711)
 
+- Added `--stdin-filename` argument to allow stdin to respect `--force-exclude` rules.
+  Works very alike to flake8's `--stdin-display-name` (#1780)
+
 ### 20.8b1
 
 #### _Packaging_

diff --git a/src/black/__init__.py b/src/black/__init__.py
index 44edeb0d9f1a0c09d4be1e2aee383a677d59f821..48690573810373ae94123839474c29ea772e9630 100644 (file)
--- a/src/black/__init__.py
+++ b/src/black/__init__.py
@@ -68,6 +68,7 @@ DEFAULT_LINE_LENGTH = 88
 DEFAULT_EXCLUDES = r"/(\.direnv|\.eggs|\.git|\.hg|\.mypy_cache|\.nox|\.tox|\.venv|\.svn|_build|buck-out|build|dist)/"  # noqa: B950
 DEFAULT_INCLUDES = r"\.pyi?$"
 CACHE_DIR = Path(user_cache_dir("black", version=__version__))
+STDIN_PLACEHOLDER = "__BLACK_STDIN_FILENAME__"
 
 STRING_PREFIX_CHARS: Final = "furbFURB"  # All possible string prefix characters.
 
@@ -457,6 +458,15 @@ def target_version_option_callback(
         "excluded even when they are passed explicitly as arguments."
     ),
 )
+@click.option(
+    "--stdin-filename",
+    type=str,
+    help=(
+        "The name of the file when passing it through stdin. Useful to make "
+        "sure Black will respect --force-exclude option on some "
+        "editors that rely on using stdin."
+    ),
+)
 @click.option(
     "-q",
     "--quiet",
@@ -516,6 +526,7 @@ def main(
     include: str,
     exclude: str,
     force_exclude: Optional[str],
+    stdin_filename: Optional[str],
     src: Tuple[str, ...],
     config: Optional[str],
 ) -> None:
@@ -548,6 +559,7 @@ def main(
         exclude=exclude,
         force_exclude=force_exclude,
         report=report,
+        stdin_filename=stdin_filename,
     )
 
     path_empty(
@@ -587,6 +599,7 @@ def get_sources(
     exclude: str,
     force_exclude: Optional[str],
     report: "Report",
+    stdin_filename: Optional[str],
 ) -> Set[Path]:
     """Compute the set of files to be formatted."""
     try:
@@ -613,22 +626,14 @@ def get_sources(
     gitignore = get_gitignore(root)
 
     for s in src:
-        p = Path(s)
-        if p.is_dir():
-            sources.update(
-                gen_python_files(
-                    p.iterdir(),
-                    root,
-                    include_regex,
-                    exclude_regex,
-                    force_exclude_regex,
-                    report,
-                    gitignore,
-                )
-            )
-        elif s == "-":
-            sources.add(p)
-        elif p.is_file():
+        if s == "-" and stdin_filename:
+            p = Path(stdin_filename)
+            is_stdin = True
+        else:
+            p = Path(s)
+            is_stdin = False
+
+        if is_stdin or p.is_file():
             normalized_path = normalize_path_maybe_ignore(p, root, report)
             if normalized_path is None:
                 continue
@@ -643,6 +648,23 @@ def get_sources(
                 report.path_ignored(p, "matches the --force-exclude regular expression")
                 continue
 
+            if is_stdin:
+                p = Path(f"{STDIN_PLACEHOLDER}{str(p)}")
+
+            sources.add(p)
+        elif p.is_dir():
+            sources.update(
+                gen_python_files(
+                    p.iterdir(),
+                    root,
+                    include_regex,
+                    exclude_regex,
+                    force_exclude_regex,
+                    report,
+                    gitignore,
+                )
+            )
+        elif s == "-":
             sources.add(p)
         else:
             err(f"invalid path: {s}")
@@ -670,7 +692,18 @@ def reformat_one(
     """
     try:
         changed = Changed.NO
-        if not src.is_file() and str(src) == "-":
+
+        if str(src) == "-":
+            is_stdin = True
+        elif str(src).startswith(STDIN_PLACEHOLDER):
+            is_stdin = True
+            # Use the original name again in case we want to print something
+            # to the user
+            src = Path(str(src)[len(STDIN_PLACEHOLDER) :])
+        else:
+            is_stdin = False
+
+        if is_stdin:
             if format_stdin_to_stdout(fast=fast, write_back=write_back, mode=mode):
                 changed = Changed.YES
         else:

diff --git a/tests/test_black.py b/tests/test_black.py
index b0cf6ed5caa490ed4f9af71c24e451dedc24d071..a688c8780efe682530d11ccf55c9995eea8608a8 100644 (file)
--- a/tests/test_black.py
+++ b/tests/test_black.py
@@ -1336,10 +1336,169 @@ class BlackTestCase(BlackBaseTestCase):
                 exclude=exclude,
                 force_exclude=None,
                 report=report,
+                stdin_filename=None,
             )
         )
         self.assertEqual(sorted(expected), sorted(sources))
 
+    @patch("black.find_project_root", lambda *args: THIS_DIR.resolve())
+    def test_get_sources_with_stdin(self) -> None:
+        include = ""
+        exclude = r"/exclude/|a\.py"
+        src = "-"
+        report = black.Report()
+        expected = [Path("-")]
+        sources = list(
+            black.get_sources(
+                ctx=FakeContext(),
+                src=(src,),
+                quiet=True,
+                verbose=False,
+                include=include,
+                exclude=exclude,
+                force_exclude=None,
+                report=report,
+                stdin_filename=None,
+            )
+        )
+        self.assertEqual(sorted(expected), sorted(sources))
+
+    @patch("black.find_project_root", lambda *args: THIS_DIR.resolve())
+    def test_get_sources_with_stdin_filename(self) -> None:
+        include = ""
+        exclude = r"/exclude/|a\.py"
+        src = "-"
+        report = black.Report()
+        stdin_filename = str(THIS_DIR / "data/collections.py")
+        expected = [Path(f"__BLACK_STDIN_FILENAME__{stdin_filename}")]
+        sources = list(
+            black.get_sources(
+                ctx=FakeContext(),
+                src=(src,),
+                quiet=True,
+                verbose=False,
+                include=include,
+                exclude=exclude,
+                force_exclude=None,
+                report=report,
+                stdin_filename=stdin_filename,
+            )
+        )
+        self.assertEqual(sorted(expected), sorted(sources))
+
+    @patch("black.find_project_root", lambda *args: THIS_DIR.resolve())
+    def test_get_sources_with_stdin_filename_and_exclude(self) -> None:
+        # Exclude shouldn't exclude stdin_filename since it is mimicing the
+        # file being passed directly. This is the same as
+        # test_exclude_for_issue_1572
+        path = THIS_DIR / "data" / "include_exclude_tests"
+        include = ""
+        exclude = r"/exclude/|a\.py"
+        src = "-"
+        report = black.Report()
+        stdin_filename = str(path / "b/exclude/a.py")
+        expected = [Path(f"__BLACK_STDIN_FILENAME__{stdin_filename}")]
+        sources = list(
+            black.get_sources(
+                ctx=FakeContext(),
+                src=(src,),
+                quiet=True,
+                verbose=False,
+                include=include,
+                exclude=exclude,
+                force_exclude=None,
+                report=report,
+                stdin_filename=stdin_filename,
+            )
+        )
+        self.assertEqual(sorted(expected), sorted(sources))
+
+    @patch("black.find_project_root", lambda *args: THIS_DIR.resolve())
+    def test_get_sources_with_stdin_filename_and_force_exclude(self) -> None:
+        # Force exclude should exclude the file when passing it through
+        # stdin_filename
+        path = THIS_DIR / "data" / "include_exclude_tests"
+        include = ""
+        force_exclude = r"/exclude/|a\.py"
+        src = "-"
+        report = black.Report()
+        stdin_filename = str(path / "b/exclude/a.py")
+        sources = list(
+            black.get_sources(
+                ctx=FakeContext(),
+                src=(src,),
+                quiet=True,
+                verbose=False,
+                include=include,
+                exclude="",
+                force_exclude=force_exclude,
+                report=report,
+                stdin_filename=stdin_filename,
+            )
+        )
+        self.assertEqual([], sorted(sources))
+
+    def test_reformat_one_with_stdin(self) -> None:
+        with patch(
+            "black.format_stdin_to_stdout",
+            return_value=lambda *args, **kwargs: black.Changed.YES,
+        ) as fsts:
+            report = MagicMock()
+            path = Path("-")
+            black.reformat_one(
+                path,
+                fast=True,
+                write_back=black.WriteBack.YES,
+                mode=DEFAULT_MODE,
+                report=report,
+            )
+            fsts.assert_called_once()
+            report.done.assert_called_with(path, black.Changed.YES)
+
+    def test_reformat_one_with_stdin_filename(self) -> None:
+        with patch(
+            "black.format_stdin_to_stdout",
+            return_value=lambda *args, **kwargs: black.Changed.YES,
+        ) as fsts:
+            report = MagicMock()
+            p = "foo.py"
+            path = Path(f"__BLACK_STDIN_FILENAME__{p}")
+            expected = Path(p)
+            black.reformat_one(
+                path,
+                fast=True,
+                write_back=black.WriteBack.YES,
+                mode=DEFAULT_MODE,
+                report=report,
+            )
+            fsts.assert_called_once()
+            # __BLACK_STDIN_FILENAME__ should have been striped
+            report.done.assert_called_with(expected, black.Changed.YES)
+
+    def test_reformat_one_with_stdin_and_existing_path(self) -> None:
+        with patch(
+            "black.format_stdin_to_stdout",
+            return_value=lambda *args, **kwargs: black.Changed.YES,
+        ) as fsts:
+            report = MagicMock()
+            # Even with an existing file, since we are forcing stdin, black
+            # should output to stdout and not modify the file inplace
+            p = Path(str(THIS_DIR / "data/collections.py"))
+            # Make sure is_file actually returns True
+            self.assertTrue(p.is_file())
+            path = Path(f"__BLACK_STDIN_FILENAME__{p}")
+            expected = Path(p)
+            black.reformat_one(
+                path,
+                fast=True,
+                write_back=black.WriteBack.YES,
+                mode=DEFAULT_MODE,
+                report=report,
+            )
+            fsts.assert_called_once()
+            # __BLACK_STDIN_FILENAME__ should have been striped
+            report.done.assert_called_with(expected, black.Changed.YES)
+
     def test_gitignore_exclude(self) -> None:
         path = THIS_DIR / "data" / "include_exclude_tests"
         include = re.compile(r"\.pyi?$")