Add --verbose and report excluded paths in it, too

Fixes #283

README.md

@@ -99,6 +99,9 @@ Options:
   -q, --quiet                 Don't emit non-error messages to stderr. Errors
                               are still emitted, silence those with
                               2>/dev/null.
+  -v, --verbose               Also emit messages to stderr about files
+                              that were not changed or were ignored due to
+                              --exclude=.
   --version                   Show the version and exit.
   --help                      Show this message and exit.
 ```
@@ -712,6 +715,8 @@ More details can be found in [CONTRIBUTING](CONTRIBUTING.md).
 
 * added `--skip-string-normalization` (#118)
 
+* added `--verbose` (#283)
+
 * fixed stdin handling not working correctly if an old version of Click was
   used (#276)
 

black.py

@@ -238,6 +238,15 @@ def from_configuration(
         "silence those with 2>/dev/null."
     ),
 )
+@click.option(
+    "-v",
+    "--verbose",
+    is_flag=True,
+    help=(
+        "Also emit messages to stderr about files that were not changed or were "
+        "ignored due to --exclude=."
+    ),
+)
 @click.version_option(version=__version__)
 @click.argument(
     "src",
@@ -257,6 +266,7 @@ def main(
     py36: bool,
     skip_string_normalization: bool,
     quiet: bool,
+    verbose: bool,
     include: str,
     exclude: str,
     src: List[str],
@@ -266,7 +276,7 @@ def main(
     mode = FileMode.from_configuration(
         py36=py36, pyi=pyi, skip_string_normalization=skip_string_normalization
     )
-    report = Report(check=check, quiet=quiet)
+    report = Report(check=check, quiet=quiet, verbose=verbose)
     sources: List[Path] = []
     try:
         include_regex = re.compile(include)
@@ -283,7 +293,7 @@ def main(
         p = Path(s)
         if p.is_dir():
             sources.extend(
-                gen_python_files_in_dir(p, root, include_regex, exclude_regex)
+                gen_python_files_in_dir(p, root, include_regex, exclude_regex, report)
             )
         elif p.is_file() or s == "-":
             # if a file was explicitly given, we don't care about its extension
@@ -2803,10 +2813,16 @@ def get_future_imports(node: Node) -> Set[str]:
 
 
 def gen_python_files_in_dir(
-    path: Path, root: Path, include: Pattern[str], exclude: Pattern[str]
+    path: Path,
+    root: Path,
+    include: Pattern[str],
+    exclude: Pattern[str],
+    report: "Report",
 ) -> Iterator[Path]:
     """Generate all files under `path` whose paths are not excluded by the
     `exclude` regex, but are included by the `include` regex.
+
+    `report` is where output about exclusions goes.
     """
     assert root.is_absolute(), f"INTERNAL ERROR: `root` must be absolute but is {root}"
     for child in path.iterdir():
@@ -2815,10 +2831,11 @@ def gen_python_files_in_dir(
             normalized_path += "/"
         exclude_match = exclude.search(normalized_path)
         if exclude_match and exclude_match.group(0):
+            report.path_ignored(child, f"matches --exclude={exclude.pattern}")
             continue
 
         if child.is_dir():
-            yield from gen_python_files_in_dir(child, root, include, exclude)
+            yield from gen_python_files_in_dir(child, root, include, exclude, report)
 
         elif child.is_file():
             include_match = include.search(normalized_path)
@@ -2861,6 +2878,7 @@ class Report:
 
     check: bool = False
     quiet: bool = False
+    verbose: bool = False
     change_count: int = 0
     same_count: int = 0
     failure_count: int = 0
@@ -2869,11 +2887,11 @@ def done(self, src: Path, changed: Changed) -> None:
         """Increment the counter for successful reformatting. Write out a message."""
         if changed is Changed.YES:
             reformatted = "would reformat" if self.check else "reformatted"
-            if not self.quiet:
+            if self.verbose or not self.quiet:
                 out(f"{reformatted} {src}")
             self.change_count += 1
         else:
-            if not self.quiet:
+            if self.verbose:
                 if changed is Changed.NO:
                     msg = f"{src} already well formatted, good job."
                 else:
@@ -2886,6 +2904,10 @@ def failed(self, src: Path, message: str) -> None:
         err(f"error: cannot format {src}: {message}")
         self.failure_count += 1
 
+    def path_ignored(self, path: Path, message: str) -> None:
+        if self.verbose:
+            out(f"{path} ignored: {message}", bold=False)
+
     @property
     def return_code(self) -> int:
         """Return the exit code that the app should use.

tests/test_black.py

@@ -378,8 +378,8 @@ def test_new_line_between_class_and_code(self) -> None:
         black.assert_equivalent(source, actual)
         black.assert_stable(source, actual, line_length=ll)
 
-    def test_report(self) -> None:
+    def test_report_verbose(self) -> None:
-        report = black.Report()
+        report = black.Report(verbose=True)
         out_lines = []
         err_lines = []
 
@@ -446,9 +446,19 @@ def err(msg: str, **kwargs: Any) -> None:
                 "2 files failed to reformat.",
             )
             self.assertEqual(report.return_code, 123)
-            report.done(Path("f4"), black.Changed.NO)
+            report.path_ignored(Path("wat"), "no match")
             self.assertEqual(len(out_lines), 5)
             self.assertEqual(len(err_lines), 2)
+            self.assertEqual(out_lines[-1], "wat ignored: no match")
+            self.assertEqual(
+                unstyle(str(report)),
+                "2 files reformatted, 2 files left unchanged, "
+                "2 files failed to reformat.",
+            )
+            self.assertEqual(report.return_code, 123)
+            report.done(Path("f4"), black.Changed.NO)
+            self.assertEqual(len(out_lines), 6)
+            self.assertEqual(len(err_lines), 2)
             self.assertEqual(out_lines[-1], "f4 already well formatted, good job.")
             self.assertEqual(
                 unstyle(str(report)),
@@ -463,6 +473,183 @@ def err(msg: str, **kwargs: Any) -> None:
                 "2 files would fail to reformat.",
             )
 
+    def test_report_quiet(self) -> None:
+        report = black.Report(quiet=True)
+        out_lines = []
+        err_lines = []
+
+        def out(msg: str, **kwargs: Any) -> None:
+            out_lines.append(msg)
+
+        def err(msg: str, **kwargs: Any) -> None:
+            err_lines.append(msg)
+
+        with patch("black.out", out), patch("black.err", err):
+            report.done(Path("f1"), black.Changed.NO)
+            self.assertEqual(len(out_lines), 0)
+            self.assertEqual(len(err_lines), 0)
+            self.assertEqual(unstyle(str(report)), "1 file left unchanged.")
+            self.assertEqual(report.return_code, 0)
+            report.done(Path("f2"), black.Changed.YES)
+            self.assertEqual(len(out_lines), 0)
+            self.assertEqual(len(err_lines), 0)
+            self.assertEqual(
+                unstyle(str(report)), "1 file reformatted, 1 file left unchanged."
+            )
+            report.done(Path("f3"), black.Changed.CACHED)
+            self.assertEqual(len(out_lines), 0)
+            self.assertEqual(len(err_lines), 0)
+            self.assertEqual(
+                unstyle(str(report)), "1 file reformatted, 2 files left unchanged."
+            )
+            self.assertEqual(report.return_code, 0)
+            report.check = True
+            self.assertEqual(report.return_code, 1)
+            report.check = False
+            report.failed(Path("e1"), "boom")
+            self.assertEqual(len(out_lines), 0)
+            self.assertEqual(len(err_lines), 1)
+            self.assertEqual(err_lines[-1], "error: cannot format e1: boom")
+            self.assertEqual(
+                unstyle(str(report)),
+                "1 file reformatted, 2 files left unchanged, "
+                "1 file failed to reformat.",
+            )
+            self.assertEqual(report.return_code, 123)
+            report.done(Path("f3"), black.Changed.YES)
+            self.assertEqual(len(out_lines), 0)
+            self.assertEqual(len(err_lines), 1)
+            self.assertEqual(
+                unstyle(str(report)),
+                "2 files reformatted, 2 files left unchanged, "
+                "1 file failed to reformat.",
+            )
+            self.assertEqual(report.return_code, 123)
+            report.failed(Path("e2"), "boom")
+            self.assertEqual(len(out_lines), 0)
+            self.assertEqual(len(err_lines), 2)
+            self.assertEqual(err_lines[-1], "error: cannot format e2: boom")
+            self.assertEqual(
+                unstyle(str(report)),
+                "2 files reformatted, 2 files left unchanged, "
+                "2 files failed to reformat.",
+            )
+            self.assertEqual(report.return_code, 123)
+            report.path_ignored(Path("wat"), "no match")
+            self.assertEqual(len(out_lines), 0)
+            self.assertEqual(len(err_lines), 2)
+            self.assertEqual(
+                unstyle(str(report)),
+                "2 files reformatted, 2 files left unchanged, "
+                "2 files failed to reformat.",
+            )
+            self.assertEqual(report.return_code, 123)
+            report.done(Path("f4"), black.Changed.NO)
+            self.assertEqual(len(out_lines), 0)
+            self.assertEqual(len(err_lines), 2)
+            self.assertEqual(
+                unstyle(str(report)),
+                "2 files reformatted, 3 files left unchanged, "
+                "2 files failed to reformat.",
+            )
+            self.assertEqual(report.return_code, 123)
+            report.check = True
+            self.assertEqual(
+                unstyle(str(report)),
+                "2 files would be reformatted, 3 files would be left unchanged, "
+                "2 files would fail to reformat.",
+            )
+
+    def test_report_normal(self) -> None:
+        report = black.Report()
+        out_lines = []
+        err_lines = []
+
+        def out(msg: str, **kwargs: Any) -> None:
+            out_lines.append(msg)
+
+        def err(msg: str, **kwargs: Any) -> None:
+            err_lines.append(msg)
+
+        with patch("black.out", out), patch("black.err", err):
+            report.done(Path("f1"), black.Changed.NO)
+            self.assertEqual(len(out_lines), 0)
+            self.assertEqual(len(err_lines), 0)
+            self.assertEqual(unstyle(str(report)), "1 file left unchanged.")
+            self.assertEqual(report.return_code, 0)
+            report.done(Path("f2"), black.Changed.YES)
+            self.assertEqual(len(out_lines), 1)
+            self.assertEqual(len(err_lines), 0)
+            self.assertEqual(out_lines[-1], "reformatted f2")
+            self.assertEqual(
+                unstyle(str(report)), "1 file reformatted, 1 file left unchanged."
+            )
+            report.done(Path("f3"), black.Changed.CACHED)
+            self.assertEqual(len(out_lines), 1)
+            self.assertEqual(len(err_lines), 0)
+            self.assertEqual(out_lines[-1], "reformatted f2")
+            self.assertEqual(
+                unstyle(str(report)), "1 file reformatted, 2 files left unchanged."
+            )
+            self.assertEqual(report.return_code, 0)
+            report.check = True
+            self.assertEqual(report.return_code, 1)
+            report.check = False
+            report.failed(Path("e1"), "boom")
+            self.assertEqual(len(out_lines), 1)
+            self.assertEqual(len(err_lines), 1)
+            self.assertEqual(err_lines[-1], "error: cannot format e1: boom")
+            self.assertEqual(
+                unstyle(str(report)),
+                "1 file reformatted, 2 files left unchanged, "
+                "1 file failed to reformat.",
+            )
+            self.assertEqual(report.return_code, 123)
+            report.done(Path("f3"), black.Changed.YES)
+            self.assertEqual(len(out_lines), 2)
+            self.assertEqual(len(err_lines), 1)
+            self.assertEqual(out_lines[-1], "reformatted f3")
+            self.assertEqual(
+                unstyle(str(report)),
+                "2 files reformatted, 2 files left unchanged, "
+                "1 file failed to reformat.",
+            )
+            self.assertEqual(report.return_code, 123)
+            report.failed(Path("e2"), "boom")
+            self.assertEqual(len(out_lines), 2)
+            self.assertEqual(len(err_lines), 2)
+            self.assertEqual(err_lines[-1], "error: cannot format e2: boom")
+            self.assertEqual(
+                unstyle(str(report)),
+                "2 files reformatted, 2 files left unchanged, "
+                "2 files failed to reformat.",
+            )
+            self.assertEqual(report.return_code, 123)
+            report.path_ignored(Path("wat"), "no match")
+            self.assertEqual(len(out_lines), 2)
+            self.assertEqual(len(err_lines), 2)
+            self.assertEqual(
+                unstyle(str(report)),
+                "2 files reformatted, 2 files left unchanged, "
+                "2 files failed to reformat.",
+            )
+            self.assertEqual(report.return_code, 123)
+            report.done(Path("f4"), black.Changed.NO)
+            self.assertEqual(len(out_lines), 2)
+            self.assertEqual(len(err_lines), 2)
+            self.assertEqual(
+                unstyle(str(report)),
+                "2 files reformatted, 3 files left unchanged, "
+                "2 files failed to reformat.",
+            )
+            self.assertEqual(report.return_code, 123)
+            report.check = True
+            self.assertEqual(
+                unstyle(str(report)),
+                "2 files would be reformatted, 3 files would be left unchanged, "
+                "2 files would fail to reformat.",
+            )
+
     def test_is_python36(self) -> None:
         node = black.lib2to3_parse("def f(*, arg): ...\n")
         self.assertFalse(black.is_python36(node))
@@ -859,17 +1046,21 @@ def test_include_exclude(self) -> None:
         path = THIS_DIR / "include_exclude_tests"
         include = re.compile(r"\.pyi?$")
         exclude = re.compile(r"/exclude/|/\.definitely_exclude/")
+        report = black.Report()
         sources: List[Path] = []
         expected = [
             Path(THIS_DIR / "include_exclude_tests/b/dont_exclude/a.py"),
             Path(THIS_DIR / "include_exclude_tests/b/dont_exclude/a.pyi"),
         ]
         this_abs = THIS_DIR.resolve()
-        sources.extend(black.gen_python_files_in_dir(path, this_abs, include, exclude))
+        sources.extend(
+            black.gen_python_files_in_dir(path, this_abs, include, exclude, report)
+        )
         self.assertEqual(sorted(expected), sorted(sources))
 
     def test_empty_include(self) -> None:
         path = THIS_DIR / "include_exclude_tests"
+        report = black.Report()
         empty = re.compile(r"")
         sources: List[Path] = []
         expected = [
@@ -886,13 +1077,14 @@ def test_empty_include(self) -> None:
         this_abs = THIS_DIR.resolve()
         sources.extend(
             black.gen_python_files_in_dir(
-                path, this_abs, empty, re.compile(black.DEFAULT_EXCLUDES)
+                path, this_abs, empty, re.compile(black.DEFAULT_EXCLUDES), report
             )
         )
         self.assertEqual(sorted(expected), sorted(sources))
 
     def test_empty_exclude(self) -> None:
         path = THIS_DIR / "include_exclude_tests"
+        report = black.Report()
         empty = re.compile(r"")
         sources: List[Path] = []
         expected = [
@@ -906,7 +1098,7 @@ def test_empty_exclude(self) -> None:
         this_abs = THIS_DIR.resolve()
         sources.extend(
             black.gen_python_files_in_dir(
-                path, this_abs, re.compile(black.DEFAULT_INCLUDES), empty
+                path, this_abs, re.compile(black.DEFAULT_INCLUDES), empty, report
             )
         )
         self.assertEqual(sorted(expected), sorted(sources))