Update and fix Flake8 (#1424)

* Update pre-commit

* Fix F541 f-string is missing placeholders

* Fix E741 ambiguous variable name 'l'

* Update actions to v2

.github/workflows/lint.yml

@@ -10,10 +10,10 @@ jobs:
         python-version: [3.7]
 
     steps:
-      - uses: actions/checkout@v1
+      - uses: actions/checkout@v2
 
       - name: Set up Python ${{ matrix.python-version }}
-        uses: actions/setup-python@v1
+        uses: actions/setup-python@v2
         with:
           python-version: ${{ matrix.python-version }}
 

.github/workflows/test.yml

@@ -12,10 +12,10 @@ jobs:
         os: [ubuntu-latest, macOS-latest, windows-latest]
 
     steps:
-      - uses: actions/checkout@v1
+      - uses: actions/checkout@v2
 
       - name: Set up Python ${{ matrix.python-version }}
-        uses: actions/setup-python@v1
+        uses: actions/setup-python@v2
         with:
           python-version: ${{ matrix.python-version }}
 

.pre-commit-config.yaml

@@ -12,13 +12,13 @@ repos:
         types: [python]
 
   - repo: https://gitlab.com/pycqa/flake8
-    rev: 3.7.9
+    rev: 3.8.1
     hooks:
       - id: flake8
         additional_dependencies: [flake8-bugbear]
 
   - repo: https://github.com/pre-commit/mirrors-mypy
-    rev: v0.761
+    rev: v0.770
     hooks:
       - id: mypy
         exclude: ^docs/conf.py

src/black/__init__.py

@@ -310,7 +310,7 @@ def read_pyproject_toml(
     target_version = config.get("target_version")
     if target_version is not None and not isinstance(target_version, list):
         raise click.BadOptionUsage(
-            "target-version", f"Config key target-version must be a list"
+            "target-version", "Config key target-version must be a list"
         )
 
     default_map: Dict[str, Any] = {}
@@ -1633,8 +1633,10 @@ def contains_unsplittable_type_ignore(self) -> bool:
         # one line in the original code.
 
         # Grab the first and last line numbers, skipping generated leaves
-        first_line = next((l.lineno for l in self.leaves if l.lineno != 0), 0)
-        last_line = next((l.lineno for l in reversed(self.leaves) if l.lineno != 0), 0)
+        first_line = next((leaf.lineno for leaf in self.leaves if leaf.lineno != 0), 0)
+        last_line = next(
+            (leaf.lineno for leaf in reversed(self.leaves) if leaf.lineno != 0), 0
+        )
 
         if first_line == last_line:
             # We look at the last two leaves since a comma or an
@@ -2710,15 +2712,15 @@ def rhs(line: Line, features: Collection[Feature]) -> Iterator[Line]:
         # split altogether.
         result: List[Line] = []
         try:
-            for l in transform(line, features):
-                if str(l).strip("\n") == line_str:
+            for transformed_line in transform(line, features):
+                if str(transformed_line).strip("\n") == line_str:
                     raise CannotTransform(
                         "Line transformer returned an unchanged result"
                     )
 
                 result.extend(
                     transform_line(
-                        l,
+                        transformed_line,
                         line_length=line_length,
                         normalize_strings=normalize_strings,
                         features=features,
@@ -4836,7 +4838,7 @@ def bracket_split_build_line(
             no_commas = (
                 original.is_def
                 and opening_bracket.value == "("
-                and not any(l.type == token.COMMA for l in leaves)
+                and not any(leaf.type == token.COMMA for leaf in leaves)
             )
 
             if original.is_import or no_commas:
@@ -4866,9 +4868,9 @@ def dont_increase_indentation(split_func: Transformer) -> Transformer:
 
     @wraps(split_func)
     def split_wrapper(line: Line, features: Collection[Feature] = ()) -> Iterator[Line]:
-        for l in split_func(line, features):
-            normalize_prefix(l.leaves[0], inside_brackets=True)
-            yield l
+        for line in split_func(line, features):
+            normalize_prefix(line.leaves[0], inside_brackets=True)
+            yield line
 
     return split_wrapper
 

src/black_primer/cli.py

@@ -50,7 +50,7 @@ async def async_main(
         work_path.mkdir()
 
     if not which("black"):
-        LOG.error(f"Can not find 'black' executable in PATH. No point in running")
+        LOG.error("Can not find 'black' executable in PATH. No point in running")
         return -1
 
     try:

src/black_primer/lib.py

@@ -57,7 +57,7 @@ async def analyze_results(project_count: int, results: Results) -> int:
     failed_pct = round(((results.stats["failed"] / project_count) * 100), 2)
     success_pct = round(((results.stats["success"] / project_count) * 100), 2)
 
-    click.secho(f"-- primer results 📊 --\n", bold=True)
+    click.secho("-- primer results 📊 --\n", bold=True)
     click.secho(
         f"{results.stats['success']} / {project_count} succeeded ({success_pct}%) ✅",
         bold=True,
@@ -77,7 +77,7 @@ async def analyze_results(project_count: int, results: Results) -> int:
     )
 
     if results.failed_projects:
-        click.secho(f"\nFailed Projects:\n", bold=True)
+        click.secho("\nFailed Projects:\n", bold=True)
 
     for project_name, project_cpe in results.failed_projects.items():
         print(f"## {project_name}:")
@@ -125,7 +125,7 @@ async def git_checkout_or_rebase(
     """git Clone project or rebase"""
     git_bin = str(which("git"))
     if not git_bin:
-        LOG.error(f"No git binary found")
+        LOG.error("No git binary found")
         return None
 
     repo_url_parts = urlparse(project_config["git_clone_url"])

tests/test_black.py

@@ -252,8 +252,8 @@ def test_piping(self) -> None:
 
     def test_piping_diff(self) -> None:
         diff_header = re.compile(
-            rf"(STDIN|STDOUT)\t\d\d\d\d-\d\d-\d\d \d\d:\d\d:\d\d\.\d\d\d\d\d\d "
-            rf"\+\d\d\d\d"
+            r"(STDIN|STDOUT)\t\d\d\d\d-\d\d-\d\d \d\d:\d\d:\d\d\.\d\d\d\d\d\d "
+            r"\+\d\d\d\d"
         )
         source, _ = read_data("expression.py")
         expected, _ = read_data("expression.diff")
@@ -1848,7 +1848,7 @@ async def test_blackd_pyi(self) -> None:
     @unittest_run_loop
     async def test_blackd_diff(self) -> None:
         diff_header = re.compile(
-            rf"(In|Out)\t\d\d\d\d-\d\d-\d\d \d\d:\d\d:\d\d\.\d\d\d\d\d\d \+\d\d\d\d"
+            r"(In|Out)\t\d\d\d\d-\d\d-\d\d \d\d:\d\d:\d\d\.\d\d\d\d\d\d \+\d\d\d\d"
         )
 
         source, _ = read_data("blackd_diff.py")