Convert legacy string formatting to f-strings (#4685)

* the changes

* Update driver.py

.github/workflows/diff_shades.yml

@@ -34,7 +34,8 @@ jobs:
         env:
           GITHUB_TOKEN: ${{ github.token }}
         run: >
-          python scripts/diff_shades_gha_helper.py config ${{ github.event_name }} ${{ matrix.mode }}
+          python scripts/diff_shades_gha_helper.py config ${{ github.event_name }}
+          ${{ matrix.mode }}
 
   analysis:
     name: analysis / ${{ matrix.mode }}
@@ -48,7 +49,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        include: ${{ fromJson(needs.configure.outputs.matrix )}}
+        include: ${{ fromJson(needs.configure.outputs.matrix) }}
 
     steps:
       - name: Checkout this repository (full clone)
@@ -130,10 +131,9 @@ jobs:
       - name: Generate summary file (PR only)
         if: github.event_name == 'pull_request' && matrix.mode == 'preview-changes'
         run: >
-          python helper.py comment-body
-          ${{ matrix.baseline-analysis }} ${{ matrix.target-analysis }}
-          ${{ matrix.baseline-sha }} ${{ matrix.target-sha }}
-          ${{ github.event.pull_request.number }}
+          python helper.py comment-body ${{ matrix.baseline-analysis }}
+          ${{ matrix.target-analysis }} ${{ matrix.baseline-sha }}
+          ${{ matrix.target-sha }} ${{ github.event.pull_request.number }}
 
       - name: Upload summary file (PR only)
         if: github.event_name == 'pull_request' && matrix.mode == 'preview-changes'

.github/workflows/pypi_upload.yml

@@ -92,7 +92,7 @@ jobs:
     steps:
       - uses: actions/checkout@v4
       # Keep cibuildwheel version in sync with above
-      - uses: pypa/cibuildwheel@v2.22.0
+      - uses: pypa/cibuildwheel@v2.23.3
         with:
           only: ${{ matrix.only }}
 

.pre-commit-config.yaml

@@ -24,12 +24,12 @@ repos:
         additional_dependencies: *version_check_dependencies
 
   - repo: https://github.com/pycqa/isort
-    rev: 5.13.2
+    rev: 6.0.1
     hooks:
       - id: isort
 
   - repo: https://github.com/pycqa/flake8
-    rev: 7.1.1
+    rev: 7.2.0
     hooks:
       - id: flake8
         additional_dependencies:
@@ -48,7 +48,9 @@ repos:
           - types-PyYAML
           - types-atheris
           - tomli >= 0.2.6, < 2.0.0
-          - click >= 8.1.0, != 8.1.4, != 8.1.5
+          - click >= 8.2.0
+          # Click is intentionally out-of-sync with pyproject.toml
+          # v8.2 has breaking changes. We work around them at runtime, but we need the newer stubs.
           - packaging >= 22.0
           - platformdirs >= 2.1.0
           - pytokens >= 0.1.10
@@ -64,11 +66,11 @@ repos:
         args: ["--python-version=3.10"]
         additional_dependencies: *mypy_deps
 
-  - repo: https://github.com/pre-commit/mirrors-prettier
-    rev: v4.0.0-alpha.8
+  - repo: https://github.com/rbubley/mirrors-prettier
+    rev: v3.5.3
     hooks:
       - id: prettier
-        types_or: [css, javascript, html, json, yaml]
+        types_or: [markdown, yaml, json]
         exclude: \.github/workflows/diff_shades\.yml
 
   - repo: https://github.com/pre-commit/pre-commit-hooks

CHANGES.md

@@ -9,19 +9,24 @@
 ### Stable style
 
 <!-- Changes that affect Black's stable style -->
+
 - Fix crash while formatting a long `del` statement containing tuples (#4628)
-- Fix crash while formatting expressions using the walrus operator in complex
-  `with` statements (#4630)
+- Fix crash while formatting expressions using the walrus operator in complex `with`
+  statements (#4630)
 - Handle `# fmt: skip` followed by a comment at the end of file (#4635)
-- Fix crash when a tuple appears in the `as` clause of a `with` statement
-  (#4634)
+- Fix crash when a tuple appears in the `as` clause of a `with` statement (#4634)
+- Fix crash when tuple is used as a context manager inside a `with` statement (#4646)
+- Fix crash on a `\\r\n` (#4673)
+- Fix crash on `await ...` (where `...` is a literal `Ellipsis`) (#4676)
+- Remove support for pre-python 3.7 `await/async` as soft keywords/variable names
+  (#4676)
 
 ### Preview style
 
 <!-- Changes that affect Black's preview style -->
 
-- Fix a bug where one-liner functions/conditionals marked with `# fmt: skip`
-  would still be formatted (#4552)
+- Fix a bug where one-liner functions/conditionals marked with `# fmt: skip` would still
+  be formatted (#4552)
 
 ### Configuration
 
@@ -36,8 +41,8 @@
 <!-- Changes to the parser or to version autodetection -->
 
 - Rewrite tokenizer to improve performance and compliance (#4536)
-- Fix bug where certain unusual expressions (e.g., lambdas) were not accepted
-  in type parameter bounds and defaults. (#4602)
+- Fix bug where certain unusual expressions (e.g., lambdas) were not accepted in type
+  parameter bounds and defaults. (#4602)
 
 ### Performance
 
@@ -56,8 +61,8 @@
 <!-- For example, Docker, GitHub Actions, pre-commit, editors -->
 
 - Fix the version check in the vim file to reject Python 3.8 (#4567)
-- Enhance GitHub Action `psf/black` to read Black version from an additional
-  section in pyproject.toml: `[project.dependency-groups]` (#4606)
+- Enhance GitHub Action `psf/black` to read Black version from an additional section in
+  pyproject.toml: `[project.dependency-groups]` (#4606)
 
 ### Documentation
 
@@ -68,8 +73,8 @@
 
 ### Highlights
 
-This release introduces the new 2025 stable style (#4558), stabilizing
-the following changes:
+This release introduces the new 2025 stable style (#4558), stabilizing the following
+changes:
 
 - Normalize casing of Unicode escape characters in strings to lowercase (#2916)
 - Fix inconsistencies in whether certain strings are detected as docstrings (#4095)
@@ -77,15 +82,16 @@ the following changes:
 - Remove redundant parentheses in if guards for case blocks (#4214)
 - Add parentheses to if clauses in case blocks when the line is too long (#4269)
 - Whitespace before `# fmt: skip` comments is no longer normalized (#4146)
-- Fix line length computation for certain expressions that involve the power operator (#4154)
+- Fix line length computation for certain expressions that involve the power operator
+  (#4154)
 - Check if there is a newline before the terminating quotes of a docstring (#4185)
 - Fix type annotation spacing between `*` and more complex type variable tuple (#4440)
 
 The following changes were not in any previous release:
 
 - Remove parentheses around sole list items (#4312)
-- Generic function definitions are now formatted more elegantly: parameters are
-  split over multiple lines first instead of type parameter definitions (#4553)
+- Generic function definitions are now formatted more elegantly: parameters are split
+  over multiple lines first instead of type parameter definitions (#4553)
 
 ### Stable style
 

README.md

@@ -137,8 +137,8 @@ SQLAlchemy, Poetry, PyPA applications (Warehouse, Bandersnatch, Pipenv, virtuale
 pandas, Pillow, Twisted, LocalStack, every Datadog Agent Integration, Home Assistant,
 Zulip, Kedro, OpenOA, FLORIS, ORBIT, WOMBAT, and many more.
 
-The following organizations use _Black_: Dropbox, KeepTruckin, Lyft, Mozilla,
-Quora, Duolingo, QuantumBlack, Tesla, Archer Aviation.
+The following organizations use _Black_: Dropbox, KeepTruckin, Lyft, Mozilla, Quora,
+Duolingo, QuantumBlack, Tesla, Archer Aviation.
 
 Are we missing anyone? Let us know.
 

docs/contributing/release_process.md

@@ -29,8 +29,8 @@ frequently than monthly nets rapidly diminishing returns.
 **You must have `write` permissions for the _Black_ repository to cut a release.**
 
 The 10,000 foot view of the release process is that you prepare a release PR and then
-publish a [GitHub Release]. This triggers [release automation](#release-workflows) that builds
-all release artifacts and publishes them to the various platforms we publish to.
+publish a [GitHub Release]. This triggers [release automation](#release-workflows) that
+builds all release artifacts and publishes them to the various platforms we publish to.
 
 We now have a `scripts/release.py` script to help with cutting the release PRs.
 
@@ -96,8 +96,9 @@ In the end, use your best judgement and ask other maintainers for their thoughts
 
 ## Release workflows
 
-All of _Black_'s release automation uses [GitHub Actions]. All workflows are therefore configured
-using YAML files in the `.github/workflows` directory of the _Black_ repository.
+All of _Black_'s release automation uses [GitHub Actions]. All workflows are therefore
+configured using YAML files in the `.github/workflows` directory of the _Black_
+repository.
 
 They are triggered by the publication of a [GitHub Release].
 

docs/faq.md

@@ -93,6 +93,8 @@ Support for formatting Python 2 code was removed in version 22.0. While we've ma
 plans to stop supporting older Python 3 minor versions immediately, their support might
 also be removed some time in the future without a deprecation period.
 
+`await`/`async` as soft keywords/indentifiers are no longer supported as of 25.2.0.
+
 Runtime support for 3.6 was removed in version 22.10.0, for 3.7 in version 23.7.0, and
 for 3.8 in version 24.10.0.
 

docs/integrations/github_actions.md

@@ -38,9 +38,9 @@ the `pyproject.toml` file. `version` can be any
 or just the version number if you want an exact version. To read the version from the
 `pyproject.toml` file instead, set `use_pyproject` to `true`. This will first look into
 the `tool.black.required-version` field, then the `dependency-groups` table, then the
-`project.dependencies` array and finally the `project.optional-dependencies` table.
-The action defaults to the latest release available on PyPI. Only versions available
-from PyPI are supported, so no commit SHAs or branch names.
+`project.dependencies` array and finally the `project.optional-dependencies` table. The
+action defaults to the latest release available on PyPI. Only versions available from
+PyPI are supported, so no commit SHAs or branch names.
 
 If you want to include Jupyter Notebooks, _Black_ must be installed with the `jupyter`
 extra. Installing the extra and including Jupyter Notebook files can be configured via

scripts/fuzz.py

@@ -5,14 +5,11 @@
 a coverage-guided fuzzer I'm working on.
 """
 
-import re
-
 import hypothesmith
 from hypothesis import HealthCheck, given, settings
 from hypothesis import strategies as st
 
 import black
-from blib2to3.pgen2.tokenize import TokenError
 
 
 # This test uses the Hypothesis and Hypothesmith libraries to generate random
@@ -45,23 +42,7 @@ def test_idempotent_any_syntatically_valid_python(
     compile(src_contents, "<string>", "exec")  # else the bug is in hypothesmith
 
     # Then format the code...
-    try:
-        dst_contents = black.format_str(src_contents, mode=mode)
-    except black.InvalidInput:
-        # This is a bug - if it's valid Python code, as above, Black should be
-        # able to cope with it.  See issues #970, #1012
-        # TODO: remove this try-except block when issues are resolved.
-        return
-    except TokenError as e:
-        if (  # Special-case logic for backslashes followed by newlines or end-of-input
-            e.args[0] == "EOF in multi-line statement"
-            and re.search(r"\\($|\r?\n)", src_contents) is not None
-        ):
-            # This is a bug - if it's valid Python code, as above, Black should be
-            # able to cope with it.  See issue #1012.
-            # TODO: remove this block when the issue is resolved.
-            return
-        raise
+    dst_contents = black.format_str(src_contents, mode=mode)
 
     # And check that we got equivalent and stable output.
     black.assert_equivalent(src_contents, dst_contents)

scripts/migrate-black.py

@@ -77,7 +77,7 @@ def blackify(base_branch: str, black_command: str, logger: logging.Logger) -> in
         git("commit", "--allow-empty", "-aqC", commit)
 
     for commit in commits:
-        git("branch", "-qD", "%s-black" % commit)
+        git("branch", "-qD", f"{commit}-black")
 
     return 0
 

src/black/linegen.py

@@ -40,6 +40,7 @@
     ensure_visible,
     fstring_to_string,
     get_annotation_type,
+    has_sibling_with_type,
     is_arith_like,
     is_async_stmt_or_funcdef,
     is_atom_with_invisible_parens,
@@ -1628,6 +1629,11 @@ def maybe_make_parens_invisible_in_atom(
         or is_empty_tuple(node)
         or is_one_tuple(node)
         or (is_tuple(node) and parent.type == syms.asexpr_test)
+        or (
+            is_tuple(node)
+            and parent.type == syms.with_stmt
+            and has_sibling_with_type(node, token.COMMA)
+        )
         or (is_yield(node) and parent.type != syms.expr_stmt)
         or (
             # This condition tries to prevent removing non-optional brackets

src/black/nodes.py

@@ -1058,3 +1058,21 @@ def furthest_ancestor_with_last_leaf(leaf: Leaf) -> LN:
     while node.parent and node.parent.children and node is node.parent.children[-1]:
         node = node.parent
     return node
+
+
+def has_sibling_with_type(node: LN, type: int) -> bool:
+    # Check previous siblings
+    sibling = node.prev_sibling
+    while sibling is not None:
+        if sibling.type == type:
+            return True
+        sibling = sibling.prev_sibling
+
+    # Check next siblings
+    sibling = node.next_sibling
+    while sibling is not None:
+        if sibling.type == type:
+            return True
+        sibling = sibling.next_sibling
+
+    return False

src/blib2to3/pgen2/literals.py

@@ -28,16 +28,16 @@ def escape(m: re.Match[str]) -> str:
     if tail.startswith("x"):
         hexes = tail[1:]
         if len(hexes) < 2:
-            raise ValueError("invalid hex string escape ('\\%s')" % tail)
+            raise ValueError(f"invalid hex string escape ('\\{tail}')")
         try:
             i = int(hexes, 16)
         except ValueError:
-            raise ValueError("invalid hex string escape ('\\%s')" % tail) from None
+            raise ValueError(f"invalid hex string escape ('\\{tail}')") from None
     else:
         try:
             i = int(tail, 8)
         except ValueError:
-            raise ValueError("invalid octal string escape ('\\%s')" % tail) from None
+            raise ValueError(f"invalid octal string escape ('\\{tail}')") from None
     return chr(i)
 
 

src/blib2to3/pgen2/parse.py

@@ -89,18 +89,12 @@ def backtrack(self) -> Iterator[None]:
             self.parser.is_backtracking = is_backtracking
 
     def add_token(self, tok_type: int, tok_val: str, raw: bool = False) -> None:
-        func: Callable[..., Any]
-        if raw:
-            func = self.parser._addtoken
-        else:
-            func = self.parser.addtoken
-
         for ilabel in self.ilabels:
             with self.switch_to(ilabel):
-                args = [tok_type, tok_val, self.context]
                 if raw:
-                    args.insert(0, ilabel)
-                func(*args)
+                    self.parser._addtoken(ilabel, tok_type, tok_val, self.context)
+                else:
+                    self.parser.addtoken(tok_type, tok_val, self.context)
 
     def determine_route(
         self, value: Optional[str] = None, force: bool = False

src/blib2to3/pgen2/pgen.py

@@ -140,7 +140,7 @@ def calcfirst(self, name: str) -> None:
                 if label in self.first:
                     fset = self.first[label]
                     if fset is None:
-                        raise ValueError("recursion for rule %r" % name)
+                        raise ValueError(f"recursion for rule {name!r}")
                 else:
                     self.calcfirst(label)
                     fset = self.first[label]
@@ -155,8 +155,8 @@ def calcfirst(self, name: str) -> None:
             for symbol in itsfirst:
                 if symbol in inverse:
                     raise ValueError(
-                        "rule %s is ambiguous; %s is in the first sets of %s as well"
-                        " as %s" % (name, symbol, label, inverse[symbol])
+                        f"rule {name} is ambiguous; {symbol} is in the first sets of"
+                        f" {label} as well as {inverse[symbol]}"
                     )
                 inverse[symbol] = label
         self.first[name] = totalset
@@ -237,16 +237,16 @@ def dump_nfa(self, name: str, start: "NFAState", finish: "NFAState") -> None:
                     j = len(todo)
                     todo.append(next)
                 if label is None:
-                    print("    -> %d" % j)
+                    print(f"    -> {j}")
                 else:
-                    print("    %s -> %d" % (label, j))
+                    print(f"    {label} -> {j}")
 
     def dump_dfa(self, name: str, dfa: Sequence["DFAState"]) -> None:
         print("Dump of DFA for", name)
         for i, state in enumerate(dfa):
             print("  State", i, state.isfinal and "(final)" or "")
             for label, next in sorted(state.arcs.items()):
-                print("    %s -> %d" % (label, dfa.index(next)))
+                print(f"    {label} -> {dfa.index(next)}")
 
     def simplify_dfa(self, dfa: list["DFAState"]) -> None:
         # This is not theoretically optimal, but works well enough.
@@ -330,15 +330,12 @@ def parse_atom(self) -> tuple["NFAState", "NFAState"]:
             return a, z
         else:
             self.raise_error(
-                "expected (...) or NAME or STRING, got %s/%s", self.type, self.value
+                f"expected (...) or NAME or STRING, got {self.type}/{self.value}"
             )
-            raise AssertionError
 
     def expect(self, type: int, value: Optional[Any] = None) -> str:
         if self.type != type or (value is not None and self.value != value):
-            self.raise_error(
-                "expected %s/%s, got %s/%s", type, value, self.type, self.value
-            )
+            self.raise_error(f"expected {type}/{value}, got {self.type}/{self.value}")
         value = self.value
         self.gettoken()
         return value
@@ -350,12 +347,7 @@ def gettoken(self) -> None:
         self.type, self.value, self.begin, self.end, self.line = tup
         # print token.tok_name[self.type], repr(self.value)
 
-    def raise_error(self, msg: str, *args: Any) -> NoReturn:
-        if args:
-            try:
-                msg = msg % args
-            except Exception:
-                msg = " ".join([msg] + list(map(str, args)))
+    def raise_error(self, msg: str) -> NoReturn:
         raise SyntaxError(
             msg, (str(self.filename), self.end[0], self.end[1], self.line)
         )

src/blib2to3/pgen2/tokenize.py

@@ -113,7 +113,17 @@ def transform_whitespace(
         and prev_token.type not in (TokenType.nl, TokenType.newline)
     ):
         token_str = source[token.start_index : token.end_index]
-        if token_str.startswith("\\\n"):
+        if token_str.startswith("\\\r\n"):
+            return pytokens.Token(
+                TokenType.nl,
+                token.start_index,
+                token.start_index + 3,
+                token.start_line,
+                token.start_col,
+                token.start_line,
+                token.start_col + 3,
+            )
+        elif token_str.startswith("\\\n") or token_str.startswith("\\\r"):
             return pytokens.Token(
                 TokenType.nl,
                 token.start_index,
@@ -128,20 +138,13 @@ def transform_whitespace(
 
 
 def tokenize(source: str, grammar: Optional[Grammar] = None) -> Iterator[TokenInfo]:
-    async_keywords = False if grammar is None else grammar.async_keywords
-
     lines = source.split("\n")
     lines += [""]  # For newline tokens in files that don't end in a newline
     line, column = 1, 0
 
-    token_iterator = pytokens.tokenize(source)
-    is_async = False
-    current_indent = 0
-    async_indent = 0
-
     prev_token: Optional[pytokens.Token] = None
     try:
-        for token in token_iterator:
+        for token in pytokens.tokenize(source):
             token = transform_whitespace(token, source, prev_token)
 
             line, column = token.start_line, token.start_col
@@ -156,58 +159,18 @@ def tokenize(source: str, grammar: Optional[Grammar] = None) -> Iterator[TokenIn
                 prev_token = token
                 continue
 
-            if token.type == TokenType.indent:
-                current_indent += 1
-            if token.type == TokenType.dedent:
-                current_indent -= 1
-                if is_async and current_indent < async_indent:
-                    is_async = False
-
             source_line = lines[token.start_line - 1]
 
             if token.type == TokenType.identifier and token_str in ("async", "await"):
                 # Black uses `async` and `await` token types just for those two keywords
-                while True:
-                    next_token = next(token_iterator)
-                    next_str = source[next_token.start_index : next_token.end_index]
-                    next_token = transform_whitespace(next_token, next_str, token)
-                    if next_token.type == TokenType.whitespace:
-                        continue
-                    break
-
-                next_token_type = TOKEN_TYPE_MAP[next_token.type]
-                next_line = lines[next_token.start_line - 1]
-
-                if token_str == "async" and (
-                    async_keywords
-                    or (next_token_type == NAME and next_str in ("def", "for"))
-                ):
-                    is_async = True
-                    async_indent = current_indent + 1
-                    current_token_type = ASYNC
-                elif token_str == "await" and (async_keywords or is_async):
-                    current_token_type = AWAIT
-                else:
-                    current_token_type = TOKEN_TYPE_MAP[token.type]
-
                 yield (
-                    current_token_type,
+                    ASYNC if token_str == "async" else AWAIT,
                     token_str,
                     (token.start_line, token.start_col),
                     (token.end_line, token.end_col),
                     source_line,
                 )
-                yield (
-                    next_token_type,
-                    next_str,
-                    (next_token.start_line, next_token.start_col),
-                    (next_token.end_line, next_token.end_col),
-                    next_line,
-                )
-                prev_token = token
-                continue
-
-            if token.type == TokenType.op and token_str == "...":
+            elif token.type == TokenType.op and token_str == "...":
                 # Black doesn't have an ellipsis token yet, yield 3 DOTs instead
                 assert token.start_line == token.end_line
                 assert token.end_col == token.start_col + 3
@@ -222,16 +185,14 @@ def tokenize(source: str, grammar: Optional[Grammar] = None) -> Iterator[TokenIn
                         (token.end_line, end_col),
                         source_line,
                     )
-                prev_token = token
-                continue
-
-            yield (
-                TOKEN_TYPE_MAP[token.type],
-                token_str,
-                (token.start_line, token.start_col),
-                (token.end_line, token.end_col),
-                source_line,
-            )
+            else:
+                yield (
+                    TOKEN_TYPE_MAP[token.type],
+                    token_str,
+                    (token.start_line, token.start_col),
+                    (token.end_line, token.end_col),
+                    source_line,
+                )
             prev_token = token
 
     except pytokens.UnexpectedEOF:
@@ -245,9 +206,7 @@ def printtoken(
 ) -> None:  # for testing
     (srow, scol) = srow_col
     (erow, ecol) = erow_col
-    print(
-        "%d,%d-%d,%d:\t%s\t%s" % (srow, scol, erow, ecol, tok_name[type], repr(token))
-    )
+    print(f"{srow},{scol}-{erow},{ecol}:\t{tok_name[type]}\t{token!r}")
 
 
 if __name__ == "__main__":  # testing

src/blib2to3/pytree.py

@@ -268,11 +268,7 @@ def __init__(
     def __repr__(self) -> str:
         """Return a canonical string representation."""
         assert self.type is not None
-        return "{}({}, {!r})".format(
-            self.__class__.__name__,
-            type_repr(self.type),
-            self.children,
-        )
+        return f"{self.__class__.__name__}({type_repr(self.type)}, {self.children!r})"
 
     def __str__(self) -> str:
         """
@@ -421,10 +417,9 @@ def __repr__(self) -> str:
         from .pgen2.token import tok_name
 
         assert self.type is not None
-        return "{}({}, {!r})".format(
-            self.__class__.__name__,
-            tok_name.get(self.type, self.type),
-            self.value,
+        return (
+            f"{self.__class__.__name__}({tok_name.get(self.type, self.type)},"
+            f" {self.value!r})"
         )
 
     def __str__(self) -> str:
@@ -527,7 +522,7 @@ def __repr__(self) -> str:
         args = [type_repr(self.type), self.content, self.name]
         while args and args[-1] is None:
             del args[-1]
-        return "{}({})".format(self.__class__.__name__, ", ".join(map(repr, args)))
+        return f"{self.__class__.__name__}({', '.join(map(repr, args))})"
 
     def _submatch(self, node, results=None) -> bool:
         raise NotImplementedError

tests/data/cases/context_managers_39.py

@@ -89,6 +89,26 @@ async def func():
 with (x, y) as z:
     pass
 
+
+# don't remove the brackets here, it changes the meaning of the code.
+# even though the code will always trigger a runtime error
+with (name_5, name_4), name_5:
+    pass
+
+
+def test_tuple_as_contextmanager():
+    from contextlib import nullcontext
+
+    try:
+        with (nullcontext(),nullcontext()),nullcontext():
+            pass
+    except TypeError: 
+        # test passed
+        pass
+    else:
+        # this should be a type error
+        assert False
+
 # output
 
 
@@ -182,3 +202,23 @@ async def func():
 # don't remove the brackets here, it changes the meaning of the code.
 with (x, y) as z:
     pass
+
+
+# don't remove the brackets here, it changes the meaning of the code.
+# even though the code will always trigger a runtime error
+with (name_5, name_4), name_5:
+    pass
+
+
+def test_tuple_as_contextmanager():
+    from contextlib import nullcontext
+
+    try:
+        with (nullcontext(), nullcontext()), nullcontext():
+            pass
+    except TypeError:
+        # test passed
+        pass
+    else:
+        # this should be a type error
+        assert False

tests/data/cases/python37.py

@@ -10,6 +10,7 @@ def g():
 
 
 async def func():
+    await ...
     if test:
         out_batched = [
             i
@@ -42,6 +43,7 @@ def g():
 
 
 async def func():
+    await ...
     if test:
         out_batched = [
             i

tests/test_black.py

@@ -119,7 +119,7 @@ def __init__(self) -> None:
         if Version(imp_version("click")) >= Version("8.2.0"):
             super().__init__()
         else:
-            super().__init__(mix_stderr=False)
+            super().__init__(mix_stderr=False)  # type: ignore
 
 
 def invokeBlack(
@@ -422,21 +422,6 @@ def test_skip_magic_trailing_comma(self) -> None:
             )
             self.assertEqual(expected, actual, msg)
 
-    @patch("black.dump_to_file", dump_to_stderr)
-    def test_async_as_identifier(self) -> None:
-        source_path = get_case_path("miscellaneous", "async_as_identifier")
-        _, source, expected = read_data_from_file(source_path)
-        actual = fs(source)
-        self.assertFormatEqual(expected, actual)
-        major, minor = sys.version_info[:2]
-        if major < 3 or (major <= 3 and minor < 7):
-            black.assert_equivalent(source, actual)
-        black.assert_stable(source, actual, DEFAULT_MODE)
-        # ensure black can parse this when the target is 3.6
-        self.invokeBlack([str(source_path), "--target-version", "py36"])
-        # but not on 3.7, because async/await is no longer an identifier
-        self.invokeBlack([str(source_path), "--target-version", "py37"], exit_code=123)
-
     @patch("black.dump_to_file", dump_to_stderr)
     def test_python37(self) -> None:
         source_path = get_case_path("cases", "python37")
@@ -449,8 +434,6 @@ def test_python37(self) -> None:
         black.assert_stable(source, actual, DEFAULT_MODE)
         # ensure black can parse this when the target is 3.7
         self.invokeBlack([str(source_path), "--target-version", "py37"])
-        # but not on 3.6, because we use async as a reserved keyword
-        self.invokeBlack([str(source_path), "--target-version", "py36"], exit_code=123)
 
     def test_tab_comment_indentation(self) -> None:
         contents_tab = "if 1:\n\tif 2:\n\t\tpass\n\t# comment\n\tpass\n"
@@ -1907,7 +1890,8 @@ def test_code_option_safe(self) -> None:
             args = ["--safe", "--code", code]
             result = CliRunner().invoke(black.main, args)
 
-            self.compare_results(result, error_msg, 123)
+            assert error_msg == result.output
+            assert result.exit_code == 123
 
     def test_code_option_fast(self) -> None:
         """Test that the code option ignores errors when the sanity checks fail."""
@@ -2064,6 +2048,26 @@ def test_lines_with_leading_tabs_expanded(self) -> None:
         assert lines_with_leading_tabs_expanded("\t\tx") == [f"{tab}{tab}x"]
         assert lines_with_leading_tabs_expanded("\tx\n  y") == [f"{tab}x", "  y"]
 
+    def test_backslash_carriage_return(self) -> None:
+        # These tests are here instead of in the normal cases because
+        # of git's newline normalization and because it's hard to
+        # get `\r` vs `\r\n` vs `\n` to display properly in editors
+        assert black.format_str("x=\\\r\n1", mode=black.FileMode()) == "x = 1\n"
+        assert black.format_str("x=\\\n1", mode=black.FileMode()) == "x = 1\n"
+        assert black.format_str("x=\\\r1", mode=black.FileMode()) == "x = 1\n"
+        assert (
+            black.format_str("class A\\\r\n:...", mode=black.FileMode())
+            == "class A: ...\n"
+        )
+        assert (
+            black.format_str("class A\\\n:...", mode=black.FileMode())
+            == "class A: ...\n"
+        )
+        assert (
+            black.format_str("class A\\\r:...", mode=black.FileMode())
+            == "class A: ...\n"
+        )
+
 
 class TestCaching:
     def test_get_cache_dir(

tox.ini

@@ -13,18 +13,16 @@ skip_install = True
 recreate = True
 deps =
     -r{toxinidir}/test_requirements.txt
-; parallelization is disabled on CI because pytest-dev/pytest-xdist#620 occurs too frequently
-; local runs can stay parallelized since they aren't rolling the dice so many times as like on CI
 commands =
     pip install -e .[d]
     coverage erase
     pytest tests --run-optional no_jupyter \
-        !ci: --numprocesses auto \
+        --numprocesses auto \
         --cov {posargs}
     pip install -e .[jupyter]
     pytest tests --run-optional jupyter \
         -m jupyter \
-        !ci: --numprocesses auto \
+        --numprocesses auto \
         --cov --cov-append {posargs}
     coverage report
 
@@ -34,20 +32,15 @@ skip_install = True
 recreate = True
 deps =
     -r{toxinidir}/test_requirements.txt
-; a separate worker is required in ci due to https://foss.heptapod.net/pypy/pypy/-/issues/3317
-; this seems to cause tox to wait forever
-; remove this when pypy releases the bugfix
 commands =
     pip install -e .[d]
     pytest tests \
         --run-optional no_jupyter \
-        !ci: --numprocesses auto \
-        ci: --numprocesses 1
+        --numprocesses auto
     pip install -e .[jupyter]
     pytest tests --run-optional jupyter \
         -m jupyter \
-        !ci: --numprocesses auto \
-        ci: --numprocesses 1
+        --numprocesses auto
 
 [testenv:{,ci-}311]
 setenv =
@@ -59,22 +52,17 @@ deps =
 ; We currently need > aiohttp 3.8.1 that is on PyPI for 3.11
     git+https://github.com/aio-libs/aiohttp
     -r{toxinidir}/test_requirements.txt
-; a separate worker is required in ci due to https://foss.heptapod.net/pypy/pypy/-/issues/3317
-; this seems to cause tox to wait forever
-; remove this when pypy releases the bugfix
 commands =
     pip install -e .[d]
     coverage erase
     pytest tests \
         --run-optional no_jupyter \
-        !ci: --numprocesses auto \
-        ci: --numprocesses 1 \
+        --numprocesses auto \
         --cov {posargs}
     pip install -e .[jupyter]
     pytest tests --run-optional jupyter \
         -m jupyter \
-        !ci: --numprocesses auto \
-        ci: --numprocesses 1 \
+        --numprocesses auto \
         --cov --cov-append {posargs}
     coverage report