Update black to 26.1.0 (#20615)

cdce8p · web-flow · commit 5d6346386248 · 2026-01-18T23:04:26.000Z
https://github.com/psf/black/releases/tag/26.1.0
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
@@ -6,7 +6,7 @@ repos:
       - id: trailing-whitespace
       - id: end-of-file-fixer
   - repo: https://github.com/psf/black-pre-commit-mirror
-    rev: 25.9.0
+    rev: 26.1.0
     hooks:
       - id: black
         exclude: '^(test-data/)'
diff --git a/misc/sync-typeshed.py b/misc/sync-typeshed.py
@@ -184,14 +184,12 @@ def main() -> None:
         assert commit
 
         # Create a commit
-        message = textwrap.dedent(
-            f"""\
+        message = textwrap.dedent(f"""\
             Sync typeshed
 
             Source commit:
             https://github.com/python/typeshed/commit/{commit}
-            """
-        )
+            """)
         subprocess.run(["git", "add", "--all", os.path.join("mypy", "typeshed")], check=True)
         subprocess.run(["git", "commit", "-m", message], check=True)
         print("Created typeshed sync commit.")
diff --git a/mypy/build.py b/mypy/build.py
@@ -1432,12 +1432,10 @@ def exclude_from_backups(target_dir: str) -> None:
     cachedir_tag = os.path.join(target_dir, "CACHEDIR.TAG")
     try:
         with open(cachedir_tag, "x") as f:
-            f.write(
-                """Signature: 8a477f597d28d172789f06886806bc55
+            f.write("""Signature: 8a477f597d28d172789f06886806bc55
 # This file is a cache directory tag automatically created by mypy.
 # For information about cache directory tags see https://bford.info/cachedir/
-"""
-            )
+""")
     except FileExistsError:
         pass
 
diff --git a/mypy/checkexpr.py b/mypy/checkexpr.py
@@ -2116,7 +2116,7 @@ def infer_function_type_arguments(
 
             if 2 in arg_pass_nums:
                 # Second pass of type inference.
-                (callee_type, inferred_args) = self.infer_function_type_arguments_pass2(
+                callee_type, inferred_args = self.infer_function_type_arguments_pass2(
                     callee_type,
                     args,
                     arg_kinds,
@@ -6462,7 +6462,7 @@ def try_parse_as_type_expression(self, maybe_type_expr: Expression) -> Type | No
         # Collect symbols targeted by NameExprs and MemberExprs,
         # to be looked up by TypeAnalyser when binding the
         # UnboundTypes corresponding to those expressions.
-        (name_exprs, member_exprs) = all_name_and_member_expressions(maybe_type_expr)
+        name_exprs, member_exprs = all_name_and_member_expressions(maybe_type_expr)
         sym_for_name = {e.name: SymbolTableNode(UNBOUND_IMPORTED, e.node) for e in name_exprs} | {
             e_name: SymbolTableNode(UNBOUND_IMPORTED, e.node)
             for e in member_exprs
diff --git a/mypy/checkpattern.py b/mypy/checkpattern.py
@@ -312,7 +312,7 @@ def visit_sequence_pattern(self, o: SequencePattern) -> PatternType:
             narrowed_inner_types = []
             inner_rest_types = []
             for inner_type, new_inner_type in zip(inner_types, new_inner_types):
-                (narrowed_inner_type, inner_rest_type) = (
+                narrowed_inner_type, inner_rest_type = (
                     self.chk.conditional_types_with_intersection(
                         inner_type, [get_type_range(new_inner_type)], o, default=inner_type
                     )
diff --git a/mypy/fastparse.py b/mypy/fastparse.py
@@ -634,7 +634,7 @@ def fix_function_overloads(self, stmts: list[Statement]) -> list[Statement]:
                 # Check IfStmt block to determine if function overloads can be merged
                 if_overload_name = self._check_ifstmt_for_overloads(stmt, current_overload_name)
                 if if_overload_name is not None:
-                    (if_block_with_overload, if_unknown_truth_value) = (
+                    if_block_with_overload, if_unknown_truth_value = (
                         self._get_executable_if_block_with_overloads(stmt)
                     )
 
diff --git a/mypy/messages.py b/mypy/messages.py
@@ -1295,17 +1295,13 @@ def argument_incompatible_with_supertype(
             )
 
     def comparison_method_example_msg(self, class_name: str) -> str:
-        return dedent(
-            """\
+        return dedent("""\
         It is recommended for "__eq__" to work with arbitrary objects, for example:
             def __eq__(self, other: object) -> bool:
                 if not isinstance(other, {class_name}):
                     return NotImplemented
                 return <logic to compare two {class_name} instances>
-        """.format(
-                class_name=class_name
-            )
-        )
+        """.format(class_name=class_name))
 
     def return_type_incompatible_with_supertype(
         self,
@@ -1802,7 +1798,7 @@ def redundant_cast(self, typ: Type, context: Context) -> None:
         )
 
     def assert_type_fail(self, source_type: Type, target_type: Type, context: Context) -> None:
-        (source, target) = format_type_distinctly(source_type, target_type, options=self.options)
+        source, target = format_type_distinctly(source_type, target_type, options=self.options)
         self.fail(f"Expression is of type {source}, not {target}", context, code=codes.ASSERT_TYPE)
 
     def unimported_type_becomes_any(self, prefix: str, typ: Type, ctx: Context) -> None:
diff --git a/mypy/report.py b/mypy/report.py
@@ -285,7 +285,7 @@ def _report_any_exprs(self) -> None:
         column_names = ["Name", "Anys", "Exprs", "Coverage"]
         rows: list[list[str]] = []
         for filename in sorted(self.counts):
-            (num_any, num_total) = self.counts[filename]
+            num_any, num_total = self.counts[filename]
             coverage = (float(num_total - num_any) / float(num_total)) * 100
             coverage_str = f"{coverage:.2f}%"
             rows.append([filename, str(num_any), str(num_total), coverage_str])
diff --git a/mypy/semanal_typeddict.py b/mypy/semanal_typeddict.py
@@ -162,7 +162,7 @@ def analyze_typeddict_classdef(self, defn: ClassDef) -> tuple[bool, TypeInfo | N
             self.add_keys_and_types_from_base(
                 base, field_types, required_keys, readonly_keys, defn
             )
-        (new_field_types, new_statements, new_required_keys, new_readonly_keys) = (
+        new_field_types, new_statements, new_required_keys, new_readonly_keys = (
             self.analyze_typeddict_classdef_fields(defn, oldfields=field_types)
         )
         if new_field_types is None:
diff --git a/mypy/test/meta/test_parse_data.py b/mypy/test/meta/test_parse_data.py
@@ -14,28 +14,24 @@ def _run_pytest(data_suite: str) -> PytestResult:
 class ParseTestDataSuite(Suite):
     def test_parse_invalid_case(self) -> None:
         # Act
-        result = _run_pytest(
-            """
+        result = _run_pytest("""
             [case abc]
             s: str
             [case foo-XFAIL]
             s: str
-            """
-        )
+            """)
 
         # Assert
         assert "Invalid testcase id 'foo-XFAIL'" in result.stdout
 
     def test_parse_invalid_section(self) -> None:
         # Act
-        result = _run_pytest(
-            """
+        result = _run_pytest("""
             [case abc]
             s: str
             [unknownsection]
             abc
-            """
-        )
+            """)
 
         # Assert
         expected_lineno = result.input.splitlines().index("[unknownsection]") + 1
@@ -46,14 +42,12 @@ def test_parse_invalid_section(self) -> None:
 
     def test_bad_ge_version_check(self) -> None:
         # Act
-        actual = _run_pytest(
-            """
+        actual = _run_pytest("""
             [case abc]
             s: str
             [out version>=3.10]
             abc
-            """
-        )
+            """)
 
         # Assert
         assert (
@@ -62,14 +56,12 @@ def test_bad_ge_version_check(self) -> None:
 
     def test_bad_eq_version_check(self) -> None:
         # Act
-        actual = _run_pytest(
-            """
+        actual = _run_pytest("""
             [case abc]
             s: str
             [out version==3.7]
             abc
-            """
-        )
+            """)
 
         # Assert
         assert (
diff --git a/mypy/test/meta/test_update_data.py b/mypy/test/meta/test_update_data.py
@@ -20,8 +20,7 @@ class UpdateDataSuite(Suite):
     def test_update_data(self) -> None:
         # Note: We test multiple testcases rather than 'test case per test case'
         #       so we could also exercise rewriting multiple testcases at once.
-        result = _run_pytest_update_data(
-            """
+        result = _run_pytest_update_data("""
             [case testCorrect]
             s: str = 42  # E: Incompatible types in assignment (expression has type "int", variable has type "str")
 
@@ -74,12 +73,10 @@ def test_update_data(self) -> None:
             [file b.py]
             s2: str = 43  # E: baz
             [builtins fixtures/list.pyi]
-            """
-        )
+            """)
 
         # Assert
-        expected = dedent_docstring(
-            """
+        expected = dedent_docstring("""
         [case testCorrect]
         s: str = 42  # E: Incompatible types in assignment (expression has type "int", variable has type "str")
 
@@ -130,6 +127,5 @@ def test_update_data(self) -> None:
         [file b.py]
         s2: str = 43  # E: Incompatible types in assignment (expression has type "int", variable has type "str")
         [builtins fixtures/list.pyi]
-        """
-        )
+        """)
         assert result.input_updated == expected
diff --git a/mypy/test/testreports.py b/mypy/test/testreports.py
@@ -42,8 +42,7 @@ def test_as_xml(self) -> None:
 
         cobertura_package.packages["raz"] = child_package
 
-        expected_output = textwrap.dedent(
-            """\
+        expected_output = textwrap.dedent("""\
             <package complexity="1.0" name="foobar" branch-rate="0" line-rate="0.5000">
               <classes/>
               <packages>
@@ -54,8 +53,7 @@ def test_as_xml(self) -> None:
                 </package>
               </packages>
             </package>
-        """
-        ).encode("ascii")
+        """).encode("ascii")
         assert_equal(
             expected_output, etree.tostring(cobertura_package.as_xml(), pretty_print=True)
         )
diff --git a/mypy/test/teststubtest.py b/mypy/test/teststubtest.py
@@ -2825,24 +2825,16 @@ def test_allowlist(self) -> None:
                 f.write("unused.*\n")
 
             output = run_stubtest(
-                stub=textwrap.dedent(
-                    """
+                stub=textwrap.dedent("""
                     def good() -> None: ...
                     def bad(number: int) -> None: ...
                     def also_bad(number: int) -> None: ...
-                    """.lstrip(
-                        "\n"
-                    )
-                ),
-                runtime=textwrap.dedent(
-                    """
+                    """.lstrip("\n")),
+                runtime=textwrap.dedent("""
                     def good(): pass
                     def bad(asdf): pass
                     def also_bad(asdf): pass
-                    """.lstrip(
-                        "\n"
-                    )
-                ),
+                    """.lstrip("\n")),
                 options=["--allowlist", allowlist.name, "--generate-allowlist"],
             )
             assert output == (
diff --git a/mypyc/ir/ops.py b/mypyc/ir/ops.py
@@ -1547,7 +1547,7 @@ def sources(self) -> list[Value]:
         return [self.lhs, self.rhs]
 
     def set_sources(self, new: list[Value]) -> None:
-        (self.lhs, self.rhs) = new
+        self.lhs, self.rhs = new
 
     def accept(self, visitor: OpVisitor[T]) -> T:
         return visitor.visit_float_op(self)
@@ -1605,7 +1605,7 @@ def sources(self) -> list[Value]:
         return [self.lhs, self.rhs]
 
     def set_sources(self, new: list[Value]) -> None:
-        (self.lhs, self.rhs) = new
+        self.lhs, self.rhs = new
 
     def accept(self, visitor: OpVisitor[T]) -> T:
         return visitor.visit_float_comparison_op(self)
diff --git a/mypyc/test/test_emit.py b/mypyc/test/test_emit.py
@@ -42,12 +42,9 @@ def test_reg(self) -> None:
 
     def test_object_annotation(self) -> None:
         assert self.emitter.object_annotation("hello, world", "line;") == " /* 'hello, world' */"
-        assert (
-            self.emitter.object_annotation(list(range(30)), "line;")
-            == """\
+        assert self.emitter.object_annotation(list(range(30)), "line;") == """\
  /* [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22,
          23, 24, 25, 26, 27, 28, 29] */"""
-        )
 
     def test_emit_line(self) -> None:
         emitter = self.emitter
@@ -60,12 +57,9 @@ def test_emit_line(self) -> None:
         emitter.emit_line("CPyStatics[0];", ann="hello, world")
         emitter.emit_line("CPyStatics[1];", ann=list(range(30)))
         assert emitter.fragments[0] == "CPyStatics[0]; /* 'hello, world' */\n"
-        assert (
-            emitter.fragments[1]
-            == """\
+        assert emitter.fragments[1] == """\
 CPyStatics[1]; /* [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20,
                   21, 22, 23, 24, 25, 26, 27, 28, 29] */\n"""
-        )
 
     def test_emit_undefined_value_for_simple_type(self) -> None:
         emitter = self.emitter

Original file line number	Diff line number	Diff line change
`@@ -312,7 +312,7 @@ def visit_sequence_pattern(self, o: SequencePattern) -> PatternType:`
`312`	`312`	`narrowed_inner_types = []`
`313`	`313`	`inner_rest_types = []`
`314`	`314`	`for inner_type, new_inner_type in zip(inner_types, new_inner_types):`
`315`		`- (narrowed_inner_type, inner_rest_type) = (`
	`315`	`+ narrowed_inner_type, inner_rest_type = (`
`316`	`316`	`self.chk.conditional_types_with_intersection(`
`317`	`317`	`inner_type, [get_type_range(new_inner_type)], o, default=inner_type`
`318`	`318`	`)`
Original file line number	Diff line number	Diff line change
`@@ -634,7 +634,7 @@ def fix_function_overloads(self, stmts: list[Statement]) -> list[Statement]:`
`634`	`634`	`# Check IfStmt block to determine if function overloads can be merged`
`635`	`635`	`if_overload_name = self._check_ifstmt_for_overloads(stmt, current_overload_name)`
`636`	`636`	`if if_overload_name is not None:`
`637`		`- (if_block_with_overload, if_unknown_truth_value) = (`
	`637`	`+ if_block_with_overload, if_unknown_truth_value = (`
`638`	`638`	`self._get_executable_if_block_with_overloads(stmt)`
`639`	`639`	`)`
`640`	`640`
Original file line number	Diff line number	Diff line change
`@@ -162,7 +162,7 @@ def analyze_typeddict_classdef(self, defn: ClassDef) -> tuple[bool, TypeInfo \| N`
`162`	`162`	`self.add_keys_and_types_from_base(`
`163`	`163`	`base, field_types, required_keys, readonly_keys, defn`
`164`	`164`	`)`
`165`		`- (new_field_types, new_statements, new_required_keys, new_readonly_keys) = (`
	`165`	`+ new_field_types, new_statements, new_required_keys, new_readonly_keys = (`
`166`	`166`	`self.analyze_typeddict_classdef_fields(defn, oldfields=field_types)`
`167`	`167`	`)`
`168`	`168`	`if new_field_types is None:`