Remove Python 2 support

.github/ISSUE_TEMPLATE/bug_report.md

@@ -16,7 +16,7 @@ current development version. To confirm this, you have three options:
 3. Or run _Black_ on your machine:
    - create a new virtualenv (make sure it's the same Python version);
    - clone this repository;
-   - run `pip install -e .[d,python2]`;
+   - run `pip install -e .[d]`;
    - run `pip install -r test_requirements.txt`
    - make sure it's sane by running `python -m pytest`; and
    - run `black` like you did last time.

CHANGES.md

@@ -4,6 +4,7 @@
 
 ### _Black_
 
+- **Remove Python 2 support** (#2740)
 - Do not accept bare carriage return line endings in pyproject.toml (#2408)
 - Improve error message for invalid regular expression (#2678)
 - Improve error message when parsing fails during AST safety check by embedding the

README.md

@@ -40,9 +40,7 @@ Try it out now using the [Black Playground](https://black.vercel.app). Watch the
 ### Installation
 
 _Black_ can be installed by running `pip install black`. It requires Python 3.6.2+ to
-run. If you want to format Python 2 code as well, install with
-`pip install black[python2]`. If you want to format Jupyter Notebooks, install with
-`pip install black[jupyter]`.
+run. If you want to format Jupyter Notebooks, install with `pip install black[jupyter]`.
 
 If you can't wait for the latest _hotness_ and want to install from GitHub, use:
 

action/main.py

@@ -14,7 +14,7 @@
 
 run([sys.executable, "-m", "venv", str(ENV_PATH)], check=True)
 
-req = "black[colorama,python2]"
+req = "black[colorama]"
 if VERSION:
     req += f"=={VERSION}"
 pip_proc = run(

docs/faq.md

@@ -75,16 +75,7 @@ disabled-by-default counterpart W504. E203 should be disabled while changes are
 
 ## Does Black support Python 2?
 
-```{warning}
-Python 2 support has been deprecated since 21.10b0.
-
-This support will be dropped in the first stable release, expected for January 2022.
-See [The Black Code Style](the_black_code_style/index.rst) for details.
-```
-
-For formatting, yes! [Install](getting_started.md#installation) with the `python2` extra
-to format Python 2 files too! In terms of running _Black_ though, Python 3.6 or newer is
-required.
+Support for formatting Python 2 code was removed in version 22.0.
 
 ## Why does my linter or typechecker complain after I format my code?
 
@@ -96,8 +87,7 @@ codebase with _Black_.
 
 ## Can I run Black with PyPy?
 
-Yes, there is support for PyPy 3.7 and higher. You cannot format Python 2 files under
-PyPy, because PyPy's inbuilt ast module does not support this.
+Yes, there is support for PyPy 3.7 and higher.
 
 ## Why does Black not detect syntax errors in my code?
 

docs/getting_started.md

@@ -17,9 +17,7 @@ Also, you can try out _Black_ online for minimal fuss on the
 ## Installation
 
 _Black_ can be installed by running `pip install black`. It requires Python 3.6.2+ to
-run, but can format Python 2 code too. Python 2 support needs the `typed_ast`
-dependency, which be installed with `pip install black[python2]`. If you want to format
-Jupyter Notebooks, install with `pip install black[jupyter]`.
+run. If you want to format Jupyter Notebooks, install with `pip install black[jupyter]`.
 
 If you can't wait for the latest _hotness_ and want to install from GitHub, use:
 

docs/integrations/github_actions.md

@@ -8,8 +8,8 @@ environment. Great for enforcing that your code matches the _Black_ code style.
 This action is known to support all GitHub-hosted runner OSes. In addition, only
 published versions of _Black_ are supported (i.e. whatever is available on PyPI).
 
-Finally, this action installs _Black_ with both the `colorama` and `python2` extras so
-the `--color` flag and formatting Python 2 code are supported.
+Finally, this action installs _Black_ with the `colorama` extra so the `--color` flag
+should work fine.
 
 ## Usage
 

docs/the_black_code_style/current_style.md

@@ -281,8 +281,7 @@ removed.
 
 _Black_ standardizes most numeric literals to use lowercase letters for the syntactic
 parts and uppercase letters for the digits themselves: `0xAB` instead of `0XAB` and
-`1e10` instead of `1E10`. Python 2 long literals are styled as `2L` instead of `2l` to
-avoid confusion between `l` and `1`.
+`1e10` instead of `1E10`.
 
 ### Line breaks & binary operators
 

pyproject.toml

@@ -29,7 +29,6 @@ build-backend = "setuptools.build_meta"
 [tool.pytest.ini_options]
 # Option below requires `tests/optional.py`
 optional-tests = [
-  "no_python2: run when `python2` extra NOT installed",
   "no_blackd: run when `d` extra NOT installed",
   "no_jupyter: run when `jupyter` extra NOT installed",
 ]

setup.py

@@ -112,7 +112,6 @@ def find_python_files(base: Path) -> List[Path]:
     extras_require={
         "d": ["aiohttp>=3.7.4"],
         "colorama": ["colorama>=0.4.3"],
-        "python2": ["typed-ast>=1.4.3"],
         "uvloop": ["uvloop>=0.15.2"],
         "jupyter": ["ipython>=7.8.0", "tokenize-rt>=3.2.0"],
     },

src/black/__init__.py

@@ -1083,20 +1083,8 @@ def f(
     else:
         versions = detect_target_versions(src_node, future_imports=future_imports)
 
-    # TODO: fully drop support and this code hopefully in January 2022 :D
-    if TargetVersion.PY27 in mode.target_versions or versions == {TargetVersion.PY27}:
-        msg = (
-            "DEPRECATION: Python 2 support will be removed in the first stable release "
-            "expected in January 2022."
-        )
-        err(msg, fg="yellow", bold=True)
-
     normalize_fmt_off(src_node)
-    lines = LineGenerator(
-        mode=mode,
-        remove_u_prefix="unicode_literals" in future_imports
-        or supports_feature(versions, Feature.UNICODE_LITERALS),
-    )
+    lines = LineGenerator(mode=mode)
     elt = EmptyLineTracker(is_pyi=mode.is_pyi)
     empty_line = Line(mode=mode)
     after = 0
@@ -1166,14 +1154,6 @@ def get_features_used(  # noqa: C901
             assert isinstance(n, Leaf)
             if "_" in n.value:
                 features.add(Feature.NUMERIC_UNDERSCORES)
-            elif n.value.endswith(("L", "l")):
-                # Python 2: 10L
-                features.add(Feature.LONG_INT_LITERAL)
-            elif len(n.value) >= 2 and n.value[0] == "0" and n.value[1].isdigit():
-                # Python 2: 0123; 00123; ...
-                if not all(char == "0" for char in n.value):
-                    # although we don't want to match 0000 or similar
-                    features.add(Feature.OCTAL_INT_LITERAL)
 
         elif n.type == token.SLASH:
             if n.parent and n.parent.type in {
@@ -1226,32 +1206,6 @@ def get_features_used(  # noqa: C901
         ):
             features.add(Feature.ANN_ASSIGN_EXTENDED_RHS)
 
-        # Python 2 only features (for its deprecation) except for integers, see above
-        elif n.type == syms.print_stmt:
-            features.add(Feature.PRINT_STMT)
-        elif n.type == syms.exec_stmt:
-            features.add(Feature.EXEC_STMT)
-        elif n.type == syms.tfpdef:
-            # def set_position((x, y), value):
-            #     ...
-            features.add(Feature.AUTOMATIC_PARAMETER_UNPACKING)
-        elif n.type == syms.except_clause:
-            # try:
-            #     ...
-            # except Exception, err:
-            #     ...
-            if len(n.children) >= 4:
-                if n.children[-2].type == token.COMMA:
-                    features.add(Feature.COMMA_STYLE_EXCEPT)
-        elif n.type == syms.raise_stmt:
-            # raise Exception, "msg"
-            if len(n.children) >= 4:
-                if n.children[-2].type == token.COMMA:
-                    features.add(Feature.COMMA_STYLE_RAISE)
-        elif n.type == token.BACKQUOTE:
-            # `i'm surprised this ever existed`
-            features.add(Feature.BACKQUOTE_REPR)
-
     return features
 
 

src/black/linegen.py

@@ -48,9 +48,8 @@ class LineGenerator(Visitor[Line]):
     in ways that will no longer stringify to valid Python code on the tree.
     """
 
-    def __init__(self, mode: Mode, remove_u_prefix: bool = False) -> None:
+    def __init__(self, mode: Mode) -> None:
         self.mode = mode
-        self.remove_u_prefix = remove_u_prefix
         self.current_line: Line
         self.__post_init__()
 
@@ -92,9 +91,7 @@ def visit_default(self, node: LN) -> Iterator[Line]:
 
             normalize_prefix(node, inside_brackets=any_open_brackets)
             if self.mode.string_normalization and node.type == token.STRING:
-                node.value = normalize_string_prefix(
-                    node.value, remove_u_prefix=self.remove_u_prefix
-                )
+                node.value = normalize_string_prefix(node.value)
                 node.value = normalize_string_quotes(node.value)
             if node.type == token.NUMBER:
                 normalize_numeric_literal(node)
@@ -236,7 +233,7 @@ def visit_STRING(self, leaf: Leaf) -> Iterator[Line]:
         if is_docstring(leaf) and "\\\n" not in leaf.value:
             # We're ignoring docstrings with backslash newline escapes because changing
             # indentation of those changes the AST representation of the code.
-            docstring = normalize_string_prefix(leaf.value, self.remove_u_prefix)
+            docstring = normalize_string_prefix(leaf.value)
             prefix = get_string_prefix(docstring)
             docstring = docstring[len(prefix) :]  # Remove the prefix
             quote_char = docstring[0]

src/black/mode.py

@@ -20,7 +20,6 @@
 
 
 class TargetVersion(Enum):
-    PY27 = 2
     PY33 = 3
     PY34 = 4
     PY35 = 5
@@ -30,13 +29,8 @@ class TargetVersion(Enum):
     PY39 = 9
     PY310 = 10
 
-    def is_python2(self) -> bool:
-        return self is TargetVersion.PY27
-
 
 class Feature(Enum):
-    # All string literals are unicode
-    UNICODE_LITERALS = 1
     F_STRINGS = 2
     NUMERIC_UNDERSCORES = 3
     TRAILING_COMMA_IN_CALL = 4
@@ -56,51 +50,24 @@ class Feature(Enum):
     # __future__ flags
     FUTURE_ANNOTATIONS = 51
 
-    # temporary for Python 2 deprecation
-    PRINT_STMT = 200
-    EXEC_STMT = 201
-    AUTOMATIC_PARAMETER_UNPACKING = 202
-    COMMA_STYLE_EXCEPT = 203
-    COMMA_STYLE_RAISE = 204
-    LONG_INT_LITERAL = 205
-    OCTAL_INT_LITERAL = 206
-    BACKQUOTE_REPR = 207
-
 
 FUTURE_FLAG_TO_FEATURE: Final = {
     "annotations": Feature.FUTURE_ANNOTATIONS,
 }
 
 
 VERSION_TO_FEATURES: Dict[TargetVersion, Set[Feature]] = {
-    TargetVersion.PY27: {
-        Feature.ASYNC_IDENTIFIERS,
-        Feature.PRINT_STMT,
-        Feature.EXEC_STMT,
-        Feature.AUTOMATIC_PARAMETER_UNPACKING,
-        Feature.COMMA_STYLE_EXCEPT,
-        Feature.COMMA_STYLE_RAISE,
-        Feature.LONG_INT_LITERAL,
-        Feature.OCTAL_INT_LITERAL,
-        Feature.BACKQUOTE_REPR,
-    },
-    TargetVersion.PY33: {Feature.UNICODE_LITERALS, Feature.ASYNC_IDENTIFIERS},
-    TargetVersion.PY34: {Feature.UNICODE_LITERALS, Feature.ASYNC_IDENTIFIERS},
-    TargetVersion.PY35: {
-        Feature.UNICODE_LITERALS,
-        Feature.TRAILING_COMMA_IN_CALL,
-        Feature.ASYNC_IDENTIFIERS,
-    },
+    TargetVersion.PY33: {Feature.ASYNC_IDENTIFIERS},
+    TargetVersion.PY34: {Feature.ASYNC_IDENTIFIERS},
+    TargetVersion.PY35: {Feature.TRAILING_COMMA_IN_CALL, Feature.ASYNC_IDENTIFIERS},
     TargetVersion.PY36: {
-        Feature.UNICODE_LITERALS,
         Feature.F_STRINGS,
         Feature.NUMERIC_UNDERSCORES,
         Feature.TRAILING_COMMA_IN_CALL,
         Feature.TRAILING_COMMA_IN_DEF,
         Feature.ASYNC_IDENTIFIERS,
     },
     TargetVersion.PY37: {
-        Feature.UNICODE_LITERALS,
         Feature.F_STRINGS,
         Feature.NUMERIC_UNDERSCORES,
         Feature.TRAILING_COMMA_IN_CALL,
@@ -109,7 +76,6 @@ class Feature(Enum):
         Feature.FUTURE_ANNOTATIONS,
     },
     TargetVersion.PY38: {
-        Feature.UNICODE_LITERALS,
         Feature.F_STRINGS,
         Feature.NUMERIC_UNDERSCORES,
         Feature.TRAILING_COMMA_IN_CALL,
@@ -122,7 +88,6 @@ class Feature(Enum):
         Feature.ANN_ASSIGN_EXTENDED_RHS,
     },
     TargetVersion.PY39: {
-        Feature.UNICODE_LITERALS,
         Feature.F_STRINGS,
         Feature.NUMERIC_UNDERSCORES,
         Feature.TRAILING_COMMA_IN_CALL,
@@ -136,7 +101,6 @@ class Feature(Enum):
         Feature.ANN_ASSIGN_EXTENDED_RHS,
     },
     TargetVersion.PY310: {
-        Feature.UNICODE_LITERALS,
         Feature.F_STRINGS,
         Feature.NUMERIC_UNDERSCORES,
         Feature.TRAILING_COMMA_IN_CALL,

src/black/nodes.py

@@ -259,16 +259,6 @@ def whitespace(leaf: Leaf, *, complex_subscript: bool) -> str:  # noqa: C901
         ):
             return NO
 
-        elif (
-            prevp.type == token.RIGHTSHIFT
-            and prevp.parent
-            and prevp.parent.type == syms.shift_expr
-            and prevp.prev_sibling
-            and is_name_token(prevp.prev_sibling)
-            and prevp.prev_sibling.value == "print"
-        ):
-            # Python 2 print chevron
-            return NO
         elif prevp.type == token.AT and p.parent and p.parent.type == syms.decorator:
             # no space in decorators
             return NO

src/black/numerics.py

@@ -25,13 +25,10 @@ def format_scientific_notation(text: str) -> str:
     return f"{before}e{sign}{after}"
 
 
-def format_long_or_complex_number(text: str) -> str:
-    """Formats a long or complex string like `10L` or `10j`"""
+def format_complex_number(text: str) -> str:
+    """Formats a complex string like `10j`"""
     number = text[:-1]
     suffix = text[-1]
-    # Capitalize in "2L" because "l" looks too similar to "1".
-    if suffix == "l":
-        suffix = "L"
     return f"{format_float_or_int_string(number)}{suffix}"
 
 
@@ -47,9 +44,7 @@ def format_float_or_int_string(text: str) -> str:
 def normalize_numeric_literal(leaf: Leaf) -> None:
     """Normalizes numeric (float, int, and complex) literals.
 
-    All letters used in the representation are normalized to lowercase (except
-    in Python 2 long literals).
-    """
+    All letters used in the representation are normalized to lowercase."""
     text = leaf.value.lower()
     if text.startswith(("0o", "0b")):
         # Leave octal and binary literals alone.
@@ -58,8 +53,8 @@ def normalize_numeric_literal(leaf: Leaf) -> None:
         text = format_hex(text)
     elif "e" in text:
         text = format_scientific_notation(text)
-    elif text.endswith(("j", "l")):
-        text = format_long_or_complex_number(text)
+    elif text.endswith("j"):
+        text = format_complex_number(text)
     else:
         text = format_float_or_int_string(text)
     leaf.value = text