init

.venv/lib/python3.8/site-packages/black/mode.py

@@ -0,0 +1,188 @@
+"""Data structures configuring Black behavior.
+
+Mostly around Python language feature support per version and Black configuration
+chosen by the user.
+"""
+
+from hashlib import sha256
+import sys
+
+from dataclasses import dataclass, field
+from enum import Enum, auto
+from operator import attrgetter
+from typing import Dict, Set
+from warnings import warn
+
+if sys.version_info < (3, 8):
+    from typing_extensions import Final
+else:
+    from typing import Final
+
+from black.const import DEFAULT_LINE_LENGTH
+
+
+class TargetVersion(Enum):
+    PY33 = 3
+    PY34 = 4
+    PY35 = 5
+    PY36 = 6
+    PY37 = 7
+    PY38 = 8
+    PY39 = 9
+    PY310 = 10
+
+
+class Feature(Enum):
+    F_STRINGS = 2
+    NUMERIC_UNDERSCORES = 3
+    TRAILING_COMMA_IN_CALL = 4
+    TRAILING_COMMA_IN_DEF = 5
+    # The following two feature-flags are mutually exclusive, and exactly one should be
+    # set for every version of python.
+    ASYNC_IDENTIFIERS = 6
+    ASYNC_KEYWORDS = 7
+    ASSIGNMENT_EXPRESSIONS = 8
+    POS_ONLY_ARGUMENTS = 9
+    RELAXED_DECORATORS = 10
+    PATTERN_MATCHING = 11
+    UNPACKING_ON_FLOW = 12
+    ANN_ASSIGN_EXTENDED_RHS = 13
+    FORCE_OPTIONAL_PARENTHESES = 50
+
+    # __future__ flags
+    FUTURE_ANNOTATIONS = 51
+
+
+FUTURE_FLAG_TO_FEATURE: Final = {
+    "annotations": Feature.FUTURE_ANNOTATIONS,
+}
+
+
+VERSION_TO_FEATURES: Dict[TargetVersion, Set[Feature]] = {
+    TargetVersion.PY33: {Feature.ASYNC_IDENTIFIERS},
+    TargetVersion.PY34: {Feature.ASYNC_IDENTIFIERS},
+    TargetVersion.PY35: {Feature.TRAILING_COMMA_IN_CALL, Feature.ASYNC_IDENTIFIERS},
+    TargetVersion.PY36: {
+        Feature.F_STRINGS,
+        Feature.NUMERIC_UNDERSCORES,
+        Feature.TRAILING_COMMA_IN_CALL,
+        Feature.TRAILING_COMMA_IN_DEF,
+        Feature.ASYNC_IDENTIFIERS,
+    },
+    TargetVersion.PY37: {
+        Feature.F_STRINGS,
+        Feature.NUMERIC_UNDERSCORES,
+        Feature.TRAILING_COMMA_IN_CALL,
+        Feature.TRAILING_COMMA_IN_DEF,
+        Feature.ASYNC_KEYWORDS,
+        Feature.FUTURE_ANNOTATIONS,
+    },
+    TargetVersion.PY38: {
+        Feature.F_STRINGS,
+        Feature.NUMERIC_UNDERSCORES,
+        Feature.TRAILING_COMMA_IN_CALL,
+        Feature.TRAILING_COMMA_IN_DEF,
+        Feature.ASYNC_KEYWORDS,
+        Feature.FUTURE_ANNOTATIONS,
+        Feature.ASSIGNMENT_EXPRESSIONS,
+        Feature.POS_ONLY_ARGUMENTS,
+        Feature.UNPACKING_ON_FLOW,
+        Feature.ANN_ASSIGN_EXTENDED_RHS,
+    },
+    TargetVersion.PY39: {
+        Feature.F_STRINGS,
+        Feature.NUMERIC_UNDERSCORES,
+        Feature.TRAILING_COMMA_IN_CALL,
+        Feature.TRAILING_COMMA_IN_DEF,
+        Feature.ASYNC_KEYWORDS,
+        Feature.FUTURE_ANNOTATIONS,
+        Feature.ASSIGNMENT_EXPRESSIONS,
+        Feature.RELAXED_DECORATORS,
+        Feature.POS_ONLY_ARGUMENTS,
+        Feature.UNPACKING_ON_FLOW,
+        Feature.ANN_ASSIGN_EXTENDED_RHS,
+    },
+    TargetVersion.PY310: {
+        Feature.F_STRINGS,
+        Feature.NUMERIC_UNDERSCORES,
+        Feature.TRAILING_COMMA_IN_CALL,
+        Feature.TRAILING_COMMA_IN_DEF,
+        Feature.ASYNC_KEYWORDS,
+        Feature.FUTURE_ANNOTATIONS,
+        Feature.ASSIGNMENT_EXPRESSIONS,
+        Feature.RELAXED_DECORATORS,
+        Feature.POS_ONLY_ARGUMENTS,
+        Feature.UNPACKING_ON_FLOW,
+        Feature.ANN_ASSIGN_EXTENDED_RHS,
+        Feature.PATTERN_MATCHING,
+    },
+}
+
+
+def supports_feature(target_versions: Set[TargetVersion], feature: Feature) -> bool:
+    return all(feature in VERSION_TO_FEATURES[version] for version in target_versions)
+
+
+class Preview(Enum):
+    """Individual preview style features."""
+
+    string_processing = auto()
+    remove_redundant_parens = auto()
+    one_element_subscript = auto()
+
+
+class Deprecated(UserWarning):
+    """Visible deprecation warning."""
+
+
+@dataclass
+class Mode:
+    target_versions: Set[TargetVersion] = field(default_factory=set)
+    line_length: int = DEFAULT_LINE_LENGTH
+    string_normalization: bool = True
+    is_pyi: bool = False
+    is_ipynb: bool = False
+    magic_trailing_comma: bool = True
+    experimental_string_processing: bool = False
+    python_cell_magics: Set[str] = field(default_factory=set)
+    preview: bool = False
+
+    def __post_init__(self) -> None:
+        if self.experimental_string_processing:
+            warn(
+                "`experimental string processing` has been included in `preview`"
+                " and deprecated. Use `preview` instead.",
+                Deprecated,
+            )
+
+    def __contains__(self, feature: Preview) -> bool:
+        """
+        Provide `Preview.FEATURE in Mode` syntax that mirrors the ``preview`` flag.
+
+        The argument is not checked and features are not differentiated.
+        They only exist to make development easier by clarifying intent.
+        """
+        if feature is Preview.string_processing:
+            return self.preview or self.experimental_string_processing
+        return self.preview
+
+    def get_cache_key(self) -> str:
+        if self.target_versions:
+            version_str = ",".join(
+                str(version.value)
+                for version in sorted(self.target_versions, key=attrgetter("value"))
+            )
+        else:
+            version_str = "-"
+        parts = [
+            version_str,
+            str(self.line_length),
+            str(int(self.string_normalization)),
+            str(int(self.is_pyi)),
+            str(int(self.is_ipynb)),
+            str(int(self.magic_trailing_comma)),
+            str(int(self.experimental_string_processing)),
+            str(int(self.preview)),
+            sha256((",".join(sorted(self.python_cell_magics))).encode()).hexdigest(),
+        ]
+        return ".".join(parts)