[pre-commit.ci] pre-commit autoupdate (#3825)

[etc/vim.git] / src / black / parsing.py

diff --git a/src/black/parsing.py b/src/black/parsing.py
index 8e9feea9120db796afdf980b10ddc5e7864cebd0..e98e019cac6e9a1955f91cc35553a1b7393951dd 100644 (file)
--- a/src/black/parsing.py
+++ b/src/black/parsing.py
@@ -3,31 +3,18 @@ Parse Python code and perform AST validation.
 """
 import ast
 import sys
 """
 import ast
 import sys

-from typing import Iterable, Iterator, List, Set, Union
+from typing import Final, Iterable, Iterator, List, Set, Tuple

 
 

-# lib2to3 fork
-from blib2to3.pytree import Node, Leaf
-from blib2to3 import pygram, pytree
+from black.mode import VERSION_TO_FEATURES, Feature, TargetVersion, supports_feature
+from black.nodes import syms
+from blib2to3 import pygram

 from blib2to3.pgen2 import driver
 from blib2to3.pgen2.grammar import Grammar
 from blib2to3.pgen2.parse import ParseError
 from blib2to3.pgen2 import driver
 from blib2to3.pgen2.grammar import Grammar
 from blib2to3.pgen2.parse import ParseError

+from blib2to3.pgen2.tokenize import TokenError
+from blib2to3.pytree import Leaf, Node

 
 

-from black.mode import TargetVersion, Feature, supports_feature
-from black.nodes import syms
-
-try:
-    from typed_ast import ast3, ast27
-except ImportError:
-    if sys.version_info < (3, 8):
-        print(
-            "The typed_ast package is required but not installed.\n"
-            "You can upgrade to Python 3.8+ or install typed_ast with\n"
-            "`python3 -m pip install typed-ast`.",
-            file=sys.stderr,
-        )
-        sys.exit(1)
-    else:
-        ast3 = ast27 = ast
+PY2_HINT: Final = "Python 2 support was removed in version 22.0."

 
 
 class InvalidInput(ValueError):
 
 
 class InvalidInput(ValueError):


@@ -38,36 +25,30 @@ def get_grammars(target_versions: Set[TargetVersion]) -> List[Grammar]:
     if not target_versions:
         # No target_version specified, so try all grammars.
         return [
     if not target_versions:
         # No target_version specified, so try all grammars.
         return [

-            # Python 3.7+
+            # Python 3.7-3.9

             pygram.python_grammar_no_print_statement_no_exec_statement_async_keywords,
             # Python 3.0-3.6
             pygram.python_grammar_no_print_statement_no_exec_statement,
             pygram.python_grammar_no_print_statement_no_exec_statement_async_keywords,
             # Python 3.0-3.6
             pygram.python_grammar_no_print_statement_no_exec_statement,

-            # Python 2.7 with future print_function import
-            pygram.python_grammar_no_print_statement,
-            # Python 2.7
-            pygram.python_grammar,
+            # Python 3.10+
+            pygram.python_grammar_soft_keywords,

         ]
 
         ]
 

-    if all(version.is_python2() for version in target_versions):
-        # Python 2-only code, so try Python 2 grammars.
-        return [
-            # Python 2.7 with future print_function import
-            pygram.python_grammar_no_print_statement,
-            # Python 2.7
-            pygram.python_grammar,
-        ]
-
-    # Python 3-compatible code, so only try Python 3 grammar.

     grammars = []
     # If we have to parse both, try to parse async as a keyword first
     grammars = []
     # If we have to parse both, try to parse async as a keyword first

-    if not supports_feature(target_versions, Feature.ASYNC_IDENTIFIERS):
-        # Python 3.7+
+    if not supports_feature(
+        target_versions, Feature.ASYNC_IDENTIFIERS
+    ) and not supports_feature(target_versions, Feature.PATTERN_MATCHING):
+        # Python 3.7-3.9

         grammars.append(
             pygram.python_grammar_no_print_statement_no_exec_statement_async_keywords
         )
     if not supports_feature(target_versions, Feature.ASYNC_KEYWORDS):
         # Python 3.0-3.6
         grammars.append(pygram.python_grammar_no_print_statement_no_exec_statement)
         grammars.append(
             pygram.python_grammar_no_print_statement_no_exec_statement_async_keywords
         )
     if not supports_feature(target_versions, Feature.ASYNC_KEYWORDS):
         # Python 3.0-3.6
         grammars.append(pygram.python_grammar_no_print_statement_no_exec_statement)

+    if any(Feature.PATTERN_MATCHING in VERSION_TO_FEATURES[v] for v in target_versions):
+        # Python 3.10+
+        grammars.append(pygram.python_grammar_soft_keywords)
+

     # At least one of the above branches must have been taken, because every Python
     # version has exactly one of the two 'ASYNC_*' flags
     return grammars
     # At least one of the above branches must have been taken, because every Python
     # version has exactly one of the two 'ASYNC_*' flags
     return grammars


@@ -78,8 +59,10 @@ def lib2to3_parse(src_txt: str, target_versions: Iterable[TargetVersion] = ()) -
     if not src_txt.endswith("\n"):
         src_txt += "\n"
 
     if not src_txt.endswith("\n"):
         src_txt += "\n"
 

-    for grammar in get_grammars(set(target_versions)):
-        drv = driver.Driver(grammar, pytree.convert)
+    grammars = get_grammars(set(target_versions))
+    errors = {}
+    for grammar in grammars:
+        drv = driver.Driver(grammar)

         try:
             result = drv.parse_string(src_txt, True)
             break
         try:
             result = drv.parse_string(src_txt, True)
             break


@@ -91,8 +74,29 @@ def lib2to3_parse(src_txt: str, target_versions: Iterable[TargetVersion] = ()) -
                 faulty_line = lines[lineno - 1]
             except IndexError:
                 faulty_line = "<line number missing in source>"
                 faulty_line = lines[lineno - 1]
             except IndexError:
                 faulty_line = "<line number missing in source>"

-            exc = InvalidInput(f"Cannot parse: {lineno}:{column}: {faulty_line}")
+            errors[grammar.version] = InvalidInput(
+                f"Cannot parse: {lineno}:{column}: {faulty_line}"
+            )
+
+        except TokenError as te:
+            # In edge cases these are raised; and typically don't have a "faulty_line".
+            lineno, column = te.args[1]
+            errors[grammar.version] = InvalidInput(
+                f"Cannot parse: {lineno}:{column}: {te.args[0]}"
+            )
+

     else:
     else:

+        # Choose the latest version when raising the actual parsing error.
+        assert len(errors) >= 1
+        exc = errors[max(errors)]
+
+        if matches_grammar(src_txt, pygram.python_grammar) or matches_grammar(
+            src_txt, pygram.python_grammar_no_print_statement
+        ):
+            original_msg = exc.args[0]
+            msg = f"{original_msg}\n{PY2_HINT}"
+            raise InvalidInput(msg) from None
+

         raise exc from None
 
     if isinstance(result, Leaf):
         raise exc from None
 
     if isinstance(result, Leaf):


@@ -100,55 +104,85 @@ def lib2to3_parse(src_txt: str, target_versions: Iterable[TargetVersion] = ()) -
     return result
 
 
     return result
 
 

+def matches_grammar(src_txt: str, grammar: Grammar) -> bool:
+    drv = driver.Driver(grammar)
+    try:
+        drv.parse_string(src_txt, True)
+    except (ParseError, TokenError, IndentationError):
+        return False
+    else:
+        return True
+
+

 def lib2to3_unparse(node: Node) -> str:
     """Given a lib2to3 node, return its string representation."""
     code = str(node)
     return code
 
 
 def lib2to3_unparse(node: Node) -> str:
     """Given a lib2to3 node, return its string representation."""
     code = str(node)
     return code
 
 

-def parse_ast(src: str) -> Union[ast.AST, ast3.AST, ast27.AST]:
+def parse_single_version(
+    src: str, version: Tuple[int, int], *, type_comments: bool
+) -> ast.AST:

     filename = "<unknown>"
     filename = "<unknown>"

-    if sys.version_info >= (3, 8):
-        # TODO: support Python 4+ ;)
-        for minor_version in range(sys.version_info[1], 4, -1):
-            try:
-                return ast.parse(src, filename, feature_version=(3, minor_version))
-            except SyntaxError:
-                continue
-    else:
-        for feature_version in (7, 6):
-            try:
-                return ast3.parse(src, filename, feature_version=feature_version)
-            except SyntaxError:
-                continue
-    if ast27.__name__ == "ast":
-        raise SyntaxError(
-            "The requested source code has invalid Python 3 syntax.\n"
-            "If you are trying to format Python 2 files please reinstall Black"
-            " with the 'python2' extra: `python3 -m pip install black[python2]`."
-        )
-    return ast27.parse(src)
+    return ast.parse(
+        src, filename, feature_version=version, type_comments=type_comments
+    )
+
+
+def parse_ast(src: str) -> ast.AST:
+    # TODO: support Python 4+ ;)
+    versions = [(3, minor) for minor in range(3, sys.version_info[1] + 1)]
+
+    first_error = ""
+    for version in sorted(versions, reverse=True):
+        try:
+            return parse_single_version(src, version, type_comments=True)
+        except SyntaxError as e:
+            if not first_error:
+                first_error = str(e)
+
+    # Try to parse without type comments
+    for version in sorted(versions, reverse=True):
+        try:
+            return parse_single_version(src, version, type_comments=False)
+        except SyntaxError:
+            pass

 
 

+    raise SyntaxError(first_error)

 
 

-def stringify_ast(
-    node: Union[ast.AST, ast3.AST, ast27.AST], depth: int = 0
-) -> Iterator[str]:
+
+def _normalize(lineend: str, value: str) -> str:
+    # To normalize, we strip any leading and trailing space from
+    # each line...
+    stripped: List[str] = [i.strip() for i in value.splitlines()]
+    normalized = lineend.join(stripped)
+    # ...and remove any blank lines at the beginning and end of
+    # the whole string
+    return normalized.strip()
+
+
+def stringify_ast(node: ast.AST, depth: int = 0) -> Iterator[str]:

     """Simple visitor generating strings to compare ASTs by content."""
 
     """Simple visitor generating strings to compare ASTs by content."""
 

-    node = fixup_ast_constants(node)
+    if (
+        isinstance(node, ast.Constant)
+        and isinstance(node.value, str)
+        and node.kind == "u"
+    ):
+        # It's a quirk of history that we strip the u prefix over here. We used to
+        # rewrite the AST nodes for Python version compatibility and we never copied
+        # over the kind
+        node.kind = None

 
     yield f"{'  ' * depth}{node.__class__.__name__}("
 
     for field in sorted(node._fields):  # noqa: F402
         # TypeIgnore has only one field 'lineno' which breaks this comparison
 
     yield f"{'  ' * depth}{node.__class__.__name__}("
 
     for field in sorted(node._fields):  # noqa: F402
         # TypeIgnore has only one field 'lineno' which breaks this comparison

-        type_ignore_classes = (ast3.TypeIgnore, ast27.TypeIgnore)
-        if sys.version_info >= (3, 8):
-            type_ignore_classes += (ast.TypeIgnore,)
-        if isinstance(node, type_ignore_classes):
+        if isinstance(node, ast.TypeIgnore):

             break
 
         try:
             break
 
         try:

-            value = getattr(node, field)
+            value: object = getattr(node, field)

         except AttributeError:
             continue
 
         except AttributeError:
             continue
 


@@ -160,56 +194,34 @@ def stringify_ast(
                 # parentheses and they change the AST.
                 if (
                     field == "targets"
                 # parentheses and they change the AST.
                 if (
                     field == "targets"

-                    and isinstance(node, (ast.Delete, ast3.Delete, ast27.Delete))
-                    and isinstance(item, (ast.Tuple, ast3.Tuple, ast27.Tuple))
+                    and isinstance(node, ast.Delete)
+                    and isinstance(item, ast.Tuple)

                 ):
                 ):

-                    for item in item.elts:
-                        yield from stringify_ast(item, depth + 2)
+                    for elt in item.elts:
+                        yield from stringify_ast(elt, depth + 2)

 
 

-                elif isinstance(item, (ast.AST, ast3.AST, ast27.AST)):
+                elif isinstance(item, ast.AST):

                     yield from stringify_ast(item, depth + 2)
 
                     yield from stringify_ast(item, depth + 2)
 

-        elif isinstance(value, (ast.AST, ast3.AST, ast27.AST)):
+        elif isinstance(value, ast.AST):

             yield from stringify_ast(value, depth + 2)
 
         else:
             yield from stringify_ast(value, depth + 2)
 
         else:

-            # Constant strings may be indented across newlines, if they are
-            # docstrings; fold spaces after newlines when comparing. Similarly,
-            # trailing and leading space may be removed.
-            # Note that when formatting Python 2 code, at least with Windows
-            # line-endings, docstrings can end up here as bytes instead of
-            # str so make sure that we handle both cases.
+            normalized: object

             if (
                 isinstance(node, ast.Constant)
                 and field == "value"
             if (
                 isinstance(node, ast.Constant)
                 and field == "value"

-                and isinstance(value, (str, bytes))
+                and isinstance(value, str)

             ):
             ):

-                lineend = "\n" if isinstance(value, str) else b"\n"
-                # To normalize, we strip any leading and trailing space from
-                # each line...
-                stripped = [line.strip() for line in value.splitlines()]
-                normalized = lineend.join(stripped)  # type: ignore[attr-defined]
-                # ...and remove any blank lines at the beginning and end of
-                # the whole string
-                normalized = normalized.strip()
+                # Constant strings may be indented across newlines, if they are
+                # docstrings; fold spaces after newlines when comparing. Similarly,
+                # trailing and leading space may be removed.
+                normalized = _normalize("\n", value)
+            elif field == "type_comment" and isinstance(value, str):
+                # Trailing whitespace in type comments is removed.
+                normalized = value.rstrip()

             else:
                 normalized = value
             yield f"{'  ' * (depth+2)}{normalized!r},  # {value.__class__.__name__}"
 
     yield f"{'  ' * depth})  # /{node.__class__.__name__}"
             else:
                 normalized = value
             yield f"{'  ' * (depth+2)}{normalized!r},  # {value.__class__.__name__}"
 
     yield f"{'  ' * depth})  # /{node.__class__.__name__}"

-
-
-def fixup_ast_constants(
-    node: Union[ast.AST, ast3.AST, ast27.AST]
-) -> Union[ast.AST, ast3.AST, ast27.AST]:
-    """Map ast nodes deprecated in 3.8 to Constant."""
-    if isinstance(node, (ast.Str, ast3.Str, ast27.Str, ast.Bytes, ast3.Bytes)):
-        return ast.Constant(value=node.s)
-
-    if isinstance(node, (ast.Num, ast3.Num, ast27.Num)):
-        return ast.Constant(value=node.n)
-
-    if isinstance(node, (ast.NameConstant, ast3.NameConstant)):
-        return ast.Constant(value=node.value)
-
-    return node