mirror of
https://github.com/pre-commit/pre-commit-hooks.git
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1386 lines
54 KiB
Python
1386 lines
54 KiB
Python
# Licensed under the Apache License: http://www.apache.org/licenses/LICENSE-2.0
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# For details: https://github.com/nedbat/coveragepy/blob/master/NOTICE.txt
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"""Code parsing for coverage.py."""
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from __future__ import annotations
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import ast
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import collections
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import os
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import re
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import sys
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import token
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import tokenize
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from dataclasses import dataclass
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from types import CodeType
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from typing import Any
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from typing import Callable
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from typing import cast
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from typing import Dict
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from typing import Iterable
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from typing import List
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from typing import Optional
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from typing import Protocol
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from typing import Sequence
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from typing import Set
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from typing import Tuple
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from coverage import env
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from coverage.bytecode import code_objects
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from coverage.debug import short_stack
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from coverage.exceptions import NoSource
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from coverage.exceptions import NotPython
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from coverage.misc import join_regex
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from coverage.misc import nice_pair
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from coverage.phystokens import generate_tokens
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from coverage.types import TArc
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from coverage.types import TLineNo
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class PythonParser:
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"""Parse code to find executable lines, excluded lines, etc.
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This information is all based on static analysis: no code execution is
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involved.
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"""
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def __init__(
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self,
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text: str | None = None,
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filename: str | None = None,
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exclude: str | None = None,
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) -> None:
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"""
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Source can be provided as `text`, the text itself, or `filename`, from
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which the text will be read. Excluded lines are those that match
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`exclude`, a regex string.
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"""
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assert text or filename, 'PythonParser needs either text or filename'
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self.filename = filename or '<code>'
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if text is not None:
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self.text: str = text
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else:
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from coverage.python import get_python_source
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try:
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self.text = get_python_source(self.filename)
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except OSError as err:
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raise NoSource(f"No source for code: '{self.filename}': {err}") from err
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self.exclude = exclude
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# The text lines of the parsed code.
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self.lines: list[str] = self.text.split('\n')
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# The normalized line numbers of the statements in the code. Exclusions
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# are taken into account, and statements are adjusted to their first
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# lines.
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self.statements: set[TLineNo] = set()
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# The normalized line numbers of the excluded lines in the code,
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# adjusted to their first lines.
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self.excluded: set[TLineNo] = set()
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# The raw_* attributes are only used in this class, and in
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# lab/parser.py to show how this class is working.
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# The line numbers that start statements, as reported by the line
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# number table in the bytecode.
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self.raw_statements: set[TLineNo] = set()
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# The raw line numbers of excluded lines of code, as marked by pragmas.
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self.raw_excluded: set[TLineNo] = set()
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# The line numbers of class definitions.
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self.raw_classdefs: set[TLineNo] = set()
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# The line numbers of docstring lines.
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self.raw_docstrings: set[TLineNo] = set()
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# Internal detail, used by lab/parser.py.
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self.show_tokens = False
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# A dict mapping line numbers to lexical statement starts for
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# multi-line statements.
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self._multiline: dict[TLineNo, TLineNo] = {}
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# Lazily-created arc data, and missing arc descriptions.
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self._all_arcs: set[TArc] | None = None
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self._missing_arc_fragments: TArcFragments | None = None
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def lines_matching(self, *regexes: str) -> set[TLineNo]:
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"""Find the lines matching one of a list of regexes.
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Returns a set of line numbers, the lines that contain a match for one
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of the regexes in `regexes`. The entire line needn't match, just a
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part of it.
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"""
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combined = join_regex(regexes)
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regex_c = re.compile(combined)
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matches = set()
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for i, ltext in enumerate(self.lines, start=1):
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if regex_c.search(ltext):
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matches.add(i)
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return matches
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def _raw_parse(self) -> None:
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"""Parse the source to find the interesting facts about its lines.
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A handful of attributes are updated.
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"""
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# Find lines which match an exclusion pattern.
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if self.exclude:
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self.raw_excluded = self.lines_matching(self.exclude)
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# Tokenize, to find excluded suites, to find docstrings, and to find
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# multi-line statements.
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# The last token seen. Start with INDENT to get module docstrings
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prev_toktype: int = token.INDENT
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# The current number of indents.
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indent: int = 0
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# An exclusion comment will exclude an entire clause at this indent.
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exclude_indent: int = 0
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# Are we currently excluding lines?
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excluding: bool = False
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# Are we excluding decorators now?
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excluding_decorators: bool = False
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# The line number of the first line in a multi-line statement.
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first_line: int = 0
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# Is the file empty?
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empty: bool = True
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# Is this the first token on a line?
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first_on_line: bool = True
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# Parenthesis (and bracket) nesting level.
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nesting: int = 0
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assert self.text is not None
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tokgen = generate_tokens(self.text)
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for toktype, ttext, (slineno, _), (elineno, _), ltext in tokgen:
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if self.show_tokens: # pragma: debugging
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print(
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'%10s %5s %-20r %r' % (
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tokenize.tok_name.get(toktype, toktype),
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nice_pair((slineno, elineno)), ttext, ltext,
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),
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)
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if toktype == token.INDENT:
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indent += 1
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elif toktype == token.DEDENT:
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indent -= 1
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elif toktype == token.NAME:
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if ttext == 'class':
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# Class definitions look like branches in the bytecode, so
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# we need to exclude them. The simplest way is to note the
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# lines with the "class" keyword.
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self.raw_classdefs.add(slineno)
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elif toktype == token.OP:
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if ttext == ':' and nesting == 0:
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should_exclude = (
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self.raw_excluded.intersection(range(first_line, elineno + 1)) or
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excluding_decorators
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)
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if not excluding and should_exclude:
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# Start excluding a suite. We trigger off of the colon
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# token so that the #pragma comment will be recognized on
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# the same line as the colon.
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self.raw_excluded.add(elineno)
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exclude_indent = indent
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excluding = True
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excluding_decorators = False
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elif ttext == '@' and first_on_line:
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# A decorator.
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if elineno in self.raw_excluded:
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excluding_decorators = True
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if excluding_decorators:
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self.raw_excluded.add(elineno)
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elif ttext in '([{':
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nesting += 1
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elif ttext in ')]}':
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nesting -= 1
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elif toktype == token.STRING:
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if prev_toktype == token.INDENT:
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# Strings that are first on an indented line are docstrings.
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# (a trick from trace.py in the stdlib.) This works for
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# 99.9999% of cases.
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self.raw_docstrings.update(range(slineno, elineno + 1))
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elif toktype == token.NEWLINE:
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if first_line and elineno != first_line:
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# We're at the end of a line, and we've ended on a
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# different line than the first line of the statement,
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# so record a multi-line range.
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for l in range(first_line, elineno + 1):
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self._multiline[l] = first_line
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first_line = 0
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first_on_line = True
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if ttext.strip() and toktype != tokenize.COMMENT:
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# A non-white-space token.
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empty = False
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if not first_line:
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# The token is not white space, and is the first in a statement.
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first_line = slineno
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# Check whether to end an excluded suite.
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if excluding and indent <= exclude_indent:
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excluding = False
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if excluding:
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self.raw_excluded.add(elineno)
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first_on_line = False
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prev_toktype = toktype
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# Find the starts of the executable statements.
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if not empty:
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byte_parser = ByteParser(self.text, filename=self.filename)
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self.raw_statements.update(byte_parser._find_statements())
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# The first line of modules can lie and say 1 always, even if the first
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# line of code is later. If so, map 1 to the actual first line of the
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# module.
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if env.PYBEHAVIOR.module_firstline_1 and self._multiline:
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self._multiline[1] = min(self.raw_statements)
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def first_line(self, lineno: TLineNo) -> TLineNo:
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"""Return the first line number of the statement including `lineno`."""
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if lineno < 0:
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lineno = -self._multiline.get(-lineno, -lineno)
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else:
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lineno = self._multiline.get(lineno, lineno)
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return lineno
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def first_lines(self, linenos: Iterable[TLineNo]) -> set[TLineNo]:
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"""Map the line numbers in `linenos` to the correct first line of the
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statement.
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Returns a set of the first lines.
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"""
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return {self.first_line(l) for l in linenos}
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def translate_lines(self, lines: Iterable[TLineNo]) -> set[TLineNo]:
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"""Implement `FileReporter.translate_lines`."""
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return self.first_lines(lines)
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def translate_arcs(self, arcs: Iterable[TArc]) -> set[TArc]:
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"""Implement `FileReporter.translate_arcs`."""
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return {(self.first_line(a), self.first_line(b)) for (a, b) in arcs}
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def parse_source(self) -> None:
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"""Parse source text to find executable lines, excluded lines, etc.
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Sets the .excluded and .statements attributes, normalized to the first
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line of multi-line statements.
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"""
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try:
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self._raw_parse()
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except (tokenize.TokenError, IndentationError, SyntaxError) as err:
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if hasattr(err, 'lineno'):
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lineno = err.lineno # IndentationError
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else:
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lineno = err.args[1][0] # TokenError
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raise NotPython(
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f"Couldn't parse '{self.filename}' as Python source: " +
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f'{err.args[0]!r} at line {lineno}',
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) from err
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self.excluded = self.first_lines(self.raw_excluded)
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ignore = self.excluded | self.raw_docstrings
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starts = self.raw_statements - ignore
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self.statements = self.first_lines(starts) - ignore
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def arcs(self) -> set[TArc]:
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"""Get information about the arcs available in the code.
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Returns a set of line number pairs. Line numbers have been normalized
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to the first line of multi-line statements.
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"""
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if self._all_arcs is None:
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self._analyze_ast()
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assert self._all_arcs is not None
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return self._all_arcs
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def _analyze_ast(self) -> None:
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"""Run the AstArcAnalyzer and save its results.
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`_all_arcs` is the set of arcs in the code.
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"""
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aaa = AstArcAnalyzer(self.text, self.raw_statements, self._multiline)
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aaa.analyze()
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self._all_arcs = set()
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for l1, l2 in aaa.arcs:
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fl1 = self.first_line(l1)
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fl2 = self.first_line(l2)
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if fl1 != fl2:
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self._all_arcs.add((fl1, fl2))
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self._missing_arc_fragments = aaa.missing_arc_fragments
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def exit_counts(self) -> dict[TLineNo, int]:
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"""Get a count of exits from that each line.
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Excluded lines are excluded.
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"""
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exit_counts: dict[TLineNo, int] = collections.defaultdict(int)
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for l1, l2 in self.arcs():
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if l1 < 0:
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# Don't ever report -1 as a line number
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continue
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if l1 in self.excluded:
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# Don't report excluded lines as line numbers.
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continue
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if l2 in self.excluded:
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# Arcs to excluded lines shouldn't count.
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continue
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exit_counts[l1] += 1
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# Class definitions have one extra exit, so remove one for each:
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for l in self.raw_classdefs:
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# Ensure key is there: class definitions can include excluded lines.
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if l in exit_counts:
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exit_counts[l] -= 1
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return exit_counts
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def missing_arc_description(
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self,
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start: TLineNo,
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end: TLineNo,
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executed_arcs: Iterable[TArc] | None = None,
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) -> str:
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"""Provide an English sentence describing a missing arc."""
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if self._missing_arc_fragments is None:
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self._analyze_ast()
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assert self._missing_arc_fragments is not None
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actual_start = start
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if (
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executed_arcs and
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end < 0 and end == -start and
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(end, start) not in executed_arcs and
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(end, start) in self._missing_arc_fragments
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):
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# It's a one-line callable, and we never even started it,
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# and we have a message about not starting it.
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start, end = end, start
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fragment_pairs = self._missing_arc_fragments.get((start, end), [(None, None)])
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msgs = []
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for smsg, emsg in fragment_pairs:
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if emsg is None:
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if end < 0:
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# Hmm, maybe we have a one-line callable, let's check.
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if (-end, end) in self._missing_arc_fragments:
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return self.missing_arc_description(-end, end)
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emsg = "didn't jump to the function exit"
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else:
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emsg = "didn't jump to line {lineno}"
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emsg = emsg.format(lineno=end)
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msg = f'line {actual_start} {emsg}'
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if smsg is not None:
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msg += f', because {smsg.format(lineno=actual_start)}'
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msgs.append(msg)
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return ' or '.join(msgs)
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class ByteParser:
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"""Parse bytecode to understand the structure of code."""
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def __init__(
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self,
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text: str,
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code: CodeType | None = None,
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filename: str | None = None,
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) -> None:
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self.text = text
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if code is not None:
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self.code = code
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else:
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assert filename is not None
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try:
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self.code = compile(text, filename, 'exec', dont_inherit=True)
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except SyntaxError as synerr:
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raise NotPython(
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"Couldn't parse '%s' as Python source: '%s' at line %d" % (
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filename, synerr.msg, synerr.lineno or 0,
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),
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) from synerr
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def child_parsers(self) -> Iterable[ByteParser]:
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"""Iterate over all the code objects nested within this one.
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The iteration includes `self` as its first value.
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"""
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return (ByteParser(self.text, code=c) for c in code_objects(self.code))
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def _line_numbers(self) -> Iterable[TLineNo]:
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"""Yield the line numbers possible in this code object.
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Uses co_lnotab described in Python/compile.c to find the
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line numbers. Produces a sequence: l0, l1, ...
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"""
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if hasattr(self.code, 'co_lines'):
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# PYVERSIONS: new in 3.10
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for _, _, line in self.code.co_lines():
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if line:
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yield line
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else:
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# Adapted from dis.py in the standard library.
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byte_increments = self.code.co_lnotab[0::2]
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line_increments = self.code.co_lnotab[1::2]
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last_line_num = None
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line_num = self.code.co_firstlineno
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byte_num = 0
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for byte_incr, line_incr in zip(byte_increments, line_increments):
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if byte_incr:
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if line_num != last_line_num:
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yield line_num
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last_line_num = line_num
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byte_num += byte_incr
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if line_incr >= 0x80:
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line_incr -= 0x100
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line_num += line_incr
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if line_num != last_line_num:
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yield line_num
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def _find_statements(self) -> Iterable[TLineNo]:
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"""Find the statements in `self.code`.
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Produce a sequence of line numbers that start statements. Recurses
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into all code objects reachable from `self.code`.
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"""
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for bp in self.child_parsers():
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# Get all of the lineno information from this code.
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yield from bp._line_numbers()
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|
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#
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# AST analysis
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#
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@dataclass(frozen=True, order=True)
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class ArcStart:
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"""The information needed to start an arc.
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`lineno` is the line number the arc starts from.
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`cause` is an English text fragment used as the `startmsg` for
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AstArcAnalyzer.missing_arc_fragments. It will be used to describe why an
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arc wasn't executed, so should fit well into a sentence of the form,
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"Line 17 didn't run because {cause}." The fragment can include "{lineno}"
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to have `lineno` interpolated into it.
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"""
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lineno: TLineNo
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cause: str = ''
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class TAddArcFn(Protocol):
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"""The type for AstArcAnalyzer.add_arc()."""
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def __call__(
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self,
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start: TLineNo,
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end: TLineNo,
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smsg: str | None = None,
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emsg: str | None = None,
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) -> None:
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...
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TArcFragments = Dict[TArc, List[Tuple[Optional[str], Optional[str]]]]
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class Block:
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"""
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Blocks need to handle various exiting statements in their own ways.
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All of these methods take a list of exits, and a callable `add_arc`
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function that they can use to add arcs if needed. They return True if the
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exits are handled, or False if the search should continue up the block
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stack.
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"""
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# pylint: disable=unused-argument
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def process_break_exits(self, exits: set[ArcStart], add_arc: TAddArcFn) -> bool:
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"""Process break exits."""
|
|
# Because break can only appear in loops, and most subclasses
|
|
# implement process_break_exits, this function is never reached.
|
|
raise AssertionError
|
|
|
|
def process_continue_exits(self, exits: set[ArcStart], add_arc: TAddArcFn) -> bool:
|
|
"""Process continue exits."""
|
|
# Because continue can only appear in loops, and most subclasses
|
|
# implement process_continue_exits, this function is never reached.
|
|
raise AssertionError
|
|
|
|
def process_raise_exits(self, exits: set[ArcStart], add_arc: TAddArcFn) -> bool:
|
|
"""Process raise exits."""
|
|
return False
|
|
|
|
def process_return_exits(self, exits: set[ArcStart], add_arc: TAddArcFn) -> bool:
|
|
"""Process return exits."""
|
|
return False
|
|
|
|
|
|
class LoopBlock(Block):
|
|
"""A block on the block stack representing a `for` or `while` loop."""
|
|
|
|
def __init__(self, start: TLineNo) -> None:
|
|
# The line number where the loop starts.
|
|
self.start = start
|
|
# A set of ArcStarts, the arcs from break statements exiting this loop.
|
|
self.break_exits: set[ArcStart] = set()
|
|
|
|
def process_break_exits(self, exits: set[ArcStart], add_arc: TAddArcFn) -> bool:
|
|
self.break_exits.update(exits)
|
|
return True
|
|
|
|
def process_continue_exits(self, exits: set[ArcStart], add_arc: TAddArcFn) -> bool:
|
|
for xit in exits:
|
|
add_arc(xit.lineno, self.start, xit.cause)
|
|
return True
|
|
|
|
|
|
class FunctionBlock(Block):
|
|
"""A block on the block stack representing a function definition."""
|
|
|
|
def __init__(self, start: TLineNo, name: str) -> None:
|
|
# The line number where the function starts.
|
|
self.start = start
|
|
# The name of the function.
|
|
self.name = name
|
|
|
|
def process_raise_exits(self, exits: set[ArcStart], add_arc: TAddArcFn) -> bool:
|
|
for xit in exits:
|
|
add_arc(
|
|
xit.lineno, -self.start, xit.cause,
|
|
f"didn't except from function {self.name!r}",
|
|
)
|
|
return True
|
|
|
|
def process_return_exits(self, exits: set[ArcStart], add_arc: TAddArcFn) -> bool:
|
|
for xit in exits:
|
|
add_arc(
|
|
xit.lineno, -self.start, xit.cause,
|
|
f"didn't return from function {self.name!r}",
|
|
)
|
|
return True
|
|
|
|
|
|
class TryBlock(Block):
|
|
"""A block on the block stack representing a `try` block."""
|
|
|
|
def __init__(self, handler_start: TLineNo | None, final_start: TLineNo | None) -> None:
|
|
# The line number of the first "except" handler, if any.
|
|
self.handler_start = handler_start
|
|
# The line number of the "finally:" clause, if any.
|
|
self.final_start = final_start
|
|
|
|
# The ArcStarts for breaks/continues/returns/raises inside the "try:"
|
|
# that need to route through the "finally:" clause.
|
|
self.break_from: set[ArcStart] = set()
|
|
self.continue_from: set[ArcStart] = set()
|
|
self.raise_from: set[ArcStart] = set()
|
|
self.return_from: set[ArcStart] = set()
|
|
|
|
def process_break_exits(self, exits: set[ArcStart], add_arc: TAddArcFn) -> bool:
|
|
if self.final_start is not None:
|
|
self.break_from.update(exits)
|
|
return True
|
|
return False
|
|
|
|
def process_continue_exits(self, exits: set[ArcStart], add_arc: TAddArcFn) -> bool:
|
|
if self.final_start is not None:
|
|
self.continue_from.update(exits)
|
|
return True
|
|
return False
|
|
|
|
def process_raise_exits(self, exits: set[ArcStart], add_arc: TAddArcFn) -> bool:
|
|
if self.handler_start is not None:
|
|
for xit in exits:
|
|
add_arc(xit.lineno, self.handler_start, xit.cause)
|
|
else:
|
|
assert self.final_start is not None
|
|
self.raise_from.update(exits)
|
|
return True
|
|
|
|
def process_return_exits(self, exits: set[ArcStart], add_arc: TAddArcFn) -> bool:
|
|
if self.final_start is not None:
|
|
self.return_from.update(exits)
|
|
return True
|
|
return False
|
|
|
|
|
|
class WithBlock(Block):
|
|
"""A block on the block stack representing a `with` block."""
|
|
|
|
def __init__(self, start: TLineNo) -> None:
|
|
# We only ever use this block if it is needed, so that we don't have to
|
|
# check this setting in all the methods.
|
|
assert env.PYBEHAVIOR.exit_through_with
|
|
|
|
# The line number of the with statement.
|
|
self.start = start
|
|
|
|
# The ArcStarts for breaks/continues/returns/raises inside the "with:"
|
|
# that need to go through the with-statement while exiting.
|
|
self.break_from: set[ArcStart] = set()
|
|
self.continue_from: set[ArcStart] = set()
|
|
self.return_from: set[ArcStart] = set()
|
|
|
|
def _process_exits(
|
|
self,
|
|
exits: set[ArcStart],
|
|
add_arc: TAddArcFn,
|
|
from_set: set[ArcStart] | None = None,
|
|
) -> bool:
|
|
"""Helper to process the four kinds of exits."""
|
|
for xit in exits:
|
|
add_arc(xit.lineno, self.start, xit.cause)
|
|
if from_set is not None:
|
|
from_set.update(exits)
|
|
return True
|
|
|
|
def process_break_exits(self, exits: set[ArcStart], add_arc: TAddArcFn) -> bool:
|
|
return self._process_exits(exits, add_arc, self.break_from)
|
|
|
|
def process_continue_exits(self, exits: set[ArcStart], add_arc: TAddArcFn) -> bool:
|
|
return self._process_exits(exits, add_arc, self.continue_from)
|
|
|
|
def process_raise_exits(self, exits: set[ArcStart], add_arc: TAddArcFn) -> bool:
|
|
return self._process_exits(exits, add_arc)
|
|
|
|
def process_return_exits(self, exits: set[ArcStart], add_arc: TAddArcFn) -> bool:
|
|
return self._process_exits(exits, add_arc, self.return_from)
|
|
|
|
|
|
class NodeList(ast.AST):
|
|
"""A synthetic fictitious node, containing a sequence of nodes.
|
|
|
|
This is used when collapsing optimized if-statements, to represent the
|
|
unconditional execution of one of the clauses.
|
|
|
|
"""
|
|
|
|
def __init__(self, body: Sequence[ast.AST]) -> None:
|
|
self.body = body
|
|
self.lineno = body[0].lineno
|
|
|
|
# TODO: some add_arcs methods here don't add arcs, they return them. Rename them.
|
|
# TODO: the cause messages have too many commas.
|
|
# TODO: Shouldn't the cause messages join with "and" instead of "or"?
|
|
|
|
|
|
def _make_expression_code_method(noun: str) -> Callable[[AstArcAnalyzer, ast.AST], None]:
|
|
"""A function to make methods for expression-based callable _code_object__ methods."""
|
|
|
|
def _code_object__expression_callable(self: AstArcAnalyzer, node: ast.AST) -> None:
|
|
start = self.line_for_node(node)
|
|
self.add_arc(-start, start, None, f"didn't run the {noun} on line {start}")
|
|
self.add_arc(start, -start, None, f"didn't finish the {noun} on line {start}")
|
|
return _code_object__expression_callable
|
|
|
|
|
|
class AstArcAnalyzer:
|
|
"""Analyze source text with an AST to find executable code paths."""
|
|
|
|
def __init__(
|
|
self,
|
|
text: str,
|
|
statements: set[TLineNo],
|
|
multiline: dict[TLineNo, TLineNo],
|
|
) -> None:
|
|
self.root_node = ast.parse(text)
|
|
# TODO: I think this is happening in too many places.
|
|
self.statements = {multiline.get(l, l) for l in statements}
|
|
self.multiline = multiline
|
|
|
|
# Turn on AST dumps with an environment variable.
|
|
# $set_env.py: COVERAGE_AST_DUMP - Dump the AST nodes when parsing code.
|
|
dump_ast = bool(int(os.getenv('COVERAGE_AST_DUMP', '0')))
|
|
|
|
if dump_ast: # pragma: debugging
|
|
# Dump the AST so that failing tests have helpful output.
|
|
print(f'Statements: {self.statements}')
|
|
print(f'Multiline map: {self.multiline}')
|
|
dumpkw: dict[str, Any] = {}
|
|
if sys.version_info >= (3, 9):
|
|
dumpkw['indent'] = 4
|
|
print(ast.dump(self.root_node, include_attributes=True, **dumpkw))
|
|
|
|
self.arcs: set[TArc] = set()
|
|
|
|
# A map from arc pairs to a list of pairs of sentence fragments:
|
|
# { (start, end): [(startmsg, endmsg), ...], }
|
|
#
|
|
# For an arc from line 17, they should be usable like:
|
|
# "Line 17 {endmsg}, because {startmsg}"
|
|
self.missing_arc_fragments: TArcFragments = collections.defaultdict(list)
|
|
self.block_stack: list[Block] = []
|
|
|
|
# $set_env.py: COVERAGE_TRACK_ARCS - Trace possible arcs added while parsing code.
|
|
self.debug = bool(int(os.getenv('COVERAGE_TRACK_ARCS', '0')))
|
|
|
|
def analyze(self) -> None:
|
|
"""Examine the AST tree from `root_node` to determine possible arcs.
|
|
|
|
This sets the `arcs` attribute to be a set of (from, to) line number
|
|
pairs.
|
|
|
|
"""
|
|
for node in ast.walk(self.root_node):
|
|
node_name = node.__class__.__name__
|
|
code_object_handler = getattr(self, '_code_object__' + node_name, None)
|
|
if code_object_handler is not None:
|
|
code_object_handler(node)
|
|
|
|
def add_arc(
|
|
self,
|
|
start: TLineNo,
|
|
end: TLineNo,
|
|
smsg: str | None = None,
|
|
emsg: str | None = None,
|
|
) -> None:
|
|
"""Add an arc, including message fragments to use if it is missing."""
|
|
if self.debug: # pragma: debugging
|
|
print(f'\nAdding possible arc: ({start}, {end}): {smsg!r}, {emsg!r}')
|
|
print(short_stack())
|
|
self.arcs.add((start, end))
|
|
|
|
if smsg is not None or emsg is not None:
|
|
self.missing_arc_fragments[(start, end)].append((smsg, emsg))
|
|
|
|
def nearest_blocks(self) -> Iterable[Block]:
|
|
"""Yield the blocks in nearest-to-farthest order."""
|
|
return reversed(self.block_stack)
|
|
|
|
def line_for_node(self, node: ast.AST) -> TLineNo:
|
|
"""What is the right line number to use for this node?
|
|
|
|
This dispatches to _line__Node functions where needed.
|
|
|
|
"""
|
|
node_name = node.__class__.__name__
|
|
handler = cast(
|
|
Optional[Callable[[ast.AST], TLineNo]],
|
|
getattr(self, '_line__' + node_name, None),
|
|
)
|
|
if handler is not None:
|
|
return handler(node)
|
|
else:
|
|
return node.lineno
|
|
|
|
def _line_decorated(self, node: ast.FunctionDef) -> TLineNo:
|
|
"""Compute first line number for things that can be decorated (classes and functions)."""
|
|
if node.decorator_list:
|
|
lineno = node.decorator_list[0].lineno
|
|
else:
|
|
lineno = node.lineno
|
|
return lineno
|
|
|
|
def _line__Assign(self, node: ast.Assign) -> TLineNo:
|
|
return self.line_for_node(node.value)
|
|
|
|
_line__ClassDef = _line_decorated
|
|
|
|
def _line__Dict(self, node: ast.Dict) -> TLineNo:
|
|
if node.keys:
|
|
if node.keys[0] is not None:
|
|
return node.keys[0].lineno
|
|
else:
|
|
# Unpacked dict literals `{**{"a":1}}` have None as the key,
|
|
# use the value in that case.
|
|
return node.values[0].lineno
|
|
else:
|
|
return node.lineno
|
|
|
|
_line__FunctionDef = _line_decorated
|
|
_line__AsyncFunctionDef = _line_decorated
|
|
|
|
def _line__List(self, node: ast.List) -> TLineNo:
|
|
if node.elts:
|
|
return self.line_for_node(node.elts[0])
|
|
else:
|
|
return node.lineno
|
|
|
|
def _line__Module(self, node: ast.Module) -> TLineNo:
|
|
if env.PYBEHAVIOR.module_firstline_1:
|
|
return 1
|
|
elif node.body:
|
|
return self.line_for_node(node.body[0])
|
|
else:
|
|
# Empty modules have no line number, they always start at 1.
|
|
return 1
|
|
|
|
# The node types that just flow to the next node with no complications.
|
|
OK_TO_DEFAULT = {
|
|
'AnnAssign', 'Assign', 'Assert', 'AugAssign', 'Delete', 'Expr', 'Global',
|
|
'Import', 'ImportFrom', 'Nonlocal', 'Pass',
|
|
}
|
|
|
|
def add_arcs(self, node: ast.AST) -> set[ArcStart]:
|
|
"""Add the arcs for `node`.
|
|
|
|
Return a set of ArcStarts, exits from this node to the next. Because a
|
|
node represents an entire sub-tree (including its children), the exits
|
|
from a node can be arbitrarily complex::
|
|
|
|
if something(1):
|
|
if other(2):
|
|
doit(3)
|
|
else:
|
|
doit(5)
|
|
|
|
There are two exits from line 1: they start at line 3 and line 5.
|
|
|
|
"""
|
|
node_name = node.__class__.__name__
|
|
handler = cast(
|
|
Optional[Callable[[ast.AST], Set[ArcStart]]],
|
|
getattr(self, '_handle__' + node_name, None),
|
|
)
|
|
if handler is not None:
|
|
return handler(node)
|
|
else:
|
|
# No handler: either it's something that's ok to default (a simple
|
|
# statement), or it's something we overlooked.
|
|
if env.TESTING:
|
|
if node_name not in self.OK_TO_DEFAULT:
|
|
raise RuntimeError(f'*** Unhandled: {node}') # pragma: only failure
|
|
|
|
# Default for simple statements: one exit from this node.
|
|
return {ArcStart(self.line_for_node(node))}
|
|
|
|
def add_body_arcs(
|
|
self,
|
|
body: Sequence[ast.AST],
|
|
from_start: ArcStart | None = None,
|
|
prev_starts: set[ArcStart] | None = None,
|
|
) -> set[ArcStart]:
|
|
"""Add arcs for the body of a compound statement.
|
|
|
|
`body` is the body node. `from_start` is a single `ArcStart` that can
|
|
be the previous line in flow before this body. `prev_starts` is a set
|
|
of ArcStarts that can be the previous line. Only one of them should be
|
|
given.
|
|
|
|
Returns a set of ArcStarts, the exits from this body.
|
|
|
|
"""
|
|
if prev_starts is None:
|
|
assert from_start is not None
|
|
prev_starts = {from_start}
|
|
for body_node in body:
|
|
lineno = self.line_for_node(body_node)
|
|
first_line = self.multiline.get(lineno, lineno)
|
|
if first_line not in self.statements:
|
|
maybe_body_node = self.find_non_missing_node(body_node)
|
|
if maybe_body_node is None:
|
|
continue
|
|
body_node = maybe_body_node
|
|
lineno = self.line_for_node(body_node)
|
|
for prev_start in prev_starts:
|
|
self.add_arc(prev_start.lineno, lineno, prev_start.cause)
|
|
prev_starts = self.add_arcs(body_node)
|
|
return prev_starts
|
|
|
|
def find_non_missing_node(self, node: ast.AST) -> ast.AST | None:
|
|
"""Search `node` looking for a child that has not been optimized away.
|
|
|
|
This might return the node you started with, or it will work recursively
|
|
to find a child node in self.statements.
|
|
|
|
Returns a node, or None if none of the node remains.
|
|
|
|
"""
|
|
# This repeats work just done in add_body_arcs, but this duplication
|
|
# means we can avoid a function call in the 99.9999% case of not
|
|
# optimizing away statements.
|
|
lineno = self.line_for_node(node)
|
|
first_line = self.multiline.get(lineno, lineno)
|
|
if first_line in self.statements:
|
|
return node
|
|
|
|
missing_fn = cast(
|
|
Optional[Callable[[ast.AST], Optional[ast.AST]]],
|
|
getattr(self, '_missing__' + node.__class__.__name__, None),
|
|
)
|
|
if missing_fn is not None:
|
|
ret_node = missing_fn(node)
|
|
else:
|
|
ret_node = None
|
|
return ret_node
|
|
|
|
# Missing nodes: _missing__*
|
|
#
|
|
# Entire statements can be optimized away by Python. They will appear in
|
|
# the AST, but not the bytecode. These functions are called (by
|
|
# find_non_missing_node) to find a node to use instead of the missing
|
|
# node. They can return None if the node should truly be gone.
|
|
|
|
def _missing__If(self, node: ast.If) -> ast.AST | None:
|
|
# If the if-node is missing, then one of its children might still be
|
|
# here, but not both. So return the first of the two that isn't missing.
|
|
# Use a NodeList to hold the clauses as a single node.
|
|
non_missing = self.find_non_missing_node(NodeList(node.body))
|
|
if non_missing:
|
|
return non_missing
|
|
if node.orelse:
|
|
return self.find_non_missing_node(NodeList(node.orelse))
|
|
return None
|
|
|
|
def _missing__NodeList(self, node: NodeList) -> ast.AST | None:
|
|
# A NodeList might be a mixture of missing and present nodes. Find the
|
|
# ones that are present.
|
|
non_missing_children = []
|
|
for child in node.body:
|
|
maybe_child = self.find_non_missing_node(child)
|
|
if maybe_child is not None:
|
|
non_missing_children.append(maybe_child)
|
|
|
|
# Return the simplest representation of the present children.
|
|
if not non_missing_children:
|
|
return None
|
|
if len(non_missing_children) == 1:
|
|
return non_missing_children[0]
|
|
return NodeList(non_missing_children)
|
|
|
|
def _missing__While(self, node: ast.While) -> ast.AST | None:
|
|
body_nodes = self.find_non_missing_node(NodeList(node.body))
|
|
if not body_nodes:
|
|
return None
|
|
# Make a synthetic While-true node.
|
|
new_while = ast.While()
|
|
new_while.lineno = body_nodes.lineno
|
|
new_while.test = ast.Name()
|
|
new_while.test.lineno = body_nodes.lineno
|
|
new_while.test.id = 'True'
|
|
assert hasattr(body_nodes, 'body')
|
|
new_while.body = body_nodes.body
|
|
new_while.orelse = []
|
|
return new_while
|
|
|
|
def is_constant_expr(self, node: ast.AST) -> str | None:
|
|
"""Is this a compile-time constant?"""
|
|
node_name = node.__class__.__name__
|
|
if node_name in ['Constant', 'NameConstant', 'Num']:
|
|
return 'Num'
|
|
elif isinstance(node, ast.Name):
|
|
if node.id in ['True', 'False', 'None', '__debug__']:
|
|
return 'Name'
|
|
return None
|
|
|
|
# In the fullness of time, these might be good tests to write:
|
|
# while EXPR:
|
|
# while False:
|
|
# listcomps hidden deep in other expressions
|
|
# listcomps hidden in lists: x = [[i for i in range(10)]]
|
|
# nested function definitions
|
|
|
|
# Exit processing: process_*_exits
|
|
#
|
|
# These functions process the four kinds of jump exits: break, continue,
|
|
# raise, and return. To figure out where an exit goes, we have to look at
|
|
# the block stack context. For example, a break will jump to the nearest
|
|
# enclosing loop block, or the nearest enclosing finally block, whichever
|
|
# is nearer.
|
|
|
|
def process_break_exits(self, exits: set[ArcStart]) -> None:
|
|
"""Add arcs due to jumps from `exits` being breaks."""
|
|
for block in self.nearest_blocks(): # pragma: always breaks
|
|
if block.process_break_exits(exits, self.add_arc):
|
|
break
|
|
|
|
def process_continue_exits(self, exits: set[ArcStart]) -> None:
|
|
"""Add arcs due to jumps from `exits` being continues."""
|
|
for block in self.nearest_blocks(): # pragma: always breaks
|
|
if block.process_continue_exits(exits, self.add_arc):
|
|
break
|
|
|
|
def process_raise_exits(self, exits: set[ArcStart]) -> None:
|
|
"""Add arcs due to jumps from `exits` being raises."""
|
|
for block in self.nearest_blocks():
|
|
if block.process_raise_exits(exits, self.add_arc):
|
|
break
|
|
|
|
def process_return_exits(self, exits: set[ArcStart]) -> None:
|
|
"""Add arcs due to jumps from `exits` being returns."""
|
|
for block in self.nearest_blocks(): # pragma: always breaks
|
|
if block.process_return_exits(exits, self.add_arc):
|
|
break
|
|
|
|
# Handlers: _handle__*
|
|
#
|
|
# Each handler deals with a specific AST node type, dispatched from
|
|
# add_arcs. Handlers return the set of exits from that node, and can
|
|
# also call self.add_arc to record arcs they find. These functions mirror
|
|
# the Python semantics of each syntactic construct. See the docstring
|
|
# for add_arcs to understand the concept of exits from a node.
|
|
#
|
|
# Every node type that represents a statement should have a handler, or it
|
|
# should be listed in OK_TO_DEFAULT.
|
|
|
|
def _handle__Break(self, node: ast.Break) -> set[ArcStart]:
|
|
here = self.line_for_node(node)
|
|
break_start = ArcStart(here, cause="the break on line {lineno} wasn't executed")
|
|
self.process_break_exits({break_start})
|
|
return set()
|
|
|
|
def _handle_decorated(self, node: ast.FunctionDef) -> set[ArcStart]:
|
|
"""Add arcs for things that can be decorated (classes and functions)."""
|
|
main_line: TLineNo = node.lineno
|
|
last: TLineNo | None = node.lineno
|
|
decs = node.decorator_list
|
|
if decs:
|
|
last = None
|
|
for dec_node in decs:
|
|
dec_start = self.line_for_node(dec_node)
|
|
if last is not None and dec_start != last: # type: ignore[unreachable]
|
|
self.add_arc(last, dec_start) # type: ignore[unreachable]
|
|
last = dec_start
|
|
assert last is not None
|
|
self.add_arc(last, main_line)
|
|
last = main_line
|
|
if env.PYBEHAVIOR.trace_decorator_line_again:
|
|
for top, bot in zip(decs, decs[1:]):
|
|
self.add_arc(self.line_for_node(bot), self.line_for_node(top))
|
|
self.add_arc(self.line_for_node(decs[0]), main_line)
|
|
self.add_arc(main_line, self.line_for_node(decs[-1]))
|
|
# The definition line may have been missed, but we should have it
|
|
# in `self.statements`. For some constructs, `line_for_node` is
|
|
# not what we'd think of as the first line in the statement, so map
|
|
# it to the first one.
|
|
if node.body:
|
|
body_start = self.line_for_node(node.body[0])
|
|
body_start = self.multiline.get(body_start, body_start)
|
|
# The body is handled in collect_arcs.
|
|
assert last is not None
|
|
return {ArcStart(last)}
|
|
|
|
_handle__ClassDef = _handle_decorated
|
|
|
|
def _handle__Continue(self, node: ast.Continue) -> set[ArcStart]:
|
|
here = self.line_for_node(node)
|
|
continue_start = ArcStart(here, cause="the continue on line {lineno} wasn't executed")
|
|
self.process_continue_exits({continue_start})
|
|
return set()
|
|
|
|
def _handle__For(self, node: ast.For) -> set[ArcStart]:
|
|
start = self.line_for_node(node.iter)
|
|
self.block_stack.append(LoopBlock(start=start))
|
|
from_start = ArcStart(start, cause='the loop on line {lineno} never started')
|
|
exits = self.add_body_arcs(node.body, from_start=from_start)
|
|
# Any exit from the body will go back to the top of the loop.
|
|
for xit in exits:
|
|
self.add_arc(xit.lineno, start, xit.cause)
|
|
my_block = self.block_stack.pop()
|
|
assert isinstance(my_block, LoopBlock)
|
|
exits = my_block.break_exits
|
|
from_start = ArcStart(start, cause="the loop on line {lineno} didn't complete")
|
|
if node.orelse:
|
|
else_exits = self.add_body_arcs(node.orelse, from_start=from_start)
|
|
exits |= else_exits
|
|
else:
|
|
# No else clause: exit from the for line.
|
|
exits.add(from_start)
|
|
return exits
|
|
|
|
_handle__AsyncFor = _handle__For
|
|
|
|
_handle__FunctionDef = _handle_decorated
|
|
_handle__AsyncFunctionDef = _handle_decorated
|
|
|
|
def _handle__If(self, node: ast.If) -> set[ArcStart]:
|
|
start = self.line_for_node(node.test)
|
|
from_start = ArcStart(start, cause='the condition on line {lineno} was never true')
|
|
exits = self.add_body_arcs(node.body, from_start=from_start)
|
|
from_start = ArcStart(start, cause='the condition on line {lineno} was never false')
|
|
exits |= self.add_body_arcs(node.orelse, from_start=from_start)
|
|
return exits
|
|
|
|
if sys.version_info >= (3, 10):
|
|
def _handle__Match(self, node: ast.Match) -> set[ArcStart]:
|
|
start = self.line_for_node(node)
|
|
last_start = start
|
|
exits = set()
|
|
had_wildcard = False
|
|
for case in node.cases:
|
|
case_start = self.line_for_node(case.pattern)
|
|
pattern = case.pattern
|
|
while isinstance(pattern, ast.MatchOr):
|
|
pattern = pattern.patterns[-1]
|
|
if isinstance(pattern, ast.MatchAs):
|
|
had_wildcard = True
|
|
self.add_arc(last_start, case_start, 'the pattern on line {lineno} always matched')
|
|
from_start = ArcStart(
|
|
case_start,
|
|
cause='the pattern on line {lineno} never matched',
|
|
)
|
|
exits |= self.add_body_arcs(case.body, from_start=from_start)
|
|
last_start = case_start
|
|
if not had_wildcard:
|
|
exits.add(
|
|
ArcStart(case_start, cause='the pattern on line {lineno} always matched'),
|
|
)
|
|
return exits
|
|
|
|
def _handle__NodeList(self, node: NodeList) -> set[ArcStart]:
|
|
start = self.line_for_node(node)
|
|
exits = self.add_body_arcs(node.body, from_start=ArcStart(start))
|
|
return exits
|
|
|
|
def _handle__Raise(self, node: ast.Raise) -> set[ArcStart]:
|
|
here = self.line_for_node(node)
|
|
raise_start = ArcStart(here, cause="the raise on line {lineno} wasn't executed")
|
|
self.process_raise_exits({raise_start})
|
|
# `raise` statement jumps away, no exits from here.
|
|
return set()
|
|
|
|
def _handle__Return(self, node: ast.Return) -> set[ArcStart]:
|
|
here = self.line_for_node(node)
|
|
return_start = ArcStart(here, cause="the return on line {lineno} wasn't executed")
|
|
self.process_return_exits({return_start})
|
|
# `return` statement jumps away, no exits from here.
|
|
return set()
|
|
|
|
def _handle__Try(self, node: ast.Try) -> set[ArcStart]:
|
|
if node.handlers:
|
|
handler_start = self.line_for_node(node.handlers[0])
|
|
else:
|
|
handler_start = None
|
|
|
|
if node.finalbody:
|
|
final_start = self.line_for_node(node.finalbody[0])
|
|
else:
|
|
final_start = None
|
|
|
|
# This is true by virtue of Python syntax: have to have either except
|
|
# or finally, or both.
|
|
assert handler_start is not None or final_start is not None
|
|
try_block = TryBlock(handler_start, final_start)
|
|
self.block_stack.append(try_block)
|
|
|
|
start = self.line_for_node(node)
|
|
exits = self.add_body_arcs(node.body, from_start=ArcStart(start))
|
|
|
|
# We're done with the `try` body, so this block no longer handles
|
|
# exceptions. We keep the block so the `finally` clause can pick up
|
|
# flows from the handlers and `else` clause.
|
|
if node.finalbody:
|
|
try_block.handler_start = None
|
|
if node.handlers:
|
|
# If there are `except` clauses, then raises in the try body
|
|
# will already jump to them. Start this set over for raises in
|
|
# `except` and `else`.
|
|
try_block.raise_from = set()
|
|
else:
|
|
self.block_stack.pop()
|
|
|
|
handler_exits: set[ArcStart] = set()
|
|
|
|
if node.handlers:
|
|
last_handler_start: TLineNo | None = None
|
|
for handler_node in node.handlers:
|
|
handler_start = self.line_for_node(handler_node)
|
|
if last_handler_start is not None:
|
|
self.add_arc(last_handler_start, handler_start)
|
|
last_handler_start = handler_start
|
|
from_cause = "the exception caught by line {lineno} didn't happen"
|
|
from_start = ArcStart(handler_start, cause=from_cause)
|
|
handler_exits |= self.add_body_arcs(handler_node.body, from_start=from_start)
|
|
|
|
if node.orelse:
|
|
exits = self.add_body_arcs(node.orelse, prev_starts=exits)
|
|
|
|
exits |= handler_exits
|
|
|
|
if node.finalbody:
|
|
self.block_stack.pop()
|
|
final_from = ( # You can get to the `finally` clause from:
|
|
exits | # the exits of the body or `else` clause,
|
|
try_block.break_from | # or a `break`,
|
|
try_block.continue_from | # or a `continue`,
|
|
try_block.raise_from | # or a `raise`,
|
|
try_block.return_from # or a `return`.
|
|
)
|
|
|
|
final_exits = self.add_body_arcs(node.finalbody, prev_starts=final_from)
|
|
|
|
if try_block.break_from:
|
|
if env.PYBEHAVIOR.finally_jumps_back:
|
|
for break_line in try_block.break_from:
|
|
lineno = break_line.lineno
|
|
cause = break_line.cause.format(lineno=lineno)
|
|
for final_exit in final_exits:
|
|
self.add_arc(final_exit.lineno, lineno, cause)
|
|
breaks = try_block.break_from
|
|
else:
|
|
breaks = self._combine_finally_starts(try_block.break_from, final_exits)
|
|
self.process_break_exits(breaks)
|
|
|
|
if try_block.continue_from:
|
|
if env.PYBEHAVIOR.finally_jumps_back:
|
|
for continue_line in try_block.continue_from:
|
|
lineno = continue_line.lineno
|
|
cause = continue_line.cause.format(lineno=lineno)
|
|
for final_exit in final_exits:
|
|
self.add_arc(final_exit.lineno, lineno, cause)
|
|
continues = try_block.continue_from
|
|
else:
|
|
continues = self._combine_finally_starts(try_block.continue_from, final_exits)
|
|
self.process_continue_exits(continues)
|
|
|
|
if try_block.raise_from:
|
|
self.process_raise_exits(
|
|
self._combine_finally_starts(try_block.raise_from, final_exits),
|
|
)
|
|
|
|
if try_block.return_from:
|
|
if env.PYBEHAVIOR.finally_jumps_back:
|
|
for return_line in try_block.return_from:
|
|
lineno = return_line.lineno
|
|
cause = return_line.cause.format(lineno=lineno)
|
|
for final_exit in final_exits:
|
|
self.add_arc(final_exit.lineno, lineno, cause)
|
|
returns = try_block.return_from
|
|
else:
|
|
returns = self._combine_finally_starts(try_block.return_from, final_exits)
|
|
self.process_return_exits(returns)
|
|
|
|
if exits:
|
|
# The finally clause's exits are only exits for the try block
|
|
# as a whole if the try block had some exits to begin with.
|
|
exits = final_exits
|
|
|
|
return exits
|
|
|
|
def _combine_finally_starts(self, starts: set[ArcStart], exits: set[ArcStart]) -> set[ArcStart]:
|
|
"""Helper for building the cause of `finally` branches.
|
|
|
|
"finally" clauses might not execute their exits, and the causes could
|
|
be due to a failure to execute any of the exits in the try block. So
|
|
we use the causes from `starts` as the causes for `exits`.
|
|
"""
|
|
causes = []
|
|
for start in sorted(starts):
|
|
if start.cause:
|
|
causes.append(start.cause.format(lineno=start.lineno))
|
|
cause = ' or '.join(causes)
|
|
exits = {ArcStart(xit.lineno, cause) for xit in exits}
|
|
return exits
|
|
|
|
def _handle__While(self, node: ast.While) -> set[ArcStart]:
|
|
start = to_top = self.line_for_node(node.test)
|
|
constant_test = self.is_constant_expr(node.test)
|
|
top_is_body0 = False
|
|
if constant_test:
|
|
top_is_body0 = True
|
|
if env.PYBEHAVIOR.keep_constant_test:
|
|
top_is_body0 = False
|
|
if top_is_body0:
|
|
to_top = self.line_for_node(node.body[0])
|
|
self.block_stack.append(LoopBlock(start=to_top))
|
|
from_start = ArcStart(start, cause='the condition on line {lineno} was never true')
|
|
exits = self.add_body_arcs(node.body, from_start=from_start)
|
|
for xit in exits:
|
|
self.add_arc(xit.lineno, to_top, xit.cause)
|
|
exits = set()
|
|
my_block = self.block_stack.pop()
|
|
assert isinstance(my_block, LoopBlock)
|
|
exits.update(my_block.break_exits)
|
|
from_start = ArcStart(start, cause='the condition on line {lineno} was never false')
|
|
if node.orelse:
|
|
else_exits = self.add_body_arcs(node.orelse, from_start=from_start)
|
|
exits |= else_exits
|
|
else:
|
|
# No `else` clause: you can exit from the start.
|
|
if not constant_test:
|
|
exits.add(from_start)
|
|
return exits
|
|
|
|
def _handle__With(self, node: ast.With) -> set[ArcStart]:
|
|
start = self.line_for_node(node)
|
|
if env.PYBEHAVIOR.exit_through_with:
|
|
self.block_stack.append(WithBlock(start=start))
|
|
exits = self.add_body_arcs(node.body, from_start=ArcStart(start))
|
|
if env.PYBEHAVIOR.exit_through_with:
|
|
with_block = self.block_stack.pop()
|
|
assert isinstance(with_block, WithBlock)
|
|
with_exit = {ArcStart(start)}
|
|
if exits:
|
|
for xit in exits:
|
|
self.add_arc(xit.lineno, start)
|
|
exits = with_exit
|
|
if with_block.break_from:
|
|
self.process_break_exits(
|
|
self._combine_finally_starts(with_block.break_from, with_exit),
|
|
)
|
|
if with_block.continue_from:
|
|
self.process_continue_exits(
|
|
self._combine_finally_starts(with_block.continue_from, with_exit),
|
|
)
|
|
if with_block.return_from:
|
|
self.process_return_exits(
|
|
self._combine_finally_starts(with_block.return_from, with_exit),
|
|
)
|
|
return exits
|
|
|
|
_handle__AsyncWith = _handle__With
|
|
|
|
# Code object dispatchers: _code_object__*
|
|
#
|
|
# These methods are used by analyze() as the start of the analysis.
|
|
# There is one for each construct with a code object.
|
|
|
|
def _code_object__Module(self, node: ast.Module) -> None:
|
|
start = self.line_for_node(node)
|
|
if node.body:
|
|
exits = self.add_body_arcs(node.body, from_start=ArcStart(-start))
|
|
for xit in exits:
|
|
self.add_arc(xit.lineno, -start, xit.cause, "didn't exit the module")
|
|
else:
|
|
# Empty module.
|
|
self.add_arc(-start, start)
|
|
self.add_arc(start, -start)
|
|
|
|
def _code_object__FunctionDef(self, node: ast.FunctionDef) -> None:
|
|
start = self.line_for_node(node)
|
|
self.block_stack.append(FunctionBlock(start=start, name=node.name))
|
|
exits = self.add_body_arcs(node.body, from_start=ArcStart(-start))
|
|
self.process_return_exits(exits)
|
|
self.block_stack.pop()
|
|
|
|
_code_object__AsyncFunctionDef = _code_object__FunctionDef
|
|
|
|
def _code_object__ClassDef(self, node: ast.ClassDef) -> None:
|
|
start = self.line_for_node(node)
|
|
self.add_arc(-start, start)
|
|
exits = self.add_body_arcs(node.body, from_start=ArcStart(start))
|
|
for xit in exits:
|
|
self.add_arc(
|
|
xit.lineno, -start, xit.cause,
|
|
f"didn't exit the body of class {node.name!r}",
|
|
)
|
|
|
|
_code_object__Lambda = _make_expression_code_method('lambda')
|
|
_code_object__GeneratorExp = _make_expression_code_method('generator expression')
|
|
if env.PYBEHAVIOR.comprehensions_are_functions:
|
|
_code_object__DictComp = _make_expression_code_method('dictionary comprehension')
|
|
_code_object__SetComp = _make_expression_code_method('set comprehension')
|
|
_code_object__ListComp = _make_expression_code_method('list comprehension')
|