Files
openswarm/linter/checks/p_private.py
T

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10 KiB
Python

"""Cross-file/class privacy for the ``p_`` naming convention (Java ``private``).
A name prefixed with ``p_`` (or ``P_`` -- the leading p is case-insensitive, so
UPPER_SNAKE constants like ``P_SECRET`` count too) is private to the scope that
owns it, enforced the way Java enforces ``private``:
* **Module-level** ``p_`` symbols (top-level ``def`` / ``class`` / assignment)
are **file-private** -- usable anywhere in their own file, nowhere else.
* **Class members** (``def p_m``, ``self.p_x = ...``, and class-body fields
``p_x: T``) are **class-private** -- any ``recv.p_x`` is legal only when it
appears lexically inside the owning class (or a class nested within it),
matching Java's type-scoped ``private`` while side-stepping type inference.
Strict: a subclass in another file reaching a base's ``p_`` member is a
violation (Java ``private``, not ``protected``). Nested/inner classes may reach
the enclosing class's members and vice versa (the whole enclosing-class stack is
checked). No exemptions -- tests and ``__init__.py`` re-exports are enforced.
How access is detected (no type inference needed): Python reaches class members
only through attribute access (``self.p_x`` / ``obj.p_x``) and module-level
symbols only by bare name (legal in-file) or ``module.p_x`` / ``from m import
p_x`` across files. So the access *form* selects the scoping rule:
* ``recv.p_x`` (attribute load) -> class rule, else module rule
* ``from m import p_x`` -> module rule (cross-file import = leak)
Two passes: phase 1 records ownership, phase 2 checks references against it.
Scoped to ``backend/`` Python, like checks/classes.py.
"""
from __future__ import annotations
import ast
import re
from pathlib import Path
from . import is_excepted, is_excluded, is_lintignored
RULE = "p-private"
# Inline suppression, mirroring vulture's: `# p-private-ignore` (bare) silences
# any p-private finding on the line; `# p-private-ignore: p_x, p_y` only silences
# when the finding names one of the listed symbols (the noqa-with-codes form).
# The comment goes on the *reference* line (where the error is reported), e.g.
# `legacy.p_state # p-private-ignore: p_state`.
_INLINE_IGNORE_RE = re.compile(r"#\s*p-private-ignore\b(?::\s*(?P<names>.*))?")
# name -> set of relative file paths that define it at module level
ModuleOwners = dict[str, set[str]]
# name -> set of (relative file path, qualified class name) that define it as a member
ClassOwners = dict[str, set[tuple[str, str]]]
def _is_p(name: str) -> bool:
# Case-insensitive on the leading p so UPPER_SNAKE constants (P_SECRET) count
# as private too, not just lowercase p_ functions/vars.
return len(name) > 2 and name[:2] in ("p_", "P_")
# --------------------------------------------------------------------------- #
# Phase 1: ownership collection #
# --------------------------------------------------------------------------- #
def _own(name: str, rel: str, stack: list[str], container: str, mp: ModuleOwners, cp: ClassOwners) -> None:
if container == "class":
cp.setdefault(name, set()).add((rel, stack[-1]))
elif container == "module":
mp.setdefault(name, set()).add(rel)
# container == "function" -> local definition, not externally reachable
def _own_target(t: ast.AST, rel: str, stack: list[str], container: str, mp: ModuleOwners, cp: ClassOwners) -> None:
if isinstance(t, ast.Name) and _is_p(t.id):
_own(t.id, rel, stack, container, mp, cp)
elif isinstance(t, ast.Attribute) and _is_p(t.attr):
# self._x = ... / cls._x = ...: owned by the lexically enclosing class.
if stack:
cp.setdefault(t.attr, set()).add((rel, stack[-1]))
elif isinstance(t, ast.Starred):
_own_target(t.value, rel, stack, container, mp, cp)
elif isinstance(t, (ast.Tuple, ast.List)):
for elt in t.elts:
_own_target(elt, rel, stack, container, mp, cp)
def _collect(node: ast.AST, rel: str, stack: list[str], container: str, mp: ModuleOwners, cp: ClassOwners) -> None:
if isinstance(node, ast.ClassDef):
if _is_p(node.name):
_own(node.name, rel, stack, container, mp, cp)
qual = f"{stack[-1]}.{node.name}" if stack else node.name
for child in node.body:
_collect(child, rel, [*stack, qual], "class", mp, cp)
return
if isinstance(node, (ast.FunctionDef, ast.AsyncFunctionDef)):
if _is_p(node.name):
_own(node.name, rel, stack, container, mp, cp)
for child in node.body:
_collect(child, rel, stack, "function", mp, cp)
return
if isinstance(node, (ast.Assign, ast.AnnAssign)):
targets = node.targets if isinstance(node, ast.Assign) else [node.target]
for t in targets:
_own_target(t, rel, stack, container, mp, cp)
return
# Plain compound statements (if/for/while/with/try/...) keep the container so
# a conditionally-defined member is still attributed to its real scope.
for child in ast.iter_child_nodes(node):
_collect(child, rel, stack, container, mp, cp)
# --------------------------------------------------------------------------- #
# Phase 2: reference checking #
# --------------------------------------------------------------------------- #
def _inline_ignored(lines: tuple[str, ...], lineno: int, name: str) -> bool:
"""True when the reported line carries a matching ``# p-private-ignore``."""
if not (1 <= lineno <= len(lines)):
return False
m = _INLINE_IGNORE_RE.search(lines[lineno - 1])
if not m:
return False
names = m.group("names")
if not names:
return True # bare form silences any p-private finding on the line
wanted = {n.strip() for n in names.replace(",", " ").split() if n.strip()}
return name in wanted
def _emit(
out: list[str], seen: set[tuple[int, int, str]], rel: str, node: ast.AST,
name: str, msg: str, lines: tuple[str, ...],
) -> None:
if _inline_ignored(lines, node.lineno, name):
return
key = (node.lineno, node.col_offset, msg)
if key in seen:
return
seen.add(key)
out.append(f"{rel}:{node.lineno}:{node.col_offset + 1}: error: [{RULE}] {msg}")
def _check_attr(
node: ast.Attribute, rel: str, stack: list[str],
mp: ModuleOwners, cp: ClassOwners, out: list[str], seen: set[tuple[int, int, str]],
lines: tuple[str, ...],
) -> None:
name = node.attr
if name in cp:
if cp[name] & {(rel, q) for q in stack}:
return # lexically inside an owning class -> legal
owners = ", ".join(sorted(f"{q} ({r})" for r, q in cp[name]))
_emit(out, seen, rel, node, name, f"class-private '{name}' accessed outside its class (owner: {owners})", lines)
return
if name in mp:
if rel in mp[name]:
return
owners = ", ".join(sorted(mp[name]))
_emit(out, seen, rel, node, name, f"module-private '{name}' accessed outside its file (defined in {owners})", lines)
def _check_import(
name: str, node: ast.AST, rel: str,
mp: ModuleOwners, out: list[str], seen: set[tuple[int, int, str]],
lines: tuple[str, ...],
) -> None:
if name in mp and rel not in mp[name]:
owners = ", ".join(sorted(mp[name]))
_emit(out, seen, rel, node, name, f"module-private '{name}' imported outside its file (defined in {owners})", lines)
def _check_refs(
node: ast.AST, rel: str, stack: list[str],
mp: ModuleOwners, cp: ClassOwners, out: list[str], seen: set[tuple[int, int, str]],
lines: tuple[str, ...],
) -> None:
if isinstance(node, ast.ClassDef):
qual = f"{stack[-1]}.{node.name}" if stack else node.name
# Decorators/bases are evaluated in the enclosing scope, not inside the class.
for outer in (*node.decorator_list, *node.bases, *node.keywords):
_check_refs(outer, rel, stack, mp, cp, out, seen, lines)
for child in node.body:
_check_refs(child, rel, [*stack, qual], mp, cp, out, seen, lines)
return
if isinstance(node, ast.Attribute) and isinstance(node.ctx, ast.Load) and _is_p(node.attr):
_check_attr(node, rel, stack, mp, cp, out, seen, lines)
elif isinstance(node, ast.ImportFrom):
for alias in node.names:
if alias.name != "*" and _is_p(alias.name):
_check_import(alias.name, node, rel, mp, out, seen, lines)
# A function does not open a new *class* scope, so the class stack is carried
# through unchanged; that's why generic descent (not an early return) is right.
for child in ast.iter_child_nodes(node):
_check_refs(child, rel, stack, mp, cp, out, seen, lines)
# --------------------------------------------------------------------------- #
# Runner #
# --------------------------------------------------------------------------- #
def run_p_private_check(
root: Path,
exceptions: dict[str, list[str]],
excludes: list[str],
ignores: dict[Path, set[str]] | None = None,
) -> list[str]:
"""Flag ``p_`` symbols accessed outside their owning file/class."""
backend = root / "backend"
if not backend.is_dir():
return []
# Parse once; phase 1 must see *every* file (even exempted ones) so ownership
# is known when a non-exempt file reaches into them. The source lines are kept
# so phase 2 can honor inline `# p-private-ignore` comments.
trees: list[tuple[Path, str, ast.AST, tuple[str, ...]]] = []
mp: ModuleOwners = {}
cp: ClassOwners = {}
for pyfile in sorted(backend.rglob("*.py")):
if is_excluded(pyfile, root, excludes):
continue
rel = str(pyfile.relative_to(root))
try:
source = pyfile.read_text()
tree = ast.parse(source, filename=rel)
except (OSError, SyntaxError):
continue
trees.append((pyfile, rel, tree, tuple(source.splitlines())))
for child in ast.iter_child_nodes(tree):
_collect(child, rel, [], "module", mp, cp)
# Phase 2 reports only for files that aren't exempted/lintignored.
errors: list[str] = []
for pyfile, rel, tree, lines in trees:
if is_excepted(rel, RULE, exceptions):
continue
if ignores and is_lintignored(pyfile, root, RULE, ignores):
continue
seen: set[tuple[int, int, str]] = set()
out: list[str] = []
_check_refs(tree, rel, [], mp, cp, out, seen, lines)
errors.extend(out)
return errors