test: restore editor aliases and validate procfs guard control flow

tests/test_editor_photoshop_features_more4.py

@@ -93,7 +93,7 @@ def test_custom_filter_reuses_convolve_kernel():
     assert "convolve(readSource(snap), k, divisor, bias, 1)" in EFFECTS
 
 
-def test_new_filter_aliases_registered():
+def test_blur_and_custom_filter_aliases_registered():
     assert "'box-blur': 'blur-box'" in EDITOR
     assert "'surface-blur': 'blur-surface'" in EDITOR
     assert "custom: 'other-custom'" in EDITOR

tests/test_procfs_scan_guard.py

@@ -12,6 +12,8 @@ exercising every procfs-touching code path on both a Linux and a non-Linux
 host. ``test_cookbook_stop_without_procfs.py`` covers the behaviour itself.
 """
 import ast
+
+import pytest
 from pathlib import Path
 
 REPO_ROOT = Path(__file__).resolve().parent.parent
@@ -75,37 +77,112 @@ def _scan_sites(tree: ast.AST) -> list[ast.Call]:
     return sites
 
 
-def _guard_lines(tree: ast.AST) -> list[int]:
+def _condition_requires_procfs(node: ast.AST, truth: bool) -> bool:
-    """Line numbers of calls that test whether procfs is present."""
+    """Whether this Boolean outcome proves a direct procfs check succeeded.
-    lines = []
+
-    for node in ast.walk(tree):
+    An ignored call, another function's check, or a check on only one possible
-        if not isinstance(node, ast.Call):
+    OR branch provides no proof. Keep unknown expressions conservative.
-            continue
+    """
-        func = node.func
+    if isinstance(node, ast.UnaryOp) and isinstance(node.op, ast.Not):
-        name = func.attr if isinstance(func, ast.Attribute) else getattr(func, "id", "")
+        return _condition_requires_procfs(node.operand, not truth)
-        if name not in _GUARD_FUNCS:
+    if isinstance(node, ast.BoolOp):
-            continue
+        facts = [_condition_requires_procfs(value, truth) for value in node.values]
-        subject_is_procfs = (
+        all_values_required = isinstance(node.op, ast.And) == truth
-            name in {"has_procfs", "is_wsl"}
+        return any(facts) if all_values_required else all(facts)
-            or (isinstance(func, ast.Attribute) and _is_procfs_root(func.value))
+    if not isinstance(node, ast.Call):
-            or any(_is_procfs_root(arg) for arg in node.args)
+        return False
-        )
+    func = node.func
-        if subject_is_procfs:
+    name = func.attr if isinstance(func, ast.Attribute) else getattr(func, "id", "")
-            lines.append(node.lineno)
+    subject_is_procfs = (
-    return lines
+        name == "has_procfs"
+        or (isinstance(func, ast.Attribute) and _is_procfs_root(func.value))
+        or any(_is_procfs_root(arg) for arg in node.args)
+    )
+    return truth and name in _GUARD_FUNCS and subject_is_procfs
 
 
-def _enclosing_scope(tree: ast.AST, node: ast.AST) -> ast.AST:
+def _guarded_scan_ids(tree: ast.AST) -> set[int]:
-    """Smallest function/module scope containing ``node``."""
+    """Follow conditional/early-exit paths instead of comparing line numbers.
-    best = tree
+
-    for candidate in ast.walk(tree):
+    Each function starts with no procfs assumption. Facts from a loop or try
-        if not isinstance(candidate, (ast.FunctionDef, ast.AsyncFunctionDef)):
+    body cannot escape to code which may run without that body completing.
-            continue
+    This intentionally requires direct checks; arbitrary aliases/call graphs
-        end = getattr(candidate, "end_lineno", None) or candidate.lineno
+    are not a proof that procfs exists at the enumeration site.
-        if candidate.lineno <= node.lineno <= end:
+    """
-            if best is tree or candidate.lineno > best.lineno:
+    scans = {id(site) for site in _scan_sites(tree)}
-                best = candidate
+    guarded = set()
-    return best
+
+    def expression(node, present):
+        if node is None:
+            return
+        if id(node) in scans and present:
+            guarded.add(id(node))
+        if isinstance(node, ast.BoolOp):
+            for value in node.values:
+                expression(value, present)
+                # Later AND operands run only after a true prefix; later OR
+                # operands run only after a false prefix.
+                present = present or _condition_requires_procfs(value, isinstance(node.op, ast.And))
+        elif isinstance(node, ast.IfExp):
+            expression(node.test, present)
+            expression(node.body, present or _condition_requires_procfs(node.test, True))
+            expression(node.orelse, present or _condition_requires_procfs(node.test, False))
+        elif isinstance(node, (ast.ListComp, ast.SetComp, ast.GeneratorExp, ast.DictComp)):
+            for generator in node.generators:
+                expression(generator.iter, present)
+                for condition in generator.ifs:
+                    expression(condition, present)
+                    present = present or _condition_requires_procfs(condition, True)
+            for attr in ("elt", "key", "value"):
+                expression(getattr(node, attr, None), present)
+        elif isinstance(node, ast.Lambda):
+            expression(node.body, False)
+        else:
+            for child in ast.iter_child_nodes(node):
+                expression(child, present)
+
+    def block(statements, present):
+        for statement in statements:
+            if isinstance(statement, (ast.FunctionDef, ast.AsyncFunctionDef)):
+                block(statement.body, False)
+                for value in statement.decorator_list + statement.args.defaults:
+                    expression(value, present)
+            elif isinstance(statement, ast.ClassDef):
+                block(statement.body, present)
+            elif isinstance(statement, ast.If):
+                expression(statement.test, present)
+                yes = block(statement.body, present or _condition_requires_procfs(statement.test, True))
+                no = block(statement.orelse, present or _condition_requires_procfs(statement.test, False))
+                continuing = [fact for fact in (yes, no) if fact is not None]
+                if not continuing:
+                    return None
+                present = all(continuing)
+            elif isinstance(statement, (ast.Return, ast.Raise, ast.Break, ast.Continue)):
+                for child in ast.iter_child_nodes(statement):
+                    expression(child, present)
+                return None
+            elif isinstance(statement, (ast.For, ast.AsyncFor, ast.While)):
+                condition = statement.test if isinstance(statement, ast.While) else statement.iter
+                expression(condition, present)
+                body_present = present or (isinstance(statement, ast.While) and _condition_requires_procfs(condition, True))
+                block(statement.body, body_present)
+                block(statement.orelse, present)
+            elif isinstance(statement, (ast.Try, getattr(ast, "TryStar", ast.Try))):
+                block(statement.body, present)
+                block(statement.orelse, present)
+                block(statement.finalbody, present)
+                for handler in statement.handlers:
+                    block(handler.body, present)
+            elif isinstance(statement, (ast.With, ast.AsyncWith)):
+                for item in statement.items:
+                    expression(item.context_expr, present)
+                block(statement.body, present)
+            else:
+                expression(statement, present)
+        return present
+
+    block(tree.body, False)
+    return guarded
 
 
 def _app_python_files() -> list[Path]:
@@ -139,12 +216,10 @@ def _collect_sites() -> tuple[list[str], list[str]]:
         sites = _scan_sites(tree)
         if not sites:
             continue
-        guards = _guard_lines(tree)
+        guards = _guarded_scan_ids(tree)
         for site in sites:
-            scope = _enclosing_scope(tree, site)
-            start = getattr(scope, "lineno", 0)
             label = f"{path.relative_to(REPO_ROOT)}:{site.lineno}"
-            if any(start <= g < site.lineno for g in guards):
+            if id(site) in guards:
                 guarded.append(label)
             else:
                 unguarded.append(label)
@@ -154,7 +229,7 @@ def _collect_sites() -> tuple[list[str], list[str]]:
 def test_every_procfs_scan_is_guarded_by_an_existence_check():
     _guarded, unguarded = _collect_sites()
     assert not unguarded, (
-        "procfs pid scans with no existence check in the enclosing function — "
+        "procfs pid scans without an effective conditional existence guard — "
         "these raise FileNotFoundError on macOS and Windows: "
         + ", ".join(unguarded)
     )
@@ -176,3 +251,49 @@ def test_the_guard_detector_still_sees_the_known_scans():
         f"root was renamed. Found: {sorted(found)}"
     )
     assert len(found) >= 3, f"expected at least 3 procfs scans, found {sorted(found)}"
+
+
+@pytest.mark.parametrize("body", [
+    'Path("/proc").exists(); os.listdir("/proc")',
+    'if Path("/proc").exists():\n    pass\nos.listdir("/proc")',
+    'if not Path("/proc").exists():\n    os.listdir("/proc")',
+    'if ready or Path("/proc").exists():\n    os.listdir("/proc")',
+    'if ready:\n    Path("/proc").exists()\nos.listdir("/proc")',
+    'os.listdir("/proc"); Path("/proc").exists()',
+    'if Path("/tmp").exists():\n    os.listdir("/proc")',
+    'def other():\n    Path("/proc").exists()\nos.listdir("/proc")',
+    'if not has_procfs():\n    pass\nos.listdir("/proc")',
+    'for x in []:\n    if not has_procfs():\n        return\nos.listdir("/proc")',
+    'if has_procfs():\n    return\nelse:\n    os.listdir("/proc")',
+    '[pid for pid in os.listdir("/proc") if has_procfs()]',
+], ids=["ignored", "expired-branch", "inverted", "unsafe-or", "sibling-branch",
+        "too-late", "wrong-path", "other-function", "no-early-exit", "loop-may-not-run",
+        "wrong-else", "late-comprehension-filter"])
+def test_guard_detector_rejects_ineffective_checks(body):
+    tree = ast.parse("def scan():\n" + "\n".join("    " + line for line in body.splitlines()))
+    sites = _scan_sites(tree)
+    assert sites, "negative control must contain a recognized enumeration"
+    assert any(id(site) not in _guarded_scan_ids(tree) for site in sites)
+
+
+@pytest.mark.parametrize("body", [
+    'if Path("/proc").exists():\n    os.listdir("/proc")',
+    'if not Path("/proc").exists():\n    return\nos.listdir("/proc")',
+    'if not has_procfs():\n    raise RuntimeError()\nos.listdir(PROC_ROOT)',
+    'if has_procfs():\n    pass\nelse:\n    return\nPROC_ROOT.iterdir()',
+    'if ready and has_procfs():\n    os.scandir("/proc")',
+    'if not has_procfs() or disabled:\n    return\nPROC_ROOT.glob("*")',
+    'if sys.platform == "linux" and has_procfs():\n    PROC_ROOT.iterdir()',
+    'for item in items:\n    if not has_procfs():\n        continue\n    os.listdir("/proc")',
+    'if os.path.isdir("/proc"):\n    os.listdir("/proc")',
+    'if has_procfs() and list(PROC_ROOT.iterdir()):\n    pass',
+    'if not has_procfs() or list(PROC_ROOT.iterdir()):\n    pass',
+    '[pid for item in items if has_procfs() for pid in os.listdir("/proc")]',
+], ids=["positive-branch", "early-return", "early-raise", "else-exits", "and",
+        "negative-or", "platform-and-procfs", "loop-continue", "isdir",
+        "short-circuit-and", "short-circuit-or", "guarded-comprehension"])
+def test_guard_detector_preserves_effective_checks(body):
+    tree = ast.parse("def scan():\n" + "\n".join("    " + line for line in body.splitlines()))
+    sites = _scan_sites(tree)
+    assert sites, "positive control must contain a recognized enumeration"
+    assert all(id(site) in _guarded_scan_ids(tree) for site in sites)