fix(suppressions): bind multiline inline ignores to decorated declaration headers consistently

Author: orenlab

codeclone/suppressions.py

@@ -158,6 +158,24 @@ def extract_suppression_directives(
     )
 
 
+def _declaration_inline_lines(target: DeclarationTarget) -> tuple[int, ...]:
+    end_line = target.declaration_end_line or target.start_line
+    if end_line <= 0 or end_line == target.start_line:
+        return (target.start_line,)
+    return (target.start_line, end_line)
+
+
+def _bound_inline_rules(
+    *,
+    target: DeclarationTarget,
+    inline_rules_by_line: Mapping[int, tuple[str, ...]],
+) -> tuple[str, ...]:
+    rules: tuple[str, ...] = ()
+    for line_no in _declaration_inline_lines(target):
+        rules = _merge_rules(rules, inline_rules_by_line.get(line_no, ()))
+    return rules
+
+
 def bind_suppressions_to_declarations(
     *,
     directives: Sequence[SuppressionDirective],
@@ -177,10 +195,12 @@ def bind_suppressions_to_declarations(
 
     bindings: list[SuppressionBinding] = []
     for target in declarations:
-        inline_binding_line = target.declaration_end_line or target.start_line
         bound_rules = _merge_rules(
             leading_rules_by_line.get(target.start_line - 1, ()),
-            inline_rules_by_line.get(inline_binding_line, ()),
+            _bound_inline_rules(
+                target=target,
+                inline_rules_by_line=inline_rules_by_line,
+            ),
         )
         if not bound_rules:
             continue

tests/test_cli_inprocess.py

@@ -3803,14 +3803,11 @@ def fn(x):
     assert any("sf" in entry for entry in files_after.values())
 
 
-def test_cli_dead_code_suppression_is_stable_between_plain_and_json_runs(
-    tmp_path: Path,
-    monkeypatch: pytest.MonkeyPatch,
-) -> None:
-    _write_python_module(
-        tmp_path,
-        "models.py",
-        """\
+@pytest.mark.parametrize(
+    ("source", "suppressed_count"),
+    [
+        (
+            """\
 class Settings:  # codeclone: ignore[dead-code]
     @validator("field")
     @classmethod
@@ -3820,6 +3817,41 @@ def validate_config_version(
     ) -> str | None:  # codeclone: ignore[dead-code]
         return value
 """,
+            2,
+        ),
+        (
+            """\
+class Settings:  # codeclone: ignore[dead-code]
+    @field_validator("trusted_proxy_ips", "additional_telegram_ip_ranges")
+    @classmethod
+    def validate_trusted_proxy_ips(  # codeclone: ignore[dead-code]
+        cls,
+        value: list[str] | None,
+    ) -> list[str] | None:
+        return value
+
+    @model_validator(mode="before")
+    @classmethod
+    def migrate_config_if_needed(  # codeclone: ignore[dead-code]
+        cls,
+        values: dict[str, object],
+    ) -> dict[str, object]:
+        return values
+""",
+            3,
+        ),
+    ],
+)
+def test_cli_dead_code_suppression_is_stable_between_plain_and_json_runs(
+    tmp_path: Path,
+    monkeypatch: pytest.MonkeyPatch,
+    source: str,
+    suppressed_count: int,
+) -> None:
+    _write_python_module(
+        tmp_path,
+        "models.py",
+        source,
     )
     json_out = tmp_path / "report.json"
     cache_path = tmp_path / "cache.json"
@@ -3854,7 +3886,11 @@ def validate_config_version(
     )
     payload = json.loads(json_out.read_text("utf-8"))
     dead_code = payload["metrics"]["families"]["dead_code"]
-    assert dead_code["summary"] == {"total": 0, "high_confidence": 0, "suppressed": 2}
+    assert dead_code["summary"] == {
+        "total": 0,
+        "high_confidence": 0,
+        "suppressed": suppressed_count,
+    }
 
     _run_main(
         monkeypatch,

tests/test_extractor.py

@@ -756,6 +756,44 @@ def orphan(self) -> int:
     assert tuple(item.qualname for item in dead) == ("pkg.mod:Settings.orphan",)
 
 
+def test_dead_code_binds_inline_suppression_on_multiline_header_start_line() -> None:
+    src = """
+class Settings:  # codeclone: ignore[dead-code]
+    @field_validator("trusted_proxy_ips", "additional_telegram_ip_ranges")
+    @classmethod
+    def validate_trusted_proxy_ips(  # codeclone: ignore[dead-code]
+        cls,
+        value: list[str] | None,
+    ) -> list[str] | None:
+        return value
+
+    @model_validator(mode="before")
+    @classmethod
+    def migrate_config_if_needed(  # codeclone: ignore[dead-code]
+        cls,
+        values: dict[str, object],
+    ) -> dict[str, object]:
+        return values
+
+    def orphan(self) -> int:
+        return 1
+"""
+    _, _, _, _, file_metrics, _ = extractor.extract_units_and_stats_from_source(
+        source=src,
+        filepath="pkg/mod.py",
+        module_name="pkg.mod",
+        cfg=NormalizationConfig(),
+        min_loc=1,
+        min_stmt=1,
+    )
+    dead = find_unused(
+        definitions=file_metrics.dead_candidates,
+        referenced_names=file_metrics.referenced_names,
+        referenced_qualnames=file_metrics.referenced_qualnames,
+    )
+    assert tuple(item.qualname for item in dead) == ("pkg.mod:Settings.orphan",)
+
+
 def test_collect_dead_candidates_and_extract_skip_classes_without_lineno(
     monkeypatch: pytest.MonkeyPatch,
 ) -> None:

tests/test_suppressions.py

@@ -240,6 +240,108 @@ def keep(
     )
 
 
+@pytest.mark.parametrize(
+    ("source", "declaration"),
+    [
+        (
+            """
+@decorator
+def keep(  # codeclone: ignore[dead-code]
+    arg: int,
+) -> int:
+    return arg
+""".strip(),
+            DeclarationTarget(
+                filepath="pkg/mod.py",
+                qualname="pkg.mod:keep",
+                start_line=2,
+                end_line=5,
+                kind="function",
+                declaration_end_line=4,
+            ),
+        ),
+        (
+            """
+async def keep_async(  # codeclone: ignore[dead-code]
+    arg: int,
+) -> int:
+    return arg
+""".strip(),
+            DeclarationTarget(
+                filepath="pkg/mod.py",
+                qualname="pkg.mod:keep_async",
+                start_line=1,
+                end_line=4,
+                kind="function",
+                declaration_end_line=3,
+            ),
+        ),
+        (
+            """
+class Demo(  # codeclone: ignore[dead-code]
+    Base,
+):
+    pass
+""".strip(),
+            DeclarationTarget(
+                filepath="pkg/mod.py",
+                qualname="pkg.mod:Demo",
+                start_line=1,
+                end_line=4,
+                kind="class",
+                declaration_end_line=3,
+            ),
+        ),
+    ],
+)
+def test_bind_suppressions_supports_inline_on_multiline_declaration_start_line(
+    source: str,
+    declaration: DeclarationTarget,
+) -> None:
+    directives = extract_suppression_directives(source)
+    bindings = bind_suppressions_to_declarations(
+        directives=directives,
+        declarations=(declaration,),
+    )
+    assert bindings == (
+        SuppressionBinding(
+            filepath=declaration.filepath,
+            qualname=declaration.qualname,
+            start_line=declaration.start_line,
+            end_line=declaration.end_line,
+            kind=declaration.kind,
+            rules=("dead-code",),
+        ),
+    )
+
+
+def test_bind_suppressions_ignores_inline_comment_on_middle_signature_line() -> None:
+    source = """
+def keep(
+    arg: int,  # codeclone: ignore[dead-code]
+) -> int:
+    return arg
+""".strip()
+    directives = extract_suppression_directives(source)
+    declarations = (
+        DeclarationTarget(
+            filepath="pkg/mod.py",
+            qualname="pkg.mod:keep",
+            start_line=1,
+            end_line=4,
+            kind="function",
+            declaration_end_line=3,
+        ),
+    )
+    assert (
+        bind_suppressions_to_declarations(
+            directives=directives,
+            declarations=declarations,
+        )
+        == ()
+    )
+
+
 @pytest.mark.parametrize(
     ("source", "declaration"),
     [