fix(native): never reuse a native discovery session for edited inputs

Document that a missing session means readers use the Python objects, and drop the session from the inputs each Rule fix pass lints.

Author: kvlonge

src/sqlbuild/compiler/discovery/models.py

@@ -639,6 +639,11 @@ class DiscoveredDeclarationFiles:
     macro_files: tuple[DiscoveredMacroFile, ...]
     adapter_file: DiscoveredAdapterFile | None
     native_session: NativeDiscoverySession | None = field(default=None, compare=False, repr=False)
+    """The native session that read these declaration files, for later native stages.
+
+    `None` means no session: readers must use the Python objects. Any copy that changes a
+    discovered collection must set it to `None` so it never describes other files.
+    """
 
 
 @dataclass(frozen=True)
@@ -674,7 +679,11 @@ class DiscoveredProjectInputs:
     providers: tuple[DiscoveredProvider, ...] = field(default_factory=tuple)
     adapter_file: DiscoveredAdapterFile | None = None
     native_session: NativeDiscoverySession | None = field(default=None, compare=False, repr=False)
-    """The native discovery session that read the declaration files, for later native stages."""
+    """The native session that read these declaration files, for later native stages.
+
+    `None` means no session: readers must use the Python objects. Any copy that changes a
+    discovered collection must set it to `None` so it never describes other files.
+    """
 
 
 @dataclass(frozen=True)

src/sqlbuild/lint/_helpers/fixes.py

@@ -439,4 +439,5 @@ def _updated_inputs(
             else model
             for model in inputs.model_files
         ),
+        native_session=None,
     )

tests/integration/src/sqlbuild/cli/commands/main/_test_types.py

@@ -1050,3 +1050,13 @@ class InferredFreshnessCliTestCase:
     description: str
     sources_yaml: str
     expected_sources: tuple[tuple[object, ...], ...]
+
+
+@dataclass(frozen=True)
+class FixSessionTestCase:
+    """A Rule fix under an engine whose discovery retains a native session."""
+
+    description: str
+    engine: str
+    expected_original_sessions: tuple[bool, ...]
+    expected_fix_pass_sessions: frozenset[bool]

tests/integration/src/sqlbuild/cli/commands/main/helpers.py

@@ -34,6 +34,8 @@
 )
 from sqlbuild.compiler.planner.exceptions import NativeSqlTestPlanningError
 from sqlbuild.compiler.planner.models import NativeSqlTestArtifact
+from sqlbuild.lint._helpers import fixes as lint_fixes
+from sqlbuild.lint.main import run_format as run_format_module
 from tests.integration.src.sqlbuild.cli.commands.main._test_types import (
     RepeatedJsonParseTestCase,
 )
@@ -189,6 +191,27 @@ def recorded_plan(**kwargs: Any) -> PlannedStaticSqlTests:
     return threads
 
 
+def record_fix_sessions(monkeypatch: pytest.MonkeyPatch) -> tuple[list[bool], list[bool]]:
+    """Record whether the inputs a Rule fix starts from, and each fix pass lints, hold a session."""
+
+    original: list[bool] = []
+    passes: list[bool] = []
+    plan: Callable[..., Any] = run_format_module.plan_rule_fixes
+    lint: Callable[..., Any] = lint_fixes.run_lint
+
+    def recorded_plan(**kwargs: Any) -> Any:
+        original.append(getattr(kwargs["discovered_inputs"], "native_session", None) is not None)
+        return plan(**kwargs)
+
+    def recorded_lint(**kwargs: Any) -> Any:
+        passes.append(kwargs["discovered_inputs"].native_session is not None)
+        return lint(**kwargs)
+
+    monkeypatch.setattr(run_format_module, "plan_rule_fixes", recorded_plan)
+    monkeypatch.setattr(lint_fixes, "run_lint", recorded_lint)
+    return original, passes
+
+
 def skip_artifact_preparation(self: PreparedCompileArtifacts, **kwargs: object) -> None:
     """Disable background preparation so the write phase plans SQL tests inline."""
 

tests/integration/src/sqlbuild/cli/commands/main/test_format_fix.py

@@ -10,13 +10,16 @@
 import pytest
 
 from sqlbuild.cli.commands.main.entrypoint.entry import main
+from sqlbuild.compiler.frontier.constants import COMPILER_ENGINE_ENV_VAR
 from tests.integration.src.sqlbuild.cli.commands.main._test_types import (
+    FixSessionTestCase,
     FormatCompileIntegrationTestCase,
     SemanticFixTestCase,
     UnusedOutputDifferentialCase,
 )
 from tests.integration.src.sqlbuild.cli.commands.main.helpers import (
     built_model_rows,
+    record_fix_sessions,
     rule_fix_statuses,
 )
 
@@ -31,6 +34,41 @@
 )
 
 
+@pytest.mark.parametrize(
+    "test_case",
+    [
+        FixSessionTestCase(
+            description="preview fix passes drop the session of the unfixed files",
+            engine="native-preview",
+            expected_original_sessions=(True,),
+            expected_fix_pass_sessions=frozenset({False}),
+        ),
+    ],
+    ids=lambda case: case.description,
+)
+def test_given_retained_native_session_when_fixing_then_fix_passes_never_reuse_it(
+    test_case: FixSessionTestCase,
+    tmp_path: Path,
+    capsys: pytest.CaptureFixture[str],
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    (tmp_path / "sqlbuild_project.toml").write_text('name = "orders"\nadapter = "duckdb"\n')
+    model: Path = tmp_path / "models" / "orders.sql"
+    model.parent.mkdir()
+    model.write_text(
+        'MODEL (description "Orders");\nSELECT 1 AS order_id UNION SELECT 2 AS order_id\n'
+    )
+    monkeypatch.setenv(COMPILER_ENGINE_ENV_VAR, test_case.engine)
+    original, passes = record_fix_sessions(monkeypatch)
+
+    exit_code: int = main(["--project-dir", str(tmp_path), "format", "--fix", "--json"])
+
+    capsys.readouterr()
+    assert exit_code == 0
+    assert tuple(original) == test_case.expected_original_sessions
+    assert frozenset(passes) == test_case.expected_fix_pass_sessions
+
+
 @pytest.mark.parametrize(
     "test_case",
     [FormatCompileIntegrationTestCase("bare union", "UNION DISTINCT")],