pipe/test/state_flow_test.dart

import 'package:pipe/pipe.dart';
import 'package:test/test.dart';

const String fixturePath = 'test/fixtures/stuck_loading';

void main() {
  late Project project;
  late ResolutionRun run;
  late StateFlow flow;
  late FindingReport report;

  setUpAll(() async {
    project = await loadProject(fixturePath);
    run = await resolveProject(project, concurrency: 1);
    flow = buildStateFlow(project, run.outcomes);
    report = runChecks(flow: flow);
  });

  tearDownAll(() async {
    await run.dispose();
  });

  test('fixture resolves with zero analyzer errors', () {
    final failures = run.outcomes.where((o) => !o.resolved).toList();
    expect(
      failures,
      isEmpty,
      reason: failures.map((f) => '${f.path}: ${f.failure}').join('\n'),
    );

    // Resolution succeeding is not the same as the fixture being valid: a unit
    // can resolve while containing compile errors, which would silently distort
    // the IR every rule test depends on. `dart analyze` cannot catch this because
    // test/fixtures/** is excluded from the repo's analysis_options, so it is
    // asserted here from the analyzer's own diagnostics.
    final errors = <String>[];
    for (final outcome in run.outcomes) {
      for (final diagnostic in outcome.diagnostics) {
        if (diagnostic.severity.name != 'error') continue;
        errors.add(
          '${outcome.path}:${outcome.unit?.lineInfo.getLocation(diagnostic.offset).lineNumber} '
          '${diagnostic.diagnosticCode.lowerCaseName}: ${diagnostic.message}',
        );
      }
    }
    expect(errors, isEmpty, reason: errors.join('\n'));
  });

  test('builds the state union and its variants', () {
    final union = flow.unions.firstWhere((u) => u.name == 'ItemState');
    expect(union.owner, 'ItemBloc');
    expect(
      union.variants.map((v) => v.name),
      containsAll(<String>['ItemLoading', 'ItemLoaded', 'ItemError']),
    );
    expect(union.style, UnionStyle.abstract);
  });

  test('loading-not-reset fires on the swallowed loading path', () {
    final hits = report.findings
        .where((finding) => finding.rule == ruleLoadingNotReset)
        .toList();
    expect(hits, isNotEmpty);
    // Every firing site is in the fixture's bad handlers/catches, and all of
    // them are high confidence warnings.
    expect(
      hits.every((f) => f.location.contains('item_bloc.dart')),
      isTrue,
      reason: 'unexpected firing site: ${hits.map((f) => f.location).toList()}',
    );
    expect(hits.every((f) => f.confidence == 'high'), isTrue);
    expect(hits.every((f) => f.severity == PipeSeverity.warning), isTrue);
  });

  test('does not fire where the catch resolves the loading state', () {
    // GuardedCubit emits a loading variant and awaits inside a try whose catch
    // emits a terminal state, so reporting it would be a false positive. This is
    // the precise form of the old "only one finding" assertion, which stopped
    // proving anything once the fixture gained a second bad site.
    final owners = report.findings
        .where((f) => f.rule == ruleLoadingNotReset)
        .map((f) => f.data['owner'])
        .toSet();
    expect(owners, isNot(contains('GuardedCubit')));
    expect(owners, contains('ItemBloc'));
  });

  test('emitted-not-rendered reports variants no UI consumes', () {
    final hits = report.findings
        .where((finding) => finding.rule == ruleEmittedNotRendered)
        .toList();
    expect(hits, isNotEmpty);
    expect(hits.map((f) => f.data['union']).toSet(), contains('ItemState'));
    // ItemState has no UI observing it, so those findings are high confidence.
    final itemState = hits.where(
      (finding) => finding.data['union'] == 'ItemState',
    );
    expect(itemState, isNotEmpty);
    expect(itemState.every((f) => f.confidence == 'high'), isTrue);
  });

  test('event-without-handler catches a dispatch with no registration', () {
    final hits = report.findings
        .where((finding) => finding.rule == ruleEventWithoutHandler)
        .toList();
    // ItemBloc registers handlers for both of its events, and SyncBloc/UploadBloc
    // cover their other events through base and group handlers, so the only
    // reports must be the two deliberate gaps.
    expect(
      {for (final hit in hits) '${hit.data['owner']}.${hit.data['event']}'},
      {'GapBloc.UnhandledTap', 'UploadBloc.UploadAbandoned'},
    );
    expect(hits, hasLength(2));
  });

  test('every finding carries evidence', () {
    for (final finding in report.findings) {
      expect(finding.evidence, isNotEmpty, reason: finding.message);
      expect(finding.remediation, isNotNull, reason: finding.message);
      expect(finding.file, isNotNull, reason: finding.message);
    }
  });
}