ModuleGraph: Stop bumping the graph revision on story-index invalidation

code/core/src/core-server/change-detection/change-detection-service.test.ts

@@ -1085,10 +1085,10 @@ describe('ChangeDetectionService', () => {
     await expect(service.dispose()).resolves.toBeUndefined();
   });
 
-  it('rescans the working tree when the story index is invalidated', async () => {
+  it('rescans the working tree when the module graph revision advances', async () => {
     // Graph-side reconciliation (replaying add/unlink, the refreshInFlight guard) is covered by
-    // module-graph-engine.test.ts; here we assert the status side of the seam: an index
-    // invalidation re-runs the git-diff scan.
+    // module-graph-engine.test.ts; here we assert the status side of the seam: a graph revision
+    // bump (from a file change or story-index reconciliation) re-runs the git-diff scan.
     const reverseIndex = buildReverseIndex([]);
     installDependencyGraphMocks(reverseIndex);
 

code/core/src/core-server/change-detection/change-detection.test-helpers.ts

@@ -137,7 +137,6 @@ export function createWiredChangeDetection(
     workingDir: options.workingDir,
     onSnapshot: () => moduleGraphMockRef.current?.applySnapshot(),
     onUpdate: ({ bumpedStoryFiles }) => moduleGraphMockRef.current?.applyUpdate(bumpedStoryFiles),
-    onStoryIndexInvalidated: () => moduleGraphMockRef.current?.bumpGraphRevision(),
     onError: (error) => moduleGraphMockRef.current?.applyError(error),
     onUnavailable: (reason, error) => moduleGraphMockRef.current?.applyUnavailable(reason, error),
   });

code/core/src/shared/open-service/services/module-graph/definition.ts

@@ -257,19 +257,6 @@ export const moduleGraphServiceDef = defineService({
         });
       },
     },
-    _bumpGraphRevision: {
-      internal: true,
-      description:
-        'Bumps the graph revision when the story index invalidates without an immediate graph snapshot/update.',
-      input: noInputSchema,
-      output: v.void(),
-      handler: async (_input, ctx) => {
-        ctx.self.setState((state) => {
-          state.graphRevision += 1;
-          state.latestChangedStoryFiles = [];
-        });
-      },
-    },
     _setStatus: {
       internal: true,
       description:

code/core/src/shared/open-service/services/module-graph/engine/module-graph-engine.test.ts

@@ -28,7 +28,6 @@ function setup(options?: {
   const callbacks = {
     onSnapshot: vi.fn(),
     onUpdate: vi.fn(),
-    onStoryIndexInvalidated: vi.fn(),
     onError: vi.fn(),
     onUnavailable: vi.fn(),
   };
@@ -230,8 +229,32 @@ describe('ModuleGraphEngine', () => {
     await vi.runAllTimersAsync();
 
     expect(patchSpy).toHaveBeenCalledWith({ kind: 'add', path: '/repo/src/B.stories.tsx' });
-    // The index changed, so the service wrapper is notified to bump graph revision.
-    expect(callbacks.onStoryIndexInvalidated).toHaveBeenCalled();
+    // The replayed add flows through the normal patch path, so the new story is reported as a
+    // targeted update — no separate untargeted index-invalidation bump is needed.
+    expect(callbacks.onUpdate).toHaveBeenCalledWith(
+      expect.objectContaining({ bumpedStoryFiles: ['./src/B.stories.tsx'] })
+    );
+  });
+
+  it('does not emit an update when an invalidation leaves the story set unchanged', async () => {
+    // A content-only story edit (or a config invalidation) re-fires the index without changing the
+    // set of story files. The builder's own file-change event carries any content change; the
+    // invalidation itself must not produce an untargeted update.
+    installDependencyGraphMocks(buildReverseIndex([]));
+    const { service, adapter, callbacks } = setup({
+      storyIndex: createStoryIndex([
+        { storyId: 'a--default', importPath: './src/A.stories.tsx', title: 'A' },
+      ]),
+    });
+
+    service.start(adapter);
+    await vi.runAllTimersAsync();
+    expect(callbacks.onUpdate).not.toHaveBeenCalled();
+
+    service.onStoryIndexInvalidated();
+    await vi.runAllTimersAsync();
+
+    expect(callbacks.onUpdate).not.toHaveBeenCalled();
   });
 
   it('guards duplicate onStoryIndexInvalidated so a newly-added story is replayed only once', async () => {

code/core/src/shared/open-service/services/module-graph/engine/module-graph-engine.ts

@@ -30,8 +30,6 @@ export interface ModuleGraphEngineOptions {
   onError?: (error: Error) => void;
   /** Fired when the builder adapter reports a startup failure. */
   onUnavailable?: (reason: string, error?: Error) => void;
-  /** Fired when the story index invalidates, even if no graph edges changed. */
-  onStoryIndexInvalidated?: () => void;
   /** Mirrors the built reverse index into the `core/module-graph` open service. */
   onSnapshot?: (storiesByFile: ReturnType<typeof reverseIndexToStoriesByFile>) => void;
   /** Mirrors state after each settled patch; includes story files whose graph may have changed. */
@@ -271,9 +269,6 @@ export class ModuleGraphEngine {
           this.refreshInFlight = false;
         });
     }
-    // The story index changed even when no story files were added/removed (e.g. a story renamed
-    // within a file); signal consumers so derived state is recomputed.
-    this.options.onStoryIndexInvalidated?.();
   }
 
   /**

code/core/src/shared/open-service/services/module-graph/server.test.ts

@@ -6,6 +6,7 @@ import { clearRegistry } from '../../server.ts';
 import {
   buildReverseIndex,
   createMockAdapter,
+  createStoryIndex,
   installDependencyGraphMocks,
   registerTestModuleGraphService,
 } from './module-graph.test-helpers.ts';
@@ -356,21 +357,6 @@ describe('module-graph open service', () => {
       });
     });
 
-    it('clears story files but keeps the current revision after _bumpGraphRevision', async () => {
-      const runtime = registerBareModuleGraph();
-
-      await runtime.commands._applyGraphUpdate({
-        storiesByFile: {},
-        bumpedStoryFiles: ['./src/Button.stories.tsx'],
-      });
-      await runtime.commands._bumpGraphRevision(undefined);
-
-      expect(runtime.queries.getLatestStoryChanges(undefined)).toEqual({
-        revision: 2,
-        storyFiles: [],
-      });
-    });
-
     it('notifies subscribers when the latest change set updates', async () => {
       const runtime = registerBareModuleGraph();
       const seen: Array<{ revision: number; storyFiles: string[] }> = [];
@@ -433,22 +419,6 @@ describe('module-graph open service', () => {
       ).toBe(1);
       expect(runtime.queries.getGraphRevision({ storyFiles: ['src/Button.stories.tsx'] })).toBe(1);
     });
-
-    it('advances watch-all but not scoped reads on a bare revision bump', async () => {
-      const runtime = registerBareModuleGraph();
-      await runtime.commands._applyGraphSnapshot({
-        storiesByFile: { './src/Button.tsx': { './src/Button.stories.tsx': 1 } },
-      });
-
-      await runtime.commands._bumpGraphRevision(undefined);
-
-      // Index reconciliation advances the global (watch-all) revision...
-      expect(runtime.queries.getGraphRevision(undefined)).toBe(1);
-      // ...but is not attributed to any specific story.
-      expect(runtime.queries.getGraphRevision({ storyFiles: ['./src/Button.stories.tsx'] })).toBe(
-        0
-      );
-    });
   });
 
   describe('getGraphRevision subscription', () => {
@@ -522,18 +492,33 @@ describe('module-graph open service', () => {
     });
 
     // Must run last: it resolves the process-global adapter promise, which cannot be un-resolved.
-    it('builds the graph once the adapter is provided and mirrors it into service state', async () => {
+    it('builds the graph from the adapter and turns index invalidations into targeted updates', async () => {
       const reverseIndex = buildReverseIndex([
         ['/repo/src/Button.tsx', '/repo/src/Button.stories.tsx', 1],
       ]);
       installDependencyGraphMocks(reverseIndex);
 
-      const channel = { on: vi.fn(() => () => undefined), emit: vi.fn() };
+      const baselineIndex = createStoryIndex([
+        { storyId: 'button--primary', importPath: './src/Button.stories.tsx', title: 'Button' },
+      ]);
+      const indexWithCard = createStoryIndex([
+        { storyId: 'button--primary', importPath: './src/Button.stories.tsx', title: 'Button' },
+        { storyId: 'card--primary', importPath: './src/Card.stories.tsx', title: 'Card' },
+      ]);
+      // Build reads the baseline; the first invalidation re-reads it unchanged, the second adds Card.
+      const getIndex = vi
+        .fn()
+        .mockResolvedValueOnce(baselineIndex)
+        .mockResolvedValueOnce(baselineIndex)
+        .mockResolvedValue(indexWithCard);
+
+      const on = vi.fn<(event: string, listener: () => void) => () => void>(() => () => undefined);
+      const channel = { on, emit: vi.fn() };
       const { adapter } = createMockAdapter({ resolveConfig: { projectRoot: '/repo' } });
 
       const runtime = registerModuleGraphService({
         channel: channel as never,
-        getIndex: vi.fn().mockResolvedValue({ v: 5, entries: {} }),
+        getIndex,
         workingDir: '/repo',
       });
 
@@ -548,6 +533,30 @@ describe('module-graph open service', () => {
       expect(runtime.queries.getStoriesForFiles({ files: ['/repo/src/Button.tsx'] })).toEqual([
         [{ storyFile: './src/Button.stories.tsx', depth: 1 }],
       ]);
+
+      const invalidate = channel.on.mock.calls.find(
+        ([event]) => event === STORY_INDEX_INVALIDATED
+      )?.[1];
+      expect(invalidate).toBeTypeOf('function');
+
+      // An invalidation that does not change the story set must not advance the revision on its own
+      // (no untargeted bump, no clobbered change set).
+      invalidate!();
+      await runtime.commands._waitForSettledEngine(undefined);
+      expect(runtime.queries.getGraphRevision(undefined)).toBe(0);
+      expect(runtime.queries.getLatestStoryChanges(undefined)).toEqual({
+        revision: 0,
+        storyFiles: [],
+      });
+
+      // A newly-indexed story is reconciled and reported as a targeted change.
+      invalidate!();
+      await vi.waitFor(() => {
+        expect(runtime.queries.getLatestStoryChanges(undefined)).toEqual({
+          revision: 1,
+          storyFiles: ['./src/Card.stories.tsx'],
+        });
+      });
     });
   });
 });

code/core/src/shared/open-service/services/module-graph/server.ts

@@ -78,9 +78,6 @@ export function registerModuleGraphService(options: RegisterModuleGraphServiceOp
     onUpdate: ({ storiesByFile, bumpedStoryFiles }) => {
       void runtime.commands._applyGraphUpdate({ storiesByFile, bumpedStoryFiles });
     },
-    onStoryIndexInvalidated: () => {
-      void runtime.commands._bumpGraphRevision(undefined);
-    },
     onError: (error) => {
       void runtime.commands._setStatus({ value: 'error', error: errorToErrorLike(error) });
     },