feat: support Storybook stories with title but no exported component

api/src/rpcs.ts

@@ -54,5 +54,5 @@ export type ComponentInfo =
         end: number;
         value: SerializableValue;
       } | null;
-      associatedComponentId: string;
+      associatedComponentId: string | null;
     };

core/src/detect-components.ts

@@ -184,7 +184,7 @@ export function detectedComponentToApiComponent(
             kind: "story",
             args: component.info.args,
             associatedComponentId:
-              component.info.associatedComponent.componentId,
+              component.info.associatedComponent?.componentId || null,
           },
   };
 }

core/src/index.ts

@@ -5,7 +5,7 @@ import type {
   TypeAnalyzer,
   ValueType,
 } from "@previewjs/type-analyzer";
-import { createTypeAnalyzer } from "@previewjs/type-analyzer";
+import { createTypeAnalyzer, UNKNOWN_TYPE } from "@previewjs/type-analyzer";
 import type { Reader } from "@previewjs/vfs";
 import express from "express";
 import fs from "fs-extra";
@@ -116,7 +116,13 @@ export async function createWorkspace({
       if (component.info.kind === "component") {
         analyze = component.info.analyze;
       } else {
-        analyze = component.info.associatedComponent.analyze;
+        analyze =
+          component.info.associatedComponent?.analyze ||
+          (() =>
+            Promise.resolve({
+              propsType: UNKNOWN_TYPE,
+              types: {},
+            }));
       }
       logger.debug(`Analyzing ${component.info.kind}: ${componentId}`);
       const { propsType: props, types: componentTypes } = await analyze();
@@ -132,7 +138,7 @@ export async function createWorkspace({
                 kind: "story",
                 args: component.info.args,
                 associatedComponentId:
-                  component.info.associatedComponent.componentId,
+                  component.info.associatedComponent?.componentId || null,
               },
         props,
       };

core/src/plugins/framework.ts

@@ -54,7 +54,7 @@ export type ComponentTypeInfo =
         end: number;
         value: SerializableValue;
       } | null;
-      readonly associatedComponent: StoryAssociatedComponent;
+      readonly associatedComponent: StoryAssociatedComponent | null;
     };
 
 export type StoryAssociatedComponent = {

framework-plugins/preact/src/extract-component.spec.ts

@@ -284,7 +284,7 @@ export default () => {
     expect(extract(APP_TSX)).toMatchObject([]);
   });
 
-  it("detects CSF1 stories", async () => {
+  it("detects CSF1 stories (exported with component)", async () => {
     memoryReader.updateFile(
       APP_STORIES_TSX,
       `
@@ -320,27 +320,62 @@ export const NotStory = (props) => <Button {...props} />;
         },
       },
     ]);
-    if (extractedStories[0]?.info.kind !== "story") {
+    const storyInfo = extractedStories[0]?.info;
+    if (storyInfo?.kind !== "story" || !storyInfo.associatedComponent) {
       throw new Error();
     }
-    expect(
-      await extractedStories[0].info.associatedComponent.analyze()
-    ).toEqual({
+    expect(await storyInfo.associatedComponent.analyze()).toEqual({
       propsType: objectType({
         label: STRING_TYPE,
       }),
       types: {},
     });
   });
 
-  it("detects CSF2 stories", async () => {
+  it("detects CSF1 stories (exported with title)", async () => {
     memoryReader.updateFile(
       APP_STORIES_TSX,
       `
 import Button from "./App";
 
 export default {
-  component: Button
+  title: "Stories"
+}
+
+export const Primary = () => <Button primary label="Button" />;
+
+export const NotStory = (props) => <Button {...props} />;
+`
+    );
+
+    const extractedStories = extract(APP_STORIES_TSX);
+    expect(extractedStories).toMatchObject([
+      {
+        componentId: "App.stories.tsx:Primary",
+        info: {
+          kind: "story",
+          args: null,
+          associatedComponent: null,
+        },
+      },
+      {
+        componentId: "App.stories.tsx:NotStory",
+        info: {
+          kind: "component",
+          exported: true,
+        },
+      },
+    ]);
+  });
+
+  it("detects CSF2 stories (exported with title)", async () => {
+    memoryReader.updateFile(
+      APP_STORIES_TSX,
+      `
+import Button from "./App";
+
+export default {
+  title: "Stories"
 }
 
 const Template = (args) => <Button {...args} />;
@@ -380,26 +415,13 @@ Primary.args = {
               },
             ]),
           },
-          associatedComponent: {
-            componentId: "App.tsx:default",
-          },
+          associatedComponent: null,
         },
       },
     ]);
-    if (extractedStories[1]?.info.kind !== "story") {
-      throw new Error();
-    }
-    expect(
-      await extractedStories[1].info.associatedComponent.analyze()
-    ).toEqual({
-      propsType: objectType({
-        label: STRING_TYPE,
-      }),
-      types: {},
-    });
   });
 
-  it("detects CSF3 stories", async () => {
+  it("detects CSF3 stories (exported with component)", async () => {
     memoryReader.updateFile(
       APP_STORIES_TSX,
       `
@@ -452,19 +474,69 @@ export function NotStory() {}
         },
       },
     ]);
-    if (extractedStories[0]?.info.kind !== "story") {
+    const storyInfo = extractedStories[0]?.info;
+    if (storyInfo?.kind !== "story" || !storyInfo.associatedComponent) {
       throw new Error();
     }
-    expect(
-      await extractedStories[0].info.associatedComponent.analyze()
-    ).toEqual({
+    expect(await storyInfo.associatedComponent.analyze()).toEqual({
       propsType: objectType({
         label: STRING_TYPE,
       }),
       types: {},
     });
   });
 
+  it("detects CSF3 stories (exported with title)", async () => {
+    memoryReader.updateFile(
+      APP_STORIES_TSX,
+      `
+import Button from "./App";
+
+export default {
+  title: "Stories"
+}
+
+export const Example = {
+  args: {
+    label: "Hello, World!"
+  }
+}
+
+export const NoArgs = {}
+
+export function NotStory() {}
+`
+    );
+
+    const extractedStories = extract(APP_STORIES_TSX);
+    expect(extractedStories).toMatchObject([
+      {
+        componentId: "App.stories.tsx:Example",
+        info: {
+          kind: "story",
+          args: {
+            value: object([
+              {
+                kind: "key",
+                key: string("label"),
+                value: string("Hello, World!"),
+              },
+            ]),
+          },
+          associatedComponent: null,
+        },
+      },
+      {
+        componentId: "App.stories.tsx:NoArgs",
+        info: {
+          kind: "story",
+          args: null,
+          associatedComponent: null,
+        },
+      },
+    ]);
+  });
+
   function extract(absoluteFilePath: string) {
     return extractPreactComponents(
       logger,

framework-plugins/preact/src/extract-component.ts

@@ -4,7 +4,7 @@ import { parseSerializableValue } from "@previewjs/serializable-values";
 import {
   extractArgs,
   extractCsf3Stories,
-  extractDefaultComponent,
+  extractStoriesInfo,
   resolveComponentId,
 } from "@previewjs/storybook-helpers";
 import { TypeResolver, UNKNOWN_TYPE, helpers } from "@previewjs/type-analyzer";
@@ -60,7 +60,7 @@ export function extractPreactComponents(
     }
   }
 
-  const storiesDefaultComponent = extractDefaultComponent(sourceFile);
+  const storiesInfo = extractStoriesInfo(sourceFile);
   const components: AnalyzableComponent[] = [];
   const args = extractArgs(sourceFile);
   const nameToExportedName = helpers.extractExportedNames(sourceFile);
@@ -69,27 +69,23 @@ export function extractPreactComponents(
     node: ts.Node,
     name: string
   ): ComponentTypeInfo | null {
-    if (name === "default" && storiesDefaultComponent) {
+    if (name === "default" && storiesInfo) {
       return null;
     }
     const storyArgs = args[name];
     const isExported = name === "default" || !!nameToExportedName[name];
     const signature = extractComponentSignature(resolver.checker, node);
     if (
-      storiesDefaultComponent &&
+      storiesInfo &&
       isExported &&
       (storyArgs || signature?.parameters.length === 0)
     ) {
       const associatedComponent = extractStoryAssociatedComponent(
         logger,
         resolver,
         rootDirPath,
-        storiesDefaultComponent
+        storiesInfo.component
       );
-      if (!associatedComponent) {
-        // No detected associated component, give up.
-        return null;
-      }
       return {
         kind: "story",
         args: storyArgs
@@ -157,14 +153,14 @@ function extractStoryAssociatedComponent(
   logger: Logger,
   resolver: TypeResolver,
   rootDirPath: string,
-  component: ts.Expression
+  component: ts.Expression | null
 ) {
   const resolvedStoriesComponentId = resolveComponentId(
     rootDirPath,
     resolver.checker,
     component
   );
-  return resolvedStoriesComponentId
+  return component && resolvedStoriesComponentId
     ? {
         componentId: resolvedStoriesComponentId,
         analyze: async () => {