Core: Improve internal types

code/lib/core-common/src/utils/validate-config.ts

@@ -6,7 +6,9 @@ const renderers = ['html', 'preact', 'react', 'server', 'svelte', 'vue', 'vue3',
 
 const rendererNames = [...renderers, ...renderers.map((renderer) => `@storybook/${renderer}`)];
 
-export function validateFrameworkName(frameworkName: string | undefined) {
+export function validateFrameworkName(
+  frameworkName: string | undefined
+): asserts frameworkName is string {
   const automigrateMessage = `Please run 'npx storybook@next automigrate' to automatically fix your config.
 
   See the migration guide for more information: 

code/lib/core-server/src/build-dev.ts

@@ -31,13 +31,15 @@ export async function buildDevStandalone(
   options: CLIOptions & LoadOptions & BuilderOptions
 ): Promise<{ port: number; address: string; networkAddress: string }> {
   const { packageJson, versionUpdates } = options;
-  const { version } = packageJson;
-  invariant(version !== undefined, 'Expected package.json version to be defined.');
+  invariant(
+    packageJson.version !== undefined,
+    `Expected package.json#version to be defined in the "${packageJson.name}" package}`
+  );
   // updateInfo are cached, so this is typically pretty fast
   const [port, versionCheck] = await Promise.all([
     getServerPort(options.port),
     versionUpdates
-      ? updateCheck(version)
+      ? updateCheck(packageJson.version)
       : Promise.resolve({ success: false, cached: false, data: {}, time: Date.now() }),
   ]);
 
@@ -64,10 +66,9 @@ export async function buildDevStandalone(
 
   const config = await loadMainConfig(options);
   const { framework } = config;
-  invariant(framework, 'framework is required in Storybook v7');
   const corePresets = [];
 
-  const frameworkName = typeof framework === 'string' ? framework : framework.name;
+  const frameworkName = typeof framework === 'string' ? framework : framework?.name;
   validateFrameworkName(frameworkName);
 
   corePresets.push(join(frameworkName, 'preset'));
@@ -84,7 +85,8 @@ export async function buildDevStandalone(
   });
 
   const { renderer, builder, disableTelemetry } = await presets.apply<CoreConfig>('core', {});
-  invariant(builder, 'no builder configured!');
+
+  invariant(builder, 'No builder configured in core.builder');
 
   if (!options.disableTelemetry && !disableTelemetry) {
     if (versionCheck.success && !versionCheck.cached) {
@@ -98,9 +100,8 @@ export async function buildDevStandalone(
     getManagerBuilder(),
   ]);
 
-  const resolvedRenderer = renderer
-    ? resolveAddonName(options.configDir, renderer, options)
-    : undefined;
+  const resolvedRenderer = renderer && resolveAddonName(options.configDir, renderer, options);
+
   // Load second pass: all presets are applied in order
   presets = await loadAllPresets({
     corePresets: [
@@ -128,10 +129,10 @@ export async function buildDevStandalone(
     fullOptions
   );
 
-  const previewTotalTime = previewResult && previewResult.totalTime;
-  const managerTotalTime = managerResult ? managerResult.totalTime : undefined;
-  const previewStats = previewResult && previewResult.stats;
-  const managerStats = managerResult && managerResult.stats;
+  const previewTotalTime = previewResult?.totalTime;
+  const managerTotalTime = managerResult?.totalTime;
+  const previewStats = previewResult?.stats;
+  const managerStats = managerResult?.stats;
 
   if (options.webpackStatsJson) {
     const target = options.webpackStatsJson === true ? options.outputDir : options.webpackStatsJson;
@@ -162,7 +163,7 @@ export async function buildDevStandalone(
     if (!options.quiet) {
       outputStartupInformation({
         updateInfo: versionCheck,
-        version,
+        version: packageJson.version,
         name,
         address,
         networkAddress,

code/lib/core-server/src/build-static.ts

@@ -173,21 +173,20 @@ export async function buildStaticStandalone(options: BuildStaticStandaloneOption
       storyStoreV7: !!features?.storyStoreV7,
     });
 
-    const initializedStoryIndexGeneratorPromise = generator.initialize().then(() => generator);
+    initializedStoryIndexGenerator = generator.initialize().then(() => generator);
     effects.push(
       extractStoriesJson(
         join(options.outputDir, 'stories.json'),
-        initializedStoryIndexGeneratorPromise,
+        initializedStoryIndexGenerator as Promise<StoryIndexGenerator>,
         convertToIndexV3
       )
     );
     effects.push(
       extractStoriesJson(
         join(options.outputDir, 'index.json'),
-        initializedStoryIndexGeneratorPromise
+        initializedStoryIndexGenerator as Promise<StoryIndexGenerator>
       )
     );
-    initializedStoryIndexGenerator = initializedStoryIndexGeneratorPromise;
   }
 
   if (!core?.disableProjectJson) {

code/lib/core-server/src/utils/get-builders.ts

@@ -10,15 +10,10 @@ export async function getPreviewBuilder(
   builderName: string,
   configDir: string
 ): Promise<Builder<unknown>> {
-  let builderPackage: string;
-  if (builderName) {
-    builderPackage = require.resolve(
-      ['webpack5'].includes(builderName) ? `@storybook/builder-${builderName}` : builderName,
-      { paths: [configDir] }
-    );
-  } else {
-    throw new Error('no builder configured!');
-  }
+  const builderPackage = require.resolve(
+    ['webpack5'].includes(builderName) ? `@storybook/builder-${builderName}` : builderName,
+    { paths: [configDir] }
+  );
   const previewBuilder = await import(pathToFileURL(builderPackage).href);
   return previewBuilder;
 }

code/lib/core-server/src/utils/getStoryIndexGenerator.ts

@@ -14,40 +14,40 @@ export async function getStoryIndexGenerator(
   },
   options: Options,
   serverChannel: ServerChannel
-) {
-  if (features?.buildStoriesJson || features?.storyStoreV7) {
-    const workingDir = process.cwd();
-    const directories = {
-      configDir: options.configDir,
-      workingDir,
-    };
-    const stories = options.presets.apply('stories');
-    const deprecatedStoryIndexers = options.presets.apply('storyIndexers', []);
-    const indexers = options.presets.apply('indexers', []);
-    const docsOptions = options.presets.apply<DocsOptions>('docs', {});
-    const normalizedStories = normalizeStories(await stories, directories);
+): Promise<StoryIndexGenerator | undefined> {
+  if (!features?.buildStoriesJson && !features?.storyStoreV7) {
+    return undefined;
+  }
+  const workingDir = process.cwd();
+  const directories = {
+    configDir: options.configDir,
+    workingDir,
+  };
+  const stories = options.presets.apply('stories');
+  const deprecatedStoryIndexers = options.presets.apply('storyIndexers', []);
+  const indexers = options.presets.apply('indexers', []);
+  const docsOptions = options.presets.apply<DocsOptions>('docs', {});
+  const normalizedStories = normalizeStories(await stories, directories);
 
-    const generator = new StoryIndexGenerator(normalizedStories, {
-      ...directories,
-      storyIndexers: await deprecatedStoryIndexers,
-      indexers: await indexers,
-      docs: await docsOptions,
-      workingDir,
-      storiesV2Compatibility: !features?.storyStoreV7,
-      storyStoreV7: features.storyStoreV7 ?? false,
-    });
+  const generator = new StoryIndexGenerator(normalizedStories, {
+    ...directories,
+    storyIndexers: await deprecatedStoryIndexers,
+    indexers: await indexers,
+    docs: await docsOptions,
+    workingDir,
+    storiesV2Compatibility: !features?.storyStoreV7,
+    storyStoreV7: features.storyStoreV7 ?? false,
+  });
 
-    const initializedStoryIndexGenerator = generator.initialize().then(() => generator);
+  const initializedStoryIndexGenerator = generator.initialize().then(() => generator);
 
-    useStoriesJson({
-      router,
-      initializedStoryIndexGenerator,
-      normalizedStories,
-      serverChannel,
-      workingDir,
-    });
+  useStoriesJson({
+    router,
+    initializedStoryIndexGenerator,
+    normalizedStories,
+    serverChannel,
+    workingDir,
+  });
 
-    return initializedStoryIndexGenerator;
-  }
-  return Promise.resolve(undefined);
+  return initializedStoryIndexGenerator;
 }

code/lib/core-server/src/utils/server-statics.ts

@@ -12,7 +12,8 @@ import { dedent } from 'ts-dedent';
 import { defaultStaticDirs } from './constants';
 
 export async function useStatics(router: any, options: Options) {
-  const staticDirs = await options.presets.apply<StorybookConfig['staticDirs']>('staticDirs');
+  const staticDirs =
+    (await options.presets.apply<StorybookConfig['staticDirs']>('staticDirs')) ?? [];
   const faviconPath = await options.presets.apply<string>('favicon');
 
   if (options.staticDir && !isEqual(staticDirs, defaultStaticDirs)) {
@@ -26,7 +27,7 @@ export async function useStatics(router: any, options: Options) {
   }
 
   const statics = [
-    ...(staticDirs ?? []).map((dir) => (typeof dir === 'string' ? dir : `${dir.from}:${dir.to}`)),
+    ...staticDirs.map((dir) => (typeof dir === 'string' ? dir : `${dir.from}:${dir.to}`)),
     ...(options.staticDir || []),
   ];
 

code/lib/core-server/src/withTelemetry.ts

@@ -4,6 +4,7 @@ import { loadAllPresets, cache } from '@storybook/core-common';
 import { telemetry, getPrecedingUpgrade, oneWayHash } from '@storybook/telemetry';
 import type { EventType } from '@storybook/telemetry';
 import { logger } from '@storybook/node-logger';
+import invariant from 'tiny-invariant';
 
 type TelemetryOptions = {
   cliOptions: CLIOptions;
@@ -66,7 +67,7 @@ async function getErrorLevel({
 }
 
 export async function sendTelemetryError(
-  error: Error,
+  error: unknown,
   eventType: EventType,
   options: TelemetryOptions
 ) {
@@ -80,13 +81,17 @@ export async function sendTelemetryError(
     if (errorLevel !== 'none') {
       const precedingUpgrade = await getPrecedingUpgrade();
 
+      invariant(
+        error instanceof Error,
+        'The error passed to sendTelemetryError was not an Error, please only send Errors'
+      );
       await telemetry(
         'error',
         {
           eventType,
           precedingUpgrade,
           error: errorLevel === 'full' ? error : undefined,
-          errorHash: oneWayHash(error.message || ''),
+          errorHash: oneWayHash(error.message),
         },
         {
           immediate: true,
@@ -132,8 +137,8 @@ export async function withTelemetry<T>(
     }
 
     const { printError = logger.error } = options;
-    printError(error instanceof Error ? error.message : String(error));
-    if (error instanceof Error) await sendTelemetryError(error, eventType, options);
+    printError(error);
+    await sendTelemetryError(error, eventType, options);
 
     throw error;
   } finally {

code/lib/node-logger/src/index.ts

@@ -25,7 +25,8 @@ export const logger = {
   plain: (message: string): void => console.log(message),
   line: (count = 1): void => console.log(`${Array(count - 1).fill('\n')}`),
   warn: (message: string): void => npmLog.warn('', message),
-  error: (message: string): void => npmLog.error('', message),
+  // npmLog supports anything we log, it will just stringify it
+  error: (message: unknown): void => npmLog.error('', message as string),
   trace: ({ message, time }: { message: string; time: [number, number] }): void =>
     npmLog.info('', `${message} (${colors.purple(prettyTime(time))})`),
   setLevel: (level = 'info'): void => {