feat: single cancellable scan

packages/vite/src/node/optimizer/index.ts

@@ -239,7 +239,7 @@ export async function optimizeDeps(
     return cachedMetadata
   }
 
-  const deps = await discoverProjectDependencies(config)
+  const deps = await (await discoverProjectDependencies(config)).depsPromise
 
   const depsString = depsLogString(Object.keys(deps))
   log(colors.green(`Optimizing dependencies:\n  ${depsString}`))
@@ -382,24 +382,31 @@ export function loadCachedDepOptimizationMetadata(
  */
 export async function discoverProjectDependencies(
   config: ResolvedConfig,
-): Promise<Record<string, string>> {
-  const { deps, missing } = await scanImports(config)
-
-  const missingIds = Object.keys(missing)
-  if (missingIds.length) {
-    throw new Error(
-      `The following dependencies are imported but could not be resolved:\n\n  ${missingIds
-        .map(
-          (id) =>
-            `${colors.cyan(id)} ${colors.white(
-              colors.dim(`(imported by ${missing[id]})`),
-            )}`,
+): Promise<{
+  cancel: () => void
+  depsPromise: Promise<Record<string, string>>
+}> {
+  const { cancel, resultsPromise } = await scanImports(config)
+  return {
+    cancel,
+    depsPromise: resultsPromise.then(({ deps, missing }) => {
+      const missingIds = Object.keys(missing)
+      if (missingIds.length) {
+        throw new Error(
+          `The following dependencies are imported but could not be resolved:\n\n  ${missingIds
+            .map(
+              (id) =>
+                `${colors.cyan(id)} ${colors.white(
+                  colors.dim(`(imported by ${missing[id]})`),
+                )}`,
+            )
+            .join(`\n  `)}\n\nAre they installed?`,
         )
-        .join(`\n  `)}\n\nAre they installed?`,
-    )
-  }
+      }
 
-  return deps
+      return deps
+    }),
+  }
 }
 
 export function toDiscoveredDependencies(
@@ -679,7 +686,7 @@ export async function findKnownImports(
   config: ResolvedConfig,
   ssr: boolean,
 ): Promise<string[]> {
-  const deps = (await scanImports(config)).deps
+  const { deps } = await (await scanImports(config)).resultsPromise
   await addManuallyIncludedOptimizeDeps(deps, config, ssr)
   return Object.keys(deps)
 }

packages/vite/src/node/optimizer/optimizer.ts

@@ -161,18 +161,20 @@ async function createDepsOptimizer(
   let firstRunCalled = !!cachedMetadata
 
   let postScanOptimizationResult: Promise<DepOptimizationResult> | undefined
-  let discoverProjectDependenciesPromise:
-    | Promise<Record<string, string>>
-    | undefined
+  let discover: {
+    cancel: () => void
+    depsPromise: Promise<Record<string, string>>
+  }
 
   let optimizingNewDeps: Promise<DepOptimizationResult> | undefined
   async function close() {
     closed = true
-    await discoverProjectDependenciesPromise?.catch(() => {
-      /* ignore error for scanner because it's not important */
-    })
-    await postScanOptimizationResult
-    await optimizingNewDeps
+    discover?.cancel()
+    await Promise.allSettled([
+      discover?.depsPromise ?? Promise.resolve(),
+      postScanOptimizationResult,
+      optimizingNewDeps,
+    ])
   }
 
   if (!cachedMetadata) {
@@ -208,9 +210,8 @@ async function createDepsOptimizer(
         try {
           debug(colors.green(`scanning for dependencies...`))
 
-          discoverProjectDependenciesPromise =
-            discoverProjectDependencies(config)
-          const deps = await discoverProjectDependenciesPromise
+          discover = await discoverProjectDependencies(config)
+          const deps = await discover.depsPromise
 
           debug(
             colors.green(

packages/vite/src/node/optimizer/scan.ts

@@ -48,8 +48,12 @@ export const importsRE =
   /(?<!\/\/.*)(?<=^|;|\*\/)\s*import(?!\s+type)(?:[\w*{}\n\r\t, ]+from)?\s*("[^"]+"|'[^']+')\s*(?=$|;|\/\/|\/\*)/gm
 
 export async function scanImports(config: ResolvedConfig): Promise<{
-  deps: Record<string, string>
-  missing: Record<string, string>
+  cancel: () => void
+  resultsPromise: Promise<{
+    deps: Record<string, string>
+    missing: Record<string, string>
+    cancelled?: boolean
+  }>
 }> {
   // Only used to scan non-ssr code
 
@@ -93,7 +97,10 @@ export async function scanImports(config: ResolvedConfig): Promise<{
         ),
       )
     }
-    return { deps: {}, missing: {} }
+    return {
+      cancel: () => {},
+      resultsPromise: Promise.resolve({ deps: {}, missing: {} }),
+    }
   } else {
     debug(`Crawling dependencies using entries:\n  ${entries.join('\n  ')}`)
   }
@@ -102,31 +109,43 @@ export async function scanImports(config: ResolvedConfig): Promise<{
   const missing: Record<string, string> = {}
   const container = await createPluginContainer(config)
   const plugin = esbuildScanPlugin(config, container, deps, missing, entries)
-
+  const { cancel, plugin: cancelPlugin } = esbuildCancelPlugin()
   const { plugins = [], ...esbuildOptions } =
     config.optimizeDeps?.esbuildOptions ?? {}
 
-  await Promise.all(
-    entries.map((entry) =>
-      build({
-        absWorkingDir: process.cwd(),
-        write: false,
-        entryPoints: [entry],
-        bundle: true,
-        format: 'esm',
-        logLevel: 'error',
-        plugins: [...plugins, plugin],
-        ...esbuildOptions,
-      }),
-    ),
-  )
-
-  debug(`Scan completed in ${(performance.now() - start).toFixed(2)}ms:`, deps)
-
+  const resultsPromise = build({
+    absWorkingDir: process.cwd(),
+    write: false,
+    stdin: {
+      contents: entries.map((e) => `import '${e}'`).join('\n'),
+      loader: 'js',
+    },
+    bundle: true,
+    format: 'esm',
+    logLevel: 'error',
+    plugins: [...plugins, plugin, cancelPlugin],
+    ...esbuildOptions,
+  })
+    .then(() => ({
+      // Ensure a fixed order so hashes are stable and improve logs
+      deps: orderedDependencies(deps),
+      missing,
+    }))
+    .catch((e) => {
+      if (e.message === 'vite:cancel') {
+        return { deps: {}, missing: {}, cancelled: true }
+      }
+      throw e
+    })
+    .finally(() => {
+      debug(
+        `Scan completed in ${(performance.now() - start).toFixed(2)}ms:`,
+        deps,
+      )
+    })
   return {
-    // Ensure a fixed order so hashes are stable and improve logs
-    deps: orderedDependencies(deps),
-    missing,
+    cancel,
+    resultsPromise,
   }
 }
 
@@ -519,6 +538,26 @@ function esbuildScanPlugin(
   }
 }
 
+function esbuildCancelPlugin(): { plugin: Plugin; cancel: () => void } {
+  let cancelled = false
+  const plugin: Plugin = {
+    name: 'vite:cancel',
+    setup(build) {
+      // external urls
+      build.onResolve({ filter: /.*/ }, () => {
+        if (cancelled) {
+          throw new Error('vite:cancel')
+        }
+        return null
+      })
+    },
+  }
+  const cancel = () => {
+    cancelled = true
+  }
+  return { plugin, cancel }
+}
+
 /**
  * when using TS + (Vue + `<script setup>`) or Svelte, imports may seem
  * unused to esbuild and dropped in the build output, which prevents