perf(vite-node): cache module fetch

vitest-dev · Jan 22, 2022 · 626a8dd · 626a8dd
1 parent 9cdc504
commit 626a8dd
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Showing 4 changed files with 60 additions and 24 deletions.
diff --git a/packages/vite-node/src/server.ts b/packages/vite-node/src/server.ts
@@ -1,12 +1,18 @@
 import type { TransformResult, ViteDevServer } from 'vite'
+import type { FetchResult } from '..'
 import { shouldExternalize } from './externalize'
 import type { ViteNodeResolveId, ViteNodeServerOptions } from './types'
 import { toFilePath, withInlineSourcemap } from './utils'
 
 export * from './externalize'
 
 export class ViteNodeServer {
-  promiseMap = new Map<string, Promise<TransformResult | null | undefined>>()
+  private fetchPromiseMap = new Map<string, Promise<FetchResult>>()
+  private transformPromiseMap = new Map<string, Promise<TransformResult | null | undefined>>()
+  private fetchCache = new Map<string, {
+    timestamp: number
+    result: FetchResult
+  }>()
 
   constructor(
     public server: ViteDevServer,
@@ -17,32 +23,37 @@ export class ViteNodeServer {
     return shouldExternalize(id, this.options.deps)
   }
 
-  async fetchModule(id: string) {
-    const externalize = await this.shouldExternalize(toFilePath(id, this.server.config.root))
-    if (externalize)
-      return { externalize }
-    const r = await this.transformRequest(id)
-    return { code: r?.code }
-  }
-
   async resolveId(id: string, importer?: string): Promise<ViteNodeResolveId | null> {
     return this.server.pluginContainer.resolveId(id, importer, { ssr: true })
   }
 
+  async fetchModule(id: string): Promise<FetchResult> {
+    // reuse transform for concurrent requests
+    if (!this.fetchPromiseMap.has(id)) {
+      this.fetchPromiseMap.set(id,
+        this._fetchModule(id)
+          .finally(() => {
+            this.fetchPromiseMap.delete(id)
+          }),
+      )
+    }
+    return this.fetchPromiseMap.get(id)!
+  }
+
   async transformRequest(id: string) {
     // reuse transform for concurrent requests
-    if (!this.promiseMap.has(id)) {
-      this.promiseMap.set(id,
+    if (!this.transformPromiseMap.has(id)) {
+      this.transformPromiseMap.set(id,
         this._transformRequest(id)
           .finally(() => {
-            this.promiseMap.delete(id)
+            this.transformPromiseMap.delete(id)
           }),
       )
     }
-    return this.promiseMap.get(id)
+    return this.transformPromiseMap.get(id)!
   }
 
-  private getTransformMode(id: string) {
+  getTransformMode(id: string) {
     const withoutQuery = id.split('?')[0]
 
     if (this.options.transformMode?.web?.some(r => withoutQuery.match(r)))
@@ -55,11 +66,37 @@ export class ViteNodeServer {
     return 'web'
   }
 
+  private async _fetchModule(id: string): Promise<FetchResult> {
+    let result: FetchResult
+
+    const timestamp = this.server.moduleGraph.getModuleById(id)?.lastHMRTimestamp
+    const cache = this.fetchCache.get(id)
+    if (timestamp && cache && cache.timestamp >= timestamp)
+      return cache.result
+
+    const externalize = await this.shouldExternalize(toFilePath(id, this.server.config.root))
+    if (externalize) {
+      result = { externalize }
+    }
+    else {
+      const r = await this._transformRequest(id)
+      result = { code: r?.code }
+    }
+
+    if (timestamp) {
+      this.fetchCache.set(id, {
+        timestamp,
+        result,
+      })
+    }
+
+    return result
+  }
+
   private async _transformRequest(id: string) {
     let result: TransformResult | null = null
 
-    const mode = this.getTransformMode(id)
-    if (mode === 'web') {
+    if (this.getTransformMode(id) === 'web') {
       // for components like Vue, we want to use the client side
       // plugins but then covert the code to be consumed by the server
       result = await this.server.transformRequest(id)
@@ -73,10 +110,6 @@ export class ViteNodeServer {
     if (this.options.sourcemap !== false && result && !id.includes('node_modules'))
       withInlineSourcemap(result)
 
-    // if (result?.map && process.env.NODE_V8_COVERAGE)
-    //   visitedFilesMap.set(toFilePath(id, config.root), result.map as any)
-
     return result
   }
 }
-
diff --git a/packages/vite-node/src/types.ts b/packages/vite-node/src/types.ts
@@ -8,7 +8,12 @@ export interface DepsHandlingOptions {
   fallbackCJS?: boolean
 }
 
-export type FetchFunction = (id: string) => Promise<{ code?: string; externalize?: string }>
+export interface FetchResult {
+  code?: string
+  externalize?: string
+}
+
+export type FetchFunction = (id: string) => Promise<FetchResult>
 export type ResolveIdFunction = (id: string, importer?: string) => Promise<ViteNodeResolveId | null>
 
 export interface ModuleCache {

diff --git a/packages/vite-node/src/utils.ts b/packages/vite-node/src/utils.ts
@@ -43,7 +43,6 @@ export function toFilePath(id: string, root: string): string {
     : absolute
 }
 
-
 let SOURCEMAPPING_URL = 'sourceMa'
 SOURCEMAPPING_URL += 'ppingURL'
 

diff --git a/packages/vitest/src/types/worker.ts b/packages/vitest/src/types/worker.ts
@@ -1,5 +1,5 @@
 import type { MessagePort } from 'worker_threads'
-import type { ViteNodeResolveId } from 'vite-node'
+import type { FetchFunction, ViteNodeResolveId } from 'vite-node'
 import type { RawSourceMap } from '../types'
 import type { ResolvedConfig } from './config'
 import type { File, TaskResultPack } from './tasks'
@@ -13,7 +13,6 @@ export interface WorkerContext {
   invalidates?: string[]
 }
 
-export type FetchFunction = (id: string) => Promise<{ code?: string; externalize?: string }>
 export type ResolveIdFunction = (id: string, importer?: string) => Promise<ViteNodeResolveId | null>
 
 export interface WorkerRPC {