Method cachedRequest

packages/vite/src/module-runner/runner.ts:165–217

(
    url: string,
    mod: EvaluatedModuleNode,
    callstack: string[] = [],
    metadata?: SSRImportMetadata,
  )

  }

  private async cachedRequest(
    url: string,
    mod: EvaluatedModuleNode,
    callstack: string[] = [],
    metadata?: SSRImportMetadata,
  ): Promise<any> {
    const meta = mod.meta!
    const moduleId = meta.id

    const importee = callstack[callstack.length - 1]

    if (importee) mod.importers.add(importee)

    // fast path: already evaluated modules can't deadlock
    if (mod.evaluated && mod.promise) {
      return this.processImport(await mod.promise, meta, metadata)
    }

    if (mod.promise) {
      if (
        mod.exports &&
        (callstack.includes(moduleId) || this.isCircularRequest(mod, callstack))
      ) {
        return this.processImport(mod.exports, meta, metadata)
      }
      return this.processImport(await mod.promise, meta, metadata)
    }

    let debugTimer: any
    if (this.debug) {
      debugTimer = setTimeout(() => {
        const getStack = () =>
          `stack:\n${[...callstack, moduleId]
            .reverse()
            .map((p) => `  - ${p}`)
            .join('\n')}`

        this.debug!(
          `[module runner] module ${moduleId} takes over 2s to load.\n${getStack()}`,
        )
      }, 2000)
    }

    try {
      const promise = this.directRequest(url, mod, callstack)
      mod.promise = promise
      mod.evaluated = false
      return this.processImport(await promise, meta, metadata)
    } finally {
      mod.evaluated = true
      if (debugTimer) clearTimeout(debugTimer)
    }
  }

  private async cachedModule(
    url: string,