perf(moduleGraph): resolve dep urls in parallel

packages/vite/src/node/server/moduleGraph.ts

@@ -148,17 +148,33 @@ export class ModuleGraph {
   ): Promise<Set<ModuleNode> | undefined> {
     mod.isSelfAccepting = isSelfAccepting
     const prevImports = mod.importedModules
-    const nextImports = (mod.importedModules = new Set())
     let noLongerImported: Set<ModuleNode> | undefined
+
+    let resolvePromises = []
+    let resolveResults = new Array(importedModules.size)
+    let index = 0
     // update import graph
     for (const imported of importedModules) {
-      const dep =
-        typeof imported === 'string'
-          ? await this.ensureEntryFromUrl(imported, ssr)
-          : imported
-      dep.importers.add(mod)
-      nextImports.add(dep)
+      const nextIndex = index++
+      if (typeof imported === 'string') {
+        resolvePromises.push(
+          this.ensureEntryFromUrl(imported, ssr).then((dep) => {
+            dep.importers.add(mod)
+            resolveResults[nextIndex] = dep
+          }),
+        )
+      } else {
+        imported.importers.add(mod)
+        resolveResults[nextIndex] = imported
+      }
+    }
+
+    if (resolvePromises.length) {
+      await Promise.all(resolvePromises)
     }
+
+    const nextImports = (mod.importedModules = new Set(resolveResults))
+
     // remove the importer from deps that were imported but no longer are.
     prevImports.forEach((dep) => {
       if (!nextImports.has(dep)) {
@@ -169,15 +185,30 @@ export class ModuleGraph {
         }
       }
     })
+
     // update accepted hmr deps
-    const deps = (mod.acceptedHmrDeps = new Set())
+    resolvePromises = []
+    resolveResults = new Array(acceptedModules.size)
+    index = 0
     for (const accepted of acceptedModules) {
-      const dep =
-        typeof accepted === 'string'
-          ? await this.ensureEntryFromUrl(accepted, ssr)
-          : accepted
-      deps.add(dep)
+      const nextIndex = index++
+      if (typeof accepted === 'string') {
+        resolvePromises.push(
+          this.ensureEntryFromUrl(accepted, ssr).then((dep) => {
+            resolveResults[nextIndex] = dep
+          }),
+        )
+      } else {
+        resolveResults[nextIndex] = accepted
+      }
+    }
+
+    if (resolvePromises.length) {
+      await Promise.all(resolvePromises)
     }
+
+    mod.acceptedHmrDeps = new Set(resolveResults)
+
     // update accepted hmr exports
     mod.acceptedHmrExports = acceptedExports
     mod.importedBindings = importedBindings