feat(optimizer): log when dependency scanning or bundling takes over 1s (#21797)

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: o-m12a

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

@@ -644,6 +644,12 @@ export function runOptimizeDeps(
 
   const start = performance.now()
 
+  const bundleTimer = setTimeout(() => {
+    environment.logger.info('[optimizer] bundling dependencies...', {
+      timestamp: true,
+    })
+  }, 1000)
+
   const preparedRun = prepareRolldownOptimizerRun(
     environment,
     depsInfo,
@@ -653,6 +659,7 @@ export function runOptimizeDeps(
 
   const runResult = preparedRun.then(({ context, idToExports }) => {
     if (!context || optimizerContext.cancelled) {
+      clearTimeout(bundleTimer)
       return cancelledResult
     }
 
@@ -712,6 +719,8 @@ export function runOptimizeDeps(
           }
         }
 
+        clearTimeout(bundleTimer)
+
         debug?.(
           `Dependencies bundled in ${(performance.now() - start).toFixed(2)}ms`,
         )
@@ -720,6 +729,7 @@ export function runOptimizeDeps(
       })
 
       .catch((e) => {
+        clearTimeout(bundleTimer)
         if (e.errors && e.message.includes('The build was canceled')) {
           // an error happens when cancelling, but this is expected so
           // return an empty result instead

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

@@ -200,6 +200,12 @@ export function createDepsOptimizer(
             try {
               debug?.(colors.green(`scanning for dependencies...`))
 
+              const scanTimer = setTimeout(() => {
+                logger.info('[optimizer] scanning dependencies...', {
+                  timestamp: true,
+                })
+              }, 1000)
+
               let deps: Record<string, string>
               try {
                 discover = discoverProjectDependencies(
@@ -216,6 +222,8 @@ export function createDepsOptimizer(
                   ),
                 )
                 return
+              } finally {
+                clearTimeout(scanTimer)
               }
 
               const manuallyIncluded = Object.keys(manuallyIncludedDepsInfo)