feat: clear console on rebuild start

Author: sxzz

dts.snapshot.json

@@ -102,7 +102,7 @@
     "Format": "type Format = ModuleFormat",
     "globalLogger": "Logger",
     "InlineConfig": "interface InlineConfig extends UserConfig {\n config?: boolean | string\n configLoader?: 'auto' | 'native' | 'unrun'\n filter?: RegExp | Arrayable<string>\n}",
-    "Logger": "interface Logger {\n level: LogLevel\n info: (...args: any[]) => void\n warn: (...args: any[]) => void\n warnOnce: (...args: any[]) => void\n error: (...args: any[]) => void\n success: (...args: any[]) => void\n}",
+    "Logger": "interface Logger {\n level: LogLevel\n info: (...args: any[]) => void\n warn: (...args: any[]) => void\n warnOnce: (...args: any[]) => void\n error: (...args: any[]) => void\n success: (...args: any[]) => void\n clearScreen: (_: LogType) => void\n}",
     "LogLevel": "type LogLevel = LogType | 'silent'",
     "LogType": "type LogType = 'error' | 'warn' | 'info'",
     "MarkPartial": "type MarkPartial<T, K$1 extends keyof T> = Omit<Required<T>, K$1> & Partial<Pick<T, K$1>>",

src/build.ts

@@ -211,10 +211,8 @@ async function buildSingle(
         }
 
         case 'BUNDLE_START': {
-          if (changedFile.length > 0) {
-            if (logger.level === 'info') {
-              console.info('')
-            }
+          if (changedFile.length) {
+            logger.clearScreen('info')
             logger.info(
               `Found ${bold(changedFile.join(', '))} changed, rebuilding...`,
             )

src/utils/logger.ts

@@ -1,4 +1,5 @@
 import process from 'node:process'
+import readline from 'node:readline'
 import { bgRed, bgYellow, blue, green, rgb, yellow, type Ansis } from 'ansis'
 import { noop } from './general.ts'
 import type { InternalModuleFormat } from 'rolldown'
@@ -7,6 +8,7 @@ export type LogType = 'error' | 'warn' | 'info'
 export type LogLevel = LogType | 'silent'
 
 export interface LoggerOptions {
+  allowClearScreen?: boolean
   customLogger?: Logger
   console?: Console
   failOnWarn?: boolean
@@ -26,12 +28,21 @@ export interface Logger {
   warnOnce: (...args: any[]) => void
   error: (...args: any[]) => void
   success: (...args: any[]) => void
+  clearScreen: (type: LogType) => void
 }
 
 function format(msgs: any[]) {
   return msgs.filter((arg) => arg !== undefined && arg !== false).join(' ')
 }
 
+function clearScreen() {
+  const repeatCount = process.stdout.rows - 2
+  const blank = repeatCount > 0 ? '\n'.repeat(repeatCount) : ''
+  console.info(blank)
+  readline.cursorTo(process.stdout, 0, 0)
+  readline.clearScreenDown(process.stdout)
+}
+
 const warnedMessages = new Set<string>()
 
 export function createLogger(
@@ -40,6 +51,7 @@ export function createLogger(
     customLogger,
     console = globalThis.console,
     failOnWarn = false,
+    allowClearScreen = true,
   }: LoggerOptions = {},
 ): Logger {
   if (customLogger) {
@@ -54,6 +66,10 @@ export function createLogger(
     console[method](msg)
   }
 
+  const canClearScreen =
+    allowClearScreen && process.stdout.isTTY && !process.env.CI
+  const clear = canClearScreen ? clearScreen : () => {}
+
   const logger: Logger = {
     level,
 
@@ -92,6 +108,12 @@ export function createLogger(
     success(...msgs: any[]): void {
       output('info', `${green`✔`} ${format(msgs)}`)
     },
+
+    clearScreen(type) {
+      if (LogLevels[logger.level] >= LogLevels[type]) {
+        clear()
+      }
+    },
   }
   return logger
 }