fix: syncMode - default: use append strategy when using dev server, overwrite strategy when using build.

Author: xiaweiss

src/core/context.ts

@@ -43,7 +43,10 @@ export class Context {
     this.options = resolveOptions(rawOptions, this.root)
     this.sourcemap = rawOptions.sourcemap ?? true
     this.generateDeclaration = throttle(500, this._generateDeclaration.bind(this), { noLeading: false })
-    this._removeUnused = this.options.syncMode === 'overwrite'
+
+    // syncMode - `default`: use `append` strategy when using dev server, `overwrite` strategy when using build.
+    const syncMode = this.options.syncMode === 'default' ? (process.env.NODE_ENV === 'development' ? 'append' : 'overwrite') : this.options.syncMode
+    this._removeUnused = syncMode === 'overwrite'
 
     if (this.options.dumpComponentsInfo) {
       const dumpComponentsInfo = this.options.dumpComponentsInfo === true
@@ -80,7 +83,6 @@ export class Context {
       return
 
     this._server = server
-    this._removeUnused = this.options.syncMode !== 'append'
     this.setupWatcher(server.watcher)
   }