fix(watcher): debounce event handling

Author: pi0

package.json

@@ -46,22 +46,23 @@
     "ofetch": "^1.3.3",
     "omark": "^0.1.0",
     "pathe": "^1.1.2",
+    "perfect-debounce": "^1.0.0",
     "pkg-types": "^1.0.3",
     "scule": "^1.3.0",
     "untyped": "^1.4.2"
   },
   "devDependencies": {
     "@types/node": "^20.11.20",
     "@vitest/coverage-v8": "^1.3.1",
+    "automd": "link:.",
     "changelogen": "^0.5.5",
     "eslint": "^8.57.0",
     "eslint-config-unjs": "^0.2.1",
     "jiti": "^1.21.0",
     "prettier": "^3.2.5",
     "typescript": "^5.3.3",
     "unbuild": "^2.0.0",
-    "vitest": "^1.3.1",
-    "automd": "link:."
+    "vitest": "^1.3.1"
   },
   "packageManager": "pnpm@8.15.3"
 }

pnpm-lock.yaml

@@ -2,6 +2,7 @@ import { existsSync, promises as fsp } from "node:fs";
 import { resolve, relative } from "pathe";
 import type { SubscribeCallback } from "@parcel/watcher";
 import { pathToFileURL } from "mlly";
+import { debounce } from "perfect-debounce";
 import type { Config, ResolvedConfig } from "./config";
 import { type TransformResult, transform } from "./transform";
 import { loadConfig } from "./config";
@@ -108,7 +109,7 @@ async function _watch(
 ) {
   const watcher = await import("@parcel/watcher");
 
-  const watchCb: SubscribeCallback = async (_err, events) => {
+  const watchCb: SubscribeCallback = debounce(async (_err, events) => {
     const filesToUpdate = events
       .map((e) => relative(config.dir, e.path))
       .filter((p) => inputFiles.includes(p));
@@ -120,7 +121,7 @@ async function _watch(
     if (config.onWatch) {
       config.onWatch({ results, time });
     }
-  };
+  });
 
   const subscription = await watcher.subscribe(config.dir, watchCb, {
     ignore: config.ignore,