fix: Improved debounce to prevent multiple extension reloads on conse…

…cutive file changes (#2385) Co-authored-by: Federico Brigante <me@fregante.com>
mozilla · Mar 24, 2022 · 6c53a01 · 6c53a01
1 parent 81083df
commit 6c53a01
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Showing 2 changed files with 6 additions and 2 deletions.
diff --git a/src/watcher.js b/src/watcher.js
@@ -36,7 +36,7 @@ export default function onSourceChange(
     artifactsDir,
     onChange,
     shouldWatchFile,
-    debounceTime = 1000,
+    debounceTime = 500,
   }: OnSourceChangeParams
 ): Watchpack {
   // When running on Windows, transform the ignored paths and globs
@@ -51,7 +51,8 @@ export default function onSourceChange(
     new Watchpack({ignored}) :
     new Watchpack();
 
-  const executeImmediately = true;
+  // Allow multiple files to be changed before reloading the extension
+  const executeImmediately = false;
   onChange = debounce(onChange, debounceTime, executeImmediately);
 
   watcher.on('change', (filePath) => {

diff --git a/tests/unit/test.watcher.js b/tests/unit/test.watcher.js
@@ -93,6 +93,7 @@ describe('watcher', () => {
   );
 
   it('watches for changes in the sourceDir', async () => {
+    const defaultDebounce = 500;
     const {
       onChange,
       watchedFilePath,
@@ -102,6 +103,8 @@ describe('watcher', () => {
       touchedFile: 'foo.txt',
     });
 
+    await new Promise((resolve) => setTimeout(resolve, defaultDebounce + 50));
+
     sinon.assert.calledOnce(onChange);
     assert.equal(watchedDirPath, tmpDirPath);
     assert.isUndefined(watchedFilePath);