test: wait for stream close before writing to file

Wait for async operations on a file to finish before writing to it again. This fixes flakiness in parallel/test-readline-async-iterators-destroy. PR-URL: #30836Fixes: #30660 Reviewed-By: Luigi Pinca <[email protected]> Reviewed-By: Colin Ihrig <[email protected]> Reviewed-By: Rich Trott <[email protected]> Reviewed-By: Ben Noordhuis <[email protected]>

Author: addaleax

test/parallel/test-readline-async-iterators-destroy.js

@@ -2,6 +2,7 @@
 
 constcommon=require('../common');
 constfs=require('fs');
+const{ once }=require('events');
 const{ join }=require('path');
 constreadline=require('readline');
 constassert=require('assert');
@@ -42,6 +43,11 @@ async function testSimpleDestroy(){
 expectedLines.splice(1);
 
 assert.deepStrictEqual(iteratedLines,expectedLines);
+
+rli.close();
+readable.destroy();
+
+awaitonce(readable,'close');
 }
 }
 
@@ -72,6 +78,11 @@ async function testMutualDestroy(){
 }
 
 assert.deepStrictEqual(iteratedLines,expectedLines);
+
+rli.close();
+readable.destroy();
+
+awaitonce(readable,'close');
 }
 }