stream: allow empty string as source of pipeline

Fixes: #38721 PR-URL: #38723 Reviewed-By: Ruben Bridgewater <[email protected]> Reviewed-By: Antoine du Hamel <[email protected]> Reviewed-By: Robert Nagy <[email protected]> Reviewed-By: James M Snell <[email protected]> Reviewed-By: Luigi Pinca <[email protected]> Reviewed-By: Zijian Liu <[email protected]> Reviewed-By: Darshan Sen <[email protected]>

Author: Ayase-252

lib/internal/streams/utils.js

@@ -20,7 +20,7 @@ function isStream(obj){
 }
 
 functionisIterable(obj,isAsync){
-if(!obj)returnfalse;
+if(obj==null)returnfalse;
 if(isAsync===true)returntypeofobj[SymbolAsyncIterator]==='function';
 if(isAsync===false)returntypeofobj[SymbolIterator]==='function';
 returntypeofobj[SymbolAsyncIterator]==='function'||

test/parallel/test-stream-pipeline-with-empty-string.js

@@ -0,0 +1,18 @@
+'use strict';
+
+constcommon=require('../common');
+const{
+ pipeline,
+ PassThrough
+}=require('stream');
+
+
+asyncfunctionrunTest(){
+awaitpipeline(
+'',
+newPassThrough({objectMode: true}),
+common.mustCall(()=>{})
+);
+}
+
+runTest().then(common.mustCall(()=>{}));