test: fs.write() if 3rd argument is a callback, not offset

Easier way to resolve conflicts from #16822 and #16827. PR-URL: #17045 Reviewed-By: Anna Henningsen <[email protected]> Reviewed-By: Colin Ihrig <[email protected]>

Author: Patrick Heneise

test/parallel/test-fs-write.js

@@ -26,6 +26,7 @@ const path = require('path');
 constfs=require('fs');
 constfn=path.join(common.tmpDir,'write.txt');
 constfn2=path.join(common.tmpDir,'write2.txt');
+constfn3=path.join(common.tmpDir,'write3.txt');
 constexpected='ümlaut.';
 constconstants=fs.constants;
 
@@ -73,3 +74,15 @@ fs.open(fn2, args, 0o644, common.mustCall((err, fd) =>{
 fs.write(fd,'',0,'utf8',written);
 fs.write(fd,expected,0,'utf8',done);
 }));
+
+fs.open(fn3,'w',0o644,common.mustCall(function(err,fd){
+assert.ifError(err);
+
+constdone=common.mustCall(function(err,written){
+assert.ifError(err);
+assert.strictEqual(Buffer.byteLength(expected),written);
+fs.closeSync(fd);
+});
+
+fs.write(fd,expected,done);
+}));