test: rewrite test-child-process-spawn-args

- Use ESM for top-level await
- Avoid concurrent child processes in the test
- Use `events.once` instead of Promise wrapper
- Assert directly on sets
PR-URL: #58546
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: LiviaMedeiros <livia@cirno.name>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

Author: targos

test/parallel/test-child-process-spawn-args.js

@@ -0,0 +1,50 @@
+// This test confirms that `undefined`, `null`, and `[]`
+// can be used as a placeholder for the second argument (`args`) of `spawn()`.
+// Previously, there was a bug where using `undefined` for the second argument
+// caused the third argument (`options`) to be ignored.
+// See https://github.com/nodejs/node/issues/24912.
+
+import*ascommonfrom'../common/index.mjs';
+importtmpdirfrom'../common/tmpdir.js';
+
+importassertfrom'node:assert';
+import{spawn}from'node:child_process';
+import{once}from'node:events';
+
+tmpdir.refresh();
+
+constcommand=common.isWindows ? 'cd' : 'pwd';
+constoptions={cwd: tmpdir.path};
+
+if(common.isWindows){
+// This test is not the case for Windows based systems
+// unless the `shell` options equals to `true`
+options.shell=true;
+}
+
+consttestCases=[
+undefined,
+null,
+[],
+];
+
+constexpectedResult=newSet([tmpdir.path.trim().toLowerCase()]);
+
+constactualResults=newSet();
+
+for(consttestCaseoftestCases){
+constsubprocess=spawn(command,testCase,options);
+
+letaccumulatedData='';
+
+subprocess.stdout.setEncoding('utf8');
+subprocess.stdout.on('data',common.mustCall((data)=>{
+accumulatedData+=data;
+}));
+
+awaitonce(subprocess.stdout,'end');
+
+actualResults.add(accumulatedData.trim().toLowerCase());
+}
+
+assert.deepStrictEqual(actualResults,expectedResult);