test: improve test-process-kill-null for Windows

PR-URL: #14099
Reviewed-By: Refael Ackermann <refack@gmail.com>

test/parallel/test-process-kill-null.js

@@ -20,29 +20,23 @@
 // USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 'use strict';
-require('../common');
+const common = require('../common');
 const assert = require('assert');
 const spawn = require('child_process').spawn;
 
-const cat = spawn('cat');
-let called;
+const child = common.isWindows ? spawn('cmd.exe') : spawn('cat');
 
-assert.ok(process.kill(cat.pid, 0));
+assert.ok(process.kill(child.pid, 0));
 
-cat.on('exit', function() {
+child.on('exit', common.mustCall(function() {
   assert.throws(function() {
-    process.kill(cat.pid, 0);
+    process.kill(child.pid, 0);
   }, Error);
-});
+}));
 
-cat.stdout.on('data', function() {
-  called = true;
-  process.kill(cat.pid, 'SIGKILL');
-});
+child.stdout.on('data', common.mustCall(function() {
+  process.kill(child.pid, 'SIGKILL');
+}));
 
 // EPIPE when null sig fails
-cat.stdin.write('test');
-
-process.on('exit', function() {
-  assert.ok(called);
-});
+child.stdin.write('test');