test: refactor test-http-information-processing

Replace magic numbers with constant.
Use for loop for repeated code.
Reduce console logging.
Remove unneeded countdown module use.

PR-URL: nodejs#32547
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

test/parallel/test-http-information-processing.js

@@ -2,22 +2,21 @@
 require('../common');
 const assert = require('assert');
 const http = require('http');
-const Countdown = require('../common/countdown');
 
-const test_res_body = 'other stuff!\n';
-const countdown = new Countdown(3, () => server.close());
+const testResBody = 'other stuff!\n';
+const kMessageCount = 2;
 
 const server = http.createServer((req, res) => {
-  console.error('Server sending informational message #1...');
-  res.writeProcessing();
-  console.error('Server sending informational message #2...');
-  res.writeProcessing();
+  for (let i = 0; i < kMessageCount; i++) {
+    console.error(`Server sending informational message #${i}...`);
+    res.writeProcessing();
+  }
   console.error('Server sending full response...');
   res.writeHead(200, {
     'Content-Type': 'text/plain',
     'ABCD': '1'
   });
-  res.end(test_res_body);
+  res.end(testResBody);
 });
 
 server.listen(0, function() {
@@ -29,24 +28,22 @@ server.listen(0, function() {
   console.error('Client sending request...');
 
   let body = '';
+  let infoCount = 0;
 
-  req.on('information', function(res) {
-    console.error('Client got 102 Processing...');
-    countdown.dec();
-  });
+  req.on('information', () => { infoCount++; });
 
   req.on('response', function(res) {
     // Check that all 102 Processing received before full response received.
-    assert.strictEqual(countdown.remaining, 1);
+    assert.strictEqual(infoCount, kMessageCount);
     assert.strictEqual(res.statusCode, 200,
                        `Final status code was ${res.statusCode}, not 200.`);
     res.setEncoding('utf8');
     res.on('data', function(chunk) { body += chunk; });
     res.on('end', function() {
       console.error('Got full response.');
-      assert.strictEqual(body, test_res_body);
+      assert.strictEqual(body, testResBody);
       assert.ok('abcd' in res.headers);
-      countdown.dec();
+      server.close();
     });
   });
 });