test: add common.noop, default for common.mustCall()

Export a new common.noop no-operation function for general use.
Allow using common.mustCall() without a fn argument to simplify
test cases.

Replace various non-op functions throughout tests with common.noop

PR-URL: https://github.com/nodejs/node/pull/12027
Reviewed-By: Jeremiah Senkpiel <fishrock123@rocketmail.com>
Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: Gibson Fahnestock <gibfahn@gmail.com>
Reviewed-By: Teddy Katz <teddy.katz@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Franziska Hinkelmann <franziska.hinkelmann@gmail.com>

1 files changed, 5 insertions, 5 deletions

diff --git a/test/parallel/test-stream-pipe-unpipe-streams.js b/test/parallel/test-stream-pipe-unpipe-streams.js
index 7e425aec1e..067b7f4482 100644
--- a/test/parallel/test-stream-pipe-unpipe-streams.js
+++ b/test/parallel/test-stream-pipe-unpipe-streams.js
@@ -4,15 +4,15 @@ const assert = require('assert');
 
 const { Readable, Writable } = require('stream');
 
-const source = Readable({read: () => {}});
-const dest1 = Writable({write: () => {}});
-const dest2 = Writable({write: () => {}});
+const source = Readable({read: common.noop});
+const dest1 = Writable({write: common.noop});
+const dest2 = Writable({write: common.noop});
 
 source.pipe(dest1);
 source.pipe(dest2);
 
-dest1.on('unpipe', common.mustCall(() => {}));
-dest2.on('unpipe', common.mustCall(() => {}));
+dest1.on('unpipe', common.mustCall());
+dest2.on('unpipe', common.mustCall());
 
 assert.strictEqual(source._readableState.pipes[0], dest1);
 assert.strictEqual(source._readableState.pipes[1], dest2);