lib: always show ERR_INVALID_ARG_TYPE received part

This makes a effort to make sure all of these errors will actually
also show the received input.
On top of that it refactors a few tests for better maintainability.
It will also change the returned type to always be a simple typeof
instead of special handling null.

PR-URL: https://github.com/nodejs/node/pull/19445
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>

1 files changed, 4 insertions, 3 deletions

diff --git a/test/parallel/test-http2-getpackedsettings.js b/test/parallel/test-http2-getpackedsettings.js
index 56b9632113..77c8cf442f 100644
--- a/test/parallel/test-http2-getpackedsettings.js
+++ b/test/parallel/test-http2-getpackedsettings.js
@@ -99,14 +99,15 @@ http2.getPackedSettings({ enablePush: false });
     0x00, 0x00, 0x00, 0x64, 0x00, 0x06, 0x00, 0x00, 0x00, 0x64,
     0x00, 0x02, 0x00, 0x00, 0x00, 0x01]);
 
-  [1, true, '', [], {}, NaN].forEach((i) => {
+  [1, true, '', [], {}, NaN].forEach((input) => {
     common.expectsError(() => {
-      http2.getUnpackedSettings(i);
+      http2.getUnpackedSettings(input);
     }, {
       code: 'ERR_INVALID_ARG_TYPE',
       type: TypeError,
       message:
-        'The "buf" argument must be one of type Buffer, TypedArray, or DataView'
+        'The "buf" argument must be one of type Buffer, TypedArray, or ' +
+        `DataView. Received type ${typeof input}`
     });
   });