The code should likely be a bit more specific... e.g. ERR_TLS_RENEGOTIATION_FAILED, etc

+1

Done!

ERR_TLS_SERVER_NAME_REQUIRED

Done!

this would need to be

assert.strictEqual(e.code, 'ERR_DH_PARAM_SIZE');

In this file, e is of type Object Error. This doesn't have the field e.code which we can access, so I believe, this one will be more appropriate in that case.

I have written a small test-case and verified that:

var u = require('util')
var e = new Error('ERR_DH_PARAM_SIZE');
console.log(u.inspect(e, {showHidden: true}))`

Output:

 at Object.<anonymous> (/home/bidisha/swe_node/n1/node/foo.js:2:9)
    at Module._compile (module.js:569:30)
    at Object.Module._extensions..js (module.js:580:10)
    at Module.load (module.js:503:32)
    at tryModuleLoad (module.js:466:12)
    at Function.Module._load (module.js:458:3)
    at Function.Module.runMain (module.js:605:10)
    at startup (bootstrap_node.js:158:16)
    at bootstrap_node.js:575:3
  [stack]: 'Error: ERR_DH_PARAM_SIZE\n    at Object.<anonymous> (/home/bidisha/swe_node/n1/node/foo.js:2:9)\n    at Module._compile (module.js:569:30)\n    at Object.Module._extensions..js (module.js:580:10)\n    at Module.load (module.js:503:32)\n    at tryModuleLoad (module.js:466:12)\n    at Function.Module._load (module.js:458:3)\n    at Function.Module.runMain (module.js:605:10)\n    at startup (bootstrap_node.js:158:16)\n    at bootstrap_node.js:575:3',
  [message]: 'ERR_DH_PARAM_SIZE' }`

Please suggest on this.

Sorry for the incorrect observation above.
Now, things seems to be resolved.
Thanks!

+1

maybe 'ERR_TLS_SESSION_CALLBACK_ALREADY_CALLED'

Done.
Thank You!

Maybe add "_ALREADY_CALLED" to these 2 as well. It does make the code long but it also makes it clearer what's going wrong.

Done.

s/ERR_RENEGOTIATE/ERR_TLS_RENEGOTIATE ?

s/ERR_REQD_SERVER_NAME/ERR_TLS_REQUIRED_SERVER_NAME ?

s/ERR_DH_PARAM_SIZE/ERR_TLS_DH_PARAM_SIZE ?

this is hard coding the param size. it shouldn't be.

E('ERR_DH_PARAM_SIZE', (size) => `DH parameter size ${size} is less than 2048`);

I would take the opportunity to reword this a bit:

'The session callback was called more than once'

Actually... making this a generic error would make more sense, e.g.

E('ERR_MULTIPLE_CALLBACK',
    (name) => `The ${name} callback was called more than once`);

There is a merge problem here. @bidipyne can you take a look/fix up

Done that fix. Thanks @mhdawson

This is a rebase leak...
Could you go over this list and keep only the ERRs you need for this PR

Removed all unrelated ERRs to this PR. Thanks! @refack.

This is a redefinition of ERR_MULTIPLE_CALLBACK from L162 this causes the error message to change.

1. You can just remove this one and use the one in L162
2. You can remove this one and improve L162 (and update its usages)
3. [Optional] You could sort this whole block alphabetically (very easy if your IDE supports that, otherwise ignore)
4. You can open an issue that E() doesn't fail for redefinition, or even better a PR that makes it fail 😉

not ok 1108 parallel/test-stream-transform-callback-twice
  ---
  duration_ms: 0.61
  severity: fail
  stack: |-
    assert.js:55
      throw new errors.AssertionError({
      ^
    
    AssertionError [ERR_ASSERTION]: 'The undefined callback was called more than once' === 'Callback called multiple times'
        at Transform.<anonymous> (/data/iojs/build/workspace/node-test-commit-linuxone/nodes/rhel72-s390x/test/common/index.js:716:14)
        at emitOne (events.js:115:13)
        at Transform.emit (events.js:210:7)
        at Transform.afterTransform (_stream_transform.js:80:17)
        at Transform.transform [as _transform] (/data/iojs/build/workspace/node-test-commit-linuxone/nodes/rhel72-s390x/test/parallel/test-stream-transform-callback-twice.js:5:37)
        at Transform._read (_stream_transform.js:185:10)
        at Transform._write (_stream_transform.js:173:12)
        at doWrite (_stream_writable.js:371:12)
        at writeOrBuffer (_stream_writable.js:357:5)
        at Transform.Writable.write (_stream_writable.js:274:11)
  ...

https://ci.nodejs.org/job/node-test-commit-linuxone/7151/

Thanks for the suggestion @refack
I have redefined the error message accordingly but this lead to change of another test file: test-stream-transform-callback-twice.js
Hope that is fine with this PR.
Thank you!

The change to test-stream-transform-callback-twice.js is good by me, but IMHO you should just remote L162, since this line simply overrides it anyway (there's no other magic).

The change to test-stream-transform-callback-twice.js is good by me, but IMHO you should just remote L162, since this line simply overrides it anyway (there's no other magic).

This does not look right to me. 'The undefined callback...'

I have reverted the message back back. Please have a look!

Related to my comment above. Agree with @refack that the duplicate line above needs to be removed.

Removed!

Should we not be updating the code that generates this error so that it does not have 'undefined' but an indication of what the callback is ?

Referring to the suggestions above, error message on this file is also redefined.
Please suggest me on that!
Thank You! @mhdawson

The only remaining thing I see here is making sure that the error codes are in alphabetical order.