feat(core): add kebab-case, camelCase, PascalCase options

[navarroaxel]

I know this need more unit test cases. You think this is the way?

[marionebl]

Great work and some comments from me. Could you make sure to remove the yarn.lock file?

[marionebl]

Could you remove those and add .idea to .gitignore?

[navarroaxel]

Why do you commit the .vscode? We can add **/.*/ to ignore all the IDEs generated files.

[marionebl]

The .vscode directory contains config I'd like to share with other vscode users. Afaik the .idea directory is specific to each machine

[marionebl]

I'd prefer each case returning on its own, e.g. return input === camelCase(input). That would avoid thelet, too.

[navarroaxel]

It's not logic duplicated? I want avoid that putting the equality compare only one time.

[marionebl]

Given all of them are strict equality checks I'd choose this direction, yes.

[marionebl]

Please remove, lodash is a dependency of @commitlint/core already

[navarroaxel]

Oh. I didn't know that. This is my first time with lerna.

[navarroaxel]

Let me know if this is OK to add more unit test cases for scope, type and subject

[marionebl]

Looks good.
The test cases for type and subject would be good to define the corresponding behaviour.

[navarroaxel]

5 tests are failing becaue the type part does not support Start Case. What we can do with that? Support spaces on the type or do not support Start Case as a valid option for type ?

[marionebl]

The parser-preset option allows for non-angular headerPattern settings, making Start Case types possible - I think we should support that.

[navarroaxel]

How should I change the 5 tests to pass?

[marionebl]

I am completely swamped with day-work at the moment, sorry. I'll have time to provide an example next week the soonest.

You'll want to use the second parameter of parse to pass a headerPattern and headerCorrespondence to conventional-commits-parse allowing for whitespace in the field you want to test.

An example for parserConfiguration can be found here: https://github.com/marionebl/commitlint/blob/master/%40commitlint/cli/fixtures/parser-preset/parser-preset.js

[navarroaxel]

The test are failing because the type is empty with Start Case so the type empty is succeed with every option (i.e. camelCase). Maybe the defaultChangelogOpts should be changed to fail with spaces before the :.

[marionebl]

Landing this with changes via https://github.com/marionebl/commitlint/pull/84