Release custom versions on each build

[cyberhck]

New feature motivation

Let's say I'm a library author and there's a new version, even though all tests have passed, I'd like to actually use it before I merge, so something like -RC+ (convention can be something else, I'm sure we can find something better.

Let me give an example with totally random numbers, so if I have a PR and current version was 0.1.8, and the PR identifier is 103, and travis build ID is 182302, then a 0.1.8-RC103+182302 (obviously naming will be different which doesn't break semantic versioning)

New feature description

I think current workflow should stay as it is, if we start releasing on each PR, people might get mad, I'd say have a flag something like --enable-rc-publishing (I'm very bad at naming, you guys will do a better job at this), if the flag is present, we start doing this, and on master, we simply do what we would have done.

I think we should also add a setup where only branch with certain naming pattern will do this, for instance, anything starting with "RC" branch will publish this, but individual PRs won't, totally up to author.

New feature implementation

I'm not sure of this. I've never implemented a plugin, and I've definitely not digged into semantic-release's source code either.

It might be a lot of work, but it'd make workflow so much better.

Please express your thoughts on this.

[travi]

have you seen the support for pre-releases that is available in the beta version of semantic-release? what you describe sounds like it would largely be satisfied by that support: https://github.com/semantic-release/semantic-release/blob/beta/docs/recipes/pre-releases.md

[pvdlg]

Closing as answered in #1096 (comment). Already implemented in v16.0.0