Feature Request: Support changesets for repos with multiple releases per package

The Problem

I have a simple repo which looks like this:

index.js

module.exports = () => {
  if (process.env.PLATFORM === 'web') {
    console.log('Hi web');
  } else if (process.env.PLATFORM === 'ios') {
    console.log('Hi Steve');
  } else {
    console.log('Beep Boop'); // Android
  }
}

And I have a build process setup:

(imaging there's a webpack config here)

Important to note in this build process is the output bundle changes depending on the value of PLATFORM env var.

End goal

Because I have two separate platforms generated from the one codebase, I also want two separate changelogs generated.

For example, I may want:

changelog-ios.md

# beingawesome

## 1.0.0
### Major Changes
- Initial release

changelog-web.md

# beingawesome

## 1.0.0
### Major Changes
- Initial release

… etc.

But now I realise there’s a bug on iOS, so I do a fix:

index.js

-    console.log('Hi Steve');
+    console.log('Hi iOS');

So now I want to release only the ios variant (PLATFORM=ios).

Which means I only want to generate a change to the changelog-ios.md file:

changelog-ios.md

 # beingawesome

+## 1.0.1
+### Patch Changes
+- Fix output for iOS

 ## 1.0.0
 ### Major Changes
 - Initial release

Alternative

Alternatively, the changelogs may be combined into one:

changelog.md

# beingawesome

## Android 1.0.0
### Major Changes
- Initial release

## iOS 1.0.0
### Major Changes
- Initial release

Then the above change would look like:

 # beingawesome

+## iOS 1.0.1
+### Patch Changes
+- Fix output for iOS

 ## Android 1.0.0
 ### Major Changes
 - Initial release

 ## iOS 1.0.0
 ### Major Changes
 - Initial release

Proposed solution

?

[Noviny]

Thanks for raising this!

There’s a bit of a bigger thing that might require some sparring (assuming you only have one package.json, have you bumped it to 1.0.1 - what does that mean for next time you release android)

as well as the fact that changelogs currently allow you to generate lines but not the whole added block.

The changelog generation is something we want to rethink at some point to get a right mix between ‘I can have exactly my preferred format’ and 'this is easy to set up and I don’t have to think about it.

---

If we move a bit slow and you need this, I’d recommend writing a custom version command that would look something like:

async function customVersion() {
  let releasePlan = await getReleasePlan()

  applyReleasePlan(releasePlan, { changelog: false })

  customChangelogWriter(releasePlan)
}

[emmatown]

Yep, that.