Add `preact-compat/aliases` for consistent use between build tools

[ansballard]

Per #398 (comment)

I was looking into how devtools was split out in the preact repo, and I had a couple questions before diving into a pull request. Currently there's only the single rollup config at the root of the project, but preact has several within a config/ subdirectory. Would you prefer moving to the subdirectory with both the existing and alias config, or keeping both at the root?

Or, the existing rollup config could export an array of configs, since the new aliases.js should be pretty minimal (module.exports = { /* insert 3-line json here */ };). Just wanted to see if you had a preference.

[developit]

I love this idea. Personally I prefer a single rollup config, but in this case it seems like we could get away with just using ES5 + CommonJS and not even transpiling it?

[ansballard]

Yep, I figured that would probably be the simplest option. It shouldn't hurt anything to not export an es6 version, and all the other options involve changing the structure of the project in some way. Unless someone else jumps in before me I'll try to get a pull request in tonight after work!

[developit]

Would love a PR if anyone has time! :)

[ansballard]

Took a minute to at least figure out what all needs to be included, since I'm lame and never got into this:

• a straightforward aliases.js file in the root that exports all necessary aliases
• file should not use es6 exports so it doesn't have to be transpiled (module.exports = { ... })
• docs/working example using webpack (just import in the webpack config and ... it in the resolve section)
• docs/working example using browserify (use a separate aliasify config and reference it in package.json like this)
• docs/working example using babel (babel 7 allows for .babelrc.js, which would allow requiring the same as above, but until that is released maybe a hack with local presets like this?
• docs/working example using brunch (never used it, seems pretty similar to the others since it's a js config file)

[marvinhagemeister]

Looks like this has been resolved by using microbundle in our main repo 👍