Git Utils fileMatch API design

Looks like a core bit of the git util functionality was removed with a refactor.

https://github.com/netlify/build/blame/master/packages/git-utils/README.md#L48-L53

The fileMatch function should return a function that

Original code:

const micromatch = require('micromatch')
const mapValues = require('lodash.mapvalues')

const isExclude = p => p.startsWith('!')

module.exports = function fileMatcher(keyedPaths) {
  function matchPatterns(patterns) {
    return mapValues(keyedPaths, paths => {
      const excludePatterns = patterns.filter(p => isExclude(p))
      const includePatterns = patterns.filter(p => !isExclude(p))
      const included = includePatterns.reduce((accum, pattern) => accum.concat(micromatch.match(paths, pattern)), [])
      return excludePatterns.reduce((accum, pattern) => micromatch.match(accum, pattern), included)
    })
  }
  function finalize(keyedPaths) {
    return Object.assign(
      Object.assign(
        {},
        mapValues(keyedPaths, paths => paths.length > 0),
      ),
      { getKeyedPaths: () => keyedPaths },
    )
  }
  return (...patterns) => finalize(matchPatterns(patterns))
}

getKeyedPaths returns an object that looks like:

{ 
  modified: [ 'example.js', 'src/LocalGit.js' ],
  created: [ 'src/index.js' ],
  deleted: [ 'src/git/_tests/local_dangerfile_example.js' ],
  edited: [ 'example.js',  'src/index.js' ] 
}

This is quite important for advanced diffing functionality.

Can we please get this back in

[jlengstorf]

I think I prefer option 2 as well

the keys could return false as well if no files come back, which would further simplify usage:

const cssFiles = git.fileMatch('**/*.css');

if (!cssFiles.editedFiles) return;

// do stuff

I think there’s also an argument to drop the *Files part for keys; I’m not sure it adds additional clarity vs:

const cssFiles = git.fileMatch('**/*.css');

if (!cssFiles.edited) return;

if (cssFiles.edited.includes('just-changed.css')) {
  // do stuff
}

[ehmicky]

Done at #722.