Feature: API for generating codeowners files

[ThisIsMissEm]

Hi!

I've recently been working on a project where I programmatically generate the codeowners file based on some configuration. So far, I've written a fairly simple class that gives an API to describe a codeowners file (rules, comments, and newlines), and I'm wondering if you'd like this contributed back?

I'm thinking more along the lines of parsing a CODEOWNERS file to a simple AST (see below), and then set of methods to work with that AST and a means to convert the AST to a CODEOWNERS file.

Example AST:

{
  type: 'rule' | 'comment' | 'newline'
  // For type == comment
  message?: string
  // For type == rule
  pattern: string
  owners: string[]
}

The Codeowners function would then change to:

// If options.read == true, then call Codeowners.prototype.readSync() followed by Codeowners.prototype.parse()
// options.read will default to true, as this closest resembles the existing behaviour
new Codeowners(currentPath, fileName = 'CODEOWNERS', options?: { read: true })
Codeowners.prototype.getOwner(filepath: string);

Codeowners.prototype.parse() // called by constructor

Codeowners.prototype.addComment(message?: string)
Codeowners.prototype.addRule(pattern: string, owners: string[])
Codeowners.prototype.addNewline()

Codeowners.prototype.toString() // output the current AST as a CODEOWNERS file

async Codeowners.prototype.read()
async Codeowners.prototype.write()

Codeowners.prototype.readSync()
Codeowners.prototype.writeSync()

Thoughts? This would allow programmatic management of CODEOWNERS files, we could also optionally do a breaking API change of:

new Codeowners(filepath: string, options?: { read: true });

Codeowners.discover(currentPath: string, filename = 'CODEOWNERS')

Such that existing code using the API would be:

- const owners = new Codeowners(workingDir);
+ const ownersFile = Codeowners.discover(workingDir);
+ const owners = new Codeowners(ownersFile, options?: { read: true });