Type alias Cache

Some Git commands can greatly benefit from a cache. Reading and parsing git packfiles (the files sent over the wire during clone, fetch, pull and push) can take a "long" time for large git repositories.

Unlike canonical git commands however, there is a way for git-essentials commands to cache intermediate results and re-use them between commands.

There is no single best caching strategy:

• For long-running processes, you may want to monitor memory usage and discard the cache when memory usage is above some threshold.
• For memory constrained devices, you may want to not use a cache at all.

Instead of compromising, the library have placed a powerful tool in your hands:

1. You pass in an ordinary cache object.
2. the library stores data on it by setting Symbol properties.
3. Manipulating the cache directly will void your warranty.
4. To clear the cache, remove any references to it so it is garbage collected.

Example

// PLEASE DON'T DO THIS!! This is for demonstration purposes only.
const test = async () => {
  console.time('time elapsed')
  let cache = {}
  for (const filepath of await listFiles({ fs, dir, cache })) {
    console.log(`${filepath}: ${await status({ fs, dir, filepath, cache })}`)
  }
  console.timeEnd('time elapsed')
}
test().catch(err => console.log(err))

The catch of course, is you have to decide when (if ever) to get rid of that cache. It is just a JavaScript object, so all you need to do is eliminate any references to it and it will be garbage collected.

// 1. Create a cache
let cache = {}
// 2. Do some stuff
// 3. Replace cache with new object so old cache is garbage collected
cache = {}