Why is prettier-atom so slow on large .svelte files?

Clone and install:

git clone git@github.com:severo/atom_prettier_svelte.git
cd atom_prettier_svelte
yarn

Install Atom and Prettier for Atom.

Open each of the src/ files in Atom, and try to save them:

• block.js - instantaneous
• Short.svelte - quick
• Long.svelte - very slow (~30s on my machine)

Note that the CLI is instantaneous:

npx prettier --write src/*