optimize-deps-filter.md

Context

Currently

• optimizeDeps.include is a list of entries to pre-add to the optimized list
• optimizeDeps.exclude is a list of package names or entry names that will be excluded (works by checking both the id and the pkgId for each value)

#12414 proposes to add support for globs in optimizeDeps.include

Sheremet is looking to replace inline by optimizeDeps.include in Vitest.

Options

1. modify the meaning of optimizeDeps.include/exclude with a flag

• a new option optimizeDeps.byDefault: false that would make include/exclude work like a regular createFilter over found dependencies
  • optimizeDeps.include supports globs
  • optimizeDeps.exclude supports globs

I don't think we should do this, as it is confusing that the semantics of include from "pre-add these deps" to "work as createFilter include".

2. Add a new optimizeDeps.autoDiscovery: false

Keep include/exclude as is, but only dependencies listed in optimizeDeps.include (and not excluded) would be optimized.

This option will also turn off the scanner (same effect as optimizeDeps.entries: []).

3. ignoreMissing: true

Same effect as 2., but having optimizeDeps.ignoreMissing: true to ignore dependencies when found while resolving. The user will need to turn off the scanner with entries: [] too. I prefer 2. because the scanner is conceptually an optimization, the option should affect both deps found by resolving or by the scanner to me.

4. Add a new optimizeDeps.filter

• optimizeDeps.filter that could be a (id: string) => boolean (by default is () => true). We could also have { include, exclude } but it may be confusing with the other options. So Vitest could use filter to only optimize certain deps.