A lot of the time spent for every file change is recomputing the set of
known subdirectories in the workspace. We can easily memoize these known
subdirectories and avoid recomputing them on every file change. Do that
here and update the set as file creations and deletions come in.
Updates golang/go#45686Fixesgolang/go#45974
Change-Id: Ide07f7c90f0cafc3a3cc7b89ba14ab82d4e3ab28
Reviewed-on: https://go-review.googlesource.com/c/tools/+/317410
Trust: Rebecca Stambler <rstambler@golang.org>
Run-TryBot: Rebecca Stambler <rstambler@golang.org>
gopls-CI: kokoro <noreply+kokoro@google.com>
Reviewed-by: Robert Findley <rfindley@google.com>
TryBot-Result: Go Bot <gobot@golang.org>