tree a09bacaa3b0781d921a946ffa00902f0c0e8eb82
parent ac3e9e73d10cde27fb15c6d6a477a690bef08cb2
author Heschi Kreinick <heschi@google.com> 1577405638 -0500
committer Heschi Kreinick <heschi@google.com> 1577740222 +0000

internal/imports: redesign scan API

We have multiple use cases for scanning: goimports, import completion,
and unimported completions. All three need slightly different features,
and the latter have very different performance considerations. Scanning
everything all at once and returning it was not good enough for them.

Instead, design the API as a series of callbacks for each
directory/package: first we discover its existence, then we load its
package name, then we load its exports. At each step the caller can
choose whether to proceed with the package. Import completion can stop
before loading exports, goimports can apply its directory name
heuristics, and in the future we'll be able to stop the scan short once
we've found all the results we want for completions.

I don't intend any significant changes here but there may be some little
ones around the edges.

Change-Id: I39c3aa08cc0e4793c280242c342770f62e101364
Reviewed-on: https://go-review.googlesource.com/c/tools/+/212631
Run-TryBot: Heschi Kreinick <heschi@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rebecca Stambler <rstambler@golang.org>