internal/lsp/cache: don't panic in Snapshot on a shutdown view
There are many places where we may use a view asynchronously while it is
shutting down. In these cases, it should be fine to fail or skip the
view when we fail to acquire its snapshot.
Fixes golang/go#56466
Change-Id: Icc4edfc1b951c40c8aa42a18ba4ecbf85621523d
Reviewed-on: https://go-review.googlesource.com/c/tools/+/462820
Run-TryBot: Robert Findley <rfindley@google.com>
gopls-CI: kokoro <noreply+kokoro@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Alan Donovan <adonovan@google.com>
diff --git a/gopls/internal/lsp/cache/snapshot.go b/gopls/internal/lsp/cache/snapshot.go
index 0eef84e..51d7a79 100644
--- a/gopls/internal/lsp/cache/snapshot.go
+++ b/gopls/internal/lsp/cache/snapshot.go
@@ -43,7 +43,16 @@
type snapshot struct {
sequenceID uint64
globalID source.GlobalSnapshotID
- view *View
+
+ // TODO(rfindley): the snapshot holding a reference to the view poses
+ // lifecycle problems: a view may be shut down and waiting for work
+ // associated with this snapshot to complete. While most accesses of the view
+ // are benign (options or workspace information), this is not formalized and
+ // it is wrong for the snapshot to use a shutdown view.
+ //
+ // Fix this by passing options and workspace information to the snapshot,
+ // both of which should be immutable for the snapshot.
+ view *View
cancel func()
backgroundCtx context.Context
