cmd/gorelease: use -mod=mod when listing packages
This fixes test failures when gorelease is used with the tip Go 1.16.
For golang/go#41456
Change-Id: I9a1452518113f595d9c94fb394f0aecbcc80b95f
Reviewed-on: https://go-review.googlesource.com/c/exp/+/255597
Trust: Jay Conrod <jayconrod@google.com>
Trust: Jean de Klerk <deklerk@google.com>
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Jean de Klerk <deklerk@google.com>
diff --git a/cmd/gorelease/gorelease.go b/cmd/gorelease/gorelease.go
index b369332..cc65a28 100644
--- a/cmd/gorelease/gorelease.go
+++ b/cmd/gorelease/gorelease.go
@@ -909,8 +909,20 @@
// We can't just load example.com/mod/... because that might include packages
// in nested modules. We also can't filter packages from the output of
// packages.Load, since it doesn't tell us which module they came from.
+ //
+ // TODO(golang.org/issue/41456): this command fails in -mod=readonly mode
+ // if sums are missing, which they always are for downloaded modules. In
+ // Go 1.16, -mod=readonly is the default, and -mod=mod may eventually be
+ // removed, so we should avoid -mod=mod here. Lazy loading may also require
+ // changes to temporary module requirements.
+ //
+ // Instead of running this command, we should make a list of importable
+ // packages by walking the directory tree. With such a list,
+ // in prepareLoadDir, we could generate a temporary package that imports
+ // all of them, then 'go get -d' that package to ensure no requirements
+ // or sums are missing.
format := fmt.Sprintf(`{{if .Module}}{{if eq .Module.Path %q}}{{.ImportPath}}{{end}}{{end}}`, modPath)
- cmd := exec.Command("go", "list", "-e", "-f", format, "--", modPath+"/...")
+ cmd := exec.Command("go", "list", "-mod=mod", "-e", "-f", format, "--", modPath+"/...")
cmd.Dir = loadDir
out, err := cmd.Output()
if err != nil {
