Handle KO_DOCKER_REPO=ko.local/repo and --bare correctly (ko-build#820)

* Handle KO_DOCKER_REPO=ko.local/repo and --bare correctly

* support ko.local/foo for other namers too

* more robust defaulting

pkg/commands/resolver.go

@@ -172,10 +172,21 @@ func makePublisher(po *options.PublishOptions) (publish.Interface, error) {
 	innerPublisher, err := func() (publish.Interface, error) {
 		repoName := po.DockerRepo
 		namer := options.MakeNamer(po)
-		if strings.HasPrefix(repoName, publish.LocalDomain) || po.Local {
+		// Default LocalDomain if unset.
+		if po.LocalDomain == "" {
+			po.LocalDomain = publish.LocalDomain
+		}
+		// If repoName is unset with --local, default it to the local domain.
+		if po.Local && repoName == "" {
+			repoName = po.LocalDomain
+		}
+		// When in doubt, if repoName is under the local domain, default to --local.
+		po.Local = strings.HasPrefix(repoName, po.LocalDomain)
+		if po.Local {
 			// TODO(jonjohnsonjr): I'm assuming that nobody will
 			// use local with other publishers, but that might
 			// not be true.
+			po.LocalDomain = repoName
 			return publish.NewDaemon(namer, po.Tags,
 				publish.WithDockerClient(po.DockerClient),
 				publish.WithLocalDomain(po.LocalDomain),

pkg/commands/resolver_test.go

@@ -279,6 +279,15 @@ func TestNewPublisherCanPublish(t *testing.T) {
 			shouldError: true,
 			wantError:   errImageLoad,
 		},
+		{
+			description:   "bare with local domain and repo",
+			wantImageName: strings.ToLower(fmt.Sprintf("%s/foo", dockerRepo)),
+			po: &options.PublishOptions{
+				DockerRepo: dockerRepo + "/foo",
+				Local:      true,
+				Bare:       true,
+			},
+		},
 	}
 	for _, test := range tests {
 		t.Run(test.description, func(t *testing.T) {