commands,t: report invalid ref in push command

Unlike the "git lfs fetch" command, the "git lfs push" command does
not currently report an error if an invalid ref is provided as a
command-line argument, so we update the command to output an error
message in this situation, and we add a test to confirm the new
behaviour works as expected.

Note that in contrast to the "git lfs fetch" command's older
implementation of this type of check, we simply report an error message
when an invalid ref is encountered, rather than calling our Panic()
function and also writing a stack trace to a log file.  This approach is
more in keeping with how many of our commands now handle similar error
conditions; e.g., the "git lfs fsck" and "git lfs migrate" commands
call ExitWithError() rather than Panic() when refs cannot be resolved.

Co-authored-by: Philip Peterson <[email protected]>

commands/command_push.go

@@ -157,6 +157,9 @@ func lfsPushRefs(refnames []string, pushAll bool) ([]*git.RefUpdate, error) {
 			refs[i] = git.NewRefUpdate(cfg.Git, cfg.PushRemote(), ref, nil)
 		} else {
 			ref := &git.Ref{Name: name, Type: git.RefTypeOther, Sha: name}
+			if _, err := git.ResolveRef(name); err != nil {
+				return nil, errors.New(tr.Tr.Get("Invalid ref argument: %v", name))
+			}
 			refs[i] = git.NewRefUpdate(cfg.Git, cfg.PushRemote(), ref, nil)
 		}
 	}

t/t-push.sh

@@ -38,6 +38,16 @@ begin_test "push with tracked ref"
 )
 end_test
 
+begin_test "push with invalid ref"
+(
+  set -e
+  push_repo_setup "push-invalid-branch-required"
+
+  git lfs push origin jibberish >push.log 2>&1 && exit 1
+  grep "Invalid ref argument" push.log
+)
+end_test
+
 begin_test "push with bad ref"
 (
   set -e