early exit if all branches merged

Author: skarim

README.md

@@ -283,7 +283,7 @@ Push all branches and create/update PRs and the stack on GitHub.
 gh stack submit [flags]
 ```
 
-Creates a Stacked PR for every branch in the stack, pushing branches to remote if needed.
+Creates a Stacked PR for every branch in the stack, pushing branches to the remote.
 
 After creating PRs, `submit` automatically creates a **Stack** on GitHub to link the PRs together. If the stack already exists on GitHub (e.g., from a previous submit), new PRs will be added to the top of the stack.
 

cmd/push.go

@@ -76,6 +76,10 @@ func runPush(cfg *config.Config, opts *pushOptions) error {
 		cfg.Printf("Skipping %d merged %s", len(merged), plural(len(merged), "branch", "branches"))
 	}
 	activeBranches := activeBranchNames(s)
+	if len(activeBranches) == 0 {
+		cfg.Printf("No active branches to push (all merged)")
+		return nil
+	}
 	cfg.Printf("Pushing %d %s to %s...", len(activeBranches), plural(len(activeBranches), "branch", "branches"), remote)
 	if err := git.Push(remote, activeBranches, true, true); err != nil {
 		cfg.Errorf("failed to push: %s", err)

cmd/rebase.go

@@ -324,8 +324,8 @@ func runRebase(cfg *config.Config, opts *rebaseOptions) error {
 	}
 
 	cfg.Printf("%s rebased locally with %s", rangeDesc, s.Trunk.Branch)
-	cfg.Printf("To push up your changes and open/update the stack of PRs, run `%s`",
-		cfg.ColorCyan("gh stack submit"))
+	cfg.Printf("To push up your changes, run `%s`",
+		cfg.ColorCyan("gh stack push"))
 
 	return nil
 }

cmd/submit.go

@@ -90,6 +90,10 @@ func runSubmit(cfg *config.Config, opts *submitOptions) error {
 		cfg.Printf("Skipping %d merged %s", len(merged), plural(len(merged), "branch", "branches"))
 	}
 	activeBranches := activeBranchNames(s)
+	if len(activeBranches) == 0 {
+		cfg.Printf("All branches are merged, nothing to submit")
+		return nil
+	}
 	cfg.Printf("Pushing %d %s to %s...", len(activeBranches), plural(len(activeBranches), "branch", "branches"), remote)
 	if err := git.Push(remote, activeBranches, true, true); err != nil {
 		cfg.Errorf("failed to push: %s", err)
@@ -304,14 +308,14 @@ func handleCreate422(cfg *config.Config, httpErr *api.HTTPError) {
 	msg := httpErr.Message
 
 	if strings.Contains(msg, "already stacked") {
-		cfg.Errorf("One or more PRs are already part of an existing stack on GitHub")
+		cfg.Warningf("One or more PRs are already part of an existing stack on GitHub")
 		cfg.Printf("  To fix this, unstack the PRs from the web, then `%s`",
 			cfg.ColorCyan("gh stack submit"))
 		return
 	}
 
 	if strings.Contains(msg, "must form a stack") {
-		cfg.Errorf("Cannot create stack: %s", msg)
+		cfg.Warningf("Cannot create stack: %s", msg)
 		cfg.Printf("  Each PR's base branch must match the previous PR's head branch.")
 		return
 	}