waterfall pr lookup by url, number, branch name

Author: skarim

cmd/checkout.go

@@ -3,7 +3,6 @@ package cmd
 import (
 	"errors"
 	"fmt"
-	"strconv"
 
 	"github.com/cli/go-gh/v2/pkg/prompter"
 	"github.com/github/gh-stack/internal/config"
@@ -82,11 +81,13 @@ func runCheckout(cfg *config.Config, opts *checkoutOptions) error {
 		targetBranch = s.Branches[len(s.Branches)-1].Branch
 	} else {
 		// Resolve target against local stacks
-		s, targetBranch, err = findStackByTarget(sf, opts.target)
+		var br *stack.BranchRef
+		s, br, err = resolvePR(sf, opts.target)
 		if err != nil {
 			cfg.Errorf("%s", err)
 			return nil
 		}
+		targetBranch = br.Branch
 	}
 
 	currentBranch, _ := git.CurrentBranch()
@@ -106,36 +107,6 @@ func runCheckout(cfg *config.Config, opts *checkoutOptions) error {
 	return nil
 }
 
-// findStackByTarget resolves a target string against locally tracked stacks.
-// It tries PR number first (integer), then branch name.
-func findStackByTarget(sf *stack.StackFile, target string) (*stack.Stack, string, error) {
-	// Try parsing as a PR number
-	if prNumber, err := strconv.Atoi(target); err == nil && prNumber > 0 {
-		s, b := sf.FindStackByPRNumber(prNumber)
-		if s != nil && b != nil {
-			return s, b.Branch, nil
-		}
-	}
-
-	// Try matching as a branch name
-	stacks := sf.FindAllStacksForBranch(target)
-	if len(stacks) == 1 {
-		return stacks[0], target, nil
-	}
-	if len(stacks) > 1 {
-		// Target is in multiple stacks (e.g. a trunk branch) — return the first one.
-		// A future improvement could prompt for disambiguation here.
-		return stacks[0], target, nil
-	}
-
-	return nil, "", fmt.Errorf(
-		"no locally tracked stack found for %q\n"+
-			"This command currently only works with stacks created locally.\n"+
-			"Server-side stack discovery will be available in a future release.",
-		target,
-	)
-}
-
 // interactiveStackPicker shows a menu of all locally tracked stacks and returns
 // the one the user selects. Returns nil, nil if the user has no stacks.
 func interactiveStackPicker(cfg *config.Config, sf *stack.StackFile) (*stack.Stack, error) {

cmd/merge.go

@@ -1,31 +1,113 @@
 package cmd
 
 import (
+	"fmt"
+
+	"github.com/cli/go-gh/v2/pkg/browser"
+	"github.com/cli/go-gh/v2/pkg/prompter"
 	"github.com/github/gh-stack/internal/config"
+	"github.com/github/gh-stack/internal/stack"
 	"github.com/spf13/cobra"
 )
 
 func MergeCmd(cfg *config.Config) *cobra.Command {
-	opts := struct{}{}
-
 	cmd := &cobra.Command{
-		Use:   "merge <pr>",
+		Use:   "merge [<pr-or-branch>]",
 		Short: "Merge a stack of PRs",
-		Long:  "Merges the specified PR and all PRs below it in the stack.",
-		Args:  cobra.ExactArgs(1),
+		Long: `Merges the specified PR and all PRs below it in the stack.
+
+Accepts a PR URL, PR number, or branch name. When run without
+arguments, operates on the current branch's PR.`,
+		Args: cobra.MaximumNArgs(1),
 		RunE: func(cmd *cobra.Command, args []string) error {
-			return runMerge(cfg, opts)
+			var target string
+			if len(args) > 0 {
+				target = args[0]
+			}
+			return runMerge(cfg, target)
 		},
 	}
 
 	return cmd
 }
 
-// runMerge is a placeholder for the stack merge workflow.
-//
-// We need a mergeability check for the entire stack
-// and an endpoint for merging an entire stack
-func runMerge(cfg *config.Config, opts struct{}) error {
-	cfg.Warningf("`%s` is not yet implemented", cfg.ColorCyan("gh stack merge"))
+func runMerge(cfg *config.Config, target string) error {
+	// Standard stack loading and validation.
+	result, err := loadStack(cfg, "")
+	if err != nil {
+		return nil
+	}
+	s := result.Stack
+	currentBranch := result.CurrentBranch
+
+	// Sync PR state from GitHub so merge status is up to date.
+	syncStackPRs(cfg, s)
+
+	// Persist the refreshed PR state.
+	_ = stack.Save(result.GitDir, result.StackFile)
+
+	// Resolve which branch to operate on.
+	var br *stack.BranchRef
+	if target != "" {
+		_, br, err = resolvePR(result.StackFile, target)
+		if err != nil {
+			cfg.Errorf("%s", err)
+			return nil
+		}
+	} else {
+		idx := s.IndexOf(currentBranch)
+		if idx < 0 {
+			if s.IsFullyMerged() {
+				cfg.Successf("All PRs in this stack have already been merged")
+				return nil
+			}
+			cfg.Errorf("current branch %q is not a stack branch (it may be the trunk)", currentBranch)
+			return nil
+		}
+		br = &s.Branches[idx]
+	}
+
+	if br.PullRequest == nil {
+		cfg.Errorf("no pull request found for branch %q", currentBranch)
+		cfg.Printf("  Run %s to create PRs for this stack.", cfg.ColorCyan("gh stack push"))
+		return nil
+	}
+
+	if br.IsMerged() {
+		cfg.Successf("PR %s has already been merged", cfg.PRLink(br.PullRequest.Number, br.PullRequest.URL))
+		cfg.Printf("  %s", br.PullRequest.URL)
+		return nil
+	}
+
+	prURL := br.PullRequest.URL
+	prLink := cfg.PRLink(br.PullRequest.Number, prURL)
+
+	cfg.Warningf("Merging stacked PRs from the CLI is not yet supported")
+
+	if cfg.IsInteractive() {
+		p := prompter.New(cfg.In, cfg.Out, cfg.Err)
+		openWeb, promptErr := p.Confirm(
+			fmt.Sprintf("Open %s in your browser?", prLink), true)
+		if promptErr != nil {
+			if isInterruptError(promptErr) {
+				printInterrupt(cfg)
+				return nil
+			}
+			cfg.Errorf("prompt failed: %s", promptErr)
+			return nil
+		}
+
+		if openWeb {
+			b := browser.New("", cfg.Out, cfg.Err)
+			if err := b.Browse(prURL); err != nil {
+				cfg.Warningf("failed to open browser: %s", err)
+			} else {
+				cfg.Successf("Opened %s in your browser", prLink)
+				return nil
+			}
+		}
+	}
+
+	cfg.Printf("  You can merge this PR at: %s", prURL)
 	return nil
 }