refactor: split Clone into Clone and MergeAgain

Clone is now a NOP if the PR has not changed, and loses its second
return value, the MergedAgain flag.

MergeAgain must be called explicitly in the only location that
cares about this flag, just before planning.

This cleans up the code for Clone and re-merging a bit.

server/events/github_app_working_dir.go

@@ -19,7 +19,7 @@ type GithubAppWorkingDir struct {
 }
 
 // Clone writes a fresh token for Github App authentication
-func (g *GithubAppWorkingDir) Clone(headRepo models.Repo, p models.PullRequest, workspace string) (string, bool, error) {
+func (g *GithubAppWorkingDir) Clone(headRepo models.Repo, p models.PullRequest, workspace string) (string, error) {
 	baseRepo := &p.BaseRepo
 
 	// Realistically, this is a super brittle way of supporting clones using gh app installation tokens

server/events/github_app_working_dir_test.go

@@ -46,7 +46,7 @@ func TestClone_GithubAppNoneExisting(t *testing.T) {
 		GithubHostname: testServer,
 	}
 
-	cloneDir, _, err := gwd.Clone(models.Repo{}, models.PullRequest{
+	cloneDir, err := gwd.Clone(models.Repo{}, models.PullRequest{
 		BaseRepo:   models.Repo{},
 		HeadBranch: "branch",
 	}, "default")
@@ -89,12 +89,12 @@ func TestClone_GithubAppSetsCorrectUrl(t *testing.T) {
 
 	When(credentials.GetToken()).ThenReturn("token", nil)
 	When(workingDir.Clone(modifiedBaseRepo, models.PullRequest{BaseRepo: modifiedBaseRepo}, "default")).ThenReturn(
-		"", true, nil,
+		"", nil,
 	)
 
-	_, success, _ := ghAppWorkingDir.Clone(headRepo, models.PullRequest{BaseRepo: baseRepo}, "default")
+	_, err := ghAppWorkingDir.Clone(headRepo, models.PullRequest{BaseRepo: baseRepo}, "default")
 
 	workingDir.VerifyWasCalledOnce().Clone(modifiedBaseRepo, models.PullRequest{BaseRepo: modifiedBaseRepo}, "default")
 
-	Assert(t, success == true, "clone url mutation error")
+	Ok(t, err)
 }

server/events/post_workflow_hooks_command_runner.go

@@ -66,7 +66,7 @@ func (w *DefaultPostWorkflowHooksCommandRunner) RunPostHooks(
 	log.Debug("got workspace lock")
 	defer unlockFn()
 
-	repoDir, _, err := w.WorkingDir.Clone(headRepo, pull, DefaultWorkspace)
+	repoDir, err := w.WorkingDir.Clone(headRepo, pull, DefaultWorkspace)
 	if err != nil {
 		return err
 	}

server/events/post_workflow_hooks_command_runner_test.go

@@ -125,7 +125,7 @@ func TestRunPostHooks_Clone(t *testing.T) {
 		postWh.GlobalCfg = globalCfg
 
 		When(postWhWorkingDirLocker.TryLock(testdata.GithubRepo.FullName, newPull.Num, events.DefaultWorkspace, events.DefaultRepoRelDir)).ThenReturn(unlockFn, nil)
-		When(postWhWorkingDir.Clone(testdata.GithubRepo, newPull, events.DefaultWorkspace)).ThenReturn(repoDir, false, nil)
+		When(postWhWorkingDir.Clone(testdata.GithubRepo, newPull, events.DefaultWorkspace)).ThenReturn(repoDir, nil)
 		When(whPostWorkflowHookRunner.Run(Any[models.WorkflowHookCommandContext](), Eq(testHook.RunCommand), Any[string](),
 			Any[string](), Eq(repoDir))).ThenReturn(result, runtimeDesc, nil)
 
@@ -214,7 +214,7 @@ func TestRunPostHooks_Clone(t *testing.T) {
 		postWh.GlobalCfg = globalCfg
 
 		When(postWhWorkingDirLocker.TryLock(testdata.GithubRepo.FullName, newPull.Num, events.DefaultWorkspace, events.DefaultRepoRelDir)).ThenReturn(unlockFn, nil)
-		When(postWhWorkingDir.Clone(testdata.GithubRepo, newPull, events.DefaultWorkspace)).ThenReturn(repoDir, false, errors.New("some error"))
+		When(postWhWorkingDir.Clone(testdata.GithubRepo, newPull, events.DefaultWorkspace)).ThenReturn(repoDir, errors.New("some error"))
 
 		err := postWh.RunPostHooks(ctx, cmd)
 
@@ -247,7 +247,7 @@ func TestRunPostHooks_Clone(t *testing.T) {
 		postWh.GlobalCfg = globalCfg
 
 		When(postWhWorkingDirLocker.TryLock(testdata.GithubRepo.FullName, newPull.Num, events.DefaultWorkspace, events.DefaultRepoRelDir)).ThenReturn(unlockFn, nil)
-		When(postWhWorkingDir.Clone(testdata.GithubRepo, newPull, events.DefaultWorkspace)).ThenReturn(repoDir, false, nil)
+		When(postWhWorkingDir.Clone(testdata.GithubRepo, newPull, events.DefaultWorkspace)).ThenReturn(repoDir, nil)
 		When(whPostWorkflowHookRunner.Run(Any[models.WorkflowHookCommandContext](), Eq(testHook.RunCommand),
 			Any[string](), Any[string](), Eq(repoDir))).ThenReturn(result, runtimeDesc, errors.New("some error"))
 
@@ -287,7 +287,7 @@ func TestRunPostHooks_Clone(t *testing.T) {
 		postWh.GlobalCfg = globalCfg
 
 		When(postWhWorkingDirLocker.TryLock(testdata.GithubRepo.FullName, newPull.Num, events.DefaultWorkspace, events.DefaultRepoRelDir)).ThenReturn(unlockFn, nil)
-		When(postWhWorkingDir.Clone(testdata.GithubRepo, newPull, events.DefaultWorkspace)).ThenReturn(repoDir, false, nil)
+		When(postWhWorkingDir.Clone(testdata.GithubRepo, newPull, events.DefaultWorkspace)).ThenReturn(repoDir, nil)
 		When(whPostWorkflowHookRunner.Run(Any[models.WorkflowHookCommandContext](), Eq(testHook.RunCommand),
 			Any[string](), Any[string](), Eq(repoDir))).ThenReturn(result, runtimeDesc, nil)
 
@@ -321,7 +321,7 @@ func TestRunPostHooks_Clone(t *testing.T) {
 		postWh.GlobalCfg = globalCfg
 
 		When(postWhWorkingDirLocker.TryLock(testdata.GithubRepo.FullName, newPull.Num, events.DefaultWorkspace, events.DefaultRepoRelDir)).ThenReturn(unlockFn, nil)
-		When(postWhWorkingDir.Clone(testdata.GithubRepo, newPull, events.DefaultWorkspace)).ThenReturn(repoDir, false, nil)
+		When(postWhWorkingDir.Clone(testdata.GithubRepo, newPull, events.DefaultWorkspace)).ThenReturn(repoDir, nil)
 		When(whPostWorkflowHookRunner.Run(Any[models.WorkflowHookCommandContext](), Eq(testHookWithShell.RunCommand),
 			Any[string](), Any[string](), Eq(repoDir))).ThenReturn(result, runtimeDesc, nil)
 
@@ -355,7 +355,7 @@ func TestRunPostHooks_Clone(t *testing.T) {
 		postWh.GlobalCfg = globalCfg
 
 		When(postWhWorkingDirLocker.TryLock(testdata.GithubRepo.FullName, newPull.Num, events.DefaultWorkspace, events.DefaultRepoRelDir)).ThenReturn(unlockFn, nil)
-		When(postWhWorkingDir.Clone(testdata.GithubRepo, newPull, events.DefaultWorkspace)).ThenReturn(repoDir, false, nil)
+		When(postWhWorkingDir.Clone(testdata.GithubRepo, newPull, events.DefaultWorkspace)).ThenReturn(repoDir, nil)
 		When(whPostWorkflowHookRunner.Run(Any[models.WorkflowHookCommandContext](), Eq(testHook.RunCommand),
 			Any[string](), Any[string](), Eq(repoDir))).ThenReturn(result, runtimeDesc, nil)
 
@@ -389,7 +389,7 @@ func TestRunPostHooks_Clone(t *testing.T) {
 		postWh.GlobalCfg = globalCfg
 
 		When(postWhWorkingDirLocker.TryLock(testdata.GithubRepo.FullName, newPull.Num, events.DefaultWorkspace, events.DefaultRepoRelDir)).ThenReturn(unlockFn, nil)
-		When(postWhWorkingDir.Clone(testdata.GithubRepo, newPull, events.DefaultWorkspace)).ThenReturn(repoDir, false, nil)
+		When(postWhWorkingDir.Clone(testdata.GithubRepo, newPull, events.DefaultWorkspace)).ThenReturn(repoDir, nil)
 		When(whPostWorkflowHookRunner.Run(Any[models.WorkflowHookCommandContext](),
 			Eq(testHookWithShellandShellArgs.RunCommand), Any[string](), Any[string](), Eq(repoDir))).ThenReturn(result, runtimeDesc, nil)
 

server/events/pre_workflow_hooks_command_runner.go

@@ -64,7 +64,7 @@ func (w *DefaultPreWorkflowHooksCommandRunner) RunPreHooks(ctx *command.Context,
 	log.Debug("got workspace lock")
 	defer unlockFn()
 
-	repoDir, _, err := w.WorkingDir.Clone(headRepo, pull, DefaultWorkspace)
+	repoDir, err := w.WorkingDir.Clone(headRepo, pull, DefaultWorkspace)
 	if err != nil {
 		return err
 	}