fix: safer re-merging with updated upstream

server/events/markdown_renderer_test.go

@@ -191,7 +191,7 @@ $$$
 						LockURL:         "lock-url",
 						RePlanCmd:       "atlantis plan -d path -w workspace",
 						ApplyCmd:        "atlantis apply -d path -w workspace",
-						HasDiverged:     true,
+						MergedAgain:     true,
 					},
 					Workspace:  "workspace",
 					RepoRelDir: "path",
@@ -210,7 +210,7 @@ $$$
 * :repeat: To **plan** this project again, comment:
     * $atlantis plan -d path -w workspace$
 
-:warning: The branch we're merging into is ahead, it is recommended to pull new commits first.
+:twisted_rightwards_arrows: Upstream was modified, a new merge was performed.
 
 ---
 * :fast_forward: To **apply** all unapplied plans from this pull request, comment:
@@ -1974,7 +1974,7 @@ $$$
 						LockURL:         "lock-url",
 						RePlanCmd:       "atlantis plan -d path -w workspace",
 						ApplyCmd:        "atlantis apply -d path -w workspace",
-						HasDiverged:     true,
+						MergedAgain:     true,
 					},
 					Workspace:  "workspace",
 					RepoRelDir: "path",
@@ -1992,7 +1992,7 @@ $$$
 * :repeat: To **plan** this project again, comment:
     * $atlantis plan -d path -w workspace$
 
-:warning: The branch we're merging into is ahead, it is recommended to pull new commits first.
+:twisted_rightwards_arrows: Upstream was modified, a new merge was performed.
 
 ---
 * :fast_forward: To **apply** all unapplied plans from this pull request, comment:

server/events/models/models.go

@@ -361,10 +361,10 @@ type PlanSuccess struct {
 	RePlanCmd string
 	// ApplyCmd is the command that users should run to apply this plan.
 	ApplyCmd string
-	// HasDiverged is true if we're using the checkout merge strategy and the
-	// branch we're merging into has been updated since we cloned and merged
-	// it.
-	HasDiverged bool
+	// MergedAgain is true if we're using the checkout merge strategy and the
+	// branch we're merging into had been updated, and we had to merge again
+	// before planning
+	MergedAgain bool
 }
 
 type PolicySetResult struct {

server/events/project_command_runner.go

@@ -543,9 +543,9 @@ func (p *DefaultProjectCommandRunner) doPlan(ctx command.ProjectContext) (*model
 	}
 	defer unlockFn()
 
-	p.WorkingDir.SetSafeToReClone()
+	p.WorkingDir.SetCheckForUpstreamChanges()
 	// Clone is idempotent so okay to run even if the repo was already cloned.
-	repoDir, hasDiverged, cloneErr := p.WorkingDir.Clone(ctx.HeadRepo, ctx.Pull, ctx.Workspace)
+	repoDir, mergedAgain, cloneErr := p.WorkingDir.Clone(ctx.HeadRepo, ctx.Pull, ctx.Workspace)
 	if cloneErr != nil {
 		if unlockErr := lockAttempt.UnlockFn(); unlockErr != nil {
 			ctx.Log.Err("error unlocking state after plan error: %v", unlockErr)
@@ -576,7 +576,7 @@ func (p *DefaultProjectCommandRunner) doPlan(ctx command.ProjectContext) (*model
 		TerraformOutput: strings.Join(outputs, "\n"),
 		RePlanCmd:       ctx.RePlanCmd,
 		ApplyCmd:        ctx.ApplyCmd,
-		HasDiverged:     hasDiverged,
+		MergedAgain:     mergedAgain,
 	}, "", nil
 }
 

server/events/templates/merged_again.tmpl

@@ -0,0 +1,5 @@
+{{ define "mergedAgain" -}}
+{{ if .MergedAgain }}
+:twisted_rightwards_arrows: Upstream was modified, a new merge was performed.
+{{ end -}}
+{{ end -}}

server/events/templates/plan_success_unwrapped.tmpl

@@ -16,5 +16,5 @@ This plan was not saved because one or more projects failed and automerge requir
 * :repeat: To **plan** this project again, comment:
     * `{{ .RePlanCmd }}`
 {{ end -}}
-{{ template "diverged" . }}
+{{ template "mergedAgain" . }}
 {{ end -}}

server/events/templates/plan_success_wrapped.tmpl

@@ -20,5 +20,5 @@ This plan was not saved because one or more projects failed and automerge requir
 {{ end -}}
 </details>
 {{ .PlanSummary -}}
-{{ template "diverged" . -}}
+{{ template "mergedAgain" . -}}
 {{ end -}}