chore: remove old and unused code

2026-08-03 13:08:18 +02:00
parent 312b25fd39
commit 4fcc479779
17 changed files with 325 additions and 142 deletions
--- a/README.md
+++ b/README.md
@@ -239,10 +239,8 @@ Configuration is optional TOML. diple checks:

 1. `--config FILE`;
 2. `DIPLE_CONFIG`;
-3. `GH_THREADS_CONFIG` as a migration fallback;
-4. `$XDG_CONFIG_HOME/diple/config.toml`;
-5. the operating-system configuration directory; and
-6. legacy `gh-threads` paths when no diple configuration exists.
+3. `$XDG_CONFIG_HOME/diple/config.toml`; and
+4. the operating-system configuration directory.

 Common default paths:

--- a/ai_tui.go
+++ b/ai_tui.go
@@ -26,14 +26,16 @@ const (
 )

 type aiPreparedMsg struct {
-	preview  AIPreview
-	threadID string
-	err      error
+	generation uint64
+	preview    AIPreview
+	threadID   string
+	err        error
 }

 type aiCompletedMsg struct {
-	result AIResult
-	err    error
+	generation uint64
+	result     AIResult
+	err        error
 }

 type aiStatusMsg struct {
@@ -41,15 +43,24 @@ type aiStatusMsg struct {
 }

 type aiProgressMsg struct {
-	progress AIRunProgress
+	generation uint64
+	progress   AIRunProgress
 }

 type aiProviderTestCompletedMsg struct {
-	model string
-	err   error
+	generation uint64
+	model      string
+	err        error
 }

-type aiAnimationTickMsg time.Time
+type aiAnimationTickMsg struct {
+	generation uint64
+}
+
+func (m *App) nextAIGeneration() uint64 {
+	m.aiGeneration++
+	return m.aiGeneration
+}

 func (m *App) openAIMenu() {
 	if m.screen == prScreen {
@@ -97,6 +108,7 @@ func (m *App) beginAIPrepare(threadID, message string) tea.Cmd {
 	}
 	ctx, cancel := context.WithCancel(context.Background())
 	m.aiCancel = cancel
+	generation := m.nextAIGeneration()
 	controller, details := m.ai, m.details
 	m.aiMode = aiPreparing
 	m.err = nil
@@ -112,9 +124,11 @@ func (m *App) beginAIPrepare(threadID, message string) tea.Cmd {
 	}
 	prepare := func() tea.Msg {
 		preview, err := controller.Prepare(ctx, details, threadID, message)
-		return aiPreparedMsg{preview: preview, threadID: threadID, err: err}
+		return aiPreparedMsg{
+			generation: generation, preview: preview, threadID: threadID, err: err,
+		}
 	}
-	return tea.Batch(prepare, nextAIAnimationTick())
+	return tea.Batch(prepare, nextAIAnimationTick(generation))
 }

 func (m *App) returnFromAIPrepareFailure(threadID string) {
@@ -133,6 +147,7 @@ func (m *App) beginAIRun() tea.Cmd {
 	}
 	ctx, cancel := context.WithCancel(context.Background())
 	m.aiCancel = cancel
+	generation := m.nextAIGeneration()
 	controller, preview := m.ai, m.aiPreview
 	m.aiMode = aiBusy
 	m.aiSpinner = 0
@@ -146,18 +161,21 @@ func (m *App) beginAIRun() tea.Cmd {
 	m.aiEvents = events
 	work := func() tea.Msg {
 		go func() {
+			defer close(events)
 			result, err := controller.RunWithProgress(ctx, preview, func(progress AIRunProgress) {
 				select {
-				case events <- aiProgressMsg{progress: progress}:
+				case events <- aiProgressMsg{generation: generation, progress: progress}:
 				default:
 				}
 			})
-			events <- aiCompletedMsg{result: result, err: err}
-			close(events)
+			select {
+			case events <- aiCompletedMsg{generation: generation, result: result, err: err}:
+			case <-ctx.Done():
+			}
 		}()
 		return <-events
 	}
-	return tea.Batch(work, nextAIAnimationTick())
+	return tea.Batch(work, nextAIAnimationTick(generation))
 }

 func (m *App) beginAIProviderTest() tea.Cmd {
@@ -168,6 +186,7 @@ func (m *App) beginAIProviderTest() tea.Cmd {
 	}
 	ctx, cancel := context.WithCancel(context.Background())
 	m.aiCancel = cancel
+	generation := m.nextAIGeneration()
 	controller := m.ai
 	m.aiMode = aiProviderTestBusy
 	m.aiSpinner = 0
@@ -181,18 +200,23 @@ func (m *App) beginAIProviderTest() tea.Cmd {
 	m.aiEvents = events
 	work := func() tea.Msg {
 		go func() {
+			defer close(events)
 			model, err := controller.TestProvider(ctx, func(progress AIRunProgress) {
 				select {
-				case events <- aiProgressMsg{progress: progress}:
+				case events <- aiProgressMsg{generation: generation, progress: progress}:
 				default:
 				}
 			})
-			events <- aiProviderTestCompletedMsg{model: model, err: err}
-			close(events)
+			select {
+			case events <- aiProviderTestCompletedMsg{
+				generation: generation, model: model, err: err,
+			}:
+			case <-ctx.Done():
+			}
 		}()
 		return <-events
 	}
-	return tea.Batch(work, nextAIAnimationTick())
+	return tea.Batch(work, nextAIAnimationTick(generation))
 }

 func waitAIEvent(events <-chan tea.Msg) tea.Cmd {
@@ -204,9 +228,9 @@ func waitAIEvent(events <-chan tea.Msg) tea.Cmd {
 	}
 }

-func nextAIAnimationTick() tea.Cmd {
-	return tea.Tick(100*time.Millisecond, func(at time.Time) tea.Msg {
-		return aiAnimationTickMsg(at)
+func nextAIAnimationTick(generation uint64) tea.Cmd {
+	return tea.Tick(100*time.Millisecond, func(time.Time) tea.Msg {
+		return aiAnimationTickMsg{generation: generation}
 	})
 }

@@ -215,7 +239,7 @@ func (m App) updateAI(msg tea.Msg) (tea.Model, tea.Cmd, bool) {
 	case tea.WindowSizeMsg:
 		return m, nil, false
 	case aiPreparedMsg:
-		if m.aiMode != aiPreparing {
+		if msg.generation != m.aiGeneration || m.aiMode != aiPreparing {
 			return m, nil, true
 		}
 		m.aiCancel = nil
@@ -230,15 +254,19 @@ func (m App) updateAI(msg tea.Msg) (tea.Model, tea.Cmd, bool) {
 		}
 		return m, nil, true
 	case aiAnimationTickMsg:
+		if msg.generation != m.aiGeneration {
+			return m, nil, true
+		}
 		switch m.aiMode {
 		case aiPreparing, aiBusy, aiProviderTestBusy:
 			m.aiSpinner++
-			return m, nextAIAnimationTick(), true
+			return m, nextAIAnimationTick(msg.generation), true
 		default:
 			return m, nil, true
 		}
 	case aiProgressMsg:
-		if m.aiMode != aiBusy && m.aiMode != aiProviderTestBusy {
+		if msg.generation != m.aiGeneration ||
+			(m.aiMode != aiBusy && m.aiMode != aiProviderTestBusy) {
 			return m, nil, true
 		}
 		m.aiProgress = msg.progress
@@ -247,7 +275,7 @@ func (m App) updateAI(msg tea.Msg) (tea.Model, tea.Cmd, bool) {
 		m.aiStatus, m.aiStatusBusy = msg.status, false
 		return m, nil, true
 	case aiCompletedMsg:
-		if m.aiMode != aiBusy {
+		if msg.generation != m.aiGeneration || m.aiMode != aiBusy {
 			return m, nil, true
 		}
 		m.aiCancel, m.aiEvents = nil, nil
@@ -281,7 +309,7 @@ func (m App) updateAI(msg tea.Msg) (tea.Model, tea.Cmd, bool) {
 		m.recordHealth("AI provider", healthOK, healthMessage)
 		return m, nil, true
 	case aiProviderTestCompletedMsg:
-		if m.aiMode != aiProviderTestBusy {
+		if msg.generation != m.aiGeneration || m.aiMode != aiProviderTestBusy {
 			return m, nil, true
 		}
 		m.aiCancel, m.aiEvents = nil, nil
@@ -322,6 +350,7 @@ func (m App) updateAI(msg tea.Msg) (tea.Model, tea.Cmd, bool) {
 			m.aiCancel()
 			m.aiCancel = nil
 		}
+		m.nextAIGeneration()
 		m.aiMode, m.aiInput, m.writeThreadID, m.aiEvents = aiNone, "", "", nil
 		m.aiInputEditor = textEditor{}
 		return m, nil, true
--- a/cli.go
+++ b/cli.go
@@ -108,8 +108,7 @@ Other:

 Boolean options accept explicit values, for example --cache=false.
 Command-line options override TOML settings. GH_REPO is used only when
--repo is absent. DIPLE_CONFIG selects a configuration file; GH_THREADS_CONFIG
-is retained as a migration fallback.
+--repo is absent. DIPLE_CONFIG selects a configuration file.

 Authentication uses GH_TOKEN or GITHUB_TOKEN when set, otherwise the active
 credential from 'gh auth login'. Run 'diple completion --help' for completion
--- a/config.go
+++ b/config.go
@@ -137,16 +137,8 @@ func configPath() (string, error) {
 	if path := os.Getenv("DIPLE_CONFIG"); path != "" {
 		return path, nil
 	}
-	// Preserve the old override during the rename so existing scripts do not
-	// silently start with a fresh configuration.
-	if path := os.Getenv("GH_THREADS_CONFIG"); path != "" {
-		return path, nil
-	}
 	if base := os.Getenv("XDG_CONFIG_HOME"); base != "" {
-		return firstExistingOrDefault(
-			filepath.Join(base, "diple", "config.toml"),
-			filepath.Join(base, "gh-threads", "config.toml"),
-		), nil
+		return filepath.Join(base, "diple", "config.toml"), nil
 	}
 	base, err := os.UserConfigDir()
 	if err != nil {
@@ -158,19 +150,11 @@ func configPath() (string, error) {
 		return "", fmt.Errorf("find home directory: %w", err)
 	}
 	dotConfig := filepath.Join(home, ".config", "diple", "config.toml")
-	legacyPreferred := filepath.Join(base, "gh-threads", "config.toml")
-	legacyDotConfig := filepath.Join(home, ".config", "gh-threads", "config.toml")
-	return firstExistingOrDefault(
-		preferred, dotConfig, legacyPreferred, legacyDotConfig,
-	), nil
+	return existingConfigPath(preferred, dotConfig), nil
 }

 func existingConfigPath(preferred, fallback string) string {
-	return firstExistingOrDefault(preferred, fallback)
-}
-
-func firstExistingOrDefault(preferred string, alternatives ...string) string {
-	for _, candidate := range append([]string{preferred}, alternatives...) {
+	for _, candidate := range []string{preferred, fallback} {
 		if _, err := os.Stat(candidate); err == nil || !errors.Is(err, os.ErrNotExist) {
 			return candidate
 		}
@@ -259,10 +243,7 @@ func defaultCacheDir() (string, error) {
 	if err != nil {
 		return "", fmt.Errorf("find user cache directory: %w", err)
 	}
-	return firstExistingOrDefault(
-		filepath.Join(base, "diple"),
-		filepath.Join(base, "gh-threads"),
-	), nil
+	return filepath.Join(base, "diple"), nil
 }

 func validateThreadStatusOrder(order []string) error {
--- a/config_test.go
+++ b/config_test.go
@@ -233,7 +233,6 @@ func TestLoadConfigRejectsUnknownSettings(t *testing.T) {

 func TestConfigPathHonorsEnvironmentOverride(t *testing.T) {
 	t.Setenv("DIPLE_CONFIG", "/tmp/custom-diple.toml")
-	t.Setenv("GH_THREADS_CONFIG", "")
 	got, err := configPath()
 	if err != nil {
 		t.Fatal(err)
@@ -243,18 +242,6 @@ func TestConfigPathHonorsEnvironmentOverride(t *testing.T) {
 	}
 }

-func TestConfigPathHonorsLegacyEnvironmentOverride(t *testing.T) {
-	t.Setenv("DIPLE_CONFIG", "")
-	t.Setenv("GH_THREADS_CONFIG", "/tmp/legacy-gh-threads.toml")
-	got, err := configPath()
-	if err != nil {
-		t.Fatal(err)
-	}
-	if got != "/tmp/legacy-gh-threads.toml" {
-		t.Fatalf("legacy config path = %q", got)
-	}
-}
-
 func TestExistingConfigPathFallsBackToDotConfig(t *testing.T) {
 	root := t.TempDir()
 	preferred := filepath.Join(root, "Library", "Application Support", "diple", "config.toml")
@@ -280,23 +267,7 @@ func TestExistingConfigPathFallsBackToDotConfig(t *testing.T) {
 	}
 }

-func TestFirstExistingConfigPathFallsBackToLegacyName(t *testing.T) {
-	root := t.TempDir()
-	current := filepath.Join(root, "diple", "config.toml")
-	legacy := filepath.Join(root, "gh-threads", "config.toml")
-	if err := os.MkdirAll(filepath.Dir(legacy), 0o700); err != nil {
-		t.Fatal(err)
-	}
-	if err := os.WriteFile(legacy, []byte("theme = \"dark\"\n"), 0o600); err != nil {
-		t.Fatal(err)
-	}
-	if got := firstExistingOrDefault(current, legacy); got != legacy {
-		t.Fatalf("migration config path = %q, want %q", got, legacy)
-	}
-}
-
 func TestConfigPathHonorsXDGConfigHome(t *testing.T) {
-	t.Setenv("GH_THREADS_CONFIG", "")
 	t.Setenv("DIPLE_CONFIG", "")
 	t.Setenv("XDG_CONFIG_HOME", "/tmp/xdg-config")
 	got, err := configPath()
--- a/github.go
+++ b/github.go
@@ -1093,16 +1093,6 @@ func (c *GitHubClient) allCheckContexts(
 	return nodes, nil
 }

-func checkMayHaveUsefulAnnotations(check githubCheckContext) bool {
-	state := strings.ToUpper(firstNonEmpty(check.Conclusion, check.State, check.Status))
-	switch state {
-	case "FAILURE", "ERROR", "CANCELLED", "TIMED_OUT", "ACTION_REQUIRED", "STALE":
-		return true
-	default:
-		return false
-	}
-}
-
 func (c *GitHubClient) checkAnnotations(
 	ctx context.Context, checkID string,
 ) ([]githubCheckAnnotation, error) {
@@ -1427,6 +1417,17 @@ func (c *GitHubClient) EnrichPullRequest(
 		Owner: details.Owner, Repository: details.Repository, Number: details.Number,
 		HeadOID: details.HeadOID, CheckAnnotations: make(map[string][]CheckAnnotation),
 	}
+	type annotationJob struct {
+		index int
+		check Check
+	}
+	type annotationResult struct {
+		checkID     string
+		annotations []CheckAnnotation
+		err         error
+	}
+	var jobs []annotationJob
+	var annotations []annotationResult
 	for _, check := range details.Checks {
 		if check.ID == "" || !checkStateMayHaveUsefulAnnotations(check) {
 			continue
@@ -1435,37 +1436,69 @@ func (c *GitHubClient) EnrichPullRequest(
 			result.CheckAnnotations[check.ID] = annotations
 			continue
 		}
-		nodes, err := c.checkAnnotations(ctx, check.ID)
-		if err != nil {
-			result.Issues = append(result.Issues, DataIssue{
-				Component: "check annotations", Message: err.Error(),
-			})
-			continue
-		}
-		annotations := make([]CheckAnnotation, 0, len(nodes))
-		for _, annotation := range nodes {
-			annotations = append(annotations, CheckAnnotation{
-				Path: annotation.Path, StartLine: annotation.Location.Start.Line,
-				EndLine: annotation.Location.End.Line, Level: annotation.AnnotationLevel,
-				Title: annotation.Title, Message: annotation.Message,
-			})
-		}
-		c.storeAnnotations(check.ID, annotations)
-		result.CheckAnnotations[check.ID] = annotations
+		jobs = append(jobs, annotationJob{index: len(annotations), check: check})
+		annotations = append(annotations, annotationResult{checkID: check.ID})
 	}
+
+	var wait sync.WaitGroup
+	queue := make(chan annotationJob, len(jobs))
+	for _, job := range jobs {
+		queue <- job
+	}
+	close(queue)
+	for range min(4, len(jobs)) {
+		wait.Add(1)
+		go func() {
+			defer wait.Done()
+			for job := range queue {
+				nodes, err := c.checkAnnotations(ctx, job.check.ID)
+				if err != nil {
+					annotations[job.index].err = err
+					continue
+				}
+				converted := make([]CheckAnnotation, 0, len(nodes))
+				for _, annotation := range nodes {
+					converted = append(converted, CheckAnnotation{
+						Path: annotation.Path, StartLine: annotation.Location.Start.Line,
+						EndLine: annotation.Location.End.Line, Level: annotation.AnnotationLevel,
+						Title: annotation.Title, Message: annotation.Message,
+					})
+				}
+				c.storeAnnotations(job.check.ID, converted)
+				annotations[job.index].annotations = converted
+			}
+		}()
+	}
+
+	var conflictFiles []string
+	var conflictErr error
 	if details.Mergeable == "CONFLICTING" && c.conflicts != nil {
-		files, err := c.loadConflictFiles(
-			ctx, details.RepositoryURL, details.Number, details.BaseRef,
-			details.BaseOID, details.HeadOID,
-		)
-		if err != nil {
+		wait.Add(1)
+		go func() {
+			defer wait.Done()
+			conflictFiles, conflictErr = c.loadConflictFiles(
+				ctx, details.RepositoryURL, details.Number, details.BaseRef,
+				details.BaseOID, details.HeadOID,
+			)
+		}()
+	}
+	wait.Wait()
+	for _, loaded := range annotations {
+		if loaded.err != nil {
 			result.Issues = append(result.Issues, DataIssue{
-				Component: "conflict file scan", Message: err.Error(),
+				Component: "check annotations", Message: loaded.err.Error(),
 			})
 		} else {
-			result.ConflictFiles = files
+			result.CheckAnnotations[loaded.checkID] = loaded.annotations
 		}
 	}
+	if conflictErr != nil {
+		result.Issues = append(result.Issues, DataIssue{
+			Component: "conflict file scan", Message: conflictErr.Error(),
+		})
+	} else if conflictFiles != nil {
+		result.ConflictFiles = conflictFiles
+	}
 	level, summary := healthOK, "secondary PR data loaded"
 	if len(result.Issues) > 0 {
 		level, summary = healthWarning, fmt.Sprintf(
--- a/github_test.go
+++ b/github_test.go
@@ -3,11 +3,13 @@ package main
 import (
 	"context"
 	"encoding/json"
+	"fmt"
 	"net/http"
 	"net/http/httptest"
 	"reflect"
 	"strconv"
 	"strings"
+	"sync/atomic"
 	"testing"
 	"time"
 )
@@ -406,6 +408,44 @@ func TestCheckContextsAndAnnotationsArePaginated(t *testing.T) {
 	}
 }

+func TestPullRequestEnrichmentBoundsConcurrentAnnotationRequests(t *testing.T) {
+	var active, maximum atomic.Int32
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		var request graphQLRequest
+		if err := json.NewDecoder(r.Body).Decode(&request); err != nil {
+			t.Error(err)
+			return
+		}
+		current := active.Add(1)
+		defer active.Add(-1)
+		for observed := maximum.Load(); current > observed; observed = maximum.Load() {
+			if maximum.CompareAndSwap(observed, current) {
+				break
+			}
+		}
+		time.Sleep(20 * time.Millisecond)
+		_, _ = w.Write([]byte(`{"data":{"node":{"annotations":{
+			"pageInfo":{"hasNextPage":false},"nodes":[]
+		}}}}`))
+	}))
+	defer server.Close()
+
+	client := NewGitHubClient(server.URL, "secret")
+	details := PRDetails{}
+	for index := range 6 {
+		details.Checks = append(details.Checks, Check{
+			ID: fmt.Sprintf("check-%d", index), Conclusion: "FAILURE",
+		})
+	}
+	result := client.EnrichPullRequest(context.Background(), details)
+	if len(result.CheckAnnotations) != len(details.Checks) || len(result.Issues) != 0 {
+		t.Fatalf("enrichment = %#v", result)
+	}
+	if got := maximum.Load(); got < 2 || got > 4 {
+		t.Fatalf("maximum concurrent annotation requests = %d, want 2..4", got)
+	}
+}
+
 func TestCheckQueriesUseCurrentGitHubSchemaShape(t *testing.T) {
 	for name, query := range map[string]string{"annotations": checkAnnotationsPageQuery} {
 		if strings.Contains(query, "output {") ||
--- a/go.mod
+++ b/go.mod
@@ -9,6 +9,8 @@ require (
 	github.com/charmbracelet/glamour v1.0.0
 	github.com/charmbracelet/lipgloss v1.1.1-0.20250404203927-76690c660834
 	github.com/charmbracelet/x/ansi v0.10.2
+	github.com/muesli/termenv v0.16.0
+	github.com/rivo/uniseg v0.4.7
 )

 require (
@@ -29,8 +31,6 @@ require (
 	github.com/muesli/ansi v0.0.0-20230316100256-276c6243b2f6 // indirect
 	github.com/muesli/cancelreader v0.2.2 // indirect
 	github.com/muesli/reflow v0.3.0 // indirect
-	github.com/muesli/termenv v0.16.0 // indirect
-	github.com/rivo/uniseg v0.4.7 // indirect
 	github.com/xo/terminfo v0.0.0-20220910002029-abceb7e1c41e // indirect
 	github.com/yuin/goldmark v1.7.13 // indirect
 	github.com/yuin/goldmark-emoji v1.0.6 // indirect
--- a/highlight.go
+++ b/highlight.go
@@ -6,18 +6,67 @@ import (
 	"regexp"
 	"strconv"
 	"strings"
+	"sync"

 	"github.com/alecthomas/chroma/v2/lexers"
 	"github.com/alecthomas/chroma/v2/quick"
 )

 const reviewContextLines = 3
+const highlightedDiffCacheLimit = 256

 var codeHighlightTheme = "github-dark"
 var colorEnabled = true

 var hunkHeaderPattern = regexp.MustCompile(`^@@ -(\d+)(?:,\d+)? \+(\d+)(?:,\d+)? @@`)

+type highlightedDiffCacheKey struct {
+	path, hunk, side, theme string
+	startLine, endLine      int
+	color                   bool
+}
+
+type highlightedDiffCache struct {
+	mu      sync.Mutex
+	entries map[highlightedDiffCacheKey][]highlightedDiffLine
+	order   []highlightedDiffCacheKey
+}
+
+var highlightedDiffs = highlightedDiffCache{
+	entries: make(map[highlightedDiffCacheKey][]highlightedDiffLine),
+}
+
+func (c *highlightedDiffCache) get(key highlightedDiffCacheKey) ([]highlightedDiffLine, bool) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	lines, ok := c.entries[key]
+	return append([]highlightedDiffLine(nil), lines...), ok
+}
+
+func (c *highlightedDiffCache) put(
+	key highlightedDiffCacheKey, lines []highlightedDiffLine,
+) []highlightedDiffLine {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	if cached, ok := c.entries[key]; ok {
+		return append([]highlightedDiffLine(nil), cached...)
+	}
+	if len(c.entries) >= highlightedDiffCacheLimit {
+		delete(c.entries, c.order[0])
+		c.order = c.order[1:]
+	}
+	c.entries[key] = append([]highlightedDiffLine(nil), lines...)
+	c.order = append(c.order, key)
+	return append([]highlightedDiffLine(nil), lines...)
+}
+
+func (c *highlightedDiffCache) clear() {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	c.entries = make(map[highlightedDiffCacheKey][]highlightedDiffLine)
+	c.order = nil
+}
+
 type highlightedDiffLine struct {
 	gutter   string
 	code     string
@@ -34,6 +83,17 @@ type parsedDiffLine struct {
 }

 func highlightDiff(path, hunk string, startLine, endLine int, side string) []highlightedDiffLine {
+	key := highlightedDiffCacheKey{
+		path: path, hunk: hunk, side: side, theme: codeHighlightTheme,
+		startLine: startLine, endLine: endLine, color: colorEnabled,
+	}
+	if cached, ok := highlightedDiffs.get(key); ok {
+		return cached
+	}
+	return highlightedDiffs.put(key, highlightDiffUncached(path, hunk, startLine, endLine, side))
+}
+
+func highlightDiffUncached(path, hunk string, startLine, endLine int, side string) []highlightedDiffLine {
 	if hunk == "" {
 		return []highlightedDiffLine{{code: "(GitHub did not return a diff hunk)"}}
 	}
--- a/highlight_test.go
+++ b/highlight_test.go
@@ -106,3 +106,17 @@ func TestHighlightDiffRemovesOnlyCommonIndent(t *testing.T) {
 		t.Fatalf("dedented code:\n%q\nwant:\n%q", got, want)
 	}
 }
+
+func TestHighlightDiffCacheReturnsIndependentSlices(t *testing.T) {
+	highlightedDiffs.clear()
+
+	first := highlightDiff("main.go", "@@ -1 +1 @@\n-old\n+new", 1, 1, "RIGHT")
+	if len(first) == 0 {
+		t.Fatal("highlighted diff is empty")
+	}
+	first[0].code = "mutated"
+	second := highlightDiff("main.go", "@@ -1 +1 @@\n-old\n+new", 1, 1, "RIGHT")
+	if len(second) == 0 || second[0].code == "mutated" {
+		t.Fatalf("cached highlighted diff shares caller storage: %#v", second)
+	}
+}
--- a/main.go
+++ b/main.go
@@ -63,8 +63,7 @@ func main() {
 	flag.Visit(func(item *flag.Flag) { visited[item.Name] = true })
 	config, err := loadConfig(
 		*configFile,
-		visited["config"] || os.Getenv("DIPLE_CONFIG") != "" ||
-			os.Getenv("GH_THREADS_CONFIG") != "",
+		visited["config"] || os.Getenv("DIPLE_CONFIG") != "",
 	)
 	if err != nil {
 		exitf("configuration: %v", err)
--- a/pr_editor.go
+++ b/pr_editor.go
@@ -28,6 +28,7 @@ func (m *App) startPREdit() tea.Cmd {
 		return nil
 	}
 	m.writeMode = writePREdit
+	m.prEditGeneration++
 	m.prEditField = prEditBodyField
 	modal := m.editorMode == "vim"
 	m.prEditEditors[prEditTitleField] = newTextEditor(m.details.Title, modal)
@@ -71,12 +72,14 @@ func (m *App) loadPREditBranches() tea.Cmd {
 		return nil
 	}
 	m.prEditBranchesLoading = true
-	owner, repo := m.details.Owner, m.details.Repository
+	owner, repo, generation := m.details.Owner, m.details.Repository, m.prEditGeneration
 	return func() tea.Msg {
 		ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
 		defer cancel()
 		branches, err := service.ListBranches(ctx, owner, repo)
-		return branchesLoadedMsg{owner: owner, repo: repo, branches: branches, err: err}
+		return branchesLoadedMsg{
+			generation: generation, owner: owner, repo: repo, branches: branches, err: err,
+		}
 	}
 }

@@ -87,12 +90,14 @@ func (m *App) loadPREditUsers() tea.Cmd {
 		return nil
 	}
 	m.prEditUsersLoading = true
-	owner, repo := m.details.Owner, m.details.Repository
+	owner, repo, generation := m.details.Owner, m.details.Repository, m.prEditGeneration
 	return func() tea.Msg {
 		ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
 		defer cancel()
 		users, err := service.ListRepositoryUsers(ctx, owner, repo)
-		return repositoryUsersLoadedMsg{owner: owner, repo: repo, users: users, err: err}
+		return repositoryUsersLoadedMsg{
+			generation: generation, owner: owner, repo: repo, users: users, err: err,
+		}
 	}
 }

--- a/text_editor.go
+++ b/text_editor.go
@@ -617,10 +617,6 @@ func normalEditorLineLast(value string, cursor, wrapWidth int) int {
 	return start
 }

-func moveNormalCursorLine(value string, cursor, delta int) int {
-	return moveEditorCursorLine(value, cursor, delta, 0, true)
-}
-
 func nextWordStart(value string, cursor int, big bool) int {
 	runes := []rune(value)
 	cursor = clamp(cursor, 0, len(runes))
@@ -666,10 +662,6 @@ func previousWordStart(value string, cursor int, big bool) int {
 	return cursor
 }

-func wordEnd(value string, cursor int, big bool) int {
-	return wordEndAtWidth(value, cursor, big, 0)
-}
-
 func wordEndAtWidth(value string, cursor int, big bool, wrapWidth int) int {
 	runes := []rune(value)
 	cursor = clamp(cursor, 0, len(runes))
--- a/theme.go
+++ b/theme.go
@@ -103,6 +103,7 @@ func applyTheme(name string, custom ...CustomThemeConfig) error {
 	commentMarkdownRenderers.Clear()
 	commentMarkdownLines.clear()
 	renderedSuggestions.clear()
+	highlightedDiffs.clear()
 	return nil
 }

--- a/tui.go
+++ b/tui.go
@@ -102,13 +102,15 @@ type detailsLoadedMsg struct {
 }

 type branchesLoadedMsg struct {
-	owner    string
-	repo     string
-	branches []RepositoryBranch
-	err      error
+	generation uint64
+	owner      string
+	repo       string
+	branches   []RepositoryBranch
+	err        error
 }

 type repositoryUsersLoadedMsg struct {
+	generation  uint64
 	owner, repo string
 	users       []RepositoryUser
 	err         error
@@ -171,6 +173,7 @@ type App struct {
 	prEditUsersLoading    bool
 	prEditUsersError      string
 	prEditUserIndex       int
+	prEditGeneration      uint64
 	cursorOutput          *terminalCursorOutput

 	foldResolved           bool
@@ -209,6 +212,7 @@ type App struct {
 	aiProgress             AIRunProgress
 	aiSpinner              int
 	aiEvents               <-chan tea.Msg
+	aiGeneration           uint64
 	difflet                diffletModel
 	mutations              *mutationQueueStore
 	mutationReplayBusy     bool
@@ -1049,7 +1053,7 @@ func (m App) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 		}
 		return m, tea.Batch(m.startMutationReplay(), m.difflet.setState(diffletSuccess))
 	case branchesLoadedMsg:
-		if m.writeMode != writePREdit ||
+		if msg.generation != m.prEditGeneration || m.writeMode != writePREdit ||
 			msg.owner != m.details.Owner || msg.repo != m.details.Repository {
 			return m, nil
 		}
@@ -1065,7 +1069,7 @@ func (m App) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 		m.prEditBranchIndex = 0
 		m.ensurePREditCursorVisible()
 	case repositoryUsersLoadedMsg:
-		if m.writeMode != writePREdit ||
+		if msg.generation != m.prEditGeneration || m.writeMode != writePREdit ||
 			msg.owner != m.details.Owner || msg.repo != m.details.Repository {
 			return m, nil
 		}
--- a/tui_test.go
+++ b/tui_test.go
@@ -919,6 +919,63 @@ func TestPullRequestAIPreparationFailureIgnoresOldDiscussionThread(t *testing.T)
 	}
 }

+func TestAIStaleOperationMessagesAreIgnored(t *testing.T) {
+	m := NewApp(nil, "o", "r", false, 50, time.Second)
+	m.aiGeneration = 2
+	m.aiMode = aiBusy
+	m.aiProgress = AIRunProgress{Stage: "current run"}
+
+	updated, command, handled := m.updateAI(aiProgressMsg{
+		generation: 1, progress: AIRunProgress{Stage: "stale run"},
+	})
+	m = updated.(App)
+	if !handled || command != nil || m.aiProgress.Stage != "current run" {
+		t.Fatalf("stale progress handled=%v command=%v progress=%q",
+			handled, command, m.aiProgress.Stage)
+	}
+
+	updated, command, handled = m.updateAI(aiCompletedMsg{generation: 1})
+	m = updated.(App)
+	if !handled || command != nil || m.aiMode != aiBusy {
+		t.Fatalf("stale completion handled=%v command=%v mode=%v",
+			handled, command, m.aiMode)
+	}
+
+	m.aiMode = aiPreparing
+	updated, command, handled = m.updateAI(aiPreparedMsg{generation: 1})
+	m = updated.(App)
+	if !handled || command != nil || m.aiMode != aiPreparing {
+		t.Fatalf("stale preparation handled=%v command=%v mode=%v",
+			handled, command, m.aiMode)
+	}
+}
+
+func TestPREditStaleRecommendationMessagesAreIgnored(t *testing.T) {
+	m := NewApp(nil, "o", "r", false, 50, time.Second)
+	m.details = PRDetails{PullRequest: PullRequest{Owner: "o", Repository: "r"}}
+	m.writeMode = writePREdit
+	m.prEditGeneration = 2
+	m.prEditBranches = []RepositoryBranch{{Name: "current"}}
+
+	updated, command := m.Update(branchesLoadedMsg{
+		generation: 1, owner: "o", repo: "r",
+		branches: []RepositoryBranch{{Name: "stale"}},
+	})
+	m = updated.(App)
+	if command != nil || len(m.prEditBranches) != 1 || m.prEditBranches[0].Name != "current" {
+		t.Fatalf("stale branches command=%v branches=%#v", command, m.prEditBranches)
+	}
+
+	updated, command = m.Update(branchesLoadedMsg{
+		generation: 2, owner: "o", repo: "r",
+		branches: []RepositoryBranch{{Name: "accepted"}},
+	})
+	m = updated.(App)
+	if command != nil || len(m.prEditBranches) != 1 || m.prEditBranches[0].Name != "accepted" {
+		t.Fatalf("current branches command=%v branches=%#v", command, m.prEditBranches)
+	}
+}
+
 func TestVimModeUsesGlobalFooterBar(t *testing.T) {
 	m := NewApp(nil, "o", "r", false, 50, time.Second)
 	m.width, m.height = 80, 10
--- a/version.go
+++ b/version.go
@@ -1,3 +1,3 @@
 package main

-const dipleVersion = "0.4.0"
+const dipleVersion = "0.5.0"