fix: session dialog highlight doubling, row overflow, and resize flicker

- DrawLog: invalidate cached bottom rows when selection-highlight
  escapes are present so VS Code's terminal doesn't leave stale
  background colors on the previous cursor row
- session dialog: hard-clamp row text to terminal width so long
  session summaries don't soft-wrap into adjacent rows
- Resize: clear scrollback alongside screen so stale wider content
  doesn't bleed through when the terminal is narrowed

commit: facc7090604d99d817f4154f89cb2d5b969ca37e
author: patriceckhart · 5mo ago · 2026-05-09 20:55 UTC
parent: 9f0629b
signature: unsigned

2 files · +52 -9

M internal/agent/modes/session_dialog.go +17 -8


@@ -172,7 +172,9 @@ func clampViewTop(viewTop, cursor, window, total int) int {
172	172
173	173		// formatSessionRowPlain returns the session row body without any ANSI
174	174		// styling so the caller can wrap it in either a plain mute color or a
175		-	// full-row selection highlight.
	175	+	// full-row selection highlight. The returned string is guaranteed to
	176	+	// fit within maxWidth visible characters so the terminal never soft-
	177	+	// wraps it into the next row.
176	178		func formatSessionRowPlain(s core.SessionSummary, maxWidth int) string {
177	179		when := formatRelative(s.Started)
178	180		summary := strings.TrimSpace(s.Title)

@@ -182,17 +184,24 @@ func formatSessionRowPlain(s core.SessionSummary, maxWidth int) string {
182	184		if summary == "" {
183	185		summary = "(empty)"
184	186		}
	187	+	summary = strings.ReplaceAll(summary, "\n", " ")
185	188		left := fmt.Sprintf("%-14s %s/%s %d msgs $%.4f ",
186	189		when, s.Provider, s.Model, s.MessageCount, s.TotalCost)
187		-	room := maxWidth - len(left)
188		-	if room < 10 {
189		-	room = 10
	190	+	room := maxWidth - len([]rune(left))
	191	+	if room < 4 {
	192	+	room = 4
190	193		}
191		-	if len(summary) > room {
192		-	summary = summary[:room-1] + "…"
	194	+	runes := []rune(summary)
	195	+	if len(runes) > room {
	196	+	summary = string(runes[:room-1]) + "…"
193	197		}
194		-	summary = strings.ReplaceAll(summary, "\n", " ")
195		-	return left + summary
	198	+	row := left + summary
	199	+	// Hard clamp: ensure the full row never exceeds maxWidth.
	200	+	rowRunes := []rune(row)
	201	+	if len(rowRunes) > maxWidth {
	202	+	row = string(rowRunes[:maxWidth-1]) + "…"
	203	+	}
	204	+	return row
196	205		}
197	206
198	207		func formatRelative(t time.Time) string {

 // formatSessionRowPlain returns the session row body without any ANSI
 // styling so the caller can wrap it in either a plain mute color or a
-// full-row selection highlight.
+// full-row selection highlight. The returned string is guaranteed to
+// fit within maxWidth visible characters so the terminal never soft-
+// wraps it into the next row.
 func formatSessionRowPlain(s core.SessionSummary, maxWidth int) string {
 	when := formatRelative(s.Started)
 	summary := strings.TrimSpace(s.Title)
 	if summary == "" {
 		summary = "(empty)"
 	}
+	summary = strings.ReplaceAll(summary, "\n", " ")
 	left := fmt.Sprintf("%-14s  %s/%s  %d msgs  $%.4f  ",
 		when, s.Provider, s.Model, s.MessageCount, s.TotalCost)
-	room := maxWidth - len(left)
+	room := maxWidth - len([]rune(left))
-	if room < 10 {
+	if room < 4 {
-		room = 10
+		room = 4
 	}
-	if len(summary) > room {
+	runes := []rune(summary)
-		summary = summary[:room-1] + "…"
+	if len(runes) > room {
+		summary = string(runes[:room-1]) + "…"
 	}
-	summary = strings.ReplaceAll(summary, "\n", " ")
+	row := left + summary
-	return left + summary
+	// Hard clamp: ensure the full row never exceeds maxWidth.
+	rowRunes := []rune(row)
+	if len(rowRunes) > maxWidth {
+		row = string(rowRunes[:maxWidth-1]) + "…"
+	}
+	return row
 }
 func formatRelative(t time.Time) string {

M internal/tui/render.go +35 -1


@@ -70,7 +70,10 @@ func (r *Renderer) Resize(cols, rows int) {
70	70		r.logHardwareRow = 0
71	71		r.logInit = false
72	72		if r.out != nil {
73		-	_, _ = io.WriteString(r.out, SeqClearScreen)
	73	+	// Clear both screen and scrollback so stale content from
	74	+	// the old width doesn't bleed through. Move to (1,1) so
	75	+	// the next DrawLog/writeFull starts from a clean slate.
	76	+	_, _ = io.WriteString(r.out, SeqDeleteKittyImages+SeqClearScreen+SeqClearScrollback+MoveTo(1, 1))
74	77		}
75	78		}
76	79		}

@@ -395,6 +398,37 @@ func (r *Renderer) DrawLog(chat, bottom []string, cursorBottomRow, cursorCol int
395	398		w.WriteString(SeqShowCursor)
396	399		}
397	400
	401	+	// Selection-highlight workaround: VS Code's terminal (and some
	402	+	// others) don't reliably clear background colors when a row is
	403	+	// overwritten. When the current OR previous bottom block contains
	404	+	// selection-highlight escapes (dialogs with a cursor row), wipe
	405	+	// the cached bottom rows so the diff rewrites every one of them.
	406	+	// This mirrors the hasSelection guard in Draw().
	407	+	if r.logInit && len(r.logLines) > 0 {
	408	+	botHasHL := func(block []string) bool {
	409	+	for _, l := range block {
	410	+	if strings.Contains(l, "\x1b[48;5;") {
	411	+	return true
	412	+	}
	413	+	}
	414	+	return false
	415	+	}
	416	+	if botHasHL(bottomFrame) \|\| botHasHL(r.logBottom) {
	417	+	// Invalidate only the bottom portion of the cached lines
	418	+	// so the chat region (terminal scrollback) is still
	419	+	// diffed cheaply. We do this by replacing the old bottom
	420	+	// rows with empty strings so every bottom row looks
	421	+	// "changed" to the diff below.
	422	+	botStart := len(r.logLines) - len(r.logBottom) - bottomMarginRows
	423	+	if botStart < 0 {
	424	+	botStart = 0
	425	+	}
	426	+	for idx := botStart; idx < len(r.logLines); idx++ {
	427	+	r.logLines[idx] = "\x00" // sentinel that won't match any real line
	428	+	}
	429	+	}
	430	+	}
	431	+
398	432		full := !r.logInit \|\| len(r.logLines) == 0
399	433		if full {
400	434		writeFull(true)


@@ -70,7 +70,10 @@ func (r *Renderer) Resize(cols, rows int) {
70		r.logHardwareRow = 0	70		r.logHardwareRow = 0
71		r.logInit = false	71		r.logInit = false
72		if r.out != nil {	72		if r.out != nil {
73	-	_, _ = io.WriteString(r.out, SeqClearScreen)	73	+	// Clear both screen and scrollback so stale content from
			74	+	// the old width doesn't bleed through. Move to (1,1) so
			75	+	// the next DrawLog/writeFull starts from a clean slate.
			76	+	_, _ = io.WriteString(r.out, SeqDeleteKittyImages+SeqClearScreen+SeqClearScrollback+MoveTo(1, 1))
74		}	77		}
75		}	78		}
76		}	79		}

@@ -395,6 +398,37 @@ func (r *Renderer) DrawLog(chat, bottom []string, cursorBottomRow, cursorCol int
395		w.WriteString(SeqShowCursor)	398		w.WriteString(SeqShowCursor)
396		}	399		}
397			400
			401	+	// Selection-highlight workaround: VS Code's terminal (and some
			402	+	// others) don't reliably clear background colors when a row is
			403	+	// overwritten. When the current OR previous bottom block contains
			404	+	// selection-highlight escapes (dialogs with a cursor row), wipe
			405	+	// the cached bottom rows so the diff rewrites every one of them.
			406	+	// This mirrors the hasSelection guard in Draw().
			407	+	if r.logInit && len(r.logLines) > 0 {
			408	+	botHasHL := func(block []string) bool {
			409	+	for _, l := range block {
			410	+	if strings.Contains(l, "\x1b[48;5;") {
			411	+	return true
			412	+	}
			413	+	}
			414	+	return false
			415	+	}
			416	+	if botHasHL(bottomFrame) \|\| botHasHL(r.logBottom) {
			417	+	// Invalidate only the bottom portion of the cached lines
			418	+	// so the chat region (terminal scrollback) is still
			419	+	// diffed cheaply. We do this by replacing the old bottom
			420	+	// rows with empty strings so every bottom row looks
			421	+	// "changed" to the diff below.
			422	+	botStart := len(r.logLines) - len(r.logBottom) - bottomMarginRows
			423	+	if botStart < 0 {
			424	+	botStart = 0
			425	+	}
			426	+	for idx := botStart; idx < len(r.logLines); idx++ {
			427	+	r.logLines[idx] = "\x00" // sentinel that won't match any real line
			428	+	}
			429	+	}
			430	+	}
			431	+
398		full := !r.logInit \|\| len(r.logLines) == 0	432		full := !r.logInit \|\| len(r.logLines) == 0
399		if full {	433		if full {
400		writeFull(true)	434		writeFull(true)