251604c fix(tui): preserve scrollback when hiding right bar · zut

M packages/tui/render.go +12 -7


@@ -37,12 +37,13 @@ type Renderer struct {
37	37		// in the terminal's visible viewport so we can diff safely, and bail
38	38		// out to clear+replay when the diff would touch rows that are no
39	39		// longer addressable.
40		-	logChat []string
41		-	logBottom []string
42		-	logLines []string
43		-	logViewportTop int
44		-	logHardwareRow int
45		-	logInit bool
	40	+	logChat []string
	41	+	logBottom []string
	42	+	logLines []string
	43	+	logViewportTop int
	44	+	logHardwareRow int
	45	+	logInit bool
	46	+	logNeedsFullRepaint bool
46	47
47	48		// keepScrollback is true when we must NOT emit \x1b[3J
48	49		// (erase-in-display 3, "clear scrollback").

@@ -588,8 +589,12 @@ func (r *Renderer) DrawLog(chat, bottom []string, cursorBottomRow, cursorCol int
588	589		wasInitialized := r.logInit
589	590		full := !wasInitialized \|\| len(r.logLines) == 0
590	591		if full {
591		-	writeFull(true, !wasInitialized)
	592	+	// Returning from the fixed right-bar frame needs a full viewport
	593	+	// repaint, but it must not discard terminal scrollback merely because
	594	+	// the renderer's flow cache is intentionally empty.
	595	+	writeFull(true, !wasInitialized && !r.logNeedsFullRepaint)
592	596		r.logInit = true
	597	+	r.logNeedsFullRepaint = false
593	598		} else {
594	599		firstChanged := -1
595	600		lastChanged := -1

 	// in the terminal's visible viewport so we can diff safely, and bail
 	// out to clear+replay when the diff would touch rows that are no
 	// longer addressable.
-	logChat        []string
+	logChat             []string
-	logBottom      []string
+	logBottom           []string
-	logLines       []string
+	logLines            []string
-	logViewportTop int
+	logViewportTop      int
-	logHardwareRow int
+	logHardwareRow      int
-	logInit        bool
+	logInit             bool
+	logNeedsFullRepaint bool
 	// keepScrollback is true when we must NOT emit \x1b[3J
 	// (erase-in-display 3, "clear scrollback").
 	wasInitialized := r.logInit
 	full := !wasInitialized || len(r.logLines) == 0
 	if full {
-		writeFull(true, !wasInitialized)
+		// Returning from the fixed right-bar frame needs a full viewport
+		// repaint, but it must not discard terminal scrollback merely because
+		// the renderer's flow cache is intentionally empty.
+		writeFull(true, !wasInitialized && !r.logNeedsFullRepaint)
 		r.logInit = true
+		r.logNeedsFullRepaint = false
 	} else {
 		firstChanged := -1
 		lastChanged := -1

M packages/tui/rightbar.go +3 -1


@@ -401,12 +401,14 @@ func (r *Renderer) DrawRightBar(chat, bottom, rightBar []string, cursorBottomRow
401	401
402	402		// Draw() owns the fixed-frame cache. Reset the flow-mode cache so a
403	403		// later fallback to DrawLog starts with a full repaint instead of trying
404		-	// to diff against logical rows from before the rail was enabled.
	404	+	// to diff against logical rows from before the rail was enabled. Mark the
	405	+	// transition separately so that repaint does not clear scrollback.
405	406		r.logChat = nil
406	407		r.logBottom = nil
407	408		r.logLines = nil
408	409		r.logViewportTop = 0
409	410		r.logHardwareRow = 0
410	411		r.logInit = false
	412	+	r.logNeedsFullRepaint = true
411	413		r.Draw(frame, cursorRow, cursorCol)
412	414		}

 	// Draw() owns the fixed-frame cache. Reset the flow-mode cache so a
 	// later fallback to DrawLog starts with a full repaint instead of trying
-	// to diff against logical rows from before the rail was enabled.
+	// to diff against logical rows from before the rail was enabled. Mark the
+	// transition separately so that repaint does not clear scrollback.
 	r.logChat = nil
 	r.logBottom = nil
 	r.logLines = nil
 	r.logViewportTop = 0
 	r.logHardwareRow = 0
 	r.logInit = false
+	r.logNeedsFullRepaint = true
 	r.Draw(frame, cursorRow, cursorCol)
 }

M packages/tui/rightbar_test.go +25 -0


@@ -184,6 +184,31 @@ func TestJoinRightBarPreservesCellBudgetForUnicode(t *testing.T) {
184	184		}
185	185		}
186	186
	187	+	func TestRendererDrawRightBarToDrawLogKeepsScrollback(t *testing.T) {
	188	+	t.Setenv("TERM_PROGRAM", "")
	189	+
	190	+	var out bytes.Buffer
	191	+	r := NewRenderer(&out)
	192	+	r.SetTheme(Dark)
	193	+	r.Resize(80, 5)
	194	+	r.DrawRightBar(
	195	+	[]string{"chat"},
	196	+	[]string{"input"},
	197	+	RenderRightBar(Dark, []RightBarWidget{{Extension: "plan", Title: "Plan", Lines: []string{"task"}}}, 26, 5),
	198	+	0,
	199	+	0,
	200	+	)
	201	+
	202	+	out.Reset()
	203	+	r.DrawLog([]string{"chat"}, []string{"input"}, 0, 0)
	204	+	if !strings.Contains(stripANSI(out.String()), "input") {
	205	+	t.Fatalf("right-bar fallback did not repaint flow content: %q", out.String())
	206	+	}
	207	+	if strings.Contains(out.String(), SeqClearScrollback) {
	208	+	t.Fatalf("right-bar fallback cleared terminal scrollback: %q", out.String())
	209	+	}
	210	+	}
	211	+
187	212		func TestRendererDrawRightBarUpdatesClearsAndResizes(t *testing.T) {
188	213		var out bytes.Buffer
189	214		r := NewRenderer(&out)


@@ -184,6 +184,31 @@ func TestJoinRightBarPreservesCellBudgetForUnicode(t *testing.T) {
184	}	184		}
185	}	185		}
186		186
		187	+	func TestRendererDrawRightBarToDrawLogKeepsScrollback(t *testing.T) {
		188	+	t.Setenv("TERM_PROGRAM", "")
		189	+
		190	+	var out bytes.Buffer
		191	+	r := NewRenderer(&out)
		192	+	r.SetTheme(Dark)
		193	+	r.Resize(80, 5)
		194	+	r.DrawRightBar(
		195	+	[]string{"chat"},
		196	+	[]string{"input"},
		197	+	RenderRightBar(Dark, []RightBarWidget{{Extension: "plan", Title: "Plan", Lines: []string{"task"}}}, 26, 5),
		198	+	0,
		199	+	0,
		200	+	)
		201	+
		202	+	out.Reset()
		203	+	r.DrawLog([]string{"chat"}, []string{"input"}, 0, 0)
		204	+	if !strings.Contains(stripANSI(out.String()), "input") {
		205	+	t.Fatalf("right-bar fallback did not repaint flow content: %q", out.String())
		206	+	}
		207	+	if strings.Contains(out.String(), SeqClearScrollback) {
		208	+	t.Fatalf("right-bar fallback cleared terminal scrollback: %q", out.String())
		209	+	}
		210	+	}
		211	+
187	func TestRendererDrawRightBarUpdatesClearsAndResizes(t *testing.T) {	212		func TestRendererDrawRightBarUpdatesClearsAndResizes(t *testing.T) {
188	var out bytes.Buffer	213		var out bytes.Buffer
189	r := NewRenderer(&out)	214		r := NewRenderer(&out)