Parse ESC screen attribute controls

Author: SqlRush

docs/cc-100-roadmap.md

@@ -338,6 +338,8 @@ M7 补充：terminal ESC parser 现在把 charset selection (`ESC ( B` / `ESC )
 
 M7 补充：terminal ESC parser 现在也把 ISO-2022 charset shift 控制 (`ESC N`、`ESC n`、`ESC o`、`ESC |`、`ESC }`、`ESC ~`) 解析成结构化 charset-shift action，并在可见文本管线中消费，继续减少真实终端输出里的 unknown 控制序列。
 
+M7 补充：terminal ESC parser 现在把 DEC line/screen attribute 序列 (`ESC # 3/4/5/6/8`) 解析成结构化 screen action，并在 terminal parser 中透传 alignment-test/line-size 控制，避免 ANSI snapshot 管线落入 unknown。
+
 M7 补充：terminal CSI parser 现在把 DEC selective erase `CSI ? Ps J` / `CSI ? Ps K` 标记为 selective display/line erase，和普通 ED/EL 区分开。
 
 M7 补充：terminal CSI parser 现在把 ECMA `CSI Ps N` / `CSI Ps O` 解析成 erase-in-field / erase-in-area action，覆盖 to-end/to-start/all 三种 region。
@@ -894,6 +896,8 @@ M7 补充：prompt history `LogEntry` 读取现在接受 `sessionID`/`session`/`
 
 本轮补充：terminal CSI parser 把 DECSTR soft reset (`CSI !p`) 归入 reset action，并在 terminal parser 中清理 SGR/link 状态。
 
+本轮补充：terminal ESC parser 把 DEC line/screen attribute (`ESC # 3/4/5/6/8`) 归入 screen action，terminal parser 会结构化透传 double-height top/bottom、single/double-width 和 alignment-test 控制，继续减少真实 ANSI 输出里的 unknown fallback。
+
 本轮补充：renderer/snapshot 增加 opt-in DEC 2026 synchronized output 包裹入口，可用官方 BSU/ESU (`CSI ?2026h`/`CSI ?2026l`) 生成整帧 ANSI fixture，同时默认渲染保持不变。
 
 本轮补充：terminal OSC helper 增加 OSC 0 title/icon 序列生成，输入会先 strip ANSI；`StripANSI` 现在会完整跳过 OSC/DCS/APC/PM/SOS payload，避免 title/snapshot 可见文本被终端控制串污染。

docs/claude-code-go-rewrite-plan.md

@@ -463,6 +463,7 @@ test/parity/                 # golden tests against TS/official behavior
 - 本轮补充：terminal CSI parser 现在识别带 intermediate space 的 `CSI Ps SP @` / `CSI Ps SP A` scroll-left/right 序列，避免误解析成 insert-characters 或 cursor-up。
 - 本轮补充：terminal ESC parser 现在把 charset selection (`ESC ( B` / `ESC ) 0` / `ESC * B` / `ESC / A` / `ESC % G` 等) 解析成结构化 charset action，并在 terminal parser 可见文本管线中消费，避免常见终端 charset 选择序列残留为 unknown。
 - 本轮补充：terminal ESC parser 现在也把 ISO-2022 charset shift 控制 (`ESC N`、`ESC n`、`ESC o`、`ESC |`、`ESC }`、`ESC ~`) 解析成结构化 charset-shift action，并在可见文本管线中消费，继续减少真实终端输出里的 unknown 控制序列。
+- 本轮补充：terminal ESC parser 现在把 DEC line/screen attribute (`ESC # 3/4/5/6/8`) 解析成结构化 screen action，terminal parser 会透传 double-height top/bottom、single/double-width 和 alignment-test 控制。
 - 本轮补充：terminal CSI parser 现在把 DEC selective erase `CSI ? Ps J` / `CSI ? Ps K` 标记为 selective display/line erase，和普通 ED/EL 区分开。
 - 本轮补充：terminal CSI parser 现在把 ECMA `CSI Ps N` / `CSI Ps O` 解析成 erase-in-field / erase-in-area action，覆盖 to-end/to-start/all 三种 region。
 - 本轮补充：terminal CSI parser 把 DEC insert/delete columns (`CSI Ps ' }` / `CSI Ps ' ~`) 归入 edit action，避免列编辑控制序列落入 unknown fallback。

docs/first-second-parity-audit.md

@@ -378,6 +378,7 @@ M7 progress now includes:
 - `internal/tui`: terminal CSI parser now recognizes DEC left/right margin mode (`?69h/l`) as a structured `leftRightMarginMode` action.
 - `internal/tui`: terminal CSI parsing now distinguishes parameterized `CSI Pl;Pr s` left/right horizontal margin regions from bare `CSI s` save-cursor semantics.
 - `internal/tui`: terminal CSI parsing now recognizes intermediate-space `CSI Ps SP @` / `CSI Ps SP A` scroll-left/right sequences instead of misclassifying them as insert-characters or cursor-up.
+- `internal/tui`: terminal ESC parsing now exposes DEC line/screen attribute controls (`ESC # 3/4/5/6/8`) as structured screen actions instead of falling back to unknown.
 - `internal/tui`: terminal CSI parsing now marks DEC selective erase `CSI ? Ps J` / `CSI ? Ps K` separately from ordinary ED/EL erase actions.
 - `internal/tui`: terminal CSI parsing now exposes ECMA `CSI Ps N` / `CSI Ps O` erase-in-field and erase-in-area actions with the same to-end/to-start/all regions used by other erase operations.
 - `internal/tui`: terminal CSI parsing now treats explicit zero count/position params as ANSI defaults for cursor movement/position/column, insert/repeat/erase chars, and scroll actions while preserving raw zero selector semantics for mode/report/erase selector sequences.

internal/tui/terminal_esc.go

@@ -11,6 +11,7 @@ const (
 	ESCReverseIndex              = "\x1bM"
 	ESCNextLine                  = "\x1bE"
 	ESCTabSet                    = "\x1bH"
+	ESCScreenAttributes          = '#'
 	ESCFinalStart                = 0x30
 	ESCFinalEnd                  = 0x7e
 	ESCCharsetSingleShift2       = 'N'
@@ -38,13 +39,29 @@ const (
 	ESCActionReset        ESCActionType = "reset"
 	ESCActionCharset      ESCActionType = "charset"
 	ESCActionCharsetShift ESCActionType = "charsetShift"
+	ESCActionScreen       ESCActionType = "screen"
 	ESCActionUnknown      ESCActionType = "unknown"
 )
 
+type ESCScreenActionType string
+
+const (
+	ESCScreenActionDoubleHeightTop    ESCScreenActionType = "doubleHeightTop"
+	ESCScreenActionDoubleHeightBottom ESCScreenActionType = "doubleHeightBottom"
+	ESCScreenActionSingleWidth        ESCScreenActionType = "singleWidth"
+	ESCScreenActionDoubleWidth        ESCScreenActionType = "doubleWidth"
+	ESCScreenActionAlignmentTest      ESCScreenActionType = "alignmentTest"
+)
+
+type ESCScreenAction struct {
+	Type ESCScreenActionType
+}
+
 type ESCAction struct {
 	Type              ESCActionType
 	Cursor            CSICursorAction
 	Mode              CSIModeAction
+	Screen            ESCScreenAction
 	CharsetSlot       byte
 	CharsetDesignator byte
 	CharsetShift      string
@@ -72,6 +89,11 @@ func ParseESCContent(chars string) (ESCAction, bool) {
 	if shift, ok := escCharsetShift(chars[0]); ok && len(chars) == 1 {
 		return ESCAction{Type: ESCActionCharsetShift, CharsetShift: shift, Sequence: ESCPrefix + chars}, true
 	}
+	if chars[0] == ESCScreenAttributes && len(chars) == 2 {
+		if screenType, ok := escScreenActionType(chars[1]); ok {
+			return ESCAction{Type: ESCActionScreen, Screen: ESCScreenAction{Type: screenType}, Sequence: ESCPrefix + chars}, true
+		}
+	}
 	switch chars[0] {
 	case 'c':
 		return ESCAction{Type: ESCActionReset}, true
@@ -105,6 +127,23 @@ func isESCCharsetSelector(b byte) bool {
 	}
 }
 
+func escScreenActionType(b byte) (ESCScreenActionType, bool) {
+	switch b {
+	case '3':
+		return ESCScreenActionDoubleHeightTop, true
+	case '4':
+		return ESCScreenActionDoubleHeightBottom, true
+	case '5':
+		return ESCScreenActionSingleWidth, true
+	case '6':
+		return ESCScreenActionDoubleWidth, true
+	case '8':
+		return ESCScreenActionAlignmentTest, true
+	default:
+		return "", false
+	}
+}
+
 func escCharsetShift(b byte) (string, bool) {
 	switch b {
 	case ESCCharsetSingleShift2:

internal/tui/terminal_parser.go

@@ -29,6 +29,7 @@ const (
 	TerminalActionShell         TerminalActionType = "shellIntegration"
 	TerminalActionBell          TerminalActionType = "bell"
 	TerminalActionReset         TerminalActionType = "reset"
+	TerminalActionScreen        TerminalActionType = "screen"
 	TerminalActionStringControl TerminalActionType = "stringControl"
 	TerminalActionUnknown       TerminalActionType = "unknown"
 )
@@ -49,6 +50,7 @@ type TerminalAction struct {
 	Scroll    CSIScrollAction
 	Mode      CSIModeAction
 	Modes     []CSIModeAction
+	Screen    ESCScreenAction
 	OSC       OSCAction
 	String    TerminalStringControlAction
 	Sequence  string
@@ -363,6 +365,8 @@ func (p *TerminalParser) processSequence(sequence string) (TerminalAction, bool)
 		case ESCActionReset:
 			p.Reset()
 			return TerminalAction{Type: TerminalActionReset}, true
+		case ESCActionScreen:
+			return TerminalAction{Type: TerminalActionScreen, Screen: action.ESC.Screen}, true
 		case ESCActionCharset, ESCActionCharsetShift:
 			return TerminalAction{}, false
 		default:

internal/tui/terminal_sequence_test.go

@@ -99,6 +99,10 @@ func TestParseTerminalSequenceDispatchesActions(t *testing.T) {
 	if !ok || keypadNumeric.Type != TerminalSequenceESC || keypadNumeric.ESC.Type != ESCActionMode || keypadNumeric.ESC.Mode.Type != CSIModeActionApplicationKeypad || keypadNumeric.ESC.Mode.Enabled {
 		t.Fatalf("numeric keypad esc dispatch = %#v ok=%v", keypadNumeric, ok)
 	}
+	screen, ok := ParseTerminalSequence("\x1b#8")
+	if !ok || screen.Type != TerminalSequenceESC || screen.ESC.Type != ESCActionScreen || screen.ESC.Screen.Type != ESCScreenActionAlignmentTest {
+		t.Fatalf("screen esc dispatch = %#v ok=%v", screen, ok)
+	}
 	if text, ok := ParseTerminalSequence("plain"); ok || text.Type != "" {
 		t.Fatalf("plain dispatch = %#v ok=%v", text, ok)
 	}

internal/tui/tui_test.go

@@ -5807,6 +5807,23 @@ func TestParseESCSequenceActions(t *testing.T) {
 		}
 	}
 
+	screenCases := []struct {
+		seq  string
+		want ESCScreenActionType
+	}{
+		{seq: "\x1b#3", want: ESCScreenActionDoubleHeightTop},
+		{seq: "\x1b#4", want: ESCScreenActionDoubleHeightBottom},
+		{seq: "\x1b#5", want: ESCScreenActionSingleWidth},
+		{seq: "\x1b#6", want: ESCScreenActionDoubleWidth},
+		{seq: "\x1b#8", want: ESCScreenActionAlignmentTest},
+	}
+	for _, tc := range screenCases {
+		screen, ok := ParseESCSequence(tc.seq)
+		if !ok || screen.Type != ESCActionScreen || screen.Screen.Type != tc.want {
+			t.Fatalf("screen action for %q = %#v ok=%v", tc.seq, screen, ok)
+		}
+	}
+
 	reset, ok := ParseESCSequence(ESCResetSequence)
 	if !ok || reset.Type != ESCActionReset {
 		t.Fatalf("reset action = %#v", reset)
@@ -5850,6 +5867,11 @@ func TestParseESCSequenceActions(t *testing.T) {
 		t.Fatalf("terminal parser keypad esc actions = %#v", actions)
 	}
 
+	actions = parser.Feed("\x1b#8")
+	if len(actions) != 1 || actions[0].Type != TerminalActionScreen || actions[0].Screen.Type != ESCScreenActionAlignmentTest {
+		t.Fatalf("terminal parser screen actions = %#v", actions)
+	}
+
 	unknown, ok := ParseESCContent("]not-osc")
 	if !ok || unknown.Type != ESCActionUnknown || unknown.Sequence != "\x1b]not-osc" {
 		t.Fatalf("unknown esc action = %#v", unknown)