Support full-line background color in the list section

Close #4432

src/ansi.go

@@ -156,13 +156,13 @@ func isCtrlSeqStart(c uint8) bool {
 // nextAnsiEscapeSequence returns the ANSI escape sequence and is equivalent to
 // calling FindStringIndex() on the below regex (which was originally used):
 //
-// "(?:\x1b[\\[()][0-9;:?]*[a-zA-Z@]|\x1b][0-9]+[;:][[:print:]]+(?:\x1b\\\\|\x07)|\x1b.|[\x0e\x0f]|.\x08)"
+// "(?:\x1b[\\[()][0-9;:?]*[a-zA-Z@]|\x1b][0-9]+[;:][[:print:]]+(?:\x1b\\\\|\x07)|\x1b.|[\x0e\x0f]|.\x08|\n)"
 func nextAnsiEscapeSequence(s string) (int, int) {
 	// fast check for ANSI escape sequences
 	i := 0
 	for ; i < len(s); i++ {
 		switch s[i] {
-		case '\x0e', '\x0f', '\x1b', '\x08':
+		case '\x0e', '\x0f', '\x1b', '\x08', '\n':
 			// We ignore the fact that '\x08' cannot be the first char
 			// in the string and be an escape sequence for the sake of
 			// speed and simplicity.
@@ -174,6 +174,9 @@ func nextAnsiEscapeSequence(s string) (int, int) {
 Loop:
 	for ; i < len(s); i++ {
 		switch s[i] {
+		case '\n':
+			// match: `\n`
+			return i, i + 1
 		case '\x08':
 			// backtrack to match: `.\x08`
 			if i > 0 && s[i-1] != '\n' {
@@ -265,13 +268,27 @@ func extractColor(str string, state *ansiState, proc func(string, *ansiState) bo
 			output.WriteString(prev)
 		}
 
-		newState := interpretCode(str[start:idx], state)
-		if !newState.equals(state) {
+		code := str[start:idx]
+		newState := interpretCode(code, state)
+		if code == "\n" || !newState.equals(state) {
 			if state != nil {
 				// Update last offset
 				(&offsets[len(offsets)-1]).offset[1] = int32(runeCount)
 			}
 
+			if code == "\n" {
+				output.WriteRune('\n')
+				// Full-background marker
+				if newState.lbg >= 0 {
+					marker := newState
+					marker.attr |= tui.FullBg
+					offsets = append(offsets, ansiOffset{
+						[2]int32{int32(runeCount), int32(runeCount)},
+						marker,
+					})
+				}
+			}
+
 			if newState.colored() {
 				// Append new offset
 				if pstate == nil {
@@ -349,6 +366,13 @@ func parseAnsiCode(s string) (int, string) {
 }
 
 func interpretCode(ansiCode string, prevState *ansiState) ansiState {
+	if ansiCode == "\n" {
+		if prevState != nil {
+			return *prevState
+		}
+		return ansiState{-1, -1, 0, -1, nil}
+	}
+
 	var state ansiState
 	if prevState == nil {
 		state = ansiState{-1, -1, 0, -1, nil}
@@ -435,6 +459,7 @@ func interpretCode(ansiCode string, prevState *ansiState) ansiState {
 					state.fg = -1
 					state.bg = -1
 					state.attr = 0
+					state.lbg = -1
 					state256 = 0
 				default:
 					if num >= 30 && num <= 37 {
@@ -477,6 +502,7 @@ func interpretCode(ansiCode string, prevState *ansiState) ansiState {
 		state.fg = -1
 		state.bg = -1
 		state.attr = 0
+		state.lbg = -1
 	}
 
 	if state256 > 0 {