Fix ANSI processor to handle multi-line regions

src/ansi.go

@@ -36,11 +36,13 @@ func init() {
 	ansiRegex = regexp.MustCompile("\x1b\\[[0-9;]*[mK]")
 }
 
-func extractColor(str *string) (*string, []ansiOffset) {
+func extractColor(str *string, state *ansiState) (*string, []ansiOffset, *ansiState) {
 	var offsets []ansiOffset
-
 	var output bytes.Buffer
-	var state *ansiState
+
+	if state != nil {
+		offsets = append(offsets, ansiOffset{[2]int32{0, 0}, *state})
+	}
 
 	idx := 0
 	for _, offset := range ansiRegex.FindAllStringIndex(*str, -1) {
@@ -76,7 +78,7 @@ func extractColor(str *string) (*string, []ansiOffset) {
 		}
 	}
 	outputStr := output.String()
-	return &outputStr, offsets
+	return &outputStr, offsets, state
 }
 
 func interpretCode(ansiCode string, prevState *ansiState) *ansiState {

src/ansi_test.go

@@ -14,79 +14,89 @@ func TestExtractColor(t *testing.T) {
 	}
 
 	src := "hello world"
+	var state *ansiState
 	clean := "\x1b[0m"
-	check := func(assertion func(ansiOffsets []ansiOffset)) {
-		output, ansiOffsets := extractColor(&src)
+	check := func(assertion func(ansiOffsets []ansiOffset, state *ansiState)) {
+		output, ansiOffsets, newState := extractColor(&src, state)
+		state = newState
 		if *output != "hello world" {
 			t.Errorf("Invalid output: {}", output)
 		}
 		fmt.Println(src, ansiOffsets, clean)
-		assertion(ansiOffsets)
+		assertion(ansiOffsets, state)
 	}
 
-	check(func(offsets []ansiOffset) {
+	check(func(offsets []ansiOffset, state *ansiState) {
 		if len(offsets) > 0 {
 			t.Fail()
 		}
 	})
 
+	state = nil
 	src = "\x1b[0mhello world"
-	check(func(offsets []ansiOffset) {
+	check(func(offsets []ansiOffset, state *ansiState) {
 		if len(offsets) > 0 {
 			t.Fail()
 		}
 	})
 
+	state = nil
 	src = "\x1b[1mhello world"
-	check(func(offsets []ansiOffset) {
+	check(func(offsets []ansiOffset, state *ansiState) {
 		if len(offsets) != 1 {
 			t.Fail()
 		}
 		assert(offsets[0], 0, 11, -1, -1, true)
 	})
 
+	state = nil
 	src = "\x1b[1mhello \x1b[mworld"
-	check(func(offsets []ansiOffset) {
+	check(func(offsets []ansiOffset, state *ansiState) {
 		if len(offsets) != 1 {
 			t.Fail()
 		}
 		assert(offsets[0], 0, 6, -1, -1, true)
 	})
 
+	state = nil
 	src = "\x1b[1mhello \x1b[Kworld"
-	check(func(offsets []ansiOffset) {
+	check(func(offsets []ansiOffset, state *ansiState) {
 		if len(offsets) != 1 {
 			t.Fail()
 		}
 		assert(offsets[0], 0, 11, -1, -1, true)
 	})
 
+	state = nil
 	src = "hello \x1b[34;45;1mworld"
-	check(func(offsets []ansiOffset) {
+	check(func(offsets []ansiOffset, state *ansiState) {
 		if len(offsets) != 1 {
 			t.Fail()
 		}
 		assert(offsets[0], 6, 11, 4, 5, true)
 	})
 
+	state = nil
 	src = "hello \x1b[34;45;1mwor\x1b[34;45;1mld"
-	check(func(offsets []ansiOffset) {
+	check(func(offsets []ansiOffset, state *ansiState) {
 		if len(offsets) != 1 {
 			t.Fail()
 		}
 		assert(offsets[0], 6, 11, 4, 5, true)
 	})
 
+	state = nil
 	src = "hello \x1b[34;45;1mwor\x1b[0mld"
-	check(func(offsets []ansiOffset) {
+	check(func(offsets []ansiOffset, state *ansiState) {
 		if len(offsets) != 1 {
 			t.Fail()
 		}
 		assert(offsets[0], 6, 9, 4, 5, true)
 	})
 
+	state = nil
 	src = "hello \x1b[34;48;5;233;1mwo\x1b[38;5;161mr\x1b[0ml\x1b[38;5;161md"
-	check(func(offsets []ansiOffset) {
+	check(func(offsets []ansiOffset, state *ansiState) {
 		if len(offsets) != 3 {
 			t.Fail()
 		}
@@ -96,12 +106,47 @@ func TestExtractColor(t *testing.T) {
 	})
 
 	// {38,48};5;{38,48}
+	state = nil
 	src = "hello \x1b[38;5;38;48;5;48;1mwor\x1b[38;5;48;48;5;38ml\x1b[0md"
-	check(func(offsets []ansiOffset) {
+	check(func(offsets []ansiOffset, state *ansiState) {
 		if len(offsets) != 2 {
 			t.Fail()
 		}
 		assert(offsets[0], 6, 9, 38, 48, true)
 		assert(offsets[1], 9, 10, 48, 38, true)
 	})
+
+	src = "hello \x1b[32;1mworld"
+	check(func(offsets []ansiOffset, state *ansiState) {
+		if len(offsets) != 1 {
+			t.Fail()
+		}
+		if state.fg != 2 || state.bg != -1 || !state.bold {
+			t.Fail()
+		}
+		assert(offsets[0], 6, 11, 2, -1, true)
+	})
+
+	src = "hello world"
+	check(func(offsets []ansiOffset, state *ansiState) {
+		if len(offsets) != 1 {
+			t.Fail()
+		}
+		if state.fg != 2 || state.bg != -1 || !state.bold {
+			t.Fail()
+		}
+		assert(offsets[0], 0, 11, 2, -1, true)
+	})
+
+	src = "hello \x1b[0;38;5;200;48;5;100mworld"
+	check(func(offsets []ansiOffset, state *ansiState) {
+		if len(offsets) != 2 {
+			t.Fail()
+		}
+		if state.fg != 200 || state.bg != 100 || state.bold {
+			t.Fail()
+		}
+		assert(offsets[0], 0, 6, 2, -1, true)
+		assert(offsets[1], 6, 11, 200, 100, false)
+	})
 }

src/core.go

@@ -69,14 +69,17 @@ func Run(opts *Options) {
 	}
 	if opts.Ansi {
 		if opts.Theme != nil {
+			var state *ansiState
 			ansiProcessor = func(data *string) (*string, []ansiOffset) {
-				return extractColor(data)
+				trimmed, offsets, newState := extractColor(data, state)
+				state = newState
+				return trimmed, offsets
 			}
 		} else {
 			// When color is disabled but ansi option is given,
 			// we simply strip out ANSI codes from the input
 			ansiProcessor = func(data *string) (*string, []ansiOffset) {
-				trimmed, _ := extractColor(data)
+				trimmed, _, _ := extractColor(data, nil)
 				return trimmed, nil
 			}
 		}

src/terminal.go

@@ -378,6 +378,7 @@ func (t *Terminal) printHeader() {
 		return
 	}
 	max := C.MaxY()
+	var state *ansiState
 	for idx, lineStr := range t.header {
 		if !t.reverse {
 			idx = len(t.header) - idx - 1
@@ -389,7 +390,8 @@ func (t *Terminal) printHeader() {
 		if line >= max {
 			break
 		}
-		trimmed, colors := extractColor(&lineStr)
+		trimmed, colors, newState := extractColor(&lineStr, state)
+		state = newState
 		item := &Item{
 			text:   trimmed,
 			index:  0,