diff --git a/src/ansi.go b/src/ansi.go index 3636e02..5856bd5 100644 --- a/src/ansi.go +++ b/src/ansi.go @@ -44,7 +44,21 @@ func init() { */ // The following regular expression will include not all but most of the // frequently used ANSI sequences - ansiRegex = regexp.MustCompile("\x1b[\\[()][0-9;]*[a-zA-Z@]|\x1b.|[\x0e\x0f]|.\x08") + ansiRegex = regexp.MustCompile("(?:\x1b[\\[()][0-9;]*[a-zA-Z@]|\x1b.|[\x0e\x0f]|.\x08)") +} + +func findAnsiStart(str string) int { + idx := 0 + for ; idx < len(str); idx++ { + b := str[idx] + if b == 0x1b || b == 0x0e || b == 0x0f { + return idx + } + if b == 0x08 && idx > 0 { + return idx - 1 + } + } + return idx } func extractColor(str string, state *ansiState, proc func(string, *ansiState) bool) (string, *[]ansiOffset, *ansiState) { @@ -55,41 +69,61 @@ func extractColor(str string, state *ansiState, proc func(string, *ansiState) bo offsets = append(offsets, ansiOffset{[2]int32{0, 0}, *state}) } - idx := 0 - for _, offset := range ansiRegex.FindAllStringIndex(str, -1) { - prev := str[idx:offset[0]] - output.WriteString(prev) + prevIdx := 0 + runeCount := 0 + for idx := 0; idx < len(str); { + idx += findAnsiStart(str[idx:]) + + // No sign of ANSI code + if idx == len(str) { + break + } + + // Make sure that we found an ANSI code + offset := ansiRegex.FindStringIndex(str[idx:]) + if offset == nil { + idx++ + continue + } + offset[0] += idx + offset[1] += idx + idx = offset[1] + + // Check if we should continue + prev := str[prevIdx:offset[0]] if proc != nil && !proc(prev, state) { return "", nil, nil } - newState := interpretCode(str[offset[0]:offset[1]], state) + prevIdx = offset[1] + runeCount += utf8.RuneCountInString(prev) + output.WriteString(prev) + + newState := interpretCode(str[offset[0]:offset[1]], state) if !newState.equals(state) { if state != nil { // Update last offset - (&offsets[len(offsets)-1]).offset[1] = int32(utf8.RuneCount(output.Bytes())) + (&offsets[len(offsets)-1]).offset[1] = int32(runeCount) } if newState.colored() { // Append new offset state = newState - newLen := int32(utf8.RuneCount(output.Bytes())) - offsets = append(offsets, ansiOffset{[2]int32{newLen, newLen}, *state}) + offsets = append(offsets, ansiOffset{[2]int32{int32(runeCount), int32(runeCount)}, *state}) } else { // Discard state state = nil } } - - idx = offset[1] } - rest := str[idx:] + rest := str[prevIdx:] if len(rest) > 0 { output.WriteString(rest) if state != nil { // Update last offset - (&offsets[len(offsets)-1]).offset[1] = int32(utf8.RuneCount(output.Bytes())) + runeCount += utf8.RuneCountInString(rest) + (&offsets[len(offsets)-1]).offset[1] = int32(runeCount) } } if proc != nil {