refactor(ansi): drop grapheme states

We don't need to keep track of grapheme states, see rivo/uniseg#58

ansi/parser.go

@@ -238,9 +238,7 @@ func (p *Parser) performAction(dispatcher ParserDispatcher, action parser.Action
 			// Collect intermediate bytes
 			// we only store the last intermediate byte
 			p.Cmd &^= 0xff << parser.IntermedShift
-			// p.Cmd[2] &^= 0xff
 			p.Cmd |= int(b) << parser.IntermedShift
-			// p.Cmd[2] |= b
 		}
 
 	case parser.ParamAction:

ansi/truncate.go

@@ -26,7 +26,6 @@ func Truncate(s string, length int, tail string) string {
 	var buf bytes.Buffer
 	curWidth := 0
 	ignoring := false
-	gstate := -1
 	pstate := parser.GroundState // initial state
 	b := []byte(s)
 	i := 0
@@ -41,7 +40,7 @@ func Truncate(s string, length int, tail string) string {
 		if state == parser.Utf8State {
 			// This action happens when we transition to the Utf8State.
 			var width int
-			cluster, _, width, gstate = uniseg.FirstGraphemeCluster(b[i:], gstate)
+			cluster, _, width, _ = uniseg.FirstGraphemeCluster(b[i:], -1)
 
 			// increment the index by the length of the cluster
 			i += len(cluster)
@@ -65,7 +64,6 @@ func Truncate(s string, length int, tail string) string {
 			curWidth += width
 			buf.Write(cluster)
 
-			gstate = -1 // reset grapheme state otherwise, width calculation might be off
 			// Done collecting, now we're back in the ground state.
 			pstate = parser.GroundState
 			continue

ansi/width.go

@@ -68,7 +68,6 @@ func StringWidth(s string) int {
 	}
 
 	var (
-		gstate  = -1
 		pstate  = parser.GroundState // initial state
 		cluster string
 		width   int
@@ -78,7 +77,7 @@ func StringWidth(s string) int {
 		state, action := parser.Table.Transition(pstate, s[i])
 		if state == parser.Utf8State {
 			var w int
-			cluster, _, w, gstate = uniseg.FirstGraphemeClusterInString(s[i:], gstate)
+			cluster, _, w, _ = uniseg.FirstGraphemeClusterInString(s[i:], -1)
 			width += w
 			i += len(cluster) - 1
 			pstate = parser.GroundState
@@ -89,9 +88,6 @@ func StringWidth(s string) int {
 			width++
 		}
 
-		// Reset uniseg state when we're not in a printable state.
-		gstate = -1
-
 		pstate = state
 	}
 

ansi/wrap.go

@@ -27,7 +27,6 @@ func Hardwrap(s string, limit int, preserveSpace bool) string {
 		buf          bytes.Buffer
 		curWidth     int
 		forceNewline bool
-		gstate       = -1
 		pstate       = parser.GroundState // initial state
 		b            = []byte(s)
 	)
@@ -42,7 +41,7 @@ func Hardwrap(s string, limit int, preserveSpace bool) string {
 		state, action := parser.Table.Transition(pstate, b[i])
 		if state == parser.Utf8State {
 			var width int
-			cluster, _, width, gstate = uniseg.FirstGraphemeCluster(b[i:], gstate)
+			cluster, _, width, _ = uniseg.FirstGraphemeCluster(b[i:], -1)
 			i += len(cluster)
 
 			if curWidth+width > limit {
@@ -58,7 +57,6 @@ func Hardwrap(s string, limit int, preserveSpace bool) string {
 
 			buf.Write(cluster)
 			curWidth += width
-			gstate = -1 // reset grapheme state otherwise, width calculation might be off
 			pstate = parser.GroundState
 			continue
 		}
@@ -120,7 +118,6 @@ func Wordwrap(s string, limit int, breakpoints string) string {
 		space    bytes.Buffer
 		curWidth int
 		wordLen  int
-		gstate   = -1
 		pstate   = parser.GroundState // initial state
 		b        = []byte(s)
 	)
@@ -154,7 +151,7 @@ func Wordwrap(s string, limit int, breakpoints string) string {
 		state, action := parser.Table.Transition(pstate, b[i])
 		if state == parser.Utf8State {
 			var width int
-			cluster, _, width, gstate = uniseg.FirstGraphemeCluster(b[i:], gstate)
+			cluster, _, width, _ = uniseg.FirstGraphemeCluster(b[i:], -1)
 			i += len(cluster)
 
 			r, _ := utf8.DecodeRune(cluster)
@@ -247,9 +244,8 @@ func Wrap(s string, limit int, breakpoints string) string {
 		buf      bytes.Buffer
 		word     bytes.Buffer
 		space    bytes.Buffer
-		curWidth int // written width of the line
-		wordLen  int // word buffer len without ANSI escape codes
-		gstate   = -1
+		curWidth int                  // written width of the line
+		wordLen  int                  // word buffer len without ANSI escape codes
 		pstate   = parser.GroundState // initial state
 		b        = []byte(s)
 	)
@@ -283,7 +279,7 @@ func Wrap(s string, limit int, breakpoints string) string {
 		state, action := parser.Table.Transition(pstate, b[i])
 		if state == parser.Utf8State {
 			var width int
-			cluster, _, width, gstate = uniseg.FirstGraphemeCluster(b[i:], gstate)
+			cluster, _, width, _ = uniseg.FirstGraphemeCluster(b[i:], -1)
 			i += len(cluster)
 
 			r, _ := utf8.DecodeRune(cluster)