fix(readline): make forward delete work properly

readline/cursor.go

@@ -100,12 +100,12 @@ func moveCursorBackwards(i int) {
 	printf("\x1b[%dD", i)
 }
 
-func (rl *Instance) backspace() {
+func (rl *Instance) backspace(forward bool) {
 	if len(rl.line) == 0 || rl.pos == 0 {
 		return
 	}
 
-	rl.deleteBackspace()
+	rl.deleteBackspace(forward)
 }
 
 func (rl *Instance) moveCursorByAdjust(adjust int) {

readline/line.go

@@ -125,14 +125,14 @@ func (rl *Instance) deleteX() {
 	rl.updateHelpers()
 }
 
-func (rl *Instance) deleteBackspace() {
+func (rl *Instance) deleteBackspace(forward bool) {
 	switch {
 	case len(rl.line) == 0:
 		return
-	case rl.pos == 0:
+	case forward:
-		rl.line = rl.line[1:]
+		rl.line = append(rl.line[:rl.pos], rl.line[rl.pos+1:]...)
 	case rl.pos > len(rl.line):
-		rl.backspace() // There is an infite loop going on here...
+		rl.backspace(forward) // There is an infite loop going on here...
 	case rl.pos == len(rl.line):
 		rl.pos--
 		rl.line = rl.line[:rl.pos]

readline/readline.go

@@ -214,7 +214,7 @@ func (rl *Instance) Readline() (string, error) {
 				// Vim mode has different behaviors
 				if rl.InputMode == Vim {
 					if rl.modeViMode == VimInsert {
-						rl.backspace()
+						rl.backspace(false)
 					} else if rl.pos != 0 {
 						rl.pos--
 					}
@@ -223,7 +223,7 @@ func (rl *Instance) Readline() (string, error) {
 				}
 
 				// Else emacs deletes a character
-				rl.backspace()
+				rl.backspace(false)
 				rl.renderHelpers()
 			}
 
@@ -704,7 +704,7 @@ func (rl *Instance) escapeSeq(r []rune) {
 		if rl.modeTabFind {
 			rl.backspaceTabFind()
 		} else {
-			rl.deleteBackspace()
+			rl.deleteBackspace(true)
 		}
 	case seqHome, seqHomeSc:
 		if rl.modeTabCompletion {