feat: added alt backspace keybinding (#132)

Co-authored-by: Renzix <DanielDeBruno@renzix.com>

readline/codes.go

@@ -39,18 +39,20 @@ const (
 
 // Escape sequences
 var (
-	seqUp        = string([]byte{27, 91, 65})
+	seqUp           = string([]byte{27, 91, 65})
-	seqDown      = string([]byte{27, 91, 66})
+	seqDown         = string([]byte{27, 91, 66})
-	seqForwards  = string([]byte{27, 91, 67})
+	seqForwards     = string([]byte{27, 91, 67})
-	seqBackwards = string([]byte{27, 91, 68})
+	seqBackwards    = string([]byte{27, 91, 68})
-	seqHome      = string([]byte{27, 91, 72})
+	seqHome         = string([]byte{27, 91, 72})
-	seqHomeSc    = string([]byte{27, 91, 49, 126})
+	seqHomeSc       = string([]byte{27, 91, 49, 126})
-	seqEnd       = string([]byte{27, 91, 70})
+	seqEnd          = string([]byte{27, 91, 70})
-	seqEndSc     = string([]byte{27, 91, 52, 126})
+	seqEndSc        = string([]byte{27, 91, 52, 126})
-	seqDelete    = string([]byte{27, 91, 51, 126})
+	seqDelete       = string([]byte{27, 91, 51, 126})
-	seqShiftTab  = string([]byte{27, 91, 90})
+	seqDelete2      = string([]byte{27, 91, 80})
-	seqAltQuote  = string([]byte{27, 34})  // Added for showing registers ^["
+	seqShiftTab     = string([]byte{27, 91, 90})
-	seqAltR      = string([]byte{27, 114}) // Used for alternative history
+	seqAltQuote     = string([]byte{27, 34})  // Added for showing registers ^["
+	seqAltR         = string([]byte{27, 114}) // Used for alternative history
+	seqAltBackspace = string([]byte{27, 127})
 )
 
 const (

readline/readline.go

@@ -712,12 +712,15 @@ func (rl *Instance) escapeSeq(r []rune) {
 		rl.updateHelpers()
 		return
 
-	case seqDelete:
+	case seqDelete,seqDelete2:
 		if rl.modeTabFind {
 			rl.backspaceTabFind()
 		} else {
-			rl.deleteBackspace(true)
+			if (rl.pos < len(rl.line)) {
+				rl.deleteBackspace(true)
+			}
 		}
+
 	case seqHome, seqHomeSc:
 		if rl.modeTabCompletion {
 			return
@@ -752,6 +755,19 @@ func (rl *Instance) escapeSeq(r []rune) {
 		rl.updateTabFind([]rune{})
 		rl.viUndoSkipAppend = true
 
+	case seqAltBackspace:
+		if rl.modeTabCompletion {
+			rl.resetVirtualComp(false)
+		}
+		// This is only available in Insert mode
+		if rl.modeViMode != VimInsert {
+			return
+		}
+
+		rl.saveToRegister(rl.viJumpB(tokeniseLine))
+		rl.viDeleteByAdjust(rl.viJumpB(tokeniseLine))
+		rl.updateHelpers()
+
 	default:
 		if rl.modeTabFind {
 			return