fix(readline): use invert for completion highlight instead of hardcoded colors

if an alias is something which isn't valid syntax,
specifically if hilbish cant split up the input
properly to execute, it will report the error to
the user. the previous behaviour was a panic since
on error the args slice will be of length 0

this is basically an edge case and fixes a bug
which shouldnt happen normally

api.go

@@ -325,6 +325,7 @@ func hlprompt(t *rt.Thread, c *rt.GoCont) (rt.Cont, error) {
 		return nil, err
 	}
 	typ := "left"
+	// optional 2nd arg
 	if len(c.Etc()) != 0 {
 		ltyp := c.Etc()[0]
 		var ok bool

exec.go

@@ -42,13 +42,13 @@ func runInput(input string, priv bool) {
 					cmdFinish(0, input, priv)
 					return
 				}
-				input, exitCode, err = handleSh(cmdString)
+				input, exitCode, err = handleSh(input)
 				if err != nil {
 					fmt.Fprintln(os.Stderr, err)
 				}
 				cmdFinish(exitCode, input, priv)
 			case "hybridRev":
-				_, _, err = handleSh(cmdString)
+				_, _, err = handleSh(input)
 				if err == nil {
 					cmdFinish(0, input, priv)
 					return
@@ -65,7 +65,7 @@ func runInput(input string, priv bool) {
 				}
 				cmdFinish(exitCode, input, priv)
 			case "sh":
-				input, exitCode, err = handleSh(cmdString)
+				input, exitCode, err = handleSh(input)
 				if err != nil {
 					fmt.Fprintln(os.Stderr, err)
 				}
@@ -220,7 +220,11 @@ func execHandle(bg bool) interp.ExecHandlerFunc {
 
 			// If alias was found, use command alias
 			argstring = aliases.Resolve(argstring)
-			args, _ = shell.Fields(argstring, nil)
+			var err error
+			args, err = shell.Fields(argstring, nil)
+			if err != nil {
+				return err
+			}
 		}
 
 		// If command is defined in Lua then run it

readline/codes.go

@@ -85,6 +85,7 @@ const (
 	seqBold       = "\x1b[1m"
 	seqUnderscore = "\x1b[4m"
 	seqBlink      = "\x1b[5m"
+	seqInvert     = "\x1b[7m"
 )
 
 // Text colours

readline/comp-grid.go

@@ -121,7 +121,7 @@ func (g *CompletionGroup) writeGrid(rl *Instance) (comp string) {
 		}
 
 		if (x == g.tcPosX && y == g.tcPosY) && (g.isCurrent) {
-			comp += seqCtermFg255 + seqFgBlackBright
+			comp += seqInvert
 		}
 
 		comp += fmt.Sprintf("%-"+cellWidth+"s %s", g.Suggestions[i], seqReset)

readline/comp-list.go

@@ -188,7 +188,7 @@ func (g *CompletionGroup) writeList(rl *Instance) (comp string) {
 	// function highlights the cell depending on current selector place.
 	highlight := func(y int, x int) string {
 		if y == g.tcPosY && x == g.tcPosX && g.isCurrent {
-			return seqCtermFg255 + seqFgBlackBright
+			return seqInvert
 		}
 		return ""
 	}

readline/comp-map.go

@@ -101,7 +101,7 @@ func (g *CompletionGroup) writeMap(rl *Instance) (comp string) {
 	// Highlighting function
 	highlight := func(y int) string {
 		if y == g.tcPosY && g.isCurrent {
-			return seqCtermFg255 + seqFgBlackBright
+			return seqInvert
 		}
 		return ""
 	}