feat: modify return codes

Modify exit codes. `cheat` now returns an exit code value `2` on errors
pertaining to a cheatsheet not being found.

BREAKING CHANGE

cmd/cheat/cmd_list.go

@@ -81,9 +81,9 @@ func cmdList(opts map[string]interface{}, conf config.Config) {
 		flattened = filtered
 	}
 
-	// exit early if no cheatsheets are available
+	// return exit code 2 if no cheatsheets are available
 	if len(flattened) == 0 {
-		os.Exit(0)
+		os.Exit(2)
 	}
 
 	// initialize a tabwriter to produce cleanly columnized output

cmd/cheat/cmd_remove.go

@@ -37,8 +37,8 @@ func cmdRemove(opts map[string]interface{}, conf config.Config) {
 	// fail early if the requested cheatsheet does not exist
 	sheet, ok := consolidated[cheatsheet]
 	if !ok {
-		fmt.Fprintln(os.Stderr, fmt.Sprintf("no cheatsheet found for '%s'.\n", cheatsheet))
-		os.Exit(1)
+		fmt.Fprintln(os.Stderr, fmt.Sprintf("No cheatsheet found for '%s'.\n", cheatsheet))
+		os.Exit(2)
 	}
 
 	// fail early if the sheet is read-only

cmd/cheat/cmd_search.go

@@ -46,7 +46,7 @@ func cmdSearch(opts map[string]interface{}, conf config.Config) {
 		s, ok := consolidated[cheatsheet]
 		if !ok {
 			fmt.Printf("No cheatsheet found for '%s'.\n", cheatsheet)
-			os.Exit(0)
+			os.Exit(2)
 		}
 
 		consolidated = map[string]sheet.Sheet{

cmd/cheat/cmd_view.go

@@ -39,7 +39,7 @@ func cmdView(opts map[string]interface{}, conf config.Config) {
 	sheet, ok := consolidated[cheatsheet]
 	if !ok {
 		fmt.Printf("No cheatsheet found for '%s'.\n", cheatsheet)
-		os.Exit(0)
+		os.Exit(2)
 	}
 
 	// apply colorization if requested