cmd: Fix panic if cmd ends on dash or underscore

cobra/cmd/add.go

@@ -77,6 +77,12 @@ func validateCmdName(source string) string {
 				output = source[:i]
 			}
 
+			// If it's last rune and it's dash or underscore,
+			// don't add it output and break the loop.
+			if i == l-1 {
+				break
+			}
+
 			// If next character is dash or underscore,
 			// just skip the current character.
 			if source[i+1] == '-' || source[i+1] == '_' {

cobra/cmd/add_test.go

@@ -87,6 +87,8 @@ func TestValidateCmdName(t *testing.T) {
 		{"cmd------Name", "cmdName"},
 		{"cmd______name", "cmdName"},
 		{"cmd------name", "cmdName"},
+		{"cmdName-----", "cmdName"},
+		{"cmdname-", "cmdname"},
 	}
 
 	for _, testCase := range testCases {