added WrapperError with the github reference

src/command/commands/composed/helper-object.ts

@@ -1,3 +1,4 @@
+import { WrapperError } from "../../../common/error";
 import { EmptyRecord } from "../../../common/types";
 import { Command } from "../..";
 import { showCommands } from "../helpers";
@@ -17,7 +18,7 @@ export const createHelperObject = <
   for (const name of commandNames) {
     const cmd = findByNameInComposed(commands, name);
     if (!cmd) {
-      throw new Error(
+      throw WrapperError.create(
         `Command ${name} not found in composed command ${
           showCommands(commands)
         }`,

src/command/commands/with-subcommands/subs.ts

@@ -5,6 +5,7 @@ import { CommandsTuple, YargsCommandBuilder } from "../../types";
 import { CommandBasic } from "../basic/type";
 
 import y from "yargs";
+import { WrapperError } from "../../../common/error";
 import { EmptyRecord } from "../../../common/types";
 import { command } from "../basic/command";
 import { GetCommandNameFromDesc } from "../basic/type-command-name";
@@ -113,7 +114,7 @@ export function subs(
   ) {
     // overload 2 or 3
     if (!(typeof subcommandsOrDescription === "string")) {
-      throw new Error("Invalid overload");
+      throw WrapperError.create("Invalid overload");
     }
 
     if (typeof builderOrSubcommands === "function") {
@@ -127,7 +128,7 @@ export function subs(
         return overload12(parentCommand, subcommands);
       }
       else {
-        throw new Error("Invalid overload");
+        throw WrapperError.create("Invalid overload");
       }
     }
     else {
@@ -139,13 +140,13 @@ export function subs(
         return overload12(parentCommand, builderOrSubcommands);
       }
       else {
-        throw new Error("Invalid overload");
+        throw WrapperError.create("Invalid overload");
       }
     }
   }
   else {
     if (typeof subcommandsOrDescription === "string") {
-      throw new Error("Invalid overload");
+      throw WrapperError.create("Invalid overload");
     }
     // overload 1 or 2
     return overload12(

src/common/error.ts

@@ -1,4 +1,17 @@
 export type ErrorType = {
-    error: string;
-    message: string;
-  };
+  error: string;
+  message: string;
+};
+
+export class WrapperError extends Error {
+  constructor(message: string) {
+    super(
+      `${message}. This shouldn't happen. Please open an issue at https://github.com/nktknshn/yargs-command-wrapper/issues`,
+    );
+    this.name = "WrapperError";
+  }
+
+  static create(message: string): WrapperError {
+    return new WrapperError(message);
+  }
+}

src/handler/create-handler-for/create-handler-for.ts

@@ -15,6 +15,7 @@ import { CommandArgs } from "../../command/commands/args/type-command-args";
 import { CommandArgsGeneric } from "../../command/commands/args/type-command-args-generic";
 import { NestedCommandArgs } from "../../command/commands/args/type-nested-command-args";
 import { showCommand } from "../../command/commands/helpers";
+import { WrapperError } from "../../common/error";
 import { EmptyRecord } from "../../common/types";
 import { ComposableHandlerFor } from "../handler-composable/composable-handler-for";
 import { showComposableHandler } from "../handler-composable/helpers";
@@ -81,7 +82,7 @@ export function createHandlerFor(
       return _createHandlerForCommand(command, functionOrRecord);
     }
     else {
-      throw new Error(
+      throw WrapperError.create(
         `Invalid handler for command ${command.commandName}. Expected function.`,
       );
     }
@@ -94,7 +95,7 @@ export function createHandlerFor(
       return _createHandlerForComposed(command, functionOrRecord);
     }
     else {
-      throw new Error(
+      throw WrapperError.create(
         `Invalid handler for composed command ${showCommand(command)}.`,
       );
     }
@@ -142,7 +143,7 @@ const _createHandlerForComposed = (
       if (!(commandName in functionOrRecord)) {
         console.error(args, functionOrRecord);
 
-        throw new Error(
+        throw WrapperError.create(
           `No handler found for command ${String(commandName)} in record`,
         );
       }
@@ -155,7 +156,9 @@ const _createHandlerForComposed = (
       );
 
       if (commandToHandle === undefined) {
-        throw new Error(`No command ${String(commandName)} among composed.`);
+        throw WrapperError.create(
+          `No command ${String(commandName)} among composed.`,
+        );
       }
 
       return composedHandlerFunction(args, commandToHandle, handler);
@@ -208,15 +211,17 @@ const _createHandlerForSubcommands = (
 
       if (command.command.commandName !== commandName) {
         console.error(args, command);
-        throw new Error(`Unmatched command name ${commandName}`);
+        throw WrapperError.create(`Unmatched command name ${commandName}`);
       }
 
       const _args = popCommand(args);
 
       if (!(_args.command in functionOrRecord)) {
         console.error(_args, functionOrRecord);
 
-        throw new Error(`No handler found for command ${commandName}`);
+        throw WrapperError.create(
+          `No handler found for command ${commandName}`,
+        );
       }
 
       const handler = functionOrRecord[_args.command];
@@ -228,7 +233,9 @@ const _createHandlerForSubcommands = (
       );
 
       if (commandToHandle === undefined) {
-        throw new Error(`No command ${commandName} among subcommands`);
+        throw WrapperError.create(
+          `No command ${commandName} among subcommands`,
+        );
       }
 
       return composedHandlerFunction(_args, commandToHandle, handler);
@@ -268,7 +275,7 @@ const composedHandlerFunction = (
       }
       else {
         // somehow the handler does not support the command (shouldn't happen if the typing works properly)
-        throw new Error(
+        throw WrapperError.create(
           `Invalid handler for ${commandToHandle.commandName}: ${
             showComposableHandler(handler)
           }`,
@@ -277,7 +284,7 @@ const composedHandlerFunction = (
     }
     else {
       // handler for a basic command is a record (shouldn't happen if the typing works properly)
-      throw new Error(
+      throw WrapperError.create(
         `Invalid handler for command ${commandName}. Expected function or composable handler.`,
       );
     }

src/handler/handler-composable/compose.ts

@@ -1,4 +1,5 @@
 import { CommandArgs } from "../../command/commands/args/type-command-args";
+import { WrapperError } from "../../common/error";
 import { ComposableHandler } from "./type-composable-handler";
 import { ComposeArgv, ComposedHandlers } from "./types-compose";
 
@@ -46,7 +47,9 @@ export function composeHandlers(
       }
     }
 
-    throw new Error(`No handler found for command ${String(args.command)}`);
+    throw WrapperError.create(
+      `No handler found for command ${String(args.command)}`,
+    );
   };
 
   return {