Replace auto type guard with struct

.eslintrc.js

@@ -29,10 +29,5 @@ module.exports = {
     },
   ],
 
-  ignorePatterns: [
-    '!.prettierrc.js',
-    '**/!.eslintrc.js',
-    '**/dist*/',
-    '**/*__GENERATED__*',
-  ],
+  ignorePatterns: ['!.prettierrc.js', '**/!.eslintrc.js', '**/dist*/'],
 };

.gitignore

@@ -1,5 +1,4 @@
 **/dist
-**/src/**/*__GENERATED__*
 
 # sed backup files
 *.*-e

packages/cli/.eslintrc.js

@@ -1,6 +1,5 @@
 module.exports = {
   extends: ['../../.eslintrc.js'],
-  ignorePatterns: ['**/*__GENERATED__*'],
   overrides: [
     {
       files: ['**/*.ts'],

packages/cli/package.json

@@ -16,16 +16,15 @@
   "scripts": {
     "shasum": "node ./scripts/computeSnapShasum.js",
     "build:init-template": "node ./scripts/createInitTemplate.js && yarn prettier --check src/cmds/init/init-template.json",
-    "build:guards": "ts-auto-guard --guard-file-name=__GENERATED__ ./src/utils/snap-config.ts",
     "build:tsc": "tsc --project ./tsconfig.local.json",
     "build:chmod": "chmod +x ./dist/main.js",
     "build:readme": "node ./scripts/updateReadme.js",
     "build": "yarn build:pre-tsc && yarn build:tsc && yarn build:post-tsc",
-    "build:pre-tsc": "yarn build:init-template && yarn build:guards",
+    "build:pre-tsc": "yarn build:init-template",
     "build:post-tsc": "yarn build:chmod && yarn build:readme",
     "build:clean": "yarn clean && yarn build",
     "build:watch": "tsc-watch --onSuccess 'yarn build:chmod'",
-    "clean": "rimraf '*.tsbuildinfo' 'dist/*' 'src/**/*__GENERATED__*'",
+    "clean": "rimraf '*.tsbuildinfo' 'dist/*'",
     "test": "yarn build:init-template && jest",
     "posttest": "jest-it-up",
     "test:watch": "yarn test --watch",
@@ -58,6 +57,7 @@
     "serve-handler": "^6.1.1",
     "ses": "^0.15.15",
     "slash": "^3.0.0",
+    "superstruct": "^0.16.7",
     "yargs": "^16.2.0",
     "yargs-parser": "^20.2.2"
   },
@@ -93,7 +93,6 @@
     "prettier": "^2.3.2",
     "prettier-plugin-packagejson": "^2.2.11",
     "rimraf": "^3.0.2",
-    "ts-auto-guard": "^2.3.0",
     "ts-jest": "^29.0.0",
     "ts-node": "^10.7.0",
     "tsc-watch": "^4.5.0",

packages/cli/src/tsconfig.json

@@ -1,5 +1,5 @@
 {
-  "extends": "../tsconfig.test.json",
+  "extends": "../tsconfig.json",
   "references": [
     {
       "path": "../utils"

packages/cli/src/utils/snap-config.ts

@@ -4,16 +4,37 @@ import type browserify from 'browserify';
 import { Arguments } from 'yargs';
 import yargsParse from 'yargs-parser';
 import yargs from 'yargs/yargs';
+import { object, optional, func, Infer, is } from 'superstruct';
 import builders from '../builders';
 import { CONFIG_FILE, logError } from './misc';
-import { isSnapConfig } from './snap-config.__GENERATED__';
 
-/** @see {isSnapConfig} ts-auto-guard:type-guard */
-export type SnapConfig = {
-  cliOptions?: Record<string, unknown>;
-  bundlerCustomizer?: (bundler: browserify.BrowserifyObject) => void;
+export type BundleCustomizer = (bundler: browserify.BrowserifyObject) => void;
+
+export const SnapConfigStruct = object({
+  cliOptions: optional(object()),
+  bundlerCustomizer: optional(func()),
+});
+
+export type SnapConfig = Omit<
+  Infer<typeof SnapConfigStruct>,
+  'bundlerCustomizer'
+> & {
+  bundlerCustomizer?: BundleCustomizer;
 };
 
+/**
+ * Check if the given value is a {@link SnapConfig} object. Note that this
+ * function does not check the validity of the `bundleCustomizer` property, as
+ * it is not possible to check the validity of a function in JavaScript.
+ *
+ * @param value - The value to check.
+ * @returns `true` if the value is a valid {@link SnapConfig} object, `false`
+ * otherwise.
+ */
+export function isSnapConfig(value: unknown): value is SnapConfig {
+  return is(value, SnapConfigStruct);
+}
+
 let snapConfigCache: SnapConfig | undefined;
 
 /**