Check types for mocks

Author: alihcsumer

packages/pluggable-widgets-tools/package.json

@@ -12,7 +12,8 @@
   },
   "scripts": {
     "prepack": "shx rm -rf dist && tsc",
-    "test": "jest"
+    "typecheck:test-config": "tsc -p test-config/tsconfig.json",
+    "test": "tsc -p test-config/tsconfig.json && jest"
   },
   "files": [
     "bin",

packages/pluggable-widgets-tools/test-config/__mocks__/mendix.js

@@ -1,15 +1,26 @@
-// Runtime mock for the types-only `mendix` package, whose real entry throws
-// ("This package should not be used in the runtime"). `@swc/jest` can't inline
-// the ambient `const enum ValueStatus`, so it emits a live `require("mendix")`
-// that needs this safe module exporting the enum values widget code uses.
-//
-// Keep values in sync with node_modules/mendix/index.d.ts.
+// @ts-check
+// Runtime mock for the types-only `mendix` package (its real entry throws).
+// Stays plain JS because it ships inside the consumer's node_modules, where
+// jest won't transform TypeScript. The JSDoc `@type` annotations check the
+// values against `mendix`'s types (repo-only, via test-config/tsconfig.json)
+// and are erased at runtime.
+
+/** @typedef {typeof import("mendix")} MendixModule */
+
+/**
+ * Map an enum's type to `{ [Member]: itsStringValue }`.
+ * @template E
+ * @typedef {{ [K in keyof E]: `${Extract<E[K], string>}` }} EnumMock
+ */
+
 module.exports = {
+    /** @type {EnumMock<MendixModule["ValueStatus"]>} */
     ValueStatus: {
         Available: "available",
         Unavailable: "unavailable",
         Loading: "loading"
     },
+    /** @type {EnumMock<MendixModule["FormatterType"]>} */
     FormatterType: {
         Number: "number",
         DateTime: "datetime"

packages/pluggable-widgets-tools/test-config/tsconfig.json

@@ -0,0 +1,10 @@
+{
+    "extends": "../configs/tsconfig.base",
+    "compilerOptions": {
+        "noEmit": true,
+        "allowJs": true,
+        "checkJs": true,
+        "moduleResolution": "bundler"
+    },
+    "include": ["__mocks__/mendix.js"]
+}