fix jest and cypress global type definitions clashing in IntelliJ

src/tsconfig.spec.json

@@ -0,0 +1,21 @@
+/* To learn more about this file see: https://angular.io/config/tsconfig. */
+{
+  "extends": "../tsconfig.json",
+  "compilerOptions": {
+    "outDir": "./out-tsc/spec",
+    "module": "CommonJs",
+    "skipLibCheck": true,
+    "emitDecoratorMetadata": true
+  },
+  "files": [
+    "polyfills.ts"
+  ],
+  "include": [
+    "**/*.spec.ts",
+  ],
+  "exclude": [
+    // This is to prevent global types clashing between jest and cypress
+    // See: https://github.com/cypress-io/cypress/issues/22059#issuecomment-1148921141
+    "../cypress.config.ts",
+  ]
+}

tsconfig.spec.json

@@ -1,17 +1,11 @@
-/* To learn more about this file see: https://angular.io/config/tsconfig. */
+/* Having the real tsconfig.spec.json under src is a workaround, as in IntelliJ,
+ * the *.spec.ts files would otherwise be compiled with tsconfig.app.json,
+ * which would lead to a clash of global types for tests that both cypress and jest define.
+ *
+ * See:
+ * - https://stackoverflow.com/questions/58999086/cypress-causing-type-errors-in-jest-assertions/72663546#72663546
+ * - https://youtrack.jetbrains.com/issue/WEB-43373/IntelliJ-not-correctly-interpreting-standard-ng-cli-tsconfig-setup
+ */
 {
-  "extends": "./tsconfig.json",
-  "compilerOptions": {
-    "outDir": "./out-tsc/spec",
-    "module": "CommonJs",
-    "types": ["jest"],
-    "skipLibCheck": true,
-    "emitDecoratorMetadata": true
-  },
-  "files": ["src/polyfills.ts"],
-  "include": [
-    "src/**/*.spec.ts",
-    "src/**/*.d.ts",
-    "../node_modules/@types/jest"
-  ]
+  "extends": "./src/tsconfig.spec.json"
 }