Angular (TypeScript) : Error when use "ng test" | Karma/Jasmine : AssertionError [ERR_ASSERTION]: Compilation cannot be undefined

Question

I use Angular (TypeScript)

• Angular 15.1.0
• Node version : 19.7.0
• npm : 9.5.1

I have an error when i use ng test :

The error :

⠙ Generating browser application bundles (phase: setup)...node:internal/process/promises:289
            triggerUncaughtException(err, true /* fromPromise */);
            ^

AssertionError [ERR_ASSERTION]: Compilation cannot be undefined.
    at webpackOptions.entry (/Users/***/Documents/folder/node_modules/@angular-devkit/build-angular/src/builders/karma/find-tests-plugin.js:70:38) {
  generatedMessage: false,
  code: 'ERR_ASSERTION',
  actual: undefined,
  expected: true,
  operator: '=='
}

My package.json

{
  "name": "epic-trip-app",
  "version": "0.0.0",
  "scripts": {
    "ng": "ng",
    "start": "ng serve",
    "build": "ng build",
    "watch": "ng build --watch --configuration development",
    "test": "jasmine"
  },
  "private": true,
  "dependencies": {
    "@angular/animations": "^15.1.0",
    "@angular/cdk": "~15.1.5",
    "@angular/common": "^15.1.0",
    "@angular/compiler": "^15.1.0",
    "@angular/core": "^15.1.0",
    "@angular/forms": "^15.1.0",
    "@angular/material": "~15.1.5",
    "@angular/platform-browser": "^15.1.0",
    "@angular/platform-browser-dynamic": "^15.1.0",
    "@angular/router": "^15.1.0",
    "@datorama/akita": "^8.0.1",
    "karma-coverage": "^2.2.0",
    "karma-jasmine-html-reporter": "^2.0.0",
    "karma-spec-reporter": "^0.0.36",
    "karma-typescript-mock": "^1.0.1",
    "rxjs": "~7.8.0",
    "tslib": "^2.3.0",
    "typescript-core": "^9.2.0",
    "zone.js": "~0.12.0"
  },
  "devDependencies": {
    "@angular-devkit/build-angular": "^15.1.6",
    "@angular/cli": "~15.1.6",
    "@angular/compiler-cli": "^15.1.0",
    "@types/jasmine": "~4.3.0",
    "jasmine": "^4.5.0",
    "jasmine-core": "~4.5.0",
    "jasmine-ts": "^0.4.0",
    "karma": "^6.1.0",
    "karma-chrome-launcher": "^3.1.1",
    "karma-jasmine": "^5.1.0",
    "karma-typescript": "^5.5.3",
    "ts-node": "^10.9.1",
    "typescript": "~4.9.4"
  }
}

My angular.json

{
  "$schema": "./node_modules/@angular/cli/lib/config/schema.json",
  "version": 1,
  "newProjectRoot": "projects",
  "projects": {
    "EpicTripApp": {
      "projectType": "application",
      "schematics": {
        "@schematics/angular:component": {
          "style": "scss",
          "skipTests": true
        }
      },
      "root": "",
      "sourceRoot": "src",
      "prefix": "app",
      "architect": {
        "build": {
          "builder": "@angular-devkit/build-angular:browser",
          "options": {
            "outputPath": "dist/epic-trip-app",
            "index": "src/index.html",
            "main": "src/main.ts",
            "polyfills": [
              "zone.js"
            ],
            "tsConfig": "tsconfig.app.json",
            "inlineStyleLanguage": "scss",
            "assets": [
              "src/favicon.ico",
              "src/assets"
            ],
            "styles": [
              "@angular/material/prebuilt-themes/indigo-pink.css",
              "src/styles.scss",
              "src/theme.scss"
            ],
            "scripts": []
          },
          "configurations": {
            "production": {
              "budgets": [
                {
                  "type": "initial",
                  "maximumWarning": "500kb",
                  "maximumError": "1mb"
                },
                {
                  "type": "anyComponentStyle",
                  "maximumWarning": "2kb",
                  "maximumError": "4kb"
                }
              ],
              "outputHashing": "all"
            },
            "development": {
              "buildOptimizer": false,
              "optimization": false,
              "vendorChunk": true,
              "extractLicenses": false,
              "sourceMap": true,
              "namedChunks": true
            }
          },
          "defaultConfiguration": "production"
        },
        "serve": {
          "builder": "@angular-devkit/build-angular:dev-server",
          "configurations": {
            "production": {
              "browserTarget": "EpicTripApp:build:production"
            },
            "development": {
              "browserTarget": "EpicTripApp:build:development"
            }
          },
          "defaultConfiguration": "development"
        },
        "extract-i18n": {
          "builder": "@angular-devkit/build-angular:extract-i18n",
          "options": {
            "browserTarget": "EpicTripApp:build"
          }
        },
        "test": {
          "builder": "@angular-devkit/build-angular:karma",
          "options": {
            "polyfills": [
              "zone.js",
              "zone.js/testing"
            ],
            "tsConfig": "tsconfig.spec.json",
            "inlineStyleLanguage": "scss",
            "assets": [
              "src/favicon.ico",
              "src/assets"
            ],
            "styles": [
              "@angular/material/prebuilt-themes/indigo-pink.css",
              "src/styles.scss"
            ],
            "scripts": [],
            "karmaConfig": "karma.conf.js"
          }
        }
      }
    }
  },
  "cli": {
    "analytics": "b1288342-9e70-43a2-9613-00151ad6c303"
  }
}

Answer 1

I found the solution. The problem was in the Angular.json "skipTests": true . I just remove it. and I update some packages

Angular.json

{
  "$schema": "./node_modules/@angular/cli/lib/config/schema.json",
  "version": 1,
  "newProjectRoot": "projects",
  "projects": {
    "EpicTripApp": {
      "projectType": "application",
      "schematics": {
        "@schematics/angular:component": {
          "style": "scss",
          "skipTests": true  <--**HERE**
        }
      }
...