chore(tests): Convert jest config to js

Which seems to speed up the tests execution.

hyperfine --warmup 5 --prepare "nx reset && nx clear-cache" \
                    --runs 100 "nx run-many -t lint"
  Time (mean ± σ):    1.417s ±  0.053s  [User: 0.887s, System: 0.113s]
  Range (min … max):  1.368s …  1.775s  100 runs

hyperfine --warmup 5 --prepare "nx reset && nx clear-cache" \
                    --runs 100 "nx run-many -t build"
  Time (mean ± σ):    2.110s ±  0.021s  [User: 2.571s, System: 0.216s]
  Range (min … max):  2.078s …  2.193s  100 runs

hyperfine --warmup 5 --prepare "nx reset && nx clear-cache" \
                    --runs 100 "nx run-many -t test"
  Time (mean ± σ):    1.493s ±  0.010s  [User: 0.787s, System: 0.134s]
  Range (min … max):  1.460s …  1.540s  100 runs

apps/app/jest.config.js

@@ -0,0 +1,25 @@
+let jestConfigObject = {
+  displayName: 'app',
+  preset: '../../jest.preset.js',
+  testEnvironment: 'node',
+  transform: {
+    '^.+\\.[tj]s$': ['ts-jest', { tsconfig: '<rootDir>/tsconfig.spec.json' }]
+  },
+  moduleFileExtensions: ['ts', 'js', 'html'],
+  coverageDirectory: '../../coverage/apps/app'
+}
+
+if (process.env.NODE_ENV === 'CI' || process.env.CI === 'true') {
+  jestConfigObject.transform = {
+    '^.+\\.[tj]s$': [
+      'ts-jest',
+      {
+        tsconfig: '<rootDir>/tsconfig.spec.json',
+        isolatedModules: true,
+        diagnostics: false
+      }
+    ]
+  }
+}
+
+module.exports = jestConfigObject

apps/app/tsconfig.app.json

@@ -7,6 +7,6 @@
     "emitDecoratorMetadata": true,
     "target": "es2021"
   },
-  "exclude": ["jest.config.ts", "src/**/*.spec.ts", "src/**/*.test.ts"],
+  "exclude": ["jest.config.js", "src/**/*.spec.ts", "src/**/*.test.ts"],
   "include": ["src/**/*.ts"]
 }

apps/app/tsconfig.spec.json

@@ -6,7 +6,7 @@
     "types": ["jest", "node"]
   },
   "include": [
-    "jest.config.ts",
+    "jest.config.js",
     "src/**/*.test.ts",
     "src/**/*.spec.ts",
     "src/**/*.d.ts"

jest.config.js

@@ -0,0 +1,7 @@
+process.env.TZ = 'UTC'
+
+const { getJestProjectsAsync } = require('@nx/jest')
+
+module.exports = {
+  projects: await getJestProjectsAsync()
+}