Angular 10–Strict mode

With the release of Angular 10 a more strict project setup is available. You can enable this by adding a –strict flag when creating a new Angular project:

ng new --strict

This strict mode allows to have more build-time optimizations, help to catch bugs faster and improves overall maintainability of your Angular application.

Therefore it applies the following changes:

• Enables strict mode in TypeScript
• Turns template type checking to Strict
• Default bundle budgets have been reduced by ~75%
• Configures linting rules to prevent declarations of type any
• Configures your app as side-effect free to enable more advanced tree-shaking

There is no out-of-the box option to enable this for an existing project(after creating it without the –strict flag or after upgrading from a previous version) but you can apply the same changes manually:

• Add the following rules to your tsconfig.json:

"compilerOptions": {
  "strict": true,
  "forceConsistentCasingInFileNames": true,
  "noFallthroughCasesInSwitch": true
},
"angularCompilerOptions": {
  "strictInjectionParameters": true,
  "strictInputAccessModifiers": true,
  "strictTemplates": true
}   

• Update the tslint.json:

"no-any": true

• Update the bundle budget sizes in your angular.json:

"configurations": {
  "production": {
    "budgets": [
      {
        "type": "initial",
        "maximumWarning": "500kb",
        "maximumError": "1mb",
      },
      {
        "type": "anyComponentStyle",
        "maximumWarning": "2kb",
        "maximumError": "4kb",
      },
    ]
  }
}

• Add a schematics to your projects.[projectName].schematics path in the angular.json:

schematics: {
  "@schematics/angular:application": {
    "strict": true
  }
}

    

More information: https://blog.angular.io/angular-cli-strict-mode-c94ba5965f63