# ember/template-require-strict-mode

> **HBS Only**: This rule applies to classic `.hbs` template files only (loose mode). It is not relevant for `gjs`/`gts` files (strict mode), where these patterns cannot occur.

<!-- end auto-generated rule header -->

Require templates to be in strict mode.

Ember's Polaris edition component authoring format is template tag, which makes
templates follow "strict mode" semantics.

This rule requires all templates to use strict mode (template tag). Effectively this
means you may only have template content in `.gjs`/`.gts` files, not in `.hbs` or
`.js`/`.ts`.

## Examples

This rule **forbids** the following:

```hbs
// button.hbs
<button>{{yield}}</button>
```

```js
// button-test.js
import { hbs } from 'ember-cli-htmlbars';

test('it renders', async (assert) => {
  await render(hbs`<Button>Ok</Button>`);
  // ...
});
```

This rule **allows** the following:

```gjs
// button.gjs
<template>
  <button>{{yield}}</button>
</template>
```

```gjs
// button-test.gjs
import { Button } from 'ember-awesome-button';

test('it renders', async (assert) => {
  await render(<template><Button>Ok</Button></template>);
  // ..
});
```

## References

- [Template Tag Guide](https://guides.emberjs.com/release/components/template-tag-format/)
- [Strict Mode RFC](https://rfcs.emberjs.com/id/0496-handlebars-strict-mode/)