template-no-only-default-slot.md

ember/template-no-only-default-slot

🔧 This rule is automatically fixable by the --fix CLI option.

Disallows using only the default slot when rendering content into a component.

The default slot (<:default>) is used to explicitly target the main content block of a component. However, when only the default slot is used — with no named slots — the extra syntax is redundant and unnecessary.

This rule disallows using only the default slot block when rendering content into a component. The preferred form is to pass the content directly, without the default slot wrapper.

Motivation

When a component has a single default block like this:

<template>
  <MyComponent>
    <:default>
      Hello!
    </:default>
  </MyComponent>
</template>

The <:default> adds no semantic value. It's simpler and clearer to write:

<template>
  <MyComponent>
    Hello!
  </MyComponent>
</template>

Explicit slot naming should only be used when multiple slots are present, and disambiguation is needed.

Examples

This rule forbids the following:

<template>
  <MyComponent>
    <:default>
      What?
    </:default>
  </MyComponent>
</template>

<template>
  <MyComponent>
    <:default>
      <p>Hello world</p>
    </:default>
  </MyComponent>
</template>

This rule allows the following:

<template>
  <MyComponent>
    Hello!
  </MyComponent>
</template>

<template>
  <MyComponent>
    <:header>Header</:header>
    <:default>Content</:default>
  </MyComponent>
</template>

Migration

If you see this pattern:

<SomeCard>
  <:default>
    Card Content
  </:default>
</SomeCard>

Just remove the <:default> wrapper:

<SomeCard>
  Card Content
</SomeCard>

References

• Ember Guides - Named Blocks