moduleeslint-plugin-warp-drive/rules/template-always-use-request-content

Rule	🏷️	✨
template-always-use-request-content	🐞

TIP

This rule requires a template-aware parser. See Template Rules for setup.

<Request> is a component for declaratively resolving a request's idle / loading / cancelled / error / content states in a template. Using it without ever consuming the resolved result is usually a sign of an anti-pattern in which the result is instead being read indirectly, e.g. by re-fetching the same resource from the store elsewhere. This defeats the purpose of using <Request> to establish a resolution boundary in the first place.

This rule flags three situations for any <Request> element:

• No :content block, and no other named block (:idle, :loading, :error, :cancelled, :always, etc.) either. The request's outcome is entirely discarded.
• A :content block that does not capture the yielded result via a block param, e.g. <:content>...</:content>.
• A :content block that captures the yielded result but never references it anywhere within the block, e.g. <:content as |result|>...</:content> where result is unused.

The :content block's second yielded "state" param (used for things like state.refresh or state.isBackgroundReloading) is unrelated to this rule -- whether or not it's used has no effect on whether the rule reports a violation. The result may also be captured under any name you like; the rule doesn't care about the specific identifier, only whether it's referenced.

Incorrect Code

import { Request } from '@warp-drive/ember';

<template>
  {{! the result is discarded entirely: no :content block and no other block either }}
  <Request @request={{@request}}>
    <SomeUnrelatedMarkup />
  </Request>
</template>

import { Request } from '@warp-drive/ember';

<template>
  {{! the :content block never captures the yielded result }}
  <Request @request={{@request}}>
    <:content>
      <SomeUnrelatedMarkup />
    </:content>
  </Request>
</template>

import { Request } from '@warp-drive/ember';

<template>
  {{! `result` is captured but never used }}
  <Request @request={{@request}}>
    <:content as |result|>
      <SomeUnrelatedMarkup />
    </:content>
  </Request>
</template>

Correct Code

import { Request } from '@warp-drive/ember';

<template>
  <Request @request={{@request}}>
    <:content as |result|>
      <h1>{{result.title}}</h1>
    </:content>
  </Request>
</template>

import { Request } from '@warp-drive/ember';

<template>
  {{! the second "state" param may be used, unused, or omitted -- it's unrelated to this rule }}
  <Request @request={{@request}}>
    <:content as |result state|>
      <h1>{{result.title}}</h1>
      <button {{on "click" state.refresh}}>Refresh</button>
    </:content>
  </Request>
</template>

import { Request } from '@warp-drive/ember';

<template>
  {{! no :content block, but other named blocks are present, so the request isn't discarded }}
  <Request @request={{@request}}>
    <:idle></:idle>
    <:loading></:loading>
    <:error></:error>
  </Request>
</template>

Variables

• export=