-
Notifications
You must be signed in to change notification settings - Fork 138
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
feat: new no-wait-for-snapshot rule (#223)
Closes: #214
- Loading branch information
Showing
6 changed files
with
404 additions
and
0 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,56 @@ | ||
# Ensures no snapshot is generated inside of a `wait` call' (no-wait-for-snapshot) | ||
|
||
Ensure that no calls to `toMatchSnapshot` or `toMatchInlineSnapshot` are made from within a `waitFor` method (or any of the other async utility methods). | ||
|
||
## Rule Details | ||
|
||
The `waitFor()` method runs in a timer loop. So it'll retry every n amount of time. | ||
If a snapshot is generated inside the wait condition, jest will generate one snapshot per loop. | ||
|
||
The problem then is the amount of loop ran until the condition is met will vary between different computers (or CI machines). This leads to tests that will regenerate a lot of snapshots until the condition is matched when devs run those tests locally updating the snapshots; e.g devs cannot run `jest -u` locally or it'll generate a lot of invalid snapshots who'll fail during CI. | ||
|
||
Note that this lint rule prevents from generating a snapshot from within any of the [async utility methods](https://testing-library.com/docs/dom-testing-library/api-async). | ||
|
||
Examples of **incorrect** code for this rule: | ||
|
||
```js | ||
const foo = async () => { | ||
// ... | ||
await waitFor(() => expect(container).toMatchSnapshot()); | ||
// ... | ||
}; | ||
|
||
const bar = async () => { | ||
// ... | ||
await waitFor(() => expect(container).toMatchInlineSnapshot()); | ||
// ... | ||
}; | ||
|
||
const baz = async () => { | ||
// ... | ||
await wait(() => { | ||
expect(container).toMatchSnapshot(); | ||
}); | ||
// ... | ||
}; | ||
``` | ||
|
||
Examples of **correct** code for this rule: | ||
|
||
```js | ||
const foo = () => { | ||
// ... | ||
expect(container).toMatchSnapshot(); | ||
// ... | ||
}; | ||
|
||
const bar = () => { | ||
// ... | ||
expect(container).toMatchInlineSnapshot(); | ||
// ... | ||
}; | ||
``` | ||
|
||
## Further Reading | ||
|
||
- [Async Utilities](https://testing-library.com/docs/dom-testing-library/api-async) |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,132 @@ | ||
import { ESLintUtils, TSESTree } from '@typescript-eslint/experimental-utils'; | ||
import { getDocsUrl, ASYNC_UTILS, LIBRARY_MODULES } from '../utils'; | ||
import { | ||
findClosestCallExpressionNode, | ||
isMemberExpression, | ||
} from '../node-utils'; | ||
|
||
export const RULE_NAME = 'no-wait-for-snapshot'; | ||
export type MessageIds = 'noWaitForSnapshot'; | ||
type Options = []; | ||
|
||
const ASYNC_UTILS_REGEXP = new RegExp(`^(${ASYNC_UTILS.join('|')})$`); | ||
const SNAPSHOT_REGEXP = /^(toMatchSnapshot|toMatchInlineSnapshot)$/; | ||
|
||
export default ESLintUtils.RuleCreator(getDocsUrl)<Options, MessageIds>({ | ||
name: RULE_NAME, | ||
meta: { | ||
type: 'problem', | ||
docs: { | ||
description: | ||
'Ensures no snapshot is generated inside of a `waitFor` call', | ||
category: 'Best Practices', | ||
recommended: 'warn', | ||
}, | ||
messages: { | ||
noWaitForSnapshot: | ||
"A snapshot can't be generated inside of a `{{ name }}` call", | ||
}, | ||
fixable: null, | ||
schema: [], | ||
}, | ||
defaultOptions: [], | ||
|
||
create(context) { | ||
const asyncUtilsUsage: Array<{ | ||
node: TSESTree.Identifier | TSESTree.MemberExpression; | ||
name: string; | ||
}> = []; | ||
const importedAsyncUtils: string[] = []; | ||
const snapshotUsage: TSESTree.Identifier[] = []; | ||
|
||
return { | ||
'ImportDeclaration > ImportSpecifier,ImportNamespaceSpecifier'( | ||
node: TSESTree.Node | ||
) { | ||
const parent = node.parent as TSESTree.ImportDeclaration; | ||
|
||
if (!LIBRARY_MODULES.includes(parent.source.value.toString())) return; | ||
|
||
let name; | ||
if (node.type === 'ImportSpecifier') { | ||
name = node.imported.name; | ||
} | ||
|
||
if (node.type === 'ImportNamespaceSpecifier') { | ||
name = node.local.name; | ||
} | ||
|
||
importedAsyncUtils.push(name); | ||
}, | ||
[`CallExpression > Identifier[name=${ASYNC_UTILS_REGEXP}]`]( | ||
node: TSESTree.Identifier | ||
) { | ||
asyncUtilsUsage.push({ node, name: node.name }); | ||
}, | ||
[`CallExpression > MemberExpression > Identifier[name=${ASYNC_UTILS_REGEXP}]`]( | ||
node: TSESTree.Identifier | ||
) { | ||
const memberExpression = node.parent as TSESTree.MemberExpression; | ||
const identifier = memberExpression.object as TSESTree.Identifier; | ||
const memberExpressionName = identifier.name; | ||
|
||
asyncUtilsUsage.push({ | ||
node: memberExpression, | ||
name: memberExpressionName, | ||
}); | ||
}, | ||
[`Identifier[name=${SNAPSHOT_REGEXP}]`](node: TSESTree.Identifier) { | ||
snapshotUsage.push(node); | ||
}, | ||
'Program:exit'() { | ||
const testingLibraryUtilUsage = asyncUtilsUsage.filter(usage => { | ||
if (isMemberExpression(usage.node)) { | ||
const object = usage.node.object as TSESTree.Identifier; | ||
|
||
return importedAsyncUtils.includes(object.name); | ||
} | ||
|
||
return importedAsyncUtils.includes(usage.name); | ||
}); | ||
|
||
function getClosestAsyncUtil( | ||
asyncUtilUsage: { | ||
node: TSESTree.Identifier | TSESTree.MemberExpression; | ||
name: string; | ||
}, | ||
node: TSESTree.Node | ||
) { | ||
let callExpression = findClosestCallExpressionNode(node); | ||
while (callExpression != null) { | ||
if (callExpression.callee === asyncUtilUsage.node) | ||
return asyncUtilUsage; | ||
callExpression = findClosestCallExpressionNode( | ||
callExpression.parent | ||
); | ||
} | ||
return null; | ||
} | ||
|
||
snapshotUsage.forEach(node => { | ||
testingLibraryUtilUsage.forEach(asyncUtilUsage => { | ||
const closestAsyncUtil = getClosestAsyncUtil(asyncUtilUsage, node); | ||
if (closestAsyncUtil != null) { | ||
let name; | ||
if (isMemberExpression(closestAsyncUtil.node)) { | ||
name = (closestAsyncUtil.node.property as TSESTree.Identifier) | ||
.name; | ||
} else { | ||
name = closestAsyncUtil.name; | ||
} | ||
context.report({ | ||
node, | ||
messageId: 'noWaitForSnapshot', | ||
data: { name }, | ||
}); | ||
} | ||
}); | ||
}); | ||
}, | ||
}; | ||
}, | ||
}); |
Oops, something went wrong.