40 lines
986 B
Markdown
40 lines
986 B
Markdown
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# Suggest using `toHaveLength()` (`prefer-to-have-length`)
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💼 This rule is enabled in the 🎨 `style`
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[config](https://github.com/jest-community/eslint-plugin-jest/blob/main/README.md#shareable-configurations).
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🔧 This rule is automatically fixable by the
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[`--fix` CLI option](https://eslint.org/docs/latest/user-guide/command-line-interface#--fix).
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<!-- end auto-generated rule header -->
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In order to have a better failure message, `toHaveLength()` should be used upon
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asserting expectations on objects length property.
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## Rule details
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This rule triggers a warning if `toBe()`, `toEqual()` or `toStrictEqual()` is
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used to assert objects length property.
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```js
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expect(files.length).toBe(1);
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```
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This rule is enabled by default.
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The following patterns are considered warnings:
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```js
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expect(files.length).toBe(1);
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expect(files.length).toEqual(1);
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expect(files.length).toStrictEqual(1);
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```
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The following pattern is not warning:
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```js
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expect(files).toHaveLength(1);
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```
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