34 lines
674 B
Markdown
34 lines
674 B
Markdown
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# Suggest using `toHaveLength()` (`prefer-to-have-length`)
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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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### Default configuration
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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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