34 lines
612 B
Markdown
34 lines
612 B
Markdown
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# Suggest using `toBeNull()` (`prefer-to-be-null`)
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In order to have a better failure message, `toBeNull()` should be used upon
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asserting expectations on null value.
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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 a null value.
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```js
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expect(null).toBe(null);
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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(null).toBe(null);
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expect(null).toEqual(null);
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expect(null).toStrictEqual(null);
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```
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The following pattern is not warning:
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```js
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expect(null).toBeNull();
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```
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