| layout | page-api | |
|---|---|---|
| title | QUnit.config.seed | |
| excerpt | Enable randomized ordering of tests. | |
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| version_added | 1.23.0 |
Enable randomized ordering of tests.
| type | `string` or `boolean` or `undefined` |
|---|---|
| default | `undefined` |
This option is also available as [CLI option](../../cli.md), and as URL query parameter in the browser.
When set to boolean true, or a string, QUnit will run tests in a seeded-random order.
The provided string will be used as the seed in a pseudo-random number generator to ensure that results are reproducible. The randomization will also respect the reorder option if enabled and re-run failed tests first without randomizing them.
Randomly ordering your tests can help identify non-atomic tests which either depend on a previous test or are leaking state to subsequent tests.
If seed is boolean true (or set as URL query parameter without a value), then QUnit will generate on-demand a new random value to use as seed. You can then read the seed at runtime from the configuration value, and use it to reproduce the same test sequence later.