> For the complete documentation index, see [llms.txt](https://docs.oxygenhq.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.oxygenhq.org/download-installation-start/modules/module-assert.md).

# assert

## contain

Asserts that the string value contains a substring.

**Parameters:**

| Name       | Type     | Description                                     |
| ---------- | -------- | ----------------------------------------------- |
| `actual`   | `String` | Actual value.                                   |
| `contains` | `String` | Verbatim string to be contained.                |
| `message`  | `String` | `optional` Message to throw if assertion fails. |

## equal

Asserts that two values are equal (non-strict equality).

**Parameters:**

| Name       | Type     | Description                                                          |
| ---------- | -------- | -------------------------------------------------------------------- |
| `actual`   | `Object` | Actual value.                                                        |
| `expected` | `Object` | Expected value. Either an object or a string prefixed with `regex:`. |
| `message`  | `String` | `optional` Message to throw if assertion fails.                      |

## fail

Fails test with the given message.

**Parameters:**

| Name      | Type     | Description                         |
| --------- | -------- | ----------------------------------- |
| `message` | `String` | `optional` Error message to return. |

## notEqual

Asserts that two values are not equal (non-strict inequality).

**Parameters:**

| Name       | Type     | Description                                                          |
| ---------- | -------- | -------------------------------------------------------------------- |
| `actual`   | `Object` | Actual value.                                                        |
| `expected` | `Object` | Expected value. Either an object or a string prefixed with `regex:`. |
| `message`  | `String` | `optional` Message to throw if assertion fails.                      |

## pass

Passes the test with the given message.

**Parameters:**

| Name      | Type     | Description                   |
| --------- | -------- | ----------------------------- |
| `message` | `String` | `optional` Message to return. |


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