* `operator` {string} The `operator` property on the error instance.

* `stackStartFn` {Function} If provided, the generated stack trace omits

frames before this function.

* `diff` {string} If set to `'full'`, shows the full diff in assertion errors. Defaults to `'simple'`.

Accepted values: `'simple'`, `'full'`.

A subclass of {Error} that indicates the failure of an assertion.

}

```

## Class: `assert.Assert`

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added: REPLACEME

-->

The `Assert` class allows creating independent assertion instances with custom options.

### `new assert.Assert([options])`

* `options` {Object}

* `diff` {string} If set to `'full'`, shows the full diff in assertion errors. Defaults to `'simple'`.

Accepted values: `'simple'`, `'full'`.

* `strict` {boolean} If set to `true`, non-strict methods behave like their

corresponding strict methods. Defaults to `true`.

Creates a new assertion instance. The `diff` option controls the verbosity of diffs in assertion error messages.

```js

const { Assert } = require('node:assert');

const assertInstance = new Assert({ diff: 'full' });

assertInstance.deepStrictEqual({ a: 1 }, { a: 2 });

// Shows a full diff in the error message.

```

**Important**: When destructuring assertion methods from an `Assert` instance,

the methods lose their connection to the instance's configuration options (such as `diff` and `strict` settings).

The destructured methods will fall back to default behavior instead.

```js

const myAssert = new Assert({ diff: 'full' });

// This works as expected - uses 'full' diff

myAssert.strictEqual({ a: 1 }, { b: { c: 1 } });

// This loses the 'full' diff setting - falls back to default 'simple' diff

const { strictEqual } = myAssert;

strictEqual({ a: 1 }, { b: { c: 1 } });

```

When destructured, methods lose access to the instance's `this` context and revert to default assertion behavior

(diff: 'simple', non-strict mode).

To maintain custom options when using destructured methods, avoid

destructuring and call methods directly on the instance.

## Class: `assert.CallTracker`

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