CallTracker

[<Interface>]
type CallTracker =
    abstract member calls<'Func> (?fn: 'Func, ?exact: float) : 'Func
    abstract member calls (?exact: float) : unit -> unit
    abstract member getCalls (fn: Function) : CallTrackerCall array
    abstract member report () : CallTrackerReportInformation array
    abstract member reset (?fn: Function) : unit
    abstract member verify () : unit


Assembly	`Xantham.Fable.Node`

This feature is deprecated and will be removed in a future version. Please consider using alternatives such as the mock helper function.

@since v14.2.0, v12.19.0

Methods

abstract member calls<'Func> (?fn: 'Func, ?exact: float) : 'Func

The wrapper function is expected to be called exactly exact times. If the function has not been called exactly exact times when tracker.verify() is called, then tracker.verify() will throw an error.

import assert from 'node:assert';

// Creates call tracker.
const tracker = new assert.CallTracker();

function func() {}

// Returns a function that wraps func() that must be called exact times
// before tracker.verify().
const callsfunc = tracker.calls(func);

@since v14.2.0, v12.19.0

Returns. A function that wraps fn.

abstract member calls (?exact: float) : unit -> unit

import assert from 'node:assert';

// Creates call tracker.
const tracker = new assert.CallTracker();

function func() {}

// Returns a function that wraps func() that must be called exact times
// before tracker.verify().
const callsfunc = tracker.calls(func);

@since v14.2.0, v12.19.0

Returns. A function that wraps fn.

abstract member getCalls (fn: Function) : CallTrackerCall array

Example:

import assert from 'node:assert';

const tracker = new assert.CallTracker();

function func() {}
const callsfunc = tracker.calls(func);
callsfunc(1, 2, 3);

assert.deepStrictEqual(tracker.getCalls(callsfunc),
[{ thisArg: undefined, arguments: [1, 2, 3] }]);

@since v18.8.0, v16.18.0

Returns. An array with all the calls to a tracked function.

abstract member report () : CallTrackerReportInformation array

The arrays contains information about the expected and actual number of calls of the functions that have not been called the expected number of times.

import assert from 'node:assert';

// Creates call tracker.
const tracker = new assert.CallTracker();

function func() {}

// Returns a function that wraps func() that must be called exact times
// before tracker.verify().
const callsfunc = tracker.calls(func, 2);

// Returns an array containing information on callsfunc()
console.log(tracker.report());
// [
//  {
//    message: 'Expected the func function to be executed 2 time(s) but was
//    executed 0 time(s).',
//    actual: 0,
//    expected: 2,
//    operator: 'func',
//    stack: stack trace
//  }
// ]

@since v14.2.0, v12.19.0

Returns. An array of objects containing information about the wrapper functions returned by {@link tracker.calls()}.

abstract member reset (?fn: Function) : unit

Reset calls of the call tracker. If a tracked function is passed as an argument, the calls will be reset for it. If no arguments are passed, all tracked functions will be reset.

import assert from 'node:assert';

const tracker = new assert.CallTracker();

function func() {}
const callsfunc = tracker.calls(func);

callsfunc();
// Tracker was called once
assert.strictEqual(tracker.getCalls(callsfunc).length, 1);

tracker.reset(callsfunc);
assert.strictEqual(tracker.getCalls(callsfunc).length, 0);

@since v18.8.0, v16.18.0

Parameter
`fn`	a tracked function to reset.

abstract member verify () : unit

Iterates through the list of functions passed to tracker.calls () and will throw an error for functions that have not been called the expected number of times.

import assert from 'node:assert';

// Creates call tracker.
const tracker = new assert.CallTracker();

function func() {}

// Returns a function that wraps func() that must be called exact times
// before tracker.verify().
const callsfunc = tracker.calls(func, 2);

callsfunc();

// Will throw an error since callsfunc() was only called once.
tracker.verify();

@since v14.2.0, v12.19.0