@giancosta86/more-jest

more-jest

TypeScript utilities for Jest

more-jest is a TypeScript library providing enhanced TypeScript support for Jest.

Installation

The package on NPM is:

@giancosta86/omnicourse

The public API entirely resides in the root package index, so you shouldn't reference specific modules.

Matchers

To use the matchers provided by more-jest within a project, one needs to:

1. Add the following attribute to the object exported by jest.config.js:

   setupFilesAfterEnv: ["@giancosta86/more-jest/dist/all"],

2. Add this line to a global.d.ts file within the project root directory:

   import "@giancosta86/more-jest";

3. Add "./global.d.ts" to the include array in tsconfig.json

Usage

Equality.addTesterFor(classType)

Takes a parameter of class T containing a method defined as:

equals(other: T): boolean {}

and registers into Jest an equality tester that:

• returns undefined if either equality operand is not an instance of class T

• otherwise, returns calls optionalEquals() as defined by @giancosta86/swanlake

Equality.test

Runs a suite of equality-related tests, inside a describe block having title «equality».

It takes the following parameters:

• a factory used to create a reference object and its equal copies

• a factory used to create a different object, not equal to the reference instance

Comparison.test

Runs a suite of comparison-related tests based on a Comp algorithm, within a «comparison» describe block.

It takes an object with the following parameters:

• comp: the Comp object to be tested

• scrambledItems: the items in any chaotic state

• sortedItems: the items in the expected order

Matchers

• .toBeTrimmed(): expects that a string be trimmed

• .toEqualSequence(expected): expects that an iterable has the same items, in the same order, as the given iterable. The iterables can be of different types

• .toHaveSameJson(expected): expects that a value be serialized to JSON as the given object

See also

• swan-lake

• more-jest-io - this library's I/O-related counterpart

• jest-extended - Additional Jest matchers