extra-jest

Some extra functions to work with jest testing framework

Requirements

• Node.js ≥ 8.9.0

APIs

NOTE:

• xjest is an alias of module extra-jest
• jsYaml is an alias of module js-yaml
• fsTreeUtils is an alias of module fs-tree-utils

xjest.snap.mkfn

type DumpFunction<X> = (x: X, options?: jsYaml.DumpOptions) => string
type TestFunction<X> = (x: X, options?: jsYaml.DumpOptions) => () => void

declare function mkfn<X> (fn: DumpFunction<X>, defaultOptions?: jsYaml.DumpOptions): TestFunction<X>

This function is used to created xjest.snap.* functions below.

xjest.snap.*

declare function unsafe (x: any, options?: jsYaml.DumpOptions): () => void
declare function safe (x: any, options?: jsYaml.DumpOptions): () => void
declare function pureSafe (x: any, options?: jsYaml.DumpOptions): () => void
declare function pureUnsafe (x: any, options?: jsYaml.DumpOptions): () => void
declare function noRefs (x: any, options?: jsYaml.DumpOptions): () => void

Create jest snapshots but in YAML format.

Features:

• xjest.snap.unsafe dumps JavaScript objects before writing to snapshot.
• xjest.snap.safe safely dumps JavaScript objects before writing to snapshot.
• xjest.snap.pureUnsafe is xjest.snap.unsafe without default options.
• xjest.snap.pureSafe is xjest.snap.safe without default options.
• xjest.snap.noRefs is xjest.snap.unsafe with self references.

Default Options:

namespace defaultOptions {
  export const skipInvalid = true
  export const sortKeys = true
  export const noRefs = false
  export const noCompatMode = true
}

xjest.setupTeardown.base.createFactory

type PromiseFunc<X, Y> = (x: X) => Promise<Y>
type SyncFunc<X, Y> = (x: X) => Y
type SetupFunc<Y> = () => Promise<Y>
type TeardownFunc<X> = (x: X) => Promise<void>
type CalledFunc<X, Y> = PromiseFunc<X, Y>
type SyncCalledFunc<X, Y> = SyncFunc<X, Y>
type Tester = () => Promise<void>
type AsyncTesterFactory<SM, MT> = (fn: CalledFunc<SM, MT>) => Tester
type SyncTesterFactory<SM, MT> = (fn: SyncCalledFunc<SM, MT>) => Tester

interface Config<SY, TX> {
  readonly setup: SetupFunc<SY>
  readonly teardown: TeardownFunc<TX>
}

type TesterFactory<SM, MT> = AsyncTesterFactory<SM, MT> & {
  forAsync: AsyncTesterFactory<SM, MT>,
  forSync: SyncTesterFactory<SM, MT>
}

declare function createFactory<SM, MT> (config: Config<SM, MT>): TesterFactory<SM, MT>

Creates a TesterFactory<SM, MT> from a config: Config<SM, MT>.

Parameters:

• config.setup: A function that runs before main test.
• config.teardown: A function that runs after main test.

Returns:

• A TesterFactory<SM, MT> is both a namespace and a function, it has the same effect as TesterFactory<SM, MT>::forAsync.
• A TesterFactory::forAsync is a function, it creates a Tester from fn: CalledFunc<SM, MT>.
• A TesterFactory::forSync is a function, it creates a Tester from fn: SyncCalledFunc<SM, MT>.
• A Tester can be passed into jest test functions as a test function (second argument).

Aliases:

• xjest.setupTeardown.createFactory
• xjest.setupTeardown.default

xjest.setupTeardown.virtualEnvironment.createFactory

interface Info {
  readonly tree: Tree.Write.Node
  readonly container: string
  readonly previousWorkingDirectory: string
}

interface Factory {
  readonly info: Info
  readonly apply: base.TesterFactory<Info, void>
}

declare function createFactory (tree: fsTreeUtils.Tree.Write.Node, container?: string): Factory

Parameters:

• tree: Specifies directory structure of target directory.
• container (optional): Intended target directory, default to random name in os.tmpdir() folder.

Returns:

• Factory::info: Contains some information that might be useful (see interface Info).
• Factory::apply: Takes an async function and returns a Tester.

xjest.snapSpawn.snap

type SpawnFunc = (argv: string[], options: SpawnSyncOptions) => SpawnSyncReturns<string | Buffer>
declare function snap (fn: SpawnFunc, argv?: string[], options?: SpawnSyncOptions): () => void

Create a function that creates a snapshot from result of process execution.

Parameters:

• fn: A function that calls spawnSync.
• argv (optional): Additional arguments.
• options (optional): Options to pass to spawnSync.
• snap (optional): Snap function to use.

Returns:

• A function that makes snapshots from process execution result.

Aliases:

• xjest.snapSpawn.snap.default

xjest.snapSpawn.snap.withCommand

Like xjest.snapSpawn.snap above but with command: string as the first parameter instead of fn: SpawnFunc.

License

MIT © Hoàng Văn Khải