Unbound | Testing Native Code

Testing Native Code

Fake the platform and native bridges in tests.

Fakes for a plugin that calls the native bridge, from native in @unbound-app/api/testing. Set up the preset first: see Writing Tests.

Example

Set the platform, modules and capabilities:

import { native } from '@unbound-app/api/testing';

native.setPlatform('android');
native.registerModule('NativeFileModule', { readFile: async () => '' });
native.setCapabilities(['native.java.hooks']);

startPlugin gives context.native.objc on iOS, and context.native.java and hooks on Android. Register the classes your handlers reach:

import { native, startPlugin } from '@unbound-app/api/testing';

native.objc.registerClass('UIView', {
	superclass: 'NSObject',
	methods: { 'setAlpha:': (self, alpha) => {}, 'tag': () => 7 },
	classMethods: { sharedView: () => native.objc.create('UIView') },
});
await startPlugin();

native.setPlatform('android');
native.java.registerClass('android.view.View', {
	methods: { getWidth: () => 120 },
	fields: { mLeft: 4 },
	staticMethods: { create: () => native.java.create('android.view.View') },
	staticFields: { INSTANCE: native.java.create('android.view.View') },
});

Reference

Call	Does
`native.setPlatform(platform)`	Sets the platform, `'ios'` by default. `Platform.OS` follows it
`native.registerModule(name, module)`	A module for `getNativeModule(name)` to return
`native.setCapabilities(capabilities)`	What `native.has` reports
`native.objc.registerClass(name, { superclass?, methods?, classMethods? })`	Adds a class. A method gets the object and the call's arguments; `callSuper` reaches the superclass
`native.objc.create(name, ivars?)`	An object, with the instance variables `getIvar` reads
`native.java.registerClass(name, options)`	Adds a class. See Java Classes
`native.java.create(name, fields?)`	An object, as a `handle` value
`native.calls`	Every `objc`, `java` and `hooks` call this test: `bridge`, `method`, `target` class, `name` (selector or method), `args`

Java Classes

native.java.registerClass options: superclass, methods, staticMethods, fields, staticFields, signatures, fieldTypes, construct.

A method gets the object and plain arguments, and returns a plain value. The bridge tags it string, int, double, boolean, null, handle or array.
construct runs for java.construct.
signatures gives each method's { parameters?, returnType? }, and fieldTypes each field's type. java.describe returns them, so code that finds a member by its types works. Unset types are java.lang.Object.

Platform Handlers

definePlatform picks the current platform's handler, and throws NativeBridgeUnsupportedPlatformError when there is none.
It runs at import, before a test sets the platform. A function handler therefore calls the current platform's handler on each call. Any other handler is read once, when definePlatform runs.
getNativeModule(...names) returns the first module registered under one of the names.

Faked Members

Bridge	Faked
`objc`	`getClass`, `alloc`, `create`, `className`, `respondsTo`, `call`, `invoke`, `invokeAsync`, `callSuper`, `invokeSuper`, `batch`, `prepare`, `invokePrepared`, `getIvar`, `setIvar`, associated objects, `struct`, `hook`
`java`	`getClass`, `construct`, `describe`, `className`, `respondsTo`, `invoke`, `invokeAsync`, `getField`, `setField`, `batch`, `batchAsync`, `prepare`, `invokePrepared`, associated objects, `release`
`hooks`	`hook`, `remove`, return values