components/internal/mdctest/test_helpers.go

package mdctest // import "github.com/vecty-components/material/components/internal/mdctest"

import (
	"syscall/js"

	"github.com/vecty-components/material/gojs"
	"github.com/vecty-components/material/gojs/jsdom"
)

const (
	MCW_MODULE = "material-components-web/dist/material-components-web"
)

var (
	Dom jsdom.JSDOM
)

func Init() error {
	err := LoadMDCModule()
	if err != nil {
		return err
	}

	Dom, err = EmulateDOM()
	if err != nil {
		return err
	}

	err = ShimHyperform()
	if err != nil {
		return err
	}

	return nil
}

// For some reason the material-components-web node module does not come with
// MDCMenu, it only comes with an undocumented MDCSimpleMenu.
func InitMenu() (err error) {
	gojs.CatchException(&err)
	mdc := js.Global().Get("Object").New()
	mdc.Set("menu", js.Global().Call("require", "@material/menu/dist/mdc.menu"))
	js.Global().Set("mdc", mdc)

	Dom, err = EmulateDOM()
	if err != nil {
		return err
	}

	return err
}

func LoadMDCModule() (err error) {
	gojs.CatchException(&err)
	js.Global().Set("mdc", js.Global().Call("require", MCW_MODULE))
	return err
}

func ShimHyperform() (err error) {
	gojs.CatchException(&err)
	js.Global().Call("require", "hyperform").Invoke(js.Global().Get("window"))
	return err
}

// EmulateDOM sets up a fake DOM in Node for "gopherjs test" We emulate a
// browser dom since tests run in Node, and MDC components need a dom element to
// attach to.  This is not needed when running in a browser.
func EmulateDOM() (dom jsdom.JSDOM, err error) {
	dom, err = jsdom.New(``, &jsdom.M{"pretendToBeVisual": true})
	if err != nil {
		return nil, err
	}
	dom.SetHTML(`<html><body></body></html>`)
	js.Global().Set("window", dom.Window())
	js.Global().Set("document", dom.Window().Get("document"))
	js.Global().Set("HTMLElement", dom.Window().Get("HTMLElement"))
	raf := dom.Window().Get("requestAnimationFrame")
	js.Global().Set("requestAnimationFrame", raf)
	caf := dom.Window().Get("cancelAnimationFrame")
	js.Global().Set("cancelAnimationFrame", caf)
	gcs := dom.Window().Get("getComputedStyle")
	js.Global().Set("getComputedStyle", gcs)
	return dom, err
}