Browser integration testing helpers

[jackc]

I'm using rod for browser integration testing its performance is excellent. With a little bit of wrapper logic I'm able to spin up multiple sets of database, application server, and rod controlled browser to run my tests in parallel. It runs much faster than what I used to do in Capybara.

However, I'm missing some of the conveniences that Capybara and Ruby provided.

Default timeouts per action. I set a timeout for the entire test but it doesn't appear there is any way to automatically set a short timeout for each action. e.g. I have a 30 second timeout for the entire test. But when an expected element is missing early in a test I still have to wait the full 30 seconds for it to fail. I would like to wait a few seconds then give up without having to manually call Timeout for each MustElement.

Must... methods cause a panic instead of a test failure. This means test output is a stack trace where it is difficult to quickly see on what line the failure occurred. I'd rather get a normal test failure with a message like could not find element with selector ....

Every method being prefixed by Must is a bit ugly too.

---

I'm considering writing wrappers around the core types like Page and Element so I can do something like the following:

func TestFeature(t *testing.T) {
	browser := rod.New().MustConnect()
	defer browser.MustClose()

	page := BrowserTest(t, browser)
	page.Element("a", "New").Click()
	page.Element("textarea").SelectAllText().Input("Some message")
}

The wrapper types would contain the contain the *testing.T and the *rod.Browser or rod.Page and delegate calls to the non-Must methods. If an error was returned they would call t.Fatal(err).

---

It seems that it would be fairly straightforward to build though a bit laborious given how many methods are on Page and Element. So I before I build anything I wanted to ask if this seems like a good or bad idea, if it has already been done, or if there is a better approach.

[ysmood]

Default timeouts per action.

Yes, you can. The API is utils.Sleeper, such as creating a custom sleeper that sleeps no more than 10 seconds.

package main

import (
	"context"
	"fmt"
	"time"

	"github.com/go-rod/rod"
	"github.com/go-rod/rod/lib/utils"
)

func main() {
	page := rod.New().MustConnect().MustPage("http://example.com").Sleeper(mySleeper)

	page.MustElement("a")
	page.MustElement("a")
}

func mySleeper() utils.Sleeper {
	total := time.After(10 * time.Second)

	return func(ctx context.Context) error {
		select {
		case <-time.After(300 * time.Millisecond): // for each retry
			return nil
		case <-ctx.Done():
			return ctx.Err()
		case <-total:
			return fmt.Errorf("timeout after 10s")
		}
	}
}

[ysmood]

The wrapper types would contain the contain the *testing.T and the *rod.Browser or rod.Page and delegate calls to the non-Must methods. If an error was returned they would call t.Fatal(err).

If you want to create a test framework based on rod, please check https://github.com/ysmood/got, rod also uses it to do testing.

I think something like this is enough for you:

package main_test

import (
	"runtime"
	"testing"

	"github.com/go-rod/rod"
)

func TestLab(t *testing.T) {
	b := rod.New().MustConnect().WithPanic(func(v interface{}) {
		_, file, line, _ := runtime.Caller(3)
		t.Logf("%v\n    at %s:%d", v, file, line)
		t.FailNow()
	})

	page := b.MustPage("http://example.com")
	page.MustEval("a")
}

[jackc]

Oh nice! Those are both big helps. Thanks!