Nightwatch: Add a step by step mode

[jehon]

When debugging a test, it is usefull to see why a test fail. It would be great to launch a test on a browser, and to run each test one by one (ex: press enter to continue).

[CoderK]

It seems a good idea.
I used to use pause command with a long milliseconds and debug code.

[jehon]

Yes so do I, but with very long tests, it is a pain...

[matskiv]

Good idea, +1

[dxrobinson]

+1! It will be great to have this.

[Akash--]

+1 Yes thats really great idea.

[famer]

Yes, it could be, for instance, run with some --confirm option which will make nightwatch asking confirmation for each step.

[johnboxall]

Here is a quick snippet for custom debug command that will drop you into Node's debugger...

exports.command = function debug(callback) {
    return this.perform(function() {
        debugger;
    });
};

[IndraniBiswas]

+1

[villesau]

here is another really quick snippet derived from @johnboxall s snippet to allow stepping by pressing key. Note that this is not tested properly so use at your own risk!

exports.command = function debug(callback) {
    return this.perform(function(client, done) {
        console.log('press to continue');
        var pressed = false;
        process.stdin.setRawMode(true);
        process.stdin.resume();
        process.stdin.on('data', listener);
        pause();

        function listener() {
            process.stdin.removeListener('keypress', listener);
            process.stdin.pause();
            pressed = true
        }

        function pause() {
            client.pause(10, function() {
                if(!pressed) return pause();
                done();
            });
        }
    });
};

[pschroeder89]

@villesau or @johnboxall, where would I add that these snippets and how would I call the methods?

[villesau]

@scoderp see this page: http://nightwatchjs.org/guide#extending
I'm not sure if the api still is 1:1 the same as a year ago.

[cb109]

@scoderp Inside your nightwatch.conf.js add something like:

module.exports = {
    ...
    custom_commands_path: ['test/e2e/custom-commands']

Then save the code above into a file like debug.js in that directory. Then call in your test like:

browser
  .url(devServer)
  .waitForElementVisible('#app')
  .debug()
  .setValue('input#username', 'admin')
  ...

[pschroeder89]

Thanks @cb109, that worked great

[kretschmannj]

Note that this solution doesn't step by step. It only pauses once waiting for a key press. Once a key is pressed, the test continues on without stopping.