[js] Allow SafariDriver to use Safari Technology Preview

[mojwang]

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[mojwang]

@jleyba do you mind taking a look at this? thx in advance...

[jleyba]

boolean, not Boolean

[mojwang]

Updated the PR with code review feedback

[jleyba]

This will always be false. You don't set the capability on the top-level capabilities object.

[mojwang]

As requested, the capability is not set on the top-level capabilities objects.

[jleyba]

I meant you need to properly handle extracting options from the capabilities object.
For consistency with Java, you should end up with something alone the lines of

// Some details omitted for brevity

class Options {
  setTechnologyPreview(preview) {
    this.options_['technologyPreview'] = !!preview;
    return this;
  }
}

function useTechnologyPreview(obj) {
    if (obj instanceof Options) {
      return !!obj.options_['technologyPreview']
    }

    if (obj && typeof obj === 'object') {
      return !!obj['technologyPreview'];
    }

    return false;
}


class Driver extends webdriver.WebDriver {
  static createSession(opt_config, opt_flow) {
    let caps, exe;

    if (opt_config instanceof Options) {
      caps = opt_config.toCapabilities();

    } else {
      caps = opt_config || Capabilities.safari();
    }

    if (useTechnologyPreview(caps.get(OPTIONS_CAPABILITY_KEY))) {
      exe = SAFARIDRIVER_TECHNOLOGY_PREVIEW_EXE;
    }
    // ...
  }
}

[mojwang]

@jleyba, ah gotcha! Pushing up an update in a few minutes...

[mojwang]

@jleyba, does everything look okay or is there any more feedback in case I missed something?

[jleyba]

One more nit

[jleyba]

options_ may be null. Need:

!!(o.options_ && o.options_[TECHNOLOGY_PREVIEW_OPTIONS_KEY]);

[mojwang]

@jleyba null-check included