fix(direct): Use config's geckoDriver when specified (#4554)

* fix(direct): Use config's geckoDriver when specified

This change makes the `firefox` capability more closely match `chrome`'s. The `firefox` capability was not looking for `config_.geckoDriver` like `chrome` was.

lib/driverProviders/direct.ts

@@ -91,15 +91,26 @@ export class Direct extends DriverProvider {
  break;
  case 'firefox':
  let geckoDriverFile: string;
- try {
- let updateJson = path.resolve(SeleniumConfig.getSeleniumDir(), 'update-config.json');
- let updateConfig = JSON.parse(fs.readFileSync(updateJson).toString());
- geckoDriverFile = updateConfig.gecko.last;
- } catch (e) {
+ if (this.config_.geckoDriver) {
+ geckoDriverFile = this.config_.geckoDriver;
+ } else {
+ try {
+ let updateJson = path.resolve(SeleniumConfig.getSeleniumDir(), 'update-config.json');
+ let updateConfig = JSON.parse(fs.readFileSync(updateJson).toString());
+ geckoDriverFile = updateConfig.gecko.last;
+ } catch (e) {
+ throw new BrowserError(
+ logger,
+ 'Could not find update-config.json. ' +
+ 'Run \'webdriver-manager update\' to download binaries.');
+ }
+ }
+
+ if (!fs.existsSync(geckoDriverFile)) {
  throw new BrowserError(
  logger,
- 'Could not find update-config.json. ' +
- 'Run \'webdriver-manager update\' to download binaries.');
+ 'Could not find geckodriver at ' + geckoDriverFile +
+ '. Run \'webdriver-manager update\' to download binaries.');
  }
 
  // TODO (mgiambalvo): Turn this into an import when the selenium typings are updated.