[js] Instead of always writing to a file in the current working directory,

which may not be writable, add a parameter to the phantomjs.Driver
constructor to configure the path to the desired log file.

Still todo: add an Options class so phantomjs configuration is
consistent with the other drivers.

Fixes #1244

Author: jleyba

javascript/node/selenium-webdriver/CHANGES.md

@@ -23,6 +23,9 @@
    module to break a circular dependency.
 * FIXED: `io.findInPath()` will no longer match against directories that have
    the same basename as the target file.
+* FIXED: `phantomjs.Driver` now takes a third argument that defines the path to
+   a log file to use for the phantomjs executable's output. This may be quickly
+   set at runtime with the `SELENIUM_PHANTOMJS_LOG` environment variable.
 
 ### Changes for W3C WebDriver Spec Compliance
 

javascript/node/selenium-webdriver/phantomjs.js

@@ -56,14 +56,6 @@ const BINARY_PATH_CAPABILITY = 'phantomjs.binary.path';
 const CLI_ARGS_CAPABILITY = 'phantomjs.cli.args';
 
 
-/**
- * Default log file to use if one is not specified through CLI args.
- * @type {string}
- * @const
- */
-const DEFAULT_LOG_FILE = 'phantomjsdriver.log';
-
-
 /**
  * Custom command names supported by PhantomJS.
  * @enum {string}
@@ -136,11 +128,16 @@ class Driver extends webdriver.WebDriver {
    *     capabilities.
    * @param {promise.ControlFlow=} opt_flow The control flow to use,
    *     or {@code null} to use the currently active flow.
+   * @param {string=} opt_logFile Path to the log file for the phantomjs
+   *     executable's output. For convenience, this may be set at runtime with
+   *     the `SELENIUM_PHANTOMJS_LOG` environment variable.
    */
-  constructor(opt_capabilities, opt_flow) {
+  constructor(opt_capabilities, opt_flow, opt_logFile) {
+    // TODO: add an Options class for consistency with the other driver types.
+
     var caps = opt_capabilities || capabilities.Capabilities.phantomjs();
     var exe = findExecutable(caps.get(BINARY_PATH_CAPABILITY));
-    var args = ['--webdriver-logfile=' + DEFAULT_LOG_FILE];
+    var args = [];
 
     var logPrefs = caps.get(capabilities.Capability.LOGGING_PREFS);
     if (logPrefs instanceof logging.Preferences) {
@@ -155,6 +152,11 @@ class Driver extends webdriver.WebDriver {
       }
     }
 
+    opt_logFile = process.env['SELENIUM_PHANTOMJS_LOG'] || opt_logFile;
+    if (typeof opt_logFile === 'string') {
+      args.push('--webdriver-logfile=' + opt_logFile);
+    }
+
     var proxy = caps.get(capabilities.Capability.PROXY);
     if (proxy) {
       switch (proxy.proxyType) {