rb: Allow to start mutliple IE drivers in parallel

rb/lib/selenium/webdriver/ie/bridge.rb

@@ -34,7 +34,7 @@ class Bridge < Remote::Bridge
         def initialize(opts = {})
           caps           = opts.delete(:desired_capabilities) { Remote::Capabilities.internet_explorer }
           timeout        = opts.delete(:timeout) { DEFAULT_TIMEOUT }
-          port           = opts.delete(:port) { PortProber.above(DEFAULT_PORT) }
+          port           = opts.delete(:port) { DEFAULT_PORT }
           http_client    = opts.delete(:http_client)
           ignore_mode    = opts.delete(:introduce_flakiness_by_ignoring_security_domains)
           native_events  = opts.delete(:native_events) != false

rb/lib/selenium/webdriver/ie/server.rb

@@ -20,18 +20,24 @@
 module Selenium
   module WebDriver
     module IE
+
+      #
+      # @api private
+      #
+
       class Server
 
-        STOP_TIMEOUT = 5
+        STOP_TIMEOUT        = 5
+        SOCKET_LOCK_TIMEOUT = 45
+        MISSING_TEXT        = "Unable to find standalone executable. Please download the IEDriverServer from http://selenium-release.storage.googleapis.com/index.html and place the executable on your PATH."
 
         def self.get(opts = {})
           binary = IE.driver_path || Platform.find_binary("IEDriverServer")
 
           if binary
             new binary, opts
           else
-            raise Error::WebDriverError,
-              "Unable to find standalone executable. Please download the IEDriverServer from http://selenium-release.storage.googleapis.com/index.html and place the executable on your PATH."
+            raise Error::WebDriverError, MISSING_TEXT
           end
         end
 
@@ -52,23 +58,19 @@ def initialize(binary_path, opts = {})
           unless opts.empty?
             raise ArgumentError, "invalid option#{'s' if opts.size != 1}: #{opts.inspect}"
           end
-
         end
 
         def start(port, timeout)
           return @port if running?
 
           @port = port
-
-          @process = ChildProcess.new(@binary_path, *server_args)
-          @process.io.inherit! if $DEBUG
-          @process.start
-
-          unless SocketPoller.new(Platform.localhost, @port, timeout).connected?
-            raise Error::WebDriverError, "unable to connect to IE server within #{timeout} seconds"
+          socket_lock.locked do
+            find_free_port
+            start_process
+            connect_until_stable(timeout)
           end
 
-          Platform.exit_hook { stop }
+          Platform.exit_hook { stop } # make sure we don't leave the server running
 
           @port
         end
@@ -103,6 +105,28 @@ def server_args
           args
         end
 
+        def find_free_port
+          @port = PortProber.above @port
+        end
+
+        def start_process
+          @process = ChildProcess.new(@binary_path, *server_args)
+          @process.io.inherit! if $DEBUG
+          @process.start
+        end
+
+        def connect_until_stable(timeout)
+          socket_poller = SocketPoller.new Platform.localhost, @port, timeout
+
+          unless socket_poller.connected?
+            raise Error::WebDriverError, "unable to connect to IE server within #{timeout} seconds"
+          end
+        end
+
+        def socket_lock
+          @socket_lock ||= SocketLock.new(@port - 1, SOCKET_LOCK_TIMEOUT)
+        end
+
       end # Server
     end # IE
   end # WebDriver

rb/spec/integration/selenium/webdriver/ie/driver_spec.rb

@@ -0,0 +1,32 @@
+# encoding: utf-8
+#
+# Licensed to the Software Freedom Conservancy (SFC) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The SFC licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+require File.expand_path("../../spec_helper", __FILE__)
+
+module Selenium
+  module WebDriver
+    module IE
+
+      describe Driver do
+        it_behaves_like "driver that can be started concurrently", :ie
+      end
+
+    end # IE
+  end # WebDriver
+end # Selenium