add custom locator (#151)

Author: KazuCocoa

CHANGELOG.md

@@ -3,6 +3,12 @@ All notable changes to this project will be documented in this file.
 
 ## [Unreleased]
 ### Enhancements
+- Add custom locator in the future work
+    - https://github.com/appium/appium-base-driver/pull/268/
+    ```
+    @driver.find_element :custom, "f:foo"
+
+    ```
 
 ### Bug fixes
 

lib/appium_lib_core/common/base/search_context.rb

@@ -7,6 +7,7 @@ module SearchContext
         FINDERS = ::Selenium::WebDriver::SearchContext::FINDERS.merge(
           accessibility_id:     'accessibility id',
           image:                '-image',
+          custom:               '-custom',
           # Android
           uiautomator:          '-android uiautomator', # Unavailable in Espresso
           viewtag:              '-android viewtag',     # Available in Espresso

test/unit/driver_test.rb

@@ -83,7 +83,7 @@ def test_default_timeout_for_http_client
 
     # https://www.w3.org/TR/webdriver1/
     def test_search_context_in_element_class
-      assert_equal 19, ::Selenium::WebDriver::Element::FINDERS.length
+      assert_equal 20, ::Selenium::WebDriver::Element::FINDERS.length
       assert_equal({ class: 'class name',
                      class_name: 'class name',
                      css: 'css selector',                    # Defined in W3C spec
@@ -96,8 +96,10 @@ def test_search_context_in_element_class
                      xpath: 'xpath',                         # Defined in W3C spec
                      accessibility_id: 'accessibility id',
                      image: '-image',
+                     custom: '-custom',
                      uiautomator: '-android uiautomator',
-                     viewtag: '-android viewtag', uiautomation: '-ios uiautomation',
+                     viewtag: '-android viewtag',
+                     uiautomation: '-ios uiautomation',
                      predicate: '-ios predicate string',
                      class_chain: '-ios class chain',
                      windows_uiautomation: '-windows uiautomation',