Add library argument and keyword to set sleep between wait until loop (#313)

* Make sleep between wait loop configurable via keyword

* add get sleep_between_wait keyword

* rename keyword

* add sleep_between_wait_loop argument in library import

Author: idxn

AppiumLibrary/__init__.py

@@ -79,7 +79,7 @@ class AppiumLibrary(
     ROBOT_LIBRARY_SCOPE = 'GLOBAL'
     ROBOT_LIBRARY_VERSION = VERSION
 
-    def __init__(self, timeout=5, run_on_failure='Capture Page Screenshot'):
+    def __init__(self, timeout=5, run_on_failure='Capture Page Screenshot', sleep_between_wait_loop=0.2):
         """AppiumLibrary can be imported with optional arguments.
 
         ``timeout`` is the default timeout used to wait for all waiting actions.
@@ -92,12 +92,16 @@ def __init__(self, timeout=5, run_on_failure='Capture Page Screenshot'):
         Using the value `No Operation` will disable this feature altogether. See
         `Register Keyword To Run On Failure` keyword for more information about this
         functionality.
+        
+        ``sleep_between_wait_loop`` is the default sleep used to wait between loop in all wait until keywords
 
         Examples:
         | Library | AppiumLibrary | 10 | # Sets default timeout to 10 seconds                                                                             |
         | Library | AppiumLibrary | timeout=10 | run_on_failure=No Operation | # Sets default timeout to 10 seconds and does nothing on failure           |
+        | Library | AppiumLibrary | timeout=10 | sleep_between_wait_loop=0.3 | # Sets default timeout to 10 seconds and sleep 300 ms between wait loop    |
         """
         for base in AppiumLibrary.__bases__:
             base.__init__(self)
         self.set_appium_timeout(timeout)
         self.register_keyword_to_run_on_failure(run_on_failure)
+        self.set_sleep_between_wait_loop(sleep_between_wait_loop)

AppiumLibrary/keywords/_waiting.py

@@ -4,6 +4,10 @@
 
 
 class _WaitingKeywords(KeywordGroup):
+    
+    def __init__(self):
+        self._sleep_between_wait = 0.2
+        
     def wait_until_element_is_visible(self, locator, timeout=None, error=None):
         """Waits until element specified with `locator` is visible.
 
@@ -111,6 +115,22 @@ def check_present():
 
         self._wait_until_no_error(timeout, check_present)
 
+    def set_sleep_between_wait_loop(self, seconds=0.2):
+        """Sets the sleep in seconds used by wait until loop.
+        
+        If you use the remote appium server, the default value is not recommended because 
+        it is another 200ms overhead to the network latency and will slow down your test
+        execution.
+        """
+        old_sleep = self._sleep_between_wait
+        self._sleep_between_wait = robot.utils.timestr_to_secs(seconds)
+        return old_sleep
+    
+    def get_sleep_between_wait_loop(self):
+        """Gets the sleep between wait loop in seconds that is used by wait until keywords.
+        """
+        return robot.utils.secs_to_timestr(self._sleep_between_wait)
+    
     # Private
 
     def _wait_until(self, timeout, error, function, *args):
@@ -131,7 +151,7 @@ def _wait_until_no_error(self, timeout, wait_func, *args):
             if time.time() > maxtime:
                 self.log_source()
                 raise AssertionError(timeout_error)
-            time.sleep(0.2)
+            time.sleep(self._sleep_between_wait)
 
     def _format_timeout(self, timeout):
         timeout = robot.utils.timestr_to_secs(timeout) if timeout is not None else self._timeout_in_secs