Adding upstream version 86.0.1.upstream/86.0.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 178 insertions, 0 deletions

diff --git a/testing/marionette/client/marionette_driver/wait.py b/testing/marionette/client/marionette_driver/wait.py
new file mode 100644
index 0000000000..caa9cb1f86
--- /dev/null
+++ b/testing/marionette/client/marionette_driver/wait.py
@@ -0,0 +1,178 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+from __future__ import absolute_import
+
+import collections
+import sys
+import time
+
+from . import errors
+
+
+DEFAULT_TIMEOUT = 5
+DEFAULT_INTERVAL = 0.1
+
+
+class Wait(object):
+
+    """An explicit conditional utility class for waiting until a condition
+    evaluates to true or not null.
+
+    This will repeatedly evaluate a condition in anticipation for a
+    truthy return value, or its timeout to expire, or its waiting
+    predicate to become true.
+
+    A `Wait` instance defines the maximum amount of time to wait for a
+    condition, as well as the frequency with which to check the
+    condition.  Furthermore, the user may configure the wait to ignore
+    specific types of exceptions whilst waiting, such as
+    `errors.NoSuchElementException` when searching for an element on
+    the page.
+
+    """
+
+    def __init__(
+        self,
+        marionette,
+        timeout=None,
+        interval=None,
+        ignored_exceptions=None,
+        clock=None,
+    ):
+        """Configure the Wait instance to have a custom timeout, interval, and
+        list of ignored exceptions.  Optionally a different time
+        implementation than the one provided by the standard library
+        (time) can also be provided.
+
+        Sample usage::
+
+            # Wait 30 seconds for window to open, checking for its presence once
+            # every 5 seconds.
+            wait = Wait(marionette, timeout=30, interval=5,
+                        ignored_exceptions=errors.NoSuchWindowException)
+            window = wait.until(lambda m: m.switch_to_window(42))
+
+        :param marionette: The input value to be provided to
+            conditions, usually a Marionette instance.
+
+        :param timeout: How long to wait for the evaluated condition
+            to become true.  The default timeout is
+            `wait.DEFAULT_TIMEOUT`.
+
+        :param interval: How often the condition should be evaluated.
+            In reality the interval may be greater as the cost of
+            evaluating the condition function. If that is not the case the
+            interval for the next condition function call is shortend to keep
+            the original interval sequence as best as possible.
+            The default polling interval is `wait.DEFAULT_INTERVAL`.
+
+        :param ignored_exceptions: Ignore specific types of exceptions
+            whilst waiting for the condition.  Any exceptions not
+            whitelisted will be allowed to propagate, terminating the
+            wait.
+
+        :param clock: Allows overriding the use of the runtime's
+            default time library.  See `wait.SystemClock` for
+            implementation details.
+
+        """
+
+        self.marionette = marionette
+        self.timeout = timeout if timeout is not None else DEFAULT_TIMEOUT
+        self.interval = interval if interval is not None else DEFAULT_INTERVAL
+        self.clock = clock or SystemClock()
+        self.end = self.clock.now + self.timeout
+
+        exceptions = []
+        if ignored_exceptions is not None:
+            if isinstance(ignored_exceptions, collections.Iterable):
+                exceptions.extend(iter(ignored_exceptions))
+            else:
+                exceptions.append(ignored_exceptions)
+        self.exceptions = tuple(set(exceptions))
+
+    def until(self, condition, is_true=None, message=""):
+        """Repeatedly runs condition until its return value evaluates to true,
+        or its timeout expires or the predicate evaluates to true.
+
+        This will poll at the given interval until the given timeout
+        is reached, or the predicate or conditions returns true.  A
+        condition that returns null or does not evaluate to true will
+        fully elapse its timeout before raising an
+        `errors.TimeoutException`.
+
+        If an exception is raised in the condition function and it's
+        not ignored, this function will raise immediately.  If the
+        exception is ignored, it will continue polling for the
+        condition until it returns successfully or a
+        `TimeoutException` is raised.
+
+        :param condition: A callable function whose return value will
+            be returned by this function if it evaluates to true.
+
+        :param is_true: An optional predicate that will terminate and
+            return when it evaluates to False.  It should be a
+            function that will be passed clock and an end time.  The
+            default predicate will terminate a wait when the clock
+            elapses the timeout.
+
+        :param message: An optional message to include in the
+            exception's message if this function times out.
+
+        """
+
+        rv = None
+        last_exc = None
+        until = is_true or until_pred
+        start = self.clock.now
+
+        while not until(self.clock, self.end):
+            try:
+                next = self.clock.now + self.interval
+                rv = condition(self.marionette)
+            except (KeyboardInterrupt, SystemExit):
+                raise
+            except self.exceptions:
+                last_exc = sys.exc_info()
+
+            # Re-adjust the interval depending on how long the callback
+            # took to evaluate the condition
+            interval_new = max(next - self.clock.now, 0)
+
+            if not rv:
+                self.clock.sleep(interval_new)
+                continue
+
+            if rv is not None:
+                return rv
+
+            self.clock.sleep(interval_new)
+
+        if message:
+            message = " with message: {}".format(message)
+
+        raise errors.TimeoutException(
+            # pylint: disable=W1633
+            "Timed out after {0:.1f} seconds{1}".format(
+                float(round((self.clock.now - start), 1)), message if message else ""
+            ),
+            cause=last_exc,
+        )
+
+
+def until_pred(clock, end):
+    return clock.now >= end
+
+
+class SystemClock(object):
+    def __init__(self):
+        self._time = time
+
+    def sleep(self, duration):
+        self._time.sleep(duration)
+
+    @property
+    def now(self):
+        return self._time.time()