From b71b0f710f441cbfa2cb792320c1ecebafba7484 Mon Sep 17 00:00:00 2001
From: Artem Iglikov <artikz@google.com>
Date: Sun, 21 May 2017 18:24:42 +0100
Subject: [PATCH] Make start timeout work properly.

self.alive is an RPC call, which can take a long time (e.g. 45s) if there are problems with communicating to server.
Previously the loop was being executed exactly timeout * 10 times befor timing out, resulting in 450s timeout instead of the requested value.
Now it is executed only until current timestamp is larger or equal the pre-calculated expiration time.
---
 test/test_server.py     | 27 +++++++++++++++++++++++++--
 uiautomator/__init__.py | 11 +++++++----
 2 files changed, 32 insertions(+), 6 deletions(-)

diff --git a/test/test_server.py b/test/test_server.py
index e5e7169..0cd6d6e 100644
--- a/test/test_server.py
+++ b/test/test_server.py
@@ -59,9 +59,32 @@ def test_start_error(self):
         server.ping = MagicMock()
         server.ping.return_value = None
         server.adb = MagicMock()
-        with patch("time.sleep"):
+        with patch("time.sleep") as time_sleep_mock, patch("time.time") as time_time_mock:
+            self._current_time = 0
+            time_sleep_mock.side_effect = self._time_sleep
+            time_time_mock.side_effect = lambda: self._current_time
             with self.assertRaises(IOError):
-                server.start()
+                server.start(timeout=1)
+
+    def _time_sleep(self, timeout):
+        self._current_time += timeout
+
+    # Tests that start() timeout works correctly even in case communication
+    # with device takes too long.
+    def test_start_timeout_works_properly(self):
+        server = AutomatorServer()
+        server.push = MagicMock()
+        server.push.return_value = ["bundle.jar", "uiautomator-stub.jar"]
+        server.ping = MagicMock()
+        server.ping.side_effect = lambda: self._time_sleep(100)
+        server.adb = MagicMock()
+        with patch("time.sleep") as time_sleep_mock, patch("time.time") as time_time_mock:
+            self._current_time = 0
+            time_sleep_mock.side_effect = self._time_sleep
+            time_time_mock.side_effect = lambda: self._current_time
+            with self.assertRaises(IOError):
+                server.start(timeout=1)
+            self.assertGreater(100.2, self._current_time)
 
     def test_auto_start(self):
         try:
diff --git a/uiautomator/__init__.py b/uiautomator/__init__.py
index 677b0b7..85f1e49 100644
--- a/uiautomator/__init__.py
+++ b/uiautomator/__init__.py
@@ -474,10 +474,13 @@ def start(self, timeout=5):
         self.uiautomator_process = self.adb.cmd(*cmd)
         self.adb.forward(self.local_port, self.device_port)
 
-        while not self.alive and timeout > 0:
-            time.sleep(0.1)
-            timeout -= 0.1
-        if not self.alive:
+        step_secs = 0.1
+        expiration_time = time.time() + timeout
+        while time.time() < expiration_time:
+            if self.alive:
+                break
+            time.sleep(step_secs)
+        else:
             raise IOError("RPC server not started!")
 
     def ping(self):