Added adb_interface.WaitForProcess and WaitForProcessEnd.

Relies mostly on common code factored out of WaitForDevicePm and
WaitForDeviceInstrumentation.

testrunner/adb_interface.py

@@ -302,19 +302,10 @@ class AdbInterface:
     self.SendCommand("wait-for-device")
     # Now the device is there, but may not be running.
     # Query the package manager with a basic command
-    pm_found = False
-    attempts = 0
-    wait_period = 5
-    while not pm_found and (attempts*wait_period) < wait_time:
-      # assume the 'adb shell pm path android' command will always
-      # return 'package: something' in the success case
-      output = self.SendShellCommand("pm path android", retry_count=1)
-      if "package:" in output:
-        pm_found = True
-      else:
-        time.sleep(wait_period)
-        attempts += 1
-    if not pm_found:
+    try:
+      self._WaitForShellCommandContents("pm path android", "package:",
+                                        wait_time)
+    except errors.WaitForResponseTimedOutError:
       raise errors.WaitForResponseTimedOutError(
           "Package manager did not respond after %s seconds" % wait_time)
 
@@ -331,28 +322,88 @@ class AdbInterface:
     instrumentation_path = "%s/%s" % (package_name, runner_name)
     logger.Log("Waiting for instrumentation to be present")
     # Query the package manager
-    inst_found = False
-    attempts = 0
-    wait_period = 5
-    while not inst_found and (attempts*wait_period) < wait_time:
-      # assume the 'adb shell pm list instrumentation'
-      # return 'instrumentation: something' in the success case
     try:
-        output = self.SendShellCommand("pm list instrumentation | grep %s"
-                                       % instrumentation_path, retry_count=1)
-        if "instrumentation:" in output:
-          inst_found = True
-      except errors.AbortError, e:
-        # ignore
-        pass
-      if not inst_found:
-        time.sleep(wait_period)
-        attempts += 1
-    if not inst_found:
+      command = "pm list instrumentation | grep %s" % instrumentation_path
+      self._WaitForShellCommandContents(command, "instrumentation:", wait_time,
+                                        raise_abort=False)
+    except errors.WaitForResponseTimedOutError :
       logger.Log(
           "Could not find instrumentation %s on device. Does the "
           "instrumentation in test's AndroidManifest.xml match definition"
           "in test_defs.xml?" % instrumentation_path)
+      raise
+
+  def WaitForProcess(self, name, wait_time=120):
+    """Wait until a process is running on the device.
+
+    Args:
+      name: the process name as it appears in `ps`
+      wait_time: time in seconds to wait
+
+    Raises:
+      WaitForResponseTimedOutError if wait_time elapses and the process is
+          still not running
+    """
+    logger.Log("Waiting for process %s" % name)
+    self.SendCommand("wait-for-device")
+    self._WaitForShellCommandContents("ps", name, wait_time)
+
+  def WaitForProcessEnd(self, name, wait_time=120):
+    """Wait until a process is no longer running on the device.
+
+    Args:
+      name: the process name as it appears in `ps`
+      wait_time: time in seconds to wait
+
+    Raises:
+      WaitForResponseTimedOutError if wait_time elapses and the process is
+          still running
+    """
+    logger.Log("Waiting for process %s to end" % name)
+    self._WaitForShellCommandContents("ps", name, wait_time, invert=True)
+
+  def _WaitForShellCommandContents(self, command, expected, wait_time,
+                                   raise_abort=True, invert=False):
+    """Wait until the response to a command contains a given output.
+
+    Assumes that a only successful execution of "adb shell <command>" contains
+    the substring expected. Assumes that a device is present.
+
+    Args:
+      command: adb shell command to execute
+      expected: the string that should appear to consider the
+          command successful.
+      wait_time: time in seconds to wait
+      raise_abort: if False, retry when executing the command raises an
+          AbortError, rather than failing.
+      invert: if True, wait until the command output no longer contains the
+          expected contents.
+
+    Raises:
+      WaitForResponseTimedOutError: If wait_time elapses and the command has not
+          returned an output containing expected yet.
+    """
+    # Query the device with the command
+    success = False
+    attempts = 0
+    wait_period = 5
+    while not success and (attempts*wait_period) < wait_time:
+      # assume the command will always contain expected in the success case
+      try:
+        output = self.SendShellCommand(command, retry_count=1)
+        if ((not invert and expected in output)
+            or (invert and expected not in output)):
+          success = True
+      except errors.AbortError, e:
+        if raise_abort:
+          raise
+        # ignore otherwise
+
+      if not success:
+        time.sleep(wait_period)
+        attempts += 1
+
+    if not success:
       raise errors.WaitForResponseTimedOutError()
 
   def Sync(self, retry_count=3):