Add tests for libuv-based watcher

Four possible results of running tests (first three are errors):

- “The change to inotify/file2 was not detected” on line 84: most common
- “Spurious change detected” at line 82 (uncommon, usually fixed by sleeping
  before running test in do_test_for_change)
- “The change to inotify was not detected” in tree watcher test (e.g. from line
  131) (very rare)
- All OK.

tests/test_watcher.py

@@ -2,6 +2,7 @@
 from __future__ import absolute_import, unicode_literals, print_function, division
 
 from powerline.lib.watcher import create_file_watcher, create_tree_watcher, INotifyError
+from powerline.lib.watcher.uv import UvNotFound
 from powerline import get_fallback_logger
 from powerline.lib.monotonic import monotonic
 
@@ -16,6 +17,14 @@ from tests import TestCase, SkipTest
 INOTIFY_DIR = 'inotify' + os.environ.get('PYTHON', '')
 
 
+def clear_dir(dir):
+	for root, dirs, files in list(os.walk(dir, topdown=False)):
+		for f in files:
+			os.remove(os.path.join(root, f))
+		for d in dirs:
+			os.rmdir(os.path.join(root, d))
+
+
 class TestFilesystemWatchers(TestCase):
 	def do_test_for_change(self, watcher, path):
 		st = monotonic()
@@ -30,78 +39,104 @@ class TestFilesystemWatchers(TestCase):
 			w = create_file_watcher(pl=get_fallback_logger(), watcher_type='inotify')
 		except INotifyError:
 			raise SkipTest('This test is not suitable for a stat based file watcher')
-		f1, f2, f3 = map(lambda x: os.path.join(INOTIFY_DIR, 'file%d' % x), (1, 2, 3))
+		return self.do_test_file_watcher(w)
-		with open(f1, 'wb'):
+
-			with open(f2, 'wb'):
+	def do_test_file_watcher(self, w):
-				with open(f3, 'wb'):
+		try:
+			f1, f2, f3 = map(lambda x: os.path.join(INOTIFY_DIR, 'file%d' % x), (1, 2, 3))
+			with open(f1, 'wb'):
+				with open(f2, 'wb'):
+					with open(f3, 'wb'):
+						pass
+			ne = os.path.join(INOTIFY_DIR, 'notexists')
+			self.assertRaises(OSError, w, ne)
+			self.assertTrue(w(f1))
+			self.assertTrue(w(f2))
+			os.utime(f1, None), os.utime(f2, None)
+			self.do_test_for_change(w, f1)
+			self.do_test_for_change(w, f2)
+			# Repeat once
+			os.utime(f1, None), os.utime(f2, None)
+			self.do_test_for_change(w, f1)
+			self.do_test_for_change(w, f2)
+			# Check that no false changes are reported
+			self.assertFalse(w(f1), 'Spurious change detected')
+			self.assertFalse(w(f2), 'Spurious change detected')
+			# Check that open the file with 'w' triggers a change
+			with open(f1, 'wb'):
+				with open(f2, 'wb'):
 					pass
-		ne = os.path.join(INOTIFY_DIR, 'notexists')
+			self.do_test_for_change(w, f1)
-		self.assertRaises(OSError, w, ne)
+			self.do_test_for_change(w, f2)
-		self.assertTrue(w(f1))
+			# Check that writing to a file with 'a' triggers a change
-		self.assertTrue(w(f2))
+			with open(f1, 'ab') as f:
-		os.utime(f1, None), os.utime(f2, None)
+				f.write(b'1')
-		self.do_test_for_change(w, f1)
+			self.do_test_for_change(w, f1)
-		self.do_test_for_change(w, f2)
+			# Check that deleting a file registers as a change
-		# Repeat once
+			os.unlink(f1)
-		os.utime(f1, None), os.utime(f2, None)
+			self.do_test_for_change(w, f1)
-		self.do_test_for_change(w, f1)
+			# Test that changing the inode of a file does not cause it to stop
-		self.do_test_for_change(w, f2)
+			# being watched
-		# Check that no false changes are reported
+			os.rename(f3, f2)
-		self.assertFalse(w(f1), 'Spurious change detected')
+			self.do_test_for_change(w, f2)
-		self.assertFalse(w(f2), 'Spurious change detected')
+			self.assertFalse(w(f2), 'Spurious change detected')
-		# Check that open the file with 'w' triggers a change
+			os.utime(f2, None)
-		with open(f1, 'wb'):
+			self.do_test_for_change(w, f2)
-			with open(f2, 'wb'):
+		finally:
-				pass
+			clear_dir(INOTIFY_DIR)
-		self.do_test_for_change(w, f1)
+
-		self.do_test_for_change(w, f2)
+	def test_uv_file_watcher(self):
-		# Check that writing to a file with 'a' triggers a change
+		try:
-		with open(f1, 'ab') as f:
+			w = create_file_watcher(pl=get_fallback_logger(), watcher_type='uv')
-			f.write(b'1')
+		except UvNotFound:
-		self.do_test_for_change(w, f1)
+			raise SkipTest('Pyuv is not available')
-		# Check that deleting a file registers as a change
+		return self.do_test_file_watcher(w)
-		os.unlink(f1)
-		self.do_test_for_change(w, f1)
-		# Test that changing the inode of a file does not cause it to stop
-		# being watched
-		os.rename(f3, f2)
-		self.do_test_for_change(w, f2)
-		self.assertFalse(w(f2), 'Spurious change detected')
-		os.utime(f2, None)
-		self.do_test_for_change(w, f2)
 
 	def test_tree_watcher(self):
 		tw = create_tree_watcher(get_fallback_logger())
-		subdir = os.path.join(INOTIFY_DIR, 'subdir')
+		return self.do_test_tree_watcher(tw)
-		os.mkdir(subdir)
+
-		if tw.watch(INOTIFY_DIR).is_dummy:
+	def do_test_tree_watcher(self, tw):
-			raise SkipTest('No tree watcher available')
+		try:
-		self.assertTrue(tw(INOTIFY_DIR))
+			subdir = os.path.join(INOTIFY_DIR, 'subdir')
-		self.assertFalse(tw(INOTIFY_DIR))
+			os.mkdir(subdir)
-		changed = partial(self.do_test_for_change, tw, INOTIFY_DIR)
+			try:
-		open(os.path.join(INOTIFY_DIR, 'tree1'), 'w').close()
+				if tw.watch(INOTIFY_DIR).is_dummy:
-		changed()
+					raise SkipTest('No tree watcher available')
-		open(os.path.join(subdir, 'tree1'), 'w').close()
+			except UvNotFound:
-		changed()
+				raise SkipTest('Pyuv is not available')
-		os.unlink(os.path.join(subdir, 'tree1'))
+			self.assertTrue(tw(INOTIFY_DIR))
-		changed()
+			self.assertFalse(tw(INOTIFY_DIR))
-		os.rmdir(subdir)
+			changed = partial(self.do_test_for_change, tw, INOTIFY_DIR)
-		changed()
+			open(os.path.join(INOTIFY_DIR, 'tree1'), 'w').close()
-		os.mkdir(subdir)
+			changed()
-		changed()
+			open(os.path.join(subdir, 'tree1'), 'w').close()
-		os.rename(subdir, subdir + '1')
+			changed()
-		changed()
+			os.unlink(os.path.join(subdir, 'tree1'))
-		shutil.rmtree(subdir + '1')
+			changed()
-		changed()
+			os.rmdir(subdir)
-		os.mkdir(subdir)
+			changed()
-		f = os.path.join(subdir, 'f')
+			os.mkdir(subdir)
-		open(f, 'w').close()
+			changed()
-		changed()
+			os.rename(subdir, subdir + '1')
-		with open(f, 'a') as s:
+			changed()
-			s.write(' ')
+			shutil.rmtree(subdir + '1')
-		changed()
+			changed()
-		os.rename(f, f + '1')
+			os.mkdir(subdir)
-		changed()
+			f = os.path.join(subdir, 'f')
+			open(f, 'w').close()
+			changed()
+			with open(f, 'a') as s:
+				s.write(' ')
+			changed()
+			os.rename(f, f + '1')
+			changed()
+		finally:
+			clear_dir(INOTIFY_DIR)
+
+	def test_uv_tree_watcher(self):
+		tw = create_tree_watcher(get_fallback_logger(), 'uv')
+		return self.do_test_tree_watcher(tw)
 
 
 old_cwd = None
@@ -116,11 +151,7 @@ def setUpModule():
 
 def tearDownModule():
 	for d in [INOTIFY_DIR]:
-		for root, dirs, files in list(os.walk(d, topdown=False)):
+		clear_dir(d)
-			for file in files:
-				os.remove(os.path.join(root, file))
-			for dir in dirs:
-				os.rmdir(os.path.join(root, dir))
 		os.rmdir(d)
 	os.chdir(old_cwd)