Ignore IOError’s in ConfigLoader.update

Fixes #932

powerline/lib/config.py

@@ -109,7 +109,8 @@ class ConfigLoader(MultiRunnedThread):
 
 		:param function condition_function:
 			Function which will be called each ``interval`` seconds. All 
-			exceptions from it will be ignored.
+			exceptions from it will be logged and ignored. IOError exception 
+			will be ignored without logging.
 		:param function function:
 			Function which will be called if condition_function returns 
 			something that is true. Accepts result of condition_function as an 
@@ -179,6 +180,8 @@ class ConfigLoader(MultiRunnedThread):
 				for condition_function, function in list(functions):
 					try:
 						path = condition_function(key)
+					except IOError:
+						pass
 					except Exception as e:
 						self.exception('Error while running condition function for key {0}: {1}', key, str(e))
 					else:

tests/lib/fsconfig.py

@@ -0,0 +1,80 @@
+# vim:fileencoding=utf-8:noet
+from __future__ import unicode_literals, absolute_import, division
+
+import os
+import json
+
+from subprocess import check_call
+from operator import add
+from shutil import rmtree
+
+from powerline import Powerline
+
+
+CONFIG_DIR = os.path.join(os.path.dirname(os.path.dirname(os.path.abspath(__file__))), 'config')
+
+
+class TestPowerline(Powerline):
+	def __init__(self, _paths, *args, **kwargs):
+		super(TestPowerline, self).__init__(*args, **kwargs)
+		self._paths = _paths
+
+	def get_config_paths(self):
+		return self._paths
+
+
+def mkdir_recursive(directory):
+	if os.path.isdir(directory):
+		return
+	mkdir_recursive(os.path.dirname(directory))
+	os.mkdir(directory)
+
+
+class FSTree(object):
+	__slots__ = ('tree', 'p', 'p_kwargs', 'create_p', 'get_config_paths', 'root')
+
+	def __init__(
+		self,
+		tree,
+		p_kwargs={'run_once': True},
+		root=CONFIG_DIR,
+		get_config_paths=lambda p: (p,),
+		create_p=False
+	):
+		self.tree = tree
+		self.root = root
+		self.get_config_paths = get_config_paths
+		self.create_p = create_p
+		self.p = None
+		self.p_kwargs = p_kwargs
+
+	def __enter__(self, *args):
+		os.mkdir(self.root)
+		for k, v in self.tree.items():
+			fname = os.path.join(self.root, k) + '.json'
+			mkdir_recursive(os.path.dirname(fname))
+			with open(fname, 'w') as F:
+				json.dump(v, F)
+		if self.create_p:
+			self.p = TestPowerline(
+				_paths=self.get_config_paths(self.root),
+				ext='test',
+				renderer_module='tests.lib.config_mock',
+				**self.p_kwargs
+			)
+		if os.environ.get('POWERLINE_RUN_LINT_DURING_TESTS'):
+			try:
+				check_call(['scripts/powerline-lint'] + reduce(add, (
+					['-p', d] for d in self.p.get_config_paths()
+				)))
+			except:
+				self.__exit__()
+				raise
+		return self.p and self.p.__enter__(*args)
+
+	def __exit__(self, *args):
+		try:
+			rmtree(self.root)
+		finally:
+			if self.p:
+				self.p.__exit__(*args)

tests/test_lib_config.py

@@ -0,0 +1,51 @@
+# vim:fileencoding=utf-8:noet
+from __future__ import unicode_literals, absolute_import, division
+
+import os
+
+from powerline.lib.config import ConfigLoader
+from tests import TestCase
+from tests.lib.fsconfig import FSTree
+
+
+FILE_ROOT = os.path.join(os.path.dirname(__file__), 'cfglib')
+
+
+class LoadedList(list):
+	def pop_all(self):
+		try:
+			return self[:]
+		finally:
+			self[:] = ()
+
+
+loaded = LoadedList()
+
+
+def on_load(key):
+	loaded.append(key)
+
+
+def check_file(path):
+	if os.path.exists(path):
+		return path
+	else:
+		raise IOError
+
+
+class TestLoaderCondition(TestCase):
+	def test_update_missing(self):
+		loader = ConfigLoader(run_once=True)
+		fpath = os.path.join(FILE_ROOT, 'file.json')
+		self.assertRaises(IOError, loader.load, fpath)
+		loader.register_missing(check_file, on_load, fpath)
+		loader.update()  # This line must not raise IOError
+		with FSTree({'file': {'test': 1}}, root=FILE_ROOT):
+			loader.update()
+			self.assertEqual(loader.load(fpath), {'test': 1})
+			self.assertEqual(loaded.pop_all(), [fpath])
+
+
+if __name__ == '__main__':
+	from tests import main
+	main()