Merge lp:~elopio/snapcraft/fix1477638-format_strings1 into lp:~snappy-dev/snapcraft/core

[Leo Arias]

Cleanups to prepare for changing the format strings safely.

[lp:~elopio/snapcraft/fix1477638-format_strings1]

111. By Leo Arias on 2015-07-23

Add the missing file.

112. By Leo Arias on 2015-07-24

Moved the plugindir cleanup to the base test case.

113. By Leo Arias on 2015-07-24

Fixed the imports.

Unmerged revisions

=== modified file 'integration-tests/units/jobs.pxu'
--- integration-tests/units/jobs.pxu	2015-07-22 21:05:20 +0000
+++ integration-tests/units/jobs.pxu	2015-07-23 17:20:28 +0000
@@ -3,7 +3,7 @@
 estimated_duration: 0.1
 command:
     set -x
-    OUTPUT=$(${SNAPCRAFT} pull)
+    OUTPUT=$(${SNAPCRAFT} pull 2>&1)
     test $? = 1 || exit 1
     echo $OUTPUT | grep "Could not find snapcraft\.yaml\."
 
@@ -13,7 +13,7 @@
 command:
     set -x
     cp -rT $PLAINBOX_PROVIDER_DATA/assemble .
-    OUTPUT=$(${SNAPCRAFT} assemble)
+    OUTPUT=$(${SNAPCRAFT} assemble 2>&1)
     test $? = 1 || exit 1
     echo $OUTPUT | grep "Missing snappy metadata file"
 
@@ -117,7 +117,7 @@
 command:
     set -x
     cp -rT $PLAINBOX_PROVIDER_DATA/conflicts .
-    OUTPUT=$(${SNAPCRAFT} stage)
+    OUTPUT=$(${SNAPCRAFT} stage 2>&1)
     test $? = 1 || exit 1
     echo $OUTPUT | grep "Error: parts p1 and p2 have the following files in common: bin/test" # squished output by bash
 
@@ -140,7 +140,7 @@
     set -x
     cp -rT $PLAINBOX_PROVIDER_DATA/dependencies .
     sed -i "s/p1:/p1:\n    after: [p3]/" snapcraft.yaml
-    OUTPUT=$(${SNAPCRAFT} pull)
+    OUTPUT=$(${SNAPCRAFT} pull 2>&1)
     test $? = 1 || exit 1
     echo $OUTPUT | grep -i "circular dependency"
 

=== modified file 'snapcraft/__init__.py'
--- snapcraft/__init__.py	2015-07-22 18:59:28 +0000
+++ snapcraft/__init__.py	2015-07-23 17:20:28 +0000
@@ -14,11 +14,16 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
+import logging
 import os
-import snapcraft.common
 import subprocess
 import urllib.parse
 
+import snapcraft.common
+
+
+logger = logging.getLogger(__name__)
+
 
 class BasePlugin:
 
@@ -53,7 +58,7 @@
         if cwd is None:
             cwd = self.builddir
         if True:
-            print(' '.join(cmd))
+            logger.info(' '.join(cmd))
         return snapcraft.common.run(cmd, cwd=cwd, **kwargs)
 
     def isurl(self, url):
@@ -71,7 +76,8 @@
 
     def pull_git(self, source, source_tag=None, source_branch=None):
         if source_tag and source_branch:
-            snapcraft.common.fatal("You can't specify both source-tag and source-branch for a git source (part '%s')." % self.name)
+            logger.error("You can't specify both source-tag and source-branch for a git source (part '%s')." % self.name)
+            snapcraft.common.fatal()
 
         if os.path.exists(os.path.join(self.sourcedir, ".git")):
             refspec = 'HEAD'
@@ -120,11 +126,13 @@
             elif source.startswith("git:"):
                 source_type = 'git'
             elif self.isurl(source):
-                snapcraft.common.fatal("Unrecognized source '%s' for part '%s'." % (source, self.name))
+                logger.error("Unrecognized source '%s' for part '%s'." % (source, self.name))
+                snapcraft.common.fatal()
 
         if source_type == 'bzr':
             if source_branch:
-                snapcraft.common.fatal("You can't specify source-branch for a bzr source (part '%s')." % self.name)
+                logger.error("You can't specify source-branch for a bzr source (part '%s')." % self.name)
+                snapcraft.common.fatal()
             if not self.pull_bzr(source, source_tag=source_tag):
                 return False
             if not self.run(['cp', '-Trfa', self.sourcedir, self.builddir]):
@@ -136,9 +144,11 @@
                 return False
         elif source_type == 'tar':
             if source_branch:
-                snapcraft.common.fatal("You can't specify source-branch for a tar source (part '%s')." % self.name)
+                logger.error("You can't specify source-branch for a tar source (part '%s')." % self.name)
+                snapcraft.common.fatal()
             if source_tag:
-                snapcraft.common.fatal("You can't specify source-tag for a tar source (part '%s')." % self.name)
+                logger.error("You can't specify source-tag for a tar source (part '%s')." % self.name)
+                snapcraft.common.fatal()
             if not self.pull_tarball(source):
                 return False
             if not self.extract_tarball(source):

=== modified file 'snapcraft/cmds.py'
--- snapcraft/cmds.py	2015-07-22 21:05:20 +0000
+++ snapcraft/cmds.py	2015-07-23 17:20:28 +0000
@@ -15,21 +15,27 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 import glob
+import logging
 import os
 import shlex
-import snapcraft.common
-import snapcraft.plugin
-import snapcraft.yaml
 import subprocess
 import sys
 import tempfile
 import time
+
 import yaml
 
+import snapcraft.plugin
+import snapcraft.yaml
+from snapcraft import common
+
+
+logger = logging.getLogger(__name__)
+
 
 def init(args):
     if os.path.exists("snapcraft.yaml"):
-        snapcraft.common.log("snapcraft.yaml already exists!", file=sys.stderr)
+        logger.error('snapcraft.yaml already exists!')
         sys.exit(1)
     yaml = 'parts:\n'
     for part_name in args.part:
@@ -41,23 +47,22 @@
     yaml = yaml.strip()
     with open('snapcraft.yaml', mode='w+') as f:
         f.write(yaml)
-    snapcraft.common.log("Wrote the following as snapcraft.yaml.")
-    print()
-    print(yaml)
+    logger.info('Wrote the following as snapcraft.yaml:\n{}'.format(yaml))
     sys.exit(0)
 
 
 def shell(args):
     config = snapcraft.yaml.Config()
-    snapcraft.common.env = config.stage_env()
+    common.env = config.stage_env()
     userCommand = args.userCommand
     if not userCommand:
         userCommand = ['/usr/bin/env', 'PS1=\[\e[1;32m\]snapcraft:\w\$\[\e[0m\] ', '/bin/bash', '--norc']
-    snapcraft.common.run(userCommand)
+    common.run(userCommand)
 
 
 def wrap_exe(relexepath):
-    exepath = os.path.join(snapcraft.common.snapdir, relexepath)
+    snapdir = common.get_snapdir()
+    exepath = os.path.join(snapdir, relexepath)
     wrappath = exepath + '.wrapper'
 
     try:
@@ -65,13 +70,13 @@
     except Exception:
         pass
 
-    script = "#!/bin/sh\n%s\nexec %s $*" % (snapcraft.common.assemble_env().replace(snapcraft.common.snapdir, "$SNAP_APP_PATH"), '"$SNAP_APP_PATH/%s"' % relexepath)
+    script = "#!/bin/sh\n%s\nexec %s $*" % (common.assemble_env().replace(snapdir, "$SNAP_APP_PATH"), '"$SNAP_APP_PATH/%s"' % relexepath)
     with open(wrappath, 'w+') as f:
         f.write(script)
 
     os.chmod(wrappath, 0o755)
 
-    return os.path.relpath(wrappath, snapcraft.common.snapdir)
+    return os.path.relpath(wrappath, snapdir)
 
 
 def snap(args):
@@ -81,17 +86,17 @@
     config = snapcraft.yaml.Config()
 
     if 'snappy-metadata' in config.data:
-        snapcraft.common.run(
-            ['cp', '-arvT', config.data['snappy-metadata'], snapcraft.common.snapdir + '/meta'])
+        common.run(
+            ['cp', '-arvT', config.data['snappy-metadata'], common.get_snapdir() + '/meta'])
     if not os.path.exists('snap/meta/package.yaml'):
-        snapcraft.common.log("Missing snappy metadata file 'meta/package.yaml'.  Try specifying 'snappy-metadata' in snapcraft.yaml, pointing to a meta directory in your source tree.")
+        logger.error("Missing snappy metadata file 'meta/package.yaml'.  Try specifying 'snappy-metadata' in snapcraft.yaml, pointing to a meta directory in your source tree.")
         sys.exit(1)
 
     # wrap all included commands
     with open("snap/meta/package.yaml", 'r') as f:
         package = yaml.load(f)
 
-    snapcraft.common.env = config.snap_env()
+    common.env = config.snap_env()
 
     def replace_cmd(execparts, cmd):
         newparts = [cmd] + execparts[1:]
@@ -125,7 +130,7 @@
 def assemble(args):
     args.cmd = 'snap'
     snap(args)
-    snapcraft.common.run(['snappy', 'build', snapcraft.common.snapdir])
+    common.run(['snappy', 'build', common.get_snapdir()])
 
 
 def run(args):
@@ -136,7 +141,7 @@
                 os.makedirs(qemudir)
             except FileExistsError:
                 pass
-            snapcraft.common.run(
+            common.run(
                 ['sudo', 'ubuntu-device-flash', 'core', '--developer-mode', '--enable-ssh', '15.04', '-o', qemu_img],
                 cwd=qemudir)
     qemu = subprocess.Popen(
@@ -186,7 +191,7 @@
         for otherPartName in partsFiles:
             common = partFiles & partsFiles[otherPartName]
             if common:
-                snapcraft.common.log("Error: parts %s and %s have the following files in common:\n  %s" % (otherPartName, part.names()[0], '\n  '.join(sorted(common))))
+                logger.error('Error: parts %s and %s have the following files in common:\n  %s' % (otherPartName, part.names()[0], '\n  '.join(sorted(common))))
                 return False
 
         # And add our files to the list
@@ -201,9 +206,9 @@
 
     cmds = [args.cmd]
 
-    if cmds[0] in snapcraft.common.commandOrder:
+    if cmds[0] in common.COMMAND_ORDER:
         forceCommand = cmds[0]
-        cmds = snapcraft.common.commandOrder[0:snapcraft.common.commandOrder.index(cmds[0]) + 1]
+        cmds = common.COMMAND_ORDER[0:common.COMMAND_ORDER.index(cmds[0]) + 1]
 
     config = snapcraft.yaml.Config()
 
@@ -214,7 +219,7 @@
             if subprocess.call(['dpkg-query', '-s', checkpkg], stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL) != 0:
                 newPackages.append(checkpkg)
         if newPackages:
-            print("Installing required packages on the host system: " + ", ".join(newPackages))
+            logger.info('Installing required packages on the host system: ' + ', '.join(newPackages))
             subprocess.call(['sudo', 'apt-get', '-y', 'install'] + newPackages, stdout=subprocess.DEVNULL)
 
     for part in config.all_parts:
@@ -229,8 +234,8 @@
                 if not check_for_collisions(config.all_parts):
                     sys.exit(1)
 
-            snapcraft.common.env = config.build_env_for_part(part)
+            common.env = config.build_env_for_part(part)
             force = forceAll or cmd == forceCommand
             if not getattr(part, cmd)(force=force):
-                snapcraft.common.log("Failed doing %s for %s!" % (cmd, part.names()[0]))
+                logger.error('Failed doing %s for %s!' % (cmd, part.names()[0]))
                 sys.exit(1)

=== modified file 'snapcraft/common.py'
--- snapcraft/common.py	2015-07-14 21:15:07 +0000
+++ snapcraft/common.py	2015-07-23 17:20:28 +0000
@@ -21,6 +21,11 @@
 import sys
 import tempfile
 
+
+COMMAND_ORDER = ["pull", "build", "stage", "snap"]
+_DEFAULT_PLUGINDIR = '/usr/share/snapcraft/plugins'
+_plugindir = _DEFAULT_PLUGINDIR
+
 env = []
 
 
@@ -39,17 +44,22 @@
         return subprocess.call(['/bin/sh', f.name] + cmd, **kwargs) == 0
 
 
-def log(msg, file=None):
-    print('\033[01m' + msg + '\033[0m', file=None)
-
-
 def fatal(msg):
-    log(msg, file=sys.stderr)
     sys.exit(1)
 
 
-commandOrder = ["pull", "build", "stage", "snap"]
-stagedir = os.path.join(os.getcwd(), "stage")
-snapdir = os.path.join(os.getcwd(), "snap")
-
-plugindir = '/usr/share/snapcraft/plugins'
+def get_stagedir():
+    return os.path.join(os.getcwd(), 'stage')
+
+
+def get_snapdir():
+    return os.path.join(os.getcwd(), 'snap')
+
+
+def set_plugindir(plugindir):
+    global _plugindir
+    _plugindir = plugindir
+
+
+def get_plugindir():
+    return _plugindir

=== modified file 'snapcraft/dirs.py'
--- snapcraft/dirs.py	2015-07-20 13:53:07 +0000
+++ snapcraft/dirs.py	2015-07-23 17:20:28 +0000
@@ -19,11 +19,11 @@
 
 def setup_dirs():
     """
-    Ensure that snapcraft.common.plugindir are setup correctly
+    Ensure that snapcraft.common plugindir is setup correctly
     and support running out of a development snapshot
     """
-    import snapcraft.common
+    from snapcraft import common
     topdir = os.path.abspath(os.path.join(__file__, "..", ".."))
     # only change the default if we are running from a checkout
     if os.path.exists(os.path.join(topdir, "setup.py")):
-        snapcraft.common.plugindir = os.path.join(topdir, 'plugins')
+        common.set_plugindir(os.path.join(topdir, 'plugins'))

=== modified file 'snapcraft/main.py'
--- snapcraft/main.py	2015-07-17 17:19:04 +0000
+++ snapcraft/main.py	2015-07-23 17:20:28 +0000
@@ -16,12 +16,20 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 import argparse
+import logging
 import sys
 
 import snapcraft.cmds
 
 
+_COLOR_BOLD = '\033[1m'
+_COLOR_END = '\033[0m'
+
+
 def main():
+    logging.basicConfig(
+        format=_COLOR_BOLD + '%(message)s' + _COLOR_END, level=logging.INFO)
+
     root_parser = argparse.ArgumentParser()
     subparsers = root_parser.add_subparsers(dest='cmd')
 

=== modified file 'snapcraft/plugin.py'
--- snapcraft/plugin.py	2015-07-22 18:59:28 +0000
+++ snapcraft/plugin.py	2015-07-23 17:20:28 +0000
@@ -16,12 +16,18 @@
 
 import glob
 import importlib
+import logging
 import os
-import snapcraft
-import snapcraft.common
 import sys
+
 import yaml
 
+import snapcraft
+from snapcraft import common
+
+
+logger = logging.getLogger(__name__)
+
 
 def is_local_plugin(name):
     return name.startswith("x-")
@@ -31,7 +37,7 @@
     if is_local_plugin(name):
         return os.path.abspath(os.path.join('parts', 'plugins'))
     else:
-        return snapcraft.common.plugindir
+        return common.get_plugindir()
 
 
 class PluginError(Exception):
@@ -69,7 +75,7 @@
     def _load_config(self, name):
         configPath = os.path.join(plugindir(name), name + ".yaml")
         if not os.path.exists(configPath):
-            snapcraft.common.log("Unknown plugin %s" % name, file=sys.stderr)
+            logger.error("Unknown plugin %s" % name)
             raise PluginError()
         with open(configPath, 'r') as fp:
             self.config = yaml.load(fp) or {}
@@ -86,7 +92,7 @@
                 setattr(options, attrname, properties[opt])
             else:
                 if opt_parameters.get('required', False):
-                    snapcraft.common.log("Required field %s missing on part %s" % (opt, name), file=sys.stderr)
+                    logger.error("Required field %s missing on part %s" % (opt, name))
                     raise PluginError()
                 setattr(options, attrname, None)
 
@@ -147,13 +153,13 @@
         return self.part_names
 
     def notify_stage(self, stage, hint=''):
-        snapcraft.common.log(stage + " " + self.part_names[0] + hint)
+        logger.info(stage + " " + self.part_names[0] + hint)
 
     def is_dirty(self, stage):
         try:
             with open(self.statefile, 'r') as f:
                 lastStep = f.read()
-                return snapcraft.common.commandOrder.index(stage) > snapcraft.common.commandOrder.index(lastStep)
+                return common.COMMAND_ORDER.index(stage) > common.COMMAND_ORDER.index(lastStep)
         except Exception:
             return True
 
@@ -197,7 +203,7 @@
             return True
 
         self.notify_stage("Staging")
-        snapcraft.common.run(['cp', '-arT', self.installdir, self.stagedir])
+        common.run(['cp', '-arT', self.installdir, self.stagedir])
         self.mark_done('stage')
         return True
 
@@ -213,9 +219,9 @@
             snapDirs, snap_files = self.collect_snap_files(includes, excludes)
 
             if snapDirs:
-                snapcraft.common.run(['mkdir', '-p'] + list(snapDirs), cwd=self.stagedir)
+                common.run(['mkdir', '-p'] + list(snapDirs), cwd=self.stagedir)
             if snap_files:
-                snapcraft.common.run(['cp', '-a', '--parent'] + list(snap_files) + [self.snapdir], cwd=self.stagedir)
+                common.run(['cp', '-a', '--parent'] + list(snap_files) + [self.snapdir], cwd=self.stagedir)
 
             self.mark_done('snap')
         return True
@@ -274,6 +280,6 @@
 def load_plugin(part_name, plugin_name, properties={}, load_code=True):
     part = PluginHandler(plugin_name, part_name, properties, load_code=load_code)
     if not part.is_valid():
-        snapcraft.common.log("Could not load part %s" % plugin_name, file=sys.stderr)
+        logger.error("Could not load part %s" % plugin_name)
         sys.exit(1)
     return part

=== modified file 'snapcraft/plugins/ant_project.py'
--- snapcraft/plugins/ant_project.py	2015-07-22 18:23:16 +0000
+++ snapcraft/plugins/ant_project.py	2015-07-23 17:20:28 +0000
@@ -15,10 +15,15 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 import glob
+import logging
 import os
+import sys
+
 import snapcraft
 import snapcraft.common
-import sys
+
+
+logger = logging.getLogger(__name__)
 
 
 class AntProjectPlugin(snapcraft.BasePlugin):
@@ -31,7 +36,7 @@
             return False
         files = glob.glob(os.path.join(self.builddir, 'target', '*.jar'))
         if not files:
-            snapcraft.common.log('Could not find any built jar files for part %s' % self.name)
+            logger.error('Could not find any built jar files for part %s' % self.name)
             sys.exit(1)
         jardir = os.path.join(self.installdir, 'jar')
         return self.run(['mkdir', '-p', jardir]) and \

=== modified file 'snapcraft/plugins/copy.py'
--- snapcraft/plugins/copy.py	2015-07-22 14:55:48 +0000
+++ snapcraft/plugins/copy.py	2015-07-23 17:20:28 +0000
@@ -14,11 +14,15 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
+import logging
 import os
 
 import snapcraft
 
 
+logger = logging.getLogger(__name__)
+
+
 class CopyPlugin(snapcraft.BasePlugin):
 
     def build(self):
@@ -26,7 +30,7 @@
         for src in sorted(self.options.files):
             dst = self.options.files[src]
             if not os.path.lexists(src):
-                snapcraft.common.log("WARNING: file '%s' missing" % src)
+                logger.warning("WARNING: file '%s' missing" % src)
                 res = False
                 continue
             dst = os.path.join(self.installdir, dst)

=== modified file 'snapcraft/plugins/ubuntu.py'
--- snapcraft/plugins/ubuntu.py	2015-07-22 18:23:16 +0000
+++ snapcraft/plugins/ubuntu.py	2015-07-23 17:20:28 +0000
@@ -14,12 +14,18 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-import apt
+import logging
 import os
-import snapcraft.common
 import subprocess
 import sys
 
+import apt
+
+import snapcraft.common
+
+
+logger = logging.getLogger(__name__)
+
 
 class UbuntuPlugin(snapcraft.BasePlugin):
 
@@ -32,7 +38,7 @@
         else:
             # User didn't specify a package, use the part name
             if name == 'ubuntu':
-                snapcraft.common.log("Part %s needs either a package option or a name" % name)
+                logger.error('Part %s needs either a package option or a name' % name)
                 sys.exit(1)
             self.included_packages.append(name)
 
@@ -83,7 +89,7 @@
         for p in packages:
             if p not in alldeps:
                 exit = True
-                snapcraft.common.log("Package %s not recognized" % p, file=sys.stderr)
+                logger.error('Package %s not recognized' % p, file=sys.stderr)
         if exit:
             sys.exit(1)
 

=== modified file 'snapcraft/tests/__init__.py'
--- snapcraft/tests/__init__.py	2015-07-22 15:03:34 +0000
+++ snapcraft/tests/__init__.py	2015-07-23 17:20:28 +0000
@@ -16,7 +16,6 @@
 
 import fixtures
 
-import snapcraft.dirs
 from snapcraft.tests import fixture_setup
 
 
@@ -24,5 +23,6 @@
 
     def setUp(self):
         super().setUp()
-        snapcraft.dirs.setup_dirs()
-        self.useFixture(fixture_setup.TempCWD())
+        temp_cwd_fixture = fixture_setup.TempCWD()
+        self.useFixture(temp_cwd_fixture)
+        self.path = temp_cwd_fixture.path

=== modified file 'snapcraft/tests/test_cmds.py'
--- snapcraft/tests/test_cmds.py	2015-07-15 09:00:46 +0000
+++ snapcraft/tests/test_cmds.py	2015-07-23 17:20:28 +0000
@@ -14,18 +14,23 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
+import logging
 import os
 import tempfile
 from unittest import mock
 
-from snapcraft.cmds import check_for_collisions
+import fixtures
+
+from snapcraft import cmds
 from snapcraft.tests import TestCase
 
 
 class TestCommands(TestCase):
 
-    @mock.patch('snapcraft.common.log')
-    def test_check_for_collisions(self, logmock):
+    def test_check_for_collisions(self):
+        fake_logger = fixtures.FakeLogger(level=logging.ERROR)
+        self.useFixture(fake_logger)
+
         tmpdirObject = tempfile.TemporaryDirectory()
         self.addCleanup(tmpdirObject.cleanup)
         tmpdir = tmpdirObject.name
@@ -52,8 +57,41 @@
         open(part3.installdir + '/1', mode='w').close()
         open(part3.installdir + '/a/2', mode='w').close()
 
-        self.assertTrue(check_for_collisions([part1, part2]))
-        self.assertFalse(logmock.called)
-
-        self.assertFalse(check_for_collisions([part1, part2, part3]))
-        logmock.assert_called_with("Error: parts part2 and part3 have the following files in common:\n  1\n  a/2")
+        self.assertTrue(cmds.check_for_collisions([part1, part2]))
+        self.assertEqual('', fake_logger.output)
+
+        self.assertFalse(cmds.check_for_collisions([part1, part2, part3]))
+        self.assertEqual(
+            'Error: parts part2 and part3 have the following files in common:\n'
+            '  1\n'
+            '  a/2\n',
+            fake_logger.output)
+
+
+class InitTestCase(TestCase):
+
+    def test_init_with_existing_snapcraft_yaml_must_fail(self):
+        fake_logger = fixtures.FakeLogger(level=logging.ERROR)
+        self.useFixture(fake_logger)
+
+        open('snapcraft.yaml', 'w').close()
+
+        with self.assertRaises(SystemExit) as raised:
+            cmds.init('dummy args')
+        self.assertEqual(raised.exception.code, 1, 'Wrong exit code returned.')
+        self.assertEqual(
+            'snapcraft.yaml already exists!\n', fake_logger.output)
+
+    def test_init_without_parts_must_write_snapcraft_yaml(self):
+        fake_logger = fixtures.FakeLogger(level=logging.INFO)
+        self.useFixture(fake_logger)
+
+        snap_without_parts = type('obj', (object, ), {'part': []})
+        with self.assertRaises(SystemExit) as raised:
+            cmds.init(snap_without_parts)
+
+        self.assertEqual(raised.exception.code, 0, 'Wrong exit code returned.')
+        self.assertEqual(
+            'Wrote the following as snapcraft.yaml:\n'
+            'parts:\n',
+            fake_logger.output)

=== modified file 'snapcraft/tests/test_copy_plugin.py'
--- snapcraft/tests/test_copy_plugin.py	2015-07-22 21:05:20 +0000
+++ snapcraft/tests/test_copy_plugin.py	2015-07-23 17:20:28 +0000
@@ -14,11 +14,11 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
+import logging
 import os.path
-from unittest.mock import (
-    Mock,
-    patch,
-)
+from unittest.mock import Mock
+
+import fixtures
 
 from snapcraft.plugins.copy import CopyPlugin
 from snapcraft.tests import TestCase
@@ -43,12 +43,17 @@
         }
         open("zzz", "w").close()
         c = CopyPlugin("copy", self.mock_options)
-        with patch("snapcraft.common.log") as mock_log:
-            res = c.build()
-            self.assertFalse(res)
-            mock_log.assert_called_with("WARNING: file 'src' missing")
+
+        fake_logger = fixtures.FakeLogger(level=logging.WARNING)
+        self.useFixture(fake_logger)
+
+        res = c.build()
+        self.assertFalse(res)
+        self.assertEqual("WARNING: file 'src' missing\n", fake_logger.output)
 
     def test_copy_plugin_copies(self):
+        self.useFixture(fixtures.FakeLogger())
+
         self.mock_options.files = {
             "src": "dst",
         }
@@ -59,6 +64,8 @@
         self.assertTrue(os.path.exists(os.path.join(self.dst_prefix, "dst")))
 
     def test_copy_plugin_creates_prefixes(self):
+        self.useFixture(fixtures.FakeLogger())
+
         self.mock_options.files = {
             "src": "dir/dst",
         }

=== modified file 'snapcraft/tests/test_plugin.py'
--- snapcraft/tests/test_plugin.py	2015-07-22 21:05:20 +0000
+++ snapcraft/tests/test_plugin.py	2015-07-23 17:20:28 +0000
@@ -14,25 +14,29 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
+import logging
 import os
 import sys
 import tempfile
 
+import fixtures
 from unittest.mock import (
     Mock,
     patch,
 )
 
+import snapcraft.tests.mock_plugin
 from snapcraft.plugin import PluginHandler, PluginError
 from snapcraft.tests import TestCase
 
-import snapcraft.tests.mock_plugin
-
 
 class TestPlugin(TestCase):
 
+    def get_test_plugin(self):
+        return PluginHandler('mock', 'mock-part', {}, load_config=False, load_code=False)
+
     def test_is_dirty(self):
-        p = PluginHandler("mock", "mock-part", {}, load_config=False, load_code=False)
+        p = self.get_test_plugin()
         p.statefile = tempfile.NamedTemporaryFile().name
         self.addCleanup(os.remove, p.statefile)
         p.code = Mock()
@@ -45,7 +49,7 @@
         self.assertFalse(p.code.pull.called)
 
     def test_collect_snap_files(self):
-        p = PluginHandler("mock", "mock-part", {}, load_config=False, load_code=False)
+        p = self.get_test_plugin()
 
         tmpdirObject = tempfile.TemporaryDirectory()
         self.addCleanup(tmpdirObject.cleanup)
@@ -92,6 +96,15 @@
             set(['1', '1/1a', '1/1a/1b', '2', '2/2a']),
             set()))
 
+    def test_notify_stage_must_log_information(self):
+        fake_logger = fixtures.FakeLogger(level=logging.INFO)
+        self.useFixture(fake_logger)
+
+        plugin = self.get_test_plugin()
+        plugin.notify_stage('test stage')
+
+        self.assertEqual('test stage mock-part\n', fake_logger.output)
+
     def test_local_plugins(self):
         """Ensure local plugins are loaded from parts/plugins"""
         def mock_import_modules(module_name):

=== modified file 'snapcraft/tests/test_yaml.py'
--- snapcraft/tests/test_yaml.py	2015-07-17 17:00:18 +0000
+++ snapcraft/tests/test_yaml.py	2015-07-23 17:20:28 +0000
@@ -14,15 +14,18 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
+import logging
 import os
 import tempfile
 import unittest
-from unittest.mock import (
-    patch,
+
+import fixtures
+
+from snapcraft import (
+    common,
+    dirs
 )
-
 from snapcraft.yaml import Config
-
 from snapcraft.tests import TestCase
 
 
@@ -46,16 +49,27 @@
             "package": "fswebcam",
         })
 
-    @patch("snapcraft.common.log")
-    def test_config_raises_on_missing_snapcraft_yaml(self, mock_log):
+    def test_config_raises_on_missing_snapcraft_yaml(self):
+        fake_logger = fixtures.FakeLogger(level=logging.ERROR)
+        self.useFixture(fake_logger)
+
         # no snapcraft.yaml
-        with self.assertRaises(SystemExit):
+        with self.assertRaises(SystemExit) as raised:
             Config()
-        mock_log.assert_called_with("""Could not find snapcraft.yaml.  Are you sure you're in the right directory?
-To start a new project, use 'snapcraft init'""")
-
-    @patch("snapcraft.common.log")
-    def test_config_loop(self, mock_log):
+
+        self.assertEqual(raised.exception.code, 1, 'Wrong exit code returned.')
+        self.assertEqual(
+            "Could not find snapcraft.yaml.  Are you sure you're in the right directory?\n"
+            "To start a new project, use 'snapcraft init'\n",
+            fake_logger.output)
+
+    def test_config_loop(self):
+        self.addCleanup(common.set_plugindir, common.get_plugindir())
+        dirs.setup_dirs()
+
+        fake_logger = fixtures.FakeLogger(level=logging.ERROR)
+        self.useFixture(fake_logger)
+
         self.make_snapcraft_yaml("""parts:
   p1:
     plugin: ubuntu
@@ -64,6 +78,8 @@
     plugin: ubuntu
     after: [p1]
 """)
-        with self.assertRaises(SystemExit):
+        with self.assertRaises(SystemExit) as raised:
             Config()
-        mock_log.assert_called_with("Circular dependency chain!")
+
+        self.assertEqual(raised.exception.code, 1, 'Wrong exit code returned.')
+        self.assertEqual('Circular dependency chain!\n', fake_logger.output)

=== modified file 'snapcraft/yaml.py'
--- snapcraft/yaml.py	2015-07-22 13:57:19 +0000
+++ snapcraft/yaml.py	2015-07-23 17:20:28 +0000
@@ -14,11 +14,17 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-import snapcraft.common
-import snapcraft.plugin
+import logging
 import sys
+
 import yaml
 
+import snapcraft.plugin
+from snapcraft import common
+
+
+logger = logging.getLogger(__name__)
+
 
 class Config:
 
@@ -31,7 +37,7 @@
             with open("snapcraft.yaml", 'r') as fp:
                 self.data = yaml.load(fp)
         except FileNotFoundError:
-            snapcraft.common.log("Could not find snapcraft.yaml.  Are you sure you're in the right directory?\nTo start a new project, use 'snapcraft init'")
+            logger.error("Could not find snapcraft.yaml.  Are you sure you're in the right directory?\nTo start a new project, use 'snapcraft init'")
             sys.exit(1)
         self.build_tools = self.data.get('build-tools', [])
 
@@ -75,7 +81,7 @@
                         foundIt = True
                         break
                 if not foundIt:
-                    snapcraft.common.log("Could not find part name %s" % dep)
+                    logger.error("Could not find part name %s" % dep)
                     sys.exit(1)
 
         # Now sort them (this is super inefficient, but easy-ish to follow)
@@ -92,7 +98,7 @@
                     topPart = part
                     break
             if not topPart:
-                snapcraft.common.log("Circular dependency chain!")
+                logger.error("Circular dependency chain!")
                 sys.exit(1)
             sortedParts = [topPart] + sortedParts
             self.all_parts.remove(topPart)
@@ -132,7 +138,7 @@
         return env
 
     def stage_env(self):
-        root = snapcraft.common.stagedir
+        root = common.get_stagedir()
         env = []
 
         env += self.runtime_env(root)
@@ -143,7 +149,7 @@
         return env
 
     def snap_env(self):
-        root = snapcraft.common.snapdir
+        root = common.get_snapdir()
         env = []
 
         env += self.runtime_env(root)