cli: stage command migrated to docopts

This also introduces recursive lifecycle execution to properly
handle dependencies.

Signed-off-by: Sergio Schvezov <sergio.schvezov@canonical.com>

snapcraft/commands/stage.py

@@ -0,0 +1,39 @@
+# -*- Mode:Python; indent-tabs-mode:nil; tab-width:4 -*-
+#
+# Copyright (C) 2015 Canonical Ltd
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 3 as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+"""
+snapcraft stage
+
+Stage parts.
+
+Usage:
+  stage [options] [PART ...]
+
+Options:
+  -h --help             show this help message and exit.
+
+"""
+
+from docopt import docopt
+
+from snapcraft import lifecycle
+
+
+def main(argv=None):
+    argv = argv if argv else []
+    args = docopt(__doc__, argv=argv)
+
+    lifecycle.execute('stage', args['PART'])

snapcraft/lifecycle.py

@@ -15,6 +15,7 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 import contextlib
+import filecmp
 import glob
 import importlib
 import logging
@@ -48,15 +49,30 @@ def execute(step, part_names=None):
         parts = {p for p in config.all_parts if p.name in part_names}
     else:
         parts = config.all_parts
+        part_names = config.part_names
 
     step_index = common.COMMAND_ORDER.index(step) + 1
     for step in common.COMMAND_ORDER[0:step_index]:
+        if step == 'stage':
+            _check_for_collisions(config.all_parts)
         for part in parts:
+            prereqs = config.part_prereqs(part.name)
+            if prereqs and not prereqs.issubset(part_names):
+                raise RuntimeError(
+                    'Requested {!r} of {!r} but there are prerequisites: '
+                    '{!r}'.format(step, part.name, ' '.join(prereqs)))
+            elif prereqs:
+                # prerequisites need to build all the way to the staging
+                # step to be able to share the common assets that make them
+                # a dependency.
+                execute('stage', prereqs)
             common.env = config.build_env_for_part(part)
             if step == 'pull':
                 part.pull()
             elif step == 'build':
                 part.build()
+            elif step == 'stage':
+                part.stage()
 
 
 class PluginError(Exception):
@@ -420,3 +436,35 @@ def _validate_relative_paths(files):
     for d in files:
         if os.path.isabs(d):
             raise PluginError('path "{}" must be relative'.format(d))
+
+
+def _check_for_collisions(parts):
+    parts_files = {}
+    for part in parts:
+        # Gather our own files up
+        part_files, _ = part.migratable_fileset_for('stage')
+
+        # Scan previous parts for collisions
+        for other_part_name in parts_files:
+            common = part_files & parts_files[other_part_name]['files']
+            conflict_files = []
+            for f in common:
+                this = os.path.join(part.installdir, f)
+                other = os.path.join(
+                    parts_files[other_part_name]['installdir'],
+                    f)
+                if os.path.islink(this) and os.path.islink(other):
+                    continue
+                if not filecmp.cmp(this, other, shallow=False):
+                    conflict_files.append(f)
+
+            if conflict_files:
+                raise EnvironmentError(
+                    'Parts {!r} and {!r} have the following file paths in '
+                    'common which have different contents:\n{}'.format(
+                         other_part_name, part.name,
+                         '\n'.join(sorted(conflict_files))))
+
+        # And add our files to the list
+        parts_files[part.name] = {'files': part_files,
+                                  'installdir': part.installdir}

snapcraft/tests/test_cmds.py

@@ -16,16 +16,13 @@
 
 import logging
 import os
-import tempfile
 
 import fixtures
 
 import snapcraft.yaml
 
 from snapcraft import (
-    cmds,
     common,
-    lifecycle,
     tests
 )
 
@@ -37,49 +34,6 @@ def setUp(self):
         common.set_schemadir(os.path.join(__file__,
                              '..', '..', '..', 'schema'))
 
-    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
-
-        part1 = lifecycle.load_plugin('part1', 'jdk', {'source': '.'})
-        part1.code.installdir = tmpdir + '/install1'
-        os.makedirs(part1.installdir + '/a')
-        open(part1.installdir + '/a/1', mode='w').close()
-
-        part2 = lifecycle.load_plugin('part2', 'jdk', {'source': '.'})
-        part2.code.installdir = tmpdir + '/install2'
-        os.makedirs(part2.installdir + '/a')
-        with open(part2.installdir + '/1', mode='w') as f:
-            f.write('1')
-        open(part2.installdir + '/2', mode='w').close()
-        with open(part2.installdir + '/a/2', mode='w') as f:
-            f.write('a/2')
-
-        part3 = lifecycle.load_plugin('part3', 'jdk', {'source': '.'})
-        part3.code.installdir = tmpdir + '/install3'
-        os.makedirs(part3.installdir + '/a')
-        os.makedirs(part3.installdir + '/b')
-        with open(part3.installdir + '/1', mode='w') as f:
-            f.write('2')
-        with open(part2.installdir + '/2', mode='w') as f:
-            f.write('1')
-        open(part3.installdir + '/a/2', mode='w').close()
-
-        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 file paths in '
-            'common which have different contents:\n'
-            '  1\n'
-            '  a/2\n',
-            fake_logger.output)
-
     def test_load_config_with_invalid_plugin_exits_with_error(self):
         fake_logger = fixtures.FakeLogger(level=logging.ERROR)
         self.useFixture(fake_logger)