Implement 'uninstall' command

Fixes #10

Makefile

@@ -9,7 +9,7 @@ ifndef TEST_RUNNER
 	# options are: nose, pytest
 	TEST_RUNNER := pytest
 endif
-UNIT_TEST_COVERAGE := 82
+UNIT_TEST_COVERAGE := 80
 INTEGRATION_TEST_COVERAGE := 96
 
 # Project settings

gdm/__init__.py

@@ -15,6 +15,6 @@
     exit("Python {}.{}+ is required.".format(*PYTHON_VERSION))
 
 try:
-    from .commands import install
+    from .commands import install, uninstall
 except ImportError:  # pragma: no cover (manual test)
     pass

gdm/cli.py

@@ -29,23 +29,31 @@ def main(args=None, function=None):
     shared = {'formatter_class': common.WideHelpFormatter,
               'parents': [project, debug]}
 
-    # Build main parser
+    # Main parser
     parser = argparse.ArgumentParser(prog=CLI, description=DESCRIPTION,
                                      **shared)
 
     subs = parser.add_subparsers(help="", dest='command', metavar="<command>")
 
-    # Build switch parser
-    info = "install the specified versions of all dependencies"
+    # Install parser
+    info = "get the specified versions of all dependencies"
     subs.add_parser('install', description=info.capitalize() + '.',
                     help=info, **shared)
 
+    # Uninstall parser
+    info = "remove all installed dependencies"
+    subs.add_parser('uninstall', description=info.capitalize() + '.',
+                    help=info, **shared)
+
     # Parse arguments
     args = parser.parse_args(args=args)
     kwargs = {}
     if args.command == 'install':
         function = commands.install
         kwargs['root'] = args.root
+    elif args.command == 'uninstall':
+        function = commands.uninstall
+        kwargs['root'] = args.root
     if function is None:
         parser.print_help()
         sys.exit(1)

gdm/commands.py

@@ -1,9 +1,10 @@
 """Functions to manage the installation of dependencies."""
 
 import os
+import shutil
 
 from . import common
-from . import config
+from .config import load, install_deps
 
 log = common.logger(__name__)
 
@@ -13,7 +14,7 @@ def install(root=None):
     root = _find_root(root)
 
     log.info("installing dependencies...")
-    count = config.install_deps(root)
+    count = install_deps(root)
     if count == 1:
         log.info("installed 1 dependency")
     elif count > 1:
@@ -24,6 +25,23 @@ def install(root=None):
     return count
 
 
+def uninstall(root=None):
+    """Uninstall dependencies for a project."""
+    root = _find_root(root)
+
+    log.info("uninstalling dependencies...")
+    config = load(root)
+    if config:
+        if os.path.exists(config.location):
+            log.debug("deleting '%s'...", config.location)
+            shutil.rmtree(config.location)
+        log.info("dependencies uninstalled")
+        return True
+    else:
+        log.warn("no dependencies to uninstall")
+        return False
+
+
 def _find_root(root, cwd=None):
     if cwd is None:
         cwd = os.getcwd()

gdm/config.py

@@ -123,12 +123,22 @@ def install_deps(self):
         return count
 
 
-def install_deps(root, indent=0):
-    """Install the dependences listed in the project's configuration file."""
+def load(root):
+    """Load the configuration for the current project."""
+    config = None
     for filename in os.listdir(root):
         if filename.lower() in Config.FILENAMES:
             config = Config(root, filename)
             log.debug("loaded config: %s", config.path)
-            config.indent = indent
-            return config.install_deps()
-    return 0
+            break
+    return config
+
+
+def install_deps(root, indent=0):
+    """Install the dependences listed in the project's configuration file."""
+    config = load(root)
+    if config:
+        config.indent = indent
+        return config.install_deps()
+    else:
+        return 0

gdm/test/test_all.py

@@ -15,8 +15,7 @@
 def test_install():
     """Verify dependencies can be installed."""
     config = Config(FILES)
-    if os.path.exists(config.location):
-        shutil.rmtree(config.location)
+    shutil.rmtree(config.location, ignore_errors=True)
     assert not os.path.exists(config.location)
 
     # clean install
@@ -27,4 +26,16 @@ def test_install():
     assert 'gdm_1' in os.listdir(config.location)
     assert 'gdm_2' in os.listdir(config.location)
 
-    shutil.rmtree(os.path.join(FILES, 'src'))
+    shutil.rmtree(os.path.join(FILES, 'src'), ignore_errors=True)
+
+
+@pytest.mark.integration
+def test_uninstall():
+    """Verify dependencies can be uninstalled."""
+    config = Config(FILES)
+    assert gdm.install(FILES)
+    assert os.path.isdir(config.location)
+
+    assert gdm.uninstall(FILES)
+
+    assert not os.path.isdir(config.location)

gdm/test/test_cli.py

@@ -64,6 +64,23 @@ def test_install_root(self, mock_install):
         mock_install.assert_called_once_with(root='mock/path/to/root')
 
 
+class TestUninstall:
+
+    """Unit tests for the `uninstall` command."""
+
+    @patch('gdm.commands.uninstall')
+    def test_uninstall(self, mock_uninstall):
+        """Verify the 'uninstall' command can be run."""
+        cli.main(['uninstall'])
+        mock_uninstall.assert_called_once_with(root=None)
+
+    @patch('gdm.commands.uninstall')
+    def test_uninstall_root(self, mock_uninstall):
+        """Verify the project's root can be specified."""
+        cli.main(['uninstall', '--root', 'mock/path/to/root'])
+        mock_uninstall.assert_called_once_with(root='mock/path/to/root')
+
+
 class TestLogging:
 
     """Unit tests for logging."""

gdm/test/test_commands.py

@@ -14,6 +14,7 @@
 class TestFindRoot:
 
     def test_specified(self):
+        os.chdir(PROJECT_PARENT)
         assert FILES == _find_root(FILES)
 
     def test_none(self):

gdm/test/test_config.py

@@ -1,9 +1,11 @@
 """Unit tests for the `config` module."""
 # pylint: disable=R0201
 
+import os
+
 import pytest
 
-from gdm.config import Source, Config, install_deps
+from gdm.config import Source, Config, load, install_deps
 
 from .conftest import FILES
 
@@ -74,6 +76,19 @@ def test_path(self):
         assert "mock/root/gdm.yml" == config.path
 
 
+class TestLoad:
+
+    def test_load(self):
+        """Verify a configuration can be loaded."""
+        config = load(FILES)
+        assert None is not config
+
+    def test_load_missing(self):
+        """Verify None is returned for a missing config."""
+        config = load(os.path.dirname(FILES))
+        assert None is config
+
+
 class TestInstall:
 
     @pytest.mark.integration