Merge pull request #27 from yunstanford/add_uninstall

Add uninstall

tests/test_packages_full.py

@@ -15,6 +15,24 @@ def main(build):
     print("test")
 """.strip()
 
+URANIUM_PY_UNINSTALL = """
+def main(build):
+
+    build.packages.install("pyyaml")
+    import yaml
+    assert yaml is not None
+    build.packages.uninstall("pyyaml")
+
+    import importlib
+    try:
+        importlib.reload(yaml)
+        exist = True
+    except Exception:
+        exist = False
+
+    assert exist == False
+""".strip()
+
 from uranium.scripts import execute_script
 from .conftest import URANIUM_SOURCE_ROOT
 
@@ -31,6 +49,18 @@ def test_install(tmpdir):
     assert code == 0
 
 
+def test_uninstall(tmpdir):
+    # we need to create a virtualenv
+    tmpdir.join("ubuild.py").write(URANIUM_PY_UNINSTALL)
+    code, out, err = execute_script(
+        "uranium_standalone", "--uranium-dir", URANIUM_SOURCE_ROOT,
+        cwd=tmpdir.strpath
+    )
+    print("stdout:\n" + str(out))
+    print("stderr:\n" + str(err))
+    assert code == 0
+
+
 def test_package_cache(tmpdir):
     """ don't event attempt to call pip, if a package already exists. """
     tmpdir.join("ubuild.py").write(URANIUM_PY)

uranium/packages/__init__.py

@@ -1,6 +1,6 @@
 from ..lib.asserts import get_assert_function
 from ..exceptions import PackageException
-from .install_command import install
+from .install_command import install, uninstall
 from .versions import Versions
 
 p_assert = get_assert_function(PackageException)
@@ -88,6 +88,16 @@ def install(self, name, version=None, develop=False, upgrade=False, install_opti
                 if req.installed_version:
                     self.versions[req.name] = ("==" + req.installed_version)
 
+    def uninstall(self, package_name):
+        """
+        uninstall is used when uninstalling a python package from a environment.
+        """
+        p_assert(
+            self._is_package_already_installed(package_name, None),
+            "package {package} doesn't exist".format(package=package_name)
+        )
+        uninstall(package_name)
+
     @staticmethod
     def _is_package_already_installed(name, version):
         import pkg_resources

uranium/packages/install_command.py

@@ -1,4 +1,4 @@
-from pip.commands import InstallCommand
+from pip.commands import InstallCommand, UninstallCommand
 from pip.req.req_file import process_line
 from ..lib.compat import urlparse
 
@@ -60,6 +60,16 @@ def install(package_name, constraint_dict=None, **kwargs):
     return command.run(options, args)
 
 
+def uninstall(package_name, **kwargs):
+    """
+    a convenience function to uninstall a package.
+    """
+    command = UninstallCommand()
+    args = ["--yes", package_name]
+    options, args = command.parse_args(args)
+    return command.run(options, args)
+
+
 def _get_netloc(url):
     parsed_url = urlparse(url)
     return parsed_url.netloc