Rename command's tests filenames to test_command_*, and install_tools.py to install.py

The goal is to avoid overlaps between commands and scripts names (for
instance the "install" script and the "install" command)

1 files changed, 99 insertions, 0 deletions

diff --git a/distutils2/install.py b/distutils2/install.py
new file mode 100644
index 0000000..8e898bf
--- /dev/null
+++ b/distutils2/install.py
@@ -0,0 +1,99 @@
+import logging
+from distutils2.index import wrapper
+from distutils2.index.errors import ProjectNotFound, ReleaseNotFound
+from distutils2.depgraph import generate_graph
+from distutils2._backport.pkgutil import get_distributions
+
+
+"""Provides the installation script.
+
+The goal of this script is to install a release from the indexes (eg.
+PyPI), including the dependencies of the releases if needed.
+
+It uses the work made in pkgutil and by the index crawlers to browse the
+installed distributions, and rely on the instalation command to install.
+
+Please note that this installation *script* iis different of the installation
+*command*. While the command only install one distribution, the script installs
+all the dependencies from a distribution, in a secure way.
+"""
+
+
+class InstallationException(Exception):
+    pass
+
+
+def _update_infos(infos, new_infos):
+    """extends the lists contained in the `info` dict with those contained
+    in the `new_info` one
+    """
+    for key, value in infos.items():
+        if key in new_infos:
+            infos[key].extend(new_infos[key])
+
+
+def get_infos(requirements, index=None, installed=None,
+                     prefer_final=True):
+    """Return the informations on what's going to be installed and upgraded.
+
+    :param requirements: is a *string* containing the requirements for this
+                         project (for instance "FooBar 1.1" or "BarBaz (<1.2)")
+    :param index: If an index is specified, use this one, otherwise, use
+                  :class index.ClientWrapper: to get project metadatas.
+    :param installed: a list of already installed distributions.
+    :param prefer_final: when picking up the releases, prefer a "final" one
+                         over a beta/alpha/etc one.
+
+    The results are returned in a dict, containing all the operations
+    needed to install the given requirements::
+
+        >>> get_install_info("FooBar (<=1.2)")
+        {'install': [<FooBar 1.1>], 'remove': [], 'conflict': []}
+
+    Conflict contains all the conflicting distributions, if there is a
+    conflict.
+    """
+
+    if not index:
+        index = wrapper.ClientWrapper()
+
+    if not installed:
+        installed = get_distributions()
+
+    # Get all the releases that match the requirements
+    try:
+        releases = index.get_releases(requirements)
+    except (ReleaseNotFound, ProjectNotFound), e:
+        raise InstallationException('Release not found: "%s"' % requirements)
+
+    # Pick up a release, and try to get the dependency tree
+    release = releases.get_last(requirements, prefer_final=prefer_final)
+
+    # Iter since we found something without conflicts
+    metadata = release.fetch_metadata()
+
+    # Get the distributions already_installed on the system
+    # and add the one we want to install
+
+    distributions = installed + [release]
+    depgraph = generate_graph(distributions)
+
+    # Store all the already_installed packages in a list, in case of rollback.
+    infos = {'install': [], 'remove': [], 'conflict': []}
+
+    # Get what the missing deps are
+    for dists in depgraph.missing.values():
+        if dists:
+            logging.info("missing dependencies found, installing them")
+            # we have missing deps
+            for dist in dists:
+                _update_infos(infos,
+                             get_infos(dist, index, installed))
+
+    # Fill in the infos
+    existing = [d for d in installed if d.name == release.name]
+    if existing:
+        infos['remove'].append(existing[0])
+        infos['conflict'].extend(depgraph.reverse_list[existing[0]])
+    infos['install'].append(release)
+    return infos