New approach to discovery of VCS backends

pip/util.py

@@ -609,3 +609,14 @@ def call_subprocess(cmd, show_stdout=True,
                 % (command_desc, proc.returncode, cwd))
     if stdout is not None:
         return ''.join(all_output)
+
+def setup_project_name(setup_py):
+    try:
+        cmd = [sys.executable, setup_py, '--name']
+        proc = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+    except Exception:
+        e = sys.exc_info()[1]
+        logger.warn(
+            "Error %s while executing command %s" % (e, ' '.join(cmd)))
+    proc.wait()
+    return pkg_resources.safe_name(proc.stdout.read().strip())

pip/vcs/__init__.py

@@ -60,12 +60,11 @@ def unregister(self, cls=None, name=None):
     def get_backend_name(self, dist):
         """
         Return the name of the version control backend if found at given
-        location, e.g. vcs.get_backend_name(dist)
+        pkg_resources.distribution, e.g. vcs.get_backend_name(dist)
         """
         for vc_type in self._registry.values():
-            location = os.path.join(dist.location.split(dist.key)[0], dist.key)
-            path = os.path.join(location, vc_type.dirname)
-            if os.path.exists(path):
+            vc = vc_type()
+            if vc.check_repository(dist):
                 return vc_type.name
         return None
 
@@ -113,6 +112,9 @@ def cmd(self):
         self._cmd = command
         return command
 
+    def check_repository(self, dist):
+        raise NotImplementedError
+
     def get_url_rev(self):
         """
         Returns the correct repository URL and revision by parsing the given

pip/vcs/bazaar.py

@@ -1,9 +1,11 @@
 import os
+import subprocess
 import tempfile
 import re
+import sys
 from pip.backwardcompat import urlparse
 from pip.log import logger
-from pip.util import rmtree, display_path, call_subprocess
+from pip.util import rmtree, display_path, call_subprocess, setup_project_name
 from pip.vcs import vcs, VersionControl
 from pip.download import path_to_url2
 
@@ -25,6 +27,29 @@ def __init__(self, url=None, *args, **kwargs):
             urlparse.uses_fragment.extend(['lp'])
             urlparse.non_hierarchical.extend(['lp'])
 
+    def check_repository(self, dist):
+        status_error = 'bzr: ERROR: Not a branch:'
+        try:
+            cmd = [self.cmd, 'root']
+            proc = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, cwd=dist.location)
+        except Exception:
+            e = sys.exc_info()[1]
+            logger.warn(
+                "Error %s while executing command %s" % (e, ' '.join(cmd)))
+        proc.wait()
+        stderr = proc.stderr.read()
+        stdout = proc.stdout.read()
+        if status_error in stderr:
+            return False
+        root_path = stdout.strip()
+        setup_py = os.path.join(root_path, 'setup.py')
+        if not os.path.isfile(setup_py):
+                return False
+        if setup_project_name(setup_py) != dist.project_name:
+            return False
+        return True
+
+
     def parse_vcs_bundle_file(self, content):
         url = rev = None
         for line in content.splitlines():

pip/vcs/git.py

@@ -1,7 +1,9 @@
 import tempfile
 import re
 import os.path
-from pip.util import call_subprocess
+import sys
+import subprocess
+from pip.util import call_subprocess, setup_project_name
 from pip.util import display_path, rmtree
 from pip.vcs import vcs, VersionControl
 from pip.log import logger
@@ -34,6 +36,28 @@ def __init__(self, url=None, *args, **kwargs):
 
         super(Git, self).__init__(url, *args, **kwargs)
 
+    def check_repository(self, dist):
+        status_error = 'fatal: Not a git repository (or any of the parent directories): .git'
+        try:
+            cmd = [self.cmd, 'rev-parse', '--show-toplevel']
+            proc = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, cwd=dist.location)
+        except Exception:
+            e = sys.exc_info()[1]
+            logger.warn(
+                "Error %s while executing command %s" % (e, ' '.join(cmd)))
+        proc.wait()
+        stderr = proc.stderr.read()
+        stdout = proc.stdout.read()
+        if status_error in stderr:
+            return False
+        root_path = stdout.strip()
+        setup_py = os.path.join(root_path, 'setup.py')
+        if not os.path.isfile(setup_py):
+            return False
+        if setup_project_name(setup_py) != dist.project_name:
+            return False
+        return True
+
     def parse_vcs_bundle_file(self, content):
         url = rev = None
         for line in content.splitlines():

pip/vcs/mercurial.py

@@ -1,8 +1,9 @@
 import os
+import subprocess
 import tempfile
 import re
 import sys
-from pip.util import call_subprocess
+from pip.util import call_subprocess, setup_project_name
 from pip.util import display_path, rmtree
 from pip.log import logger
 from pip.vcs import vcs, VersionControl
@@ -19,6 +20,29 @@ class Mercurial(VersionControl):
     guide = ('# This was a Mercurial repo; to make it a repo again run:\n'
             'hg init\nhg pull %(url)s\nhg update -r %(rev)s\n')
 
+    def check_repository(self, dist):
+        status_error = 'abort: no repository found in'
+        try:
+            cmd = [self.cmd, 'root']
+            proc = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, cwd=dist.location)
+        except Exception:
+            e = sys.exc_info()[1]
+            logger.warn(
+                "Error %s while executing command %s" % (e, ' '.join(cmd)))
+        proc.wait()
+        stderr = proc.stderr.read()
+        stdout = proc.stdout.read()
+        if status_error in stderr:
+            return False
+        root_path = stdout.strip()
+        setup_py = os.path.join(root_path, 'setup.py')
+        if not os.path.isfile(setup_py):
+            return False
+        if setup_project_name(setup_py) != dist.project_name:
+            return False
+        return True
+
+
     def parse_vcs_bundle_file(self, content):
         url = rev = None
         for line in content.splitlines():

pip/vcs/subversion.py

@@ -24,6 +24,13 @@ class Subversion(VersionControl):
     guide = ('# This was an svn checkout; to make it a checkout again run:\n'
             'svn checkout --force -r %(rev)s %(url)s .\n')
 
+    def check_repository(self, dist):
+        svn_path = os.path.join(dist.location, self.dirname)
+        if os.path.exists(svn_path) and os.path.isdir(svn_path):
+            return True
+        else:
+            return False
+
     def get_info(self, location):
         """Returns (url, revision), where both are strings"""
         assert not location.rstrip('/').endswith(self.dirname), 'Bad directory: %s' % location