python site.py that loads pth files anywhere on PYTHONPATH

This file is normally created by easy_install / distutils, but removed
and packaged separately to avoid collisions and allow for more use cases.

svn path=/nixpkgs/branches/stdenv-updates/; revision=32579

2 files changed, 115 insertions, 0 deletions

diff --git a/pkgs/development/python-modules/site/default.nix b/pkgs/development/python-modules/site/default.nix
new file mode 100644
index 00000000000..98a14850dbe
--- /dev/null
+++ b/pkgs/development/python-modules/site/default.nix
@@ -0,0 +1,33 @@
+{ stdenv, python }:
+
+stdenv.mkDerivation rec {
+  name = "site-1.0";
+
+  unpackPhase = "true";
+
+  buildInputs = [ python ];
+
+  installPhase =
+    ''
+      dst=$out/lib/${python.libPrefix}/site-packages
+      mkdir -p $dst
+      cat ${./site.py} >> $dst/site.py
+    '';
+
+  meta = {
+      description = "Enable processing of pth files anywhere in PYTHONPATH";
+      longDescription = ''
+        This file is normally created by easy_install / distutils in
+        site-packages and overrides python's default site.py. It adds
+        all parts of PYTHONPATH as site directories, which means pth
+        files are processed in them. We remove the normally created
+        site.py's and package it separately instead as it would cause
+        collisions.
+
+        For each module we have a pth file listing the module and all
+        its dependencies and we include python-site into the
+        PYTHONPATH of wrapped python programs so they can find their
+        dependencies.
+      '';
+  };
+}
diff --git a/pkgs/development/python-modules/site/site.py b/pkgs/development/python-modules/site/site.py
new file mode 100644
index 00000000000..b233222e1f6
--- /dev/null
+++ b/pkgs/development/python-modules/site/site.py
@@ -0,0 +1,82 @@
+def __boot():
+    import sys, imp, os, os.path
+    PYTHONPATH = os.environ.get('PYTHONPATH')
+    if PYTHONPATH is None or (sys.platform=='win32' and not PYTHONPATH):
+        PYTHONPATH = []
+    else:
+        PYTHONPATH = PYTHONPATH.split(os.pathsep)
+
+    pic = getattr(sys,'path_importer_cache',{})
+    stdpath = sys.path[len(PYTHONPATH):]
+    mydir = os.path.dirname(__file__)
+    #print "searching",stdpath,sys.path
+
+    for item in stdpath:
+        if item==mydir or not item:
+            continue    # skip if current dir. on Windows, or my own directory
+        importer = pic.get(item)
+        if importer is not None:
+            loader = importer.find_module('site')
+            if loader is not None:
+                # This should actually reload the current module
+                loader.load_module('site')
+                break
+        else:
+            try:
+                stream, path, descr = imp.find_module('site',[item])
+            except ImportError:
+                continue
+            if stream is None:
+                continue
+            try:
+                # This should actually reload the current module
+                imp.load_module('site',stream,path,descr)
+            finally:
+                stream.close()
+            break
+    else:
+        raise ImportError("Couldn't find the real 'site' module")
+
+    #print "loaded", __file__
+
+    known_paths = dict([(makepath(item)[1],1) for item in sys.path]) # 2.2 comp
+
+    oldpos = getattr(sys,'__egginsert',0)   # save old insertion position
+    sys.__egginsert = 0                     # and reset the current one
+
+    for item in PYTHONPATH:
+        addsitedir(item)
+
+    sys.__egginsert += oldpos           # restore effective old position
+
+    d,nd = makepath(stdpath[0])
+    insert_at = None
+    new_path = []
+
+    for item in sys.path:
+        p,np = makepath(item)
+
+        if np==nd and insert_at is None:
+            # We've hit the first 'system' path entry, so added entries go here
+            insert_at = len(new_path)
+
+        if np in known_paths or insert_at is None:
+            new_path.append(item)
+        else:
+            # new path after the insert point, back-insert it
+            new_path.insert(insert_at, item)
+            insert_at += 1
+
+    sys.path[:] = new_path
+
+if __name__=='site':
+    __boot()
+    del __boot
+
+
+
+
+
+
+
+