1 files changed, 62 insertions, 0 deletions
diff --git a/nixpkgs/pkgs/development/python-modules/virtualenv/virtualenv-change-prefix.patch b/nixpkgs/pkgs/development/python-modules/virtualenv/virtualenv-change-prefix.patch
new file mode 100644
index 000000000000..4378e00bb1fc
--- /dev/null
+++ b/nixpkgs/pkgs/development/python-modules/virtualenv/virtualenv-change-prefix.patch
@@ -0,0 +1,62 @@
+Without this patch `virtualenv --python=python2.7 .` fails with an
+error because it notices that the python readline.so is not in the
+same path as python2.7. I assume this is to avoid copying the wrong
+file on systems where it is possible to find incompatible libraries by
+accident. Adding "/nix/store" to the prefix fixes this problem.
+
+A sitecustomize.py is created in the virtualenv which makes libraries
+from the python specified by the --python argument available to the
+virtualenv. For example, this makes readline and sqlite3 available
+when a wrapped python is specified. If no --python argument is passed,
+it will only add the path to the python used when building
+`virtualenv`, which is the unwrapped python, so sqlite3 won't be
+available.
+
+
+diff --git a/virtualenv.py b/virtualenv.py
+index bcf3225..3530997 100755
+--- a/virtualenv.py
++++ b/virtualenv.py
+@@ -1163,20 +1163,7 @@ def path_locations(home_dir, dry_run=False):
+ 
+ 
+ def change_prefix(filename, dst_prefix):
+-    prefixes = [sys.prefix]
+-
+-    if IS_DARWIN:
+-        prefixes.extend(
+-            (
+-                os.path.join("/Library/Python", sys.version[:3], "site-packages"),
+-                os.path.join(sys.prefix, "Extras", "lib", "python"),
+-                os.path.join("~", "Library", "Python", sys.version[:3], "site-packages"),
+-                # Python 2.6 no-frameworks
+-                os.path.join("~", ".local", "lib", "python", sys.version[:3], "site-packages"),
+-                # System Python 2.7 on OSX Mountain Lion
+-                os.path.join("~", "Library", "Python", sys.version[:3], "lib", "python", "site-packages"),
+-            )
+-        )
++    prefixes = ["/nix/store", sys.prefix]
+ 
+     if hasattr(sys, "real_prefix"):
+         prefixes.append(sys.real_prefix)
+@@ -1199,6 +1186,8 @@ def change_prefix(filename, dst_prefix):
+             if src_prefix != os.sep:  # sys.prefix == "/"
+                 assert relative_path[0] == os.sep
+                 relative_path = relative_path[1:]
++                if src_prefix == "/nix/store":
++                    relative_path = "/".join(relative_path.split("/")[1:])
+             return join(dst_prefix, relative_path)
+     assert False, "Filename {} does not start with any of these prefixes: {}".format(filename, prefixes)
+ 
+@@ -1375,6 +1364,11 @@ def install_python(home_dir, lib_dir, inc_dir, bin_dir, site_packages, clear, sy
+     site_filename_dst = change_prefix(site_filename, home_dir)
+     site_dir = os.path.dirname(site_filename_dst)
+     writefile(site_filename_dst, SITE_PY)
++    wrapper_path = join(prefix, "lib", PY_VERSION, "site-packages")
++    writefile(
++        join(site_dir, 'sitecustomize.py',),
++        "import sys; sys.path.append('%s')" % wrapper_path
++    )
+     writefile(join(site_dir, "orig-prefix.txt"), prefix)
+     site_packages_filename = join(site_dir, "no-global-site-packages.txt")
+     if not site_packages: