commit e87c83d95bb91acdca92202e94488ca51a70e059
Author: Domen Kožar <domen@dev.si>
Date:   Mon Nov 16 17:39:44 2015 +0100

    WIP

diff --git a/pip/commands/install.py b/pip/commands/install.py
index dbcf100..05d5a08 100644
--- a/pip/commands/install.py
+++ b/pip/commands/install.py
@@ -139,6 +139,13 @@ class InstallCommand(RequirementCommand):
                  "directory.")
 
         cmd_opts.add_option(
+            '--prefix',
+            dest='prefix_path',
+            metavar='dir',
+            default=None,
+            help="Installation prefix where lib, bin and other top-level folders are placed")
+
+        cmd_opts.add_option(
             "--compile",
             action="store_true",
             dest="compile",
@@ -309,6 +316,7 @@ class InstallCommand(RequirementCommand):
                             install_options,
                             global_options,
                             root=options.root_path,
+                            prefix=options.prefix_path,
                         )
                         reqs = sorted(
                             requirement_set.successfully_installed,
diff --git a/pip/locations.py b/pip/locations.py
index 4e6f65d..43aeb1f 100644
--- a/pip/locations.py
+++ b/pip/locations.py
@@ -163,7 +163,7 @@ site_config_files = [
 
 
 def distutils_scheme(dist_name, user=False, home=None, root=None,
-                     isolated=False):
+                     isolated=False, prefix=None):
     """
     Return a distutils install scheme
     """
@@ -187,6 +187,8 @@ def distutils_scheme(dist_name, user=False, home=None, root=None,
     i.user = user or i.user
     if user:
         i.prefix = ""
+    else:
+        i.prefix = prefix or i.prefix
     i.home = home or i.home
     i.root = root or i.root
     i.finalize_options()
diff --git a/pip/req/req_install.py b/pip/req/req_install.py
index 7c5bf8f..6f80a18 100644
--- a/pip/req/req_install.py
+++ b/pip/req/req_install.py
@@ -792,7 +792,7 @@ exec(compile(
         else:
             return True
 
-    def install(self, install_options, global_options=[], root=None):
+    def install(self, install_options, global_options=[], root=None, prefix=None):
         if self.editable:
             self.install_editable(install_options, global_options)
             return
@@ -800,7 +800,7 @@ exec(compile(
             version = pip.wheel.wheel_version(self.source_dir)
             pip.wheel.check_compatibility(version, self.name)
 
-            self.move_wheel_files(self.source_dir, root=root)
+            self.move_wheel_files(self.source_dir, root=root, prefix=prefix)
             self.install_succeeded = True
             return
 
@@ -833,6 +833,8 @@ exec(compile(
 
             if root is not None:
                 install_args += ['--root', root]
+            if prefix is not None:
+                install_args += ['--prefix', prefix]
 
             if self.pycompile:
                 install_args += ["--compile"]
@@ -988,12 +990,13 @@ exec(compile(
     def is_wheel(self):
         return self.link and self.link.is_wheel
 
-    def move_wheel_files(self, wheeldir, root=None):
+    def move_wheel_files(self, wheeldir, root=None, prefix=None):
         move_wheel_files(
             self.name, self.req, wheeldir,
             user=self.use_user_site,
             home=self.target_dir,
             root=root,
+            prefix=prefix,
             pycompile=self.pycompile,
             isolated=self.isolated,
         )
diff --git a/pip/wheel.py b/pip/wheel.py
index 403f48b..14eb141 100644
--- a/pip/wheel.py
+++ b/pip/wheel.py
@@ -234,12 +234,12 @@ def get_entrypoints(filename):
 
 
 def move_wheel_files(name, req, wheeldir, user=False, home=None, root=None,
-                     pycompile=True, scheme=None, isolated=False):
+                     pycompile=True, scheme=None, isolated=False, prefix=None):
     """Install a wheel"""
 
     if not scheme:
         scheme = distutils_scheme(
-            name, user=user, home=home, root=root, isolated=isolated
+            name, user=user, home=home, root=root, isolated=isolated, prefix=prefix,
         )
 
     if root_is_purelib(name, wheeldir):
diff --git a/pip/req/req_install.py b/pip/req/req_install.py
index 51bf4a7..e2e285e 100644
--- a/pip/req/req_install.py
+++ b/pip/req/req_install.py
@@ -795,7 +795,7 @@ exec(compile(
     def install(self, install_options, global_options=[], root=None,
                 prefix=None):
         if self.editable:
-            self.install_editable(install_options, global_options)
+            self.install_editable(install_options, global_options, prefix=prefix)
             return
         if self.is_wheel:
             version = pip.wheel.wheel_version(self.source_dir)
@@ -929,12 +929,16 @@ exec(compile(
             rmtree(self._temp_build_dir)
         self._temp_build_dir = None
 
-    def install_editable(self, install_options, global_options=()):
+    def install_editable(self, install_options, global_options=(), prefix=None):
         logger.info('Running setup.py develop for %s', self.name)
 
         if self.isolated:
             global_options = list(global_options) + ["--no-user-cfg"]
 
+        if prefix:
+            prefix_param = ['--prefix={0}'.format(prefix)]
+            install_options = list(install_options) + prefix_param
+
         with indent_log():
             # FIXME: should we do --install-headers here too?
             cwd = self.source_dir