Add {envsitepackagesdir} substitution. Closes #72.

5 files changed, 65 insertions, 17 deletions

diff --git a/CHANGELOG b/CHANGELOG
index 16f3431..278876e 100755
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,6 +1,8 @@
 1.4.3.dev
 -----------------
 
+- substitute {envsitepackagesdir} with the package installation directory (closes #72)
+
 - issue #70 remove PYTHONDONTWRITEBYTECODE workaround now that
   virtualenv behaves properly (thanks g2p)
 
diff --git a/doc/config.txt b/doc/config.txt
index 8cdcfcd..8829d1b 100644
--- a/doc/config.txt
+++ b/doc/config.txt
@@ -199,6 +199,9 @@ substitutions for virtualenv-related sections
     directory of the virtualenv hierarchy
 ``{envbindir}``
     directory where executables are located
+``{envsitepackagesdir}``
+    directory where packages are installed.
+    Note that architecture-specific files may appear in a different directory.
 ``{envtmpdir}``
     the environment temporary directory
 ``{envlogdir}``
diff --git a/tests/test_z_cmdline.py b/tests/test_z_cmdline.py
index 1b397c7..fcded04 100644
--- a/tests/test_z_cmdline.py
+++ b/tests/test_z_cmdline.py
@@ -438,3 +438,11 @@ def test_sdist_latest(tmpdir, newconfig):
     session = Session(config)
     sdist_path = session.sdist()
     assert sdist_path == p
+
+def test_envsitepackagesdir(cmd, initproj):
+    initproj("pkg512-0.0.5", filedefs={
+        'tox.ini': """
+        commands=
+            grep '__version__.*=.*0\.0\.5' {envsitepackagesdir}/pkg512/__init__.py
+    """})
+    result = cmd.run("tox")
diff --git a/tox/_config.py b/tox/_config.py
index e02e25e..7a9a090 100644
--- a/tox/_config.py
+++ b/tox/_config.py
@@ -1,9 +1,12 @@
 import argparse
+import distutils.sysconfig
 import os
 import sys
 import re
 import shlex
 import string
+import subprocess
+import textwrap
 
 import py
 
@@ -34,7 +37,12 @@ def parseconfig(args=None, pkg=None):
                 break
         else:
             feedback("toxini file %r not found" %(basename), sysexit=True)
-    parseini(config, inipath)
+    try:
+        parseini(config, inipath)
+    except tox.exception.InterpreterNotFound:
+        exn = sys.exc_info()[1]
+        # Use stdout to match test expectations
+        py.builtin.print_("ERROR: " + str(exn))
     return config
 
 def feedback(msg, sysexit=False):
@@ -114,6 +122,45 @@ class VenvConfig:
             name = "python"
         return self.envbindir.join(name)
 
+    @property
+    def envsitepackagesdir(self):
+        print_envsitepackagesdir = textwrap.dedent("""
+        import sys
+        from distutils.sysconfig import get_python_lib
+        sys.stdout.write(get_python_lib(prefix=sys.argv[1]))
+        """)
+
+        exe = self.getsupportedinterpreter()
+        # can't use check_output until py27
+        proc = subprocess.Popen(
+            [str(exe), '-c', print_envsitepackagesdir, str(self.envdir)],
+            stdout=subprocess.PIPE)
+        odata, edata = proc.communicate()
+        if proc.returncode:
+            raise tox.exception.UnsupportedInterpreter(
+                "Error getting site-packages from %s" % self.basepython)
+        return odata
+
+    def getconfigexecutable(self):
+        from tox._venv import find_executable
+
+        python = self.basepython
+        if not python:
+            python = sys.executable
+        x = find_executable(str(python))
+        if x:
+            x = x.realpath()
+        return x
+
+    def getsupportedinterpreter(self):
+        if sys.platform == "win32" and self.basepython and \
+                "jython" in self.basepython:
+            raise tox.exception.UnsupportedInterpreter(
+                "Jython/Windows does not support installing scripts")
+        config_executable = self.getconfigexecutable()
+        if not config_executable:
+            raise tox.exception.InterpreterNotFound(self.basepython)
+        return config_executable
 testenvprefix = "testenv:"
 
 class parseini:
@@ -205,7 +252,8 @@ class parseini:
             bp = sys.executable
         vc.basepython = reader.getdefault(section, "basepython", bp)
         reader.addsubstitions(envdir=vc.envdir, envname=vc.envname,
-                              envbindir=vc.envbindir, envpython=vc.envpython)
+                              envbindir=vc.envbindir, envpython=vc.envpython,
+                              envsitepackagesdir=vc.envsitepackagesdir)
         vc.envtmpdir = reader.getpath(section, "tmpdir", "{envdir}/tmp")
         vc.envlogdir = reader.getpath(section, "envlogdir", "{envdir}/log")
         reader.addsubstitions(envlogdir=vc.envlogdir, envtmpdir=vc.envtmpdir)
diff --git a/tox/_venv.py b/tox/_venv.py
index 40047f3..2faa087 100644
--- a/tox/_venv.py
+++ b/tox/_venv.py
@@ -146,23 +146,10 @@ class VirtualEnv(object):
         return l
 
     def getconfigexecutable(self):
-        python = self.envconfig.basepython
-        if not python:
-            python = sys.executable
-        x = find_executable(str(python))
-        if x:
-            x = x.realpath()
-        return x
+        return self.envconfig.getconfigexecutable()
 
     def getsupportedinterpreter(self):
-        if sys.platform == "win32" and self.envconfig.basepython and \
-                "jython" in self.envconfig.basepython:
-            raise tox.exception.UnsupportedInterpreter(
-                "Jython/Windows does not support installing scripts")
-        config_executable = self.getconfigexecutable()
-        if not config_executable:
-            raise tox.exception.InterpreterNotFound(self.envconfig.basepython)
-        return config_executable
+        return self.envconfig.getsupportedinterpreter()
 
     def create(self, action=None):
         #if self.getcommandpath("activate").dirpath().check():