why doesn't pip install package when using tox?
<p>I created a package the structure of which is given here.</p>

<pre><code>packagename
   -- packagename
         -- __init__.py
   -- setup.py
</code></pre>

<p>The package installed correctly and I checked with 'pip freeze'</p>

<p>I am trying to use this package in another module with tox </p>

<p>tox.ini</p>

<pre><code> [tox]
  envlist = dev
 [default-dependencies]
  deps = packagename
 [testenv:dev]
  deps = {[default-dependencies]deps}
  pip_pre=True
  ignore_errors=True
  commands = py.test blah
</code></pre>

<p>when I try to this using </p>

<pre><code>tox -e dev
</code></pre>

<p>I get this error message</p>

<pre><code>Collecting packagename
Could not find a version that satisfies the requirement packagename (from versions: )
No matching distribution found for packagename
v = InvocationError('/Users/***/.tox/dev/bin/pip install --pre dlb_dcp_csaf')
</code></pre>

<p>However, everything is good when I install like this</p>

<pre><code> pip install --pre packagename 
</code></pre>

<p>I checked the pip version for both </p>

<pre><code> pip 8.1.1 from /usr/local/lib/python2.7/site-packages (python 2.7)
 pip 8.1.1 from /Users/***/.tox/dev/lib/python2.7/site-packages (python 2.7)
</code></pre>

<p>Can anyone please help why I couldn't install the package using tox but can install using pip manually?</p>