Expand ~ in the wheel cache directory

CHANGES.txt

@@ -10,6 +10,9 @@
   options interleaved with requirements, version specifiers etc in
   ``requirements`` files. (:pull:`2841`)
 
+* Expand ``~`` in the cache directory when caching wheels, fixes :issue:`2816`.
+
+
 **7.0.1 (2015-05-22)**
 
 * Don't build and cache wheels for non-editable installations from VCSs.

pip/wheel.py

@@ -10,6 +10,7 @@ import functools
 import hashlib
 import logging
 import os
+import os.path
 import re
 import shutil
 import stat
@@ -54,7 +55,7 @@ class WheelCache(object):
         :param format_control: A pip.index.FormatControl object to limit
             binaries being read from the cache.
         """
-        self._cache_dir = cache_dir
+        self._cache_dir = os.path.expanduser(cache_dir)
         self._format_control = format_control
 
     def cached_wheel(self, link, package_name):

tests/unit/test_wheel.py

@@ -390,3 +390,10 @@ class TestWheelBuilder(object):
             wb.build()
             assert "due to being editable" in caplog.text()
             assert mock_build_one.mock_calls == []
+
+
+class TestWheelCache:
+
+    def test_expands_path(self):
+        wc = wheel.WheelCache("~/.foo/", None)
+        assert wc._cache_dir == os.path.expanduser("~/.foo/")