Use less readlink for osx peeps.

pre_commit/resources/pre-commit-hook

@@ -2,7 +2,9 @@
 # This is a randomish md5 to identify this script
 # 4d9958c90bc262f47553e2c073f14cfe
 
-HERE=$(dirname $(readlink -f "$0"))
+pushd `dirname $0` > /dev/null
+HERE=`pwd`
+popd > /dev/null
 
 retv=0
 

tests/commands/install_uninstall_test.py

@@ -100,13 +100,23 @@ def _get_commit_output(tmpdir_factory, touch_file='foo'):
     )[:2]
 
 
+# osx does this different :(
+FILES_CHANGED = (
+    r'('
+    r' 1 file changed, 0 insertions\(\+\), 0 deletions\(-\)\n'
+    r'|'
+    r' 0 files changed\n'
+    r')'
+)
+
+
 NORMAL_PRE_COMMIT_RUN = re.compile(
     r'^\[INFO\] Installing environment for .+\.\n'
     r'\[INFO\] Once installed this environment will be reused\.\n'
     r'\[INFO\] This may take a few minutes\.\.\.\n'
     r'Bash hook\.+Passed\n'
-    r'\[master [a-f0-9]{7}\] Commit!\n'
-    r' 0 files changed\n'
+    r'\[master [a-f0-9]{7}\] Commit!\n' +
+    FILES_CHANGED +
     r' create mode 100644 foo\n$'
 )
 
@@ -174,8 +184,8 @@ def test_failing_hooks_returns_nonzero(tmpdir_factory):
 
 EXISTING_COMMIT_RUN = re.compile(
     r'^legacy hook\n'
-    r'\[master [a-f0-9]{7}\] Commit!\n'
-    r' 0 files changed\n'
+    r'\[master [a-f0-9]{7}\] Commit!\n' +
+    FILES_CHANGED +
     r' create mode 100644 baz\n$'
 )