diff --git a/tox.ini b/tox.ini
index 603eafb..fcc58b1 100644
--- a/tox.ini
+++ b/tox.ini
@@ -36,6 +36,9 @@ description = Unit tests installed
 
 changedir = test_01_installed
 
+whitelist_externals = 
+    cp
+
 # Appveyor will set the WEXPECT_SPAWN_CLASS to run the proper configuration for each run.
 passenv = 
     WEXPECT_*
@@ -52,11 +55,16 @@ commands =
 # Test if wexpect working with pyinstaller. See #12 for more details.
 description = Unit tests pyinstaller
 
-# Appveyor will set the WEXPECT_SPAWN_CLASS to run the proper configuration for each run.
-passenv = 
-    WEXPECT_*
+whitelist_externals = 
+    pyinstaller
+    pyinstaller_test
+    
+setenv =
+    WEXPECT_SPAWN_CLASS=SpawnPipe
     
 commands =
+    # install the dependencies:
+    pip install .[test]
     
     # create wexpect executable for console-reader.
     pyinstaller wexpect.spec