use typeset instead of local and provide attribution for the original fix

Author: dhellmann

docs/en/history.rst

@@ -2,6 +2,12 @@
 Release History
 ===============
 
+dev
+
+  - Make ``project_dir`` a local variable so that
+    :ref:`command-cdproject` does not interfere with other variables
+    the user might have set. (contributed by :bbuser:`slackorama`)
+
 3.1
 
   - Fix a problem with activation hooks when associating a new

virtualenvwrapper.sh

@@ -918,7 +918,7 @@ function cdproject {
     virtualenvwrapper_verify_active_environment || return 1
     if [ -f "$VIRTUAL_ENV/$VIRTUALENVWRAPPER_PROJECT_FILENAME" ]
     then
-        local project_dir=$(cat "$VIRTUAL_ENV/$VIRTUALENVWRAPPER_PROJECT_FILENAME")
+        typeset project_dir=$(cat "$VIRTUAL_ENV/$VIRTUALENVWRAPPER_PROJECT_FILENAME")
         if [ ! -z "$project_dir" ]
         then
             cd "$project_dir"