Use powershell when it is being used

- Call pew workon function directly instead of using suprocess call
- Allow increased depth when searching for shells

pipenv/core.py

@@ -2028,6 +2028,7 @@ def do_uninstall(
 
 
 def do_shell(three=None, python=False, fancy=False, shell_args=None):
+    from pipenv.patched.pew import pew
 
     # Ensure that virtualenv is available.
     ensure_project(three=three, python=python, validate=False)
@@ -2097,14 +2098,13 @@ def do_shell(three=None, python=False, fancy=False, shell_args=None):
 
     # Windows!
     except AttributeError:
-        import subprocess
+        # import subprocess
         # Tell pew to use the project directory as its workon_home
         with temp_environ():
             if PIPENV_VENV_IN_PROJECT:
                 os.environ['WORKON_HOME'] = project.project_directory
-            p = subprocess.Popen([cmd] + list(args), shell=True, universal_newlines=True)
-            p.communicate()
-            sys.exit(p.returncode)
+            pew.workon_cmd([workon_name])
+            sys.exit(0)
 
     # Activate the virtualenv if in compatibility mode.
     if compat:

pipenv/patched/pew/_win_utils.py

@@ -14,7 +14,7 @@ from ctypes.wintypes import DWORD, LONG
 
 ERROR_NO_MORE_FILES = 18
 INVALID_HANDLE_VALUE = c_void_p(-1).value
-
+SHELL_NAMES = ['cmd', 'powershell', 'cmder']
 
 class PROCESSENTRY32(Structure):
     _fields_ = [
@@ -92,22 +92,7 @@ def get_all_processes():
     return pids
 
 
-def get_grandparent_process(pid=None):
-    """Get grandparent process name of the supplied pid or os.getpid().
-
-    :param int pid: The pid to track.
-    :return: Name of the grandparent process.
-    """
-    if not pid:
-        pid = os.getpid()
-    processes = get_all_processes()
-    ppid = processes[pid]['parent_pid']
-    parent = processes[ppid]
-    grandparent = processes[parent['parent_pid']]
-    return grandparent['executable']
-
-
-def get_shell(pid=None):
+def get_shell(pid=None, max_depth=4):
     """Get the shell that the supplied pid or os.getpid() is running in.
     """
     if not pid:
@@ -116,11 +101,11 @@ def get_shell(pid=None):
 
     def check_parent(pid, lvl=0):
         ppid = processes[pid].get('parent_pid')
-        if ppid and processes[ppid]['executable'].lower().rsplit('.', 1)[0] in ['cmd', 'powershell']:
+        if ppid and processes[ppid]['executable'].lower().rsplit('.', 1)[0] in SHELL_NAMES:
             return processes[ppid]['executable']
-        if lvl >= 4:
+        if lvl >= max_depth:
             return
         return check_parent(ppid, lvl=lvl+1)
-    if processes[pid]['executable'].lower().rsplit('.', 1)[-1] in ['cmd', 'powershell']:
+    if processes[pid]['executable'].lower().rsplit('.', 1)[0] in SHELL_NAMES:
         return processes[pid]['executable']
     return check_parent(pid)