From 7ce51159f4846590d50b844a69b36cf31c7d1785 Mon Sep 17 00:00:00 2001
From: Nate Prewitt <Nate.Prewitt@gmail.com>
Date: Wed, 1 Mar 2017 09:08:59 -0700
Subject: [PATCH] Only spawn shell once

---
 pipenv/cli.py | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/pipenv/cli.py b/pipenv/cli.py
index 400ada6e..19dd947c 100644
--- a/pipenv/cli.py
+++ b/pipenv/cli.py
@@ -868,6 +868,10 @@ def shell(three=None, python=False, compat=False, shell_args=None):
     # Ensure that virtualenv is available.
     ensure_project(three=three, python=python, validate=False)
 
+    if 'PIPENV_ACTIVE' in os.environ:
+        click.echo(crayons.yellow('Shell already activated. No action taken to avoid nested environments.'))
+        return
+
     # Set an environment variable, so we know we're in the environment.
     os.environ['PIPENV_ACTIVE'] = '1'