From ccf22d5ae2620c50640a9a45bb68ed45b0037fc3 Mon Sep 17 00:00:00 2001
From: Allen Li <darkfeline@felesatra.moe>
Date: Wed, 22 Nov 2017 00:18:37 -0800
Subject: [PATCH] Prompt for confirmation before replacing existing virtualenv

Fixes https://github.com/kennethreitz/pipenv/issues/997
---
 pipenv/cli.py | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/pipenv/cli.py b/pipenv/cli.py
index c9f97e5c..0c1b2397 100644
--- a/pipenv/cli.py
+++ b/pipenv/cli.py
@@ -544,6 +544,9 @@ def ensure_python(three=None, python=None):
 def ensure_virtualenv(three=None, python=None, site_packages=False):
     """Creates a virtualenv, if one doesn't exist."""
 
+    def abort():
+        sys.exit(1)
+
     global USING_DEFAULT_PYTHON
 
     if not project.virtualenv_exists:
@@ -580,6 +583,12 @@ def ensure_virtualenv(three=None, python=None, site_packages=False):
         ensure_python(three=three, python=python)
 
         click.echo(crayons.red('Virtualenv already exists!'), err=True)
+        # If VIRTUAL_ENV is set, there is a possibility that we are
+        # going to remove the active virtualenv that the user cares
+        # about, so confirm first.
+        if 'VIRTUAL_ENV' in os.environ:
+            if not (PIPENV_YES or click.confirm('Remove existing virtualenv?', default=True)):
+                abort()
         click.echo(crayons.normal(u'Removing existing virtualenv…', bold=True), err=True)
 
         # Remove the virtualenv.