Merge pull request #2369 from pypa/bugfix-2273

Make `PIPENV_VIRTUALENV` global

pipenv/core.py

@@ -1261,6 +1261,7 @@ def do_init(
     pypi_mirror=None,
 ):
     """Executes the init functionality."""
+    global PIPENV_VIRTUALENV
     if not system:
         if not project.virtualenv_exists:
             try:
@@ -1292,7 +1293,7 @@ def do_init(
                 )
                 requirements_dir.cleanup()
                 sys.exit(1)
-            elif system or allow_global:
+            elif (system or allow_global) and not (PIPENV_VIRTUALENV):
                 click.echo(
                     crayons.red(
                         u'Pipfile.lock ({0}) out of date, but installation '
@@ -1321,7 +1322,7 @@ def do_init(
     if not project.lockfile_exists and not skip_lock:
         # Unless we're in a virtualenv not managed by pipenv, abort if we're
         # using the system's python.
-        if (system or allow_global) and not PIPENV_VIRTUALENV:
+        if (system or allow_global) and not (PIPENV_VIRTUALENV):
             click.echo(
                 '{0}: --system is intended to be used for Pipfile installation, '
                 'not installation of specific packages. Aborting.'.format(
@@ -1793,6 +1794,7 @@ def do_install(
         keep_outdated = project.settings.get('keep_outdated')
     remote = requirements and is_valid_url(requirements)
     # Warn and exit if --system is used without a pipfile.
+    global PIPENV_VIRTUALENV
     if system and package_name and not PIPENV_VIRTUALENV:
         click.echo(
             '{0}: --system is intended to be used for Pipfile installation, '