From 5b5ac9494ccd8b7223232b8c640fffb017071000 2020-06-02 13:07:45
From: Min RK <benjaminrk@gmail.com>
Date: 2020-06-02 13:07:45
Subject: [PATCH] use $SHELL in system_piped

we already use this in our call to subprocess.call in system_raw used in the terminal

this makes kernel behavior better match terminal IPython

For an example that used to be different:

    !wc -l <(pwd)

with `SHELL=bash`

---

diff --git a/IPython/utils/_process_posix.py b/IPython/utils/_process_posix.py
index f3f93f7..a11cad7 100644
--- a/IPython/utils/_process_posix.py
+++ b/IPython/utils/_process_posix.py
@@ -59,11 +59,12 @@ class ProcessHandler(object):
 
     @property
     def sh(self):
-        if self._sh is None:        
-            self._sh = pexpect.which('sh')
+        if self._sh is None:
+            shell_name = os.environ.get("SHELL", "sh")
+            self._sh = pexpect.which(shell_name)
             if self._sh is None:
-                raise OSError('"sh" shell not found')
-        
+                raise OSError('"{}" shell not found'.format(shell_name))
+
         return self._sh
 
     def __init__(self, logfile=None, read_timeout=None, terminate_timeout=None):