From 471dccada3a0c9ad4cd44a581c4b8c460d26af0b Mon Sep 17 00:00:00 2001
From: Tal Einat <taleinat@gmail.com>
Date: Tue, 6 Aug 2019 00:02:26 +0300
Subject: [PATCH] bpo-37768: IDLE: show help(object) output in a text viewing
 window

---
 Lib/idlelib/pyshell.py                        | 19 ++++++++++++++-----
 Lib/idlelib/run.py                            |  5 ++---
 .../2019-08-05-23-58-03.bpo-37768.dM-QL8.rst  |  2 ++
 3 files changed, 18 insertions(+), 8 deletions(-)
 create mode 100644 Misc/NEWS.d/next/IDLE/2019-08-05-23-58-03.bpo-37768.dM-QL8.rst

diff --git a/Lib/idlelib/pyshell.py b/Lib/idlelib/pyshell.py
index ea9465568bd93f..702ea0c624ee4a 100755
--- a/Lib/idlelib/pyshell.py
+++ b/Lib/idlelib/pyshell.py
@@ -55,6 +55,7 @@
 from idlelib.outwin import OutputWindow
 from idlelib import rpc
 from idlelib.run import idle_formatwarning, PseudoInputFile, PseudoOutputFile
+from idlelib.textview import view_text
 from idlelib.undo import UndoDelegator
 
 HOST = '127.0.0.1' # python execution server on localhost loopback
@@ -906,11 +907,9 @@ def __init__(self, flist=None):
             sys.stderr = self.stderr
             sys.stdin = self.stdin
         try:
-            # page help() text to shell.
-            import pydoc # import must be done here to capture i/o rebinding.
-            # XXX KBK 27Dec07 use text viewer someday, but must work w/o subproc
-            pydoc.pager = pydoc.plainpager
-        except:
+            import pydoc  # import must be done here to capture i/o rebinding.
+            pydoc.pager = self.pager
+        except Exception:
             sys.stderr = sys.__stderr__
             raise
         #
@@ -918,6 +917,16 @@ def __init__(self, flist=None):
         #
         self.pollinterval = 50  # millisec
 
+    def pager(self, text):
+        """pydoc.pager compatible callback for showing help() output."""
+        import pydoc  # Import here to avoid i/o binding issues.
+        text = pydoc.plain(text)  # Remove fancy pydoc formatting.
+        try:
+            title, text = text.split(':\n\n', 1)
+        except ValueError:
+            title = "Help"
+        view_text(self.text, title, text, modal=False)
+
     def get_standard_extension_names(self):
         return idleConf.GetExtensions(shell_only=True)
 
diff --git a/Lib/idlelib/run.py b/Lib/idlelib/run.py
index 41e0ded4402937..de33ecbca6dd91 100644
--- a/Lib/idlelib/run.py
+++ b/Lib/idlelib/run.py
@@ -503,9 +503,8 @@ def handle(self):
                 iomenu.encoding)
 
         sys.displayhook = rpc.displayhook
-        # page help() text to shell.
-        import pydoc # import must be done here to capture i/o binding
-        pydoc.pager = pydoc.plainpager
+        import pydoc  # import must be done here to capture i/o binding
+        pydoc.pager = self.console.pager
 
         # Keep a reference to stdin so that it won't try to exit IDLE if
         # sys.stdin gets changed from within IDLE's shell. See issue17838.
diff --git a/Misc/NEWS.d/next/IDLE/2019-08-05-23-58-03.bpo-37768.dM-QL8.rst b/Misc/NEWS.d/next/IDLE/2019-08-05-23-58-03.bpo-37768.dM-QL8.rst
new file mode 100644
index 00000000000000..9d7ef892fe0961
--- /dev/null
+++ b/Misc/NEWS.d/next/IDLE/2019-08-05-23-58-03.bpo-37768.dM-QL8.rst
@@ -0,0 +1,2 @@
+``help(object)`` now shows the help text in a separate text viewing window
+rather than in the shell output.