From fbc3c3c2bed34350e0dde4771805c51b80f2e410 Mon Sep 17 00:00:00 2001
From: Georg Brandl <georg@python.org>
Date: Sun, 13 Oct 2013 21:49:06 +0200
Subject: [PATCH] Closes #17730: in code.interact(), when banner="", do not
 print anything.

Also adds tests for banner printing.
---
 Doc/library/code.rst         |  5 ++++-
 Lib/code.py                  |  2 +-
 Lib/test/test_code_module.py | 14 ++++++++++++++
 3 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/Doc/library/code.rst b/Doc/library/code.rst
index 56214b9f722..d1f94755ee0 100644
--- a/Doc/library/code.rst
+++ b/Doc/library/code.rst
@@ -132,12 +132,15 @@ interpreter objects as well as the following additions.
 
 .. method:: InteractiveConsole.interact(banner=None)
 
-   Closely emulate the interactive Python console. The optional banner argument
+   Closely emulate the interactive Python console. The optional *banner* argument
    specify the banner to print before the first interaction; by default it prints a
    banner similar to the one printed by the standard Python interpreter, followed
    by the class name of the console object in parentheses (so as not to confuse
    this with the real interpreter -- since it's so close!).
 
+   .. versionchanged:: 3.4
+      To suppress printing any banner, pass an empty string.
+
 
 .. method:: InteractiveConsole.push(line)
 
diff --git a/Lib/code.py b/Lib/code.py
index 9020aab7016..f8184b6c22e 100644
--- a/Lib/code.py
+++ b/Lib/code.py
@@ -216,7 +216,7 @@ class InteractiveConsole(InteractiveInterpreter):
             self.write("Python %s on %s\n%s\n(%s)\n" %
                        (sys.version, sys.platform, cprt,
                         self.__class__.__name__))
-        else:
+        elif banner:
             self.write("%s\n" % str(banner))
         more = 0
         while 1:
diff --git a/Lib/test/test_code_module.py b/Lib/test/test_code_module.py
index adef1701d46..5fd21dc32c6 100644
--- a/Lib/test/test_code_module.py
+++ b/Lib/test/test_code_module.py
@@ -64,6 +64,20 @@ class TestInteractiveConsole(unittest.TestCase):
         self.console.interact()
         self.assertTrue(hook.called)
 
+    def test_banner(self):
+        # with banner
+        self.infunc.side_effect = EOFError('Finished')
+        self.console.interact(banner='Foo')
+        self.assertEqual(len(self.stderr.method_calls), 2)
+        banner_call = self.stderr.method_calls[0]
+        self.assertEqual(banner_call, ['write', ('Foo\n',), {}])
+
+        # no banner
+        self.stderr.reset_mock()
+        self.infunc.side_effect = EOFError('Finished')
+        self.console.interact(banner='')
+        self.assertEqual(len(self.stderr.method_calls), 1)
+
 
 def test_main():
     support.run_unittest(TestInteractiveConsole)