Issue #8048: Prevent doctests from failing when sys.displayhook has
been reassigned.
diff --git a/Lib/test/test_doctest.py b/Lib/test/test_doctest.py
index 873e495..b6eeaed 100644
--- a/Lib/test/test_doctest.py
+++ b/Lib/test/test_doctest.py
@@ -980,6 +980,35 @@
ZeroDivisionError: integer division or modulo by zero
TestResults(failed=1, attempted=1)
"""
+ def displayhook(): r"""
+Test that changing sys.displayhook doesn't matter for doctest.
+
+ >>> import sys
+ >>> orig_displayhook = sys.displayhook
+ >>> def my_displayhook(x):
+ ... print('hi!')
+ >>> sys.displayhook = my_displayhook
+ >>> def f():
+ ... '''
+ ... >>> 3
+ ... 3
+ ... '''
+ >>> test = doctest.DocTestFinder().find(f)[0]
+ >>> r = doctest.DocTestRunner(verbose=False).run(test)
+ >>> post_displayhook = sys.displayhook
+
+ We need to restore sys.displayhook now, so that we'll be able to test
+ results.
+
+ >>> sys.displayhook = orig_displayhook
+
+ Ok, now we can check that everything is ok.
+
+ >>> r
+ TestResults(failed=0, attempted=1)
+ >>> post_displayhook is my_displayhook
+ True
+"""
def optionflags(): r"""
Tests of `DocTestRunner`'s option flag handling.