Close issue #8931: Make alternate formatting for 'c' raise an exception. Patch by Torsten Landschoff.
diff --git a/Lib/test/test_types.py b/Lib/test/test_types.py
index ec10752..11d9546 100644
--- a/Lib/test/test_types.py
+++ b/Lib/test/test_types.py
@@ -343,6 +343,8 @@
self.assertRaises(ValueError, 3 .__format__, ",n")
# can't have ',' with 'c'
self.assertRaises(ValueError, 3 .__format__, ",c")
+ # can't have '#' with 'c'
+ self.assertRaises(ValueError, 3 .__format__, "#c")
# ensure that only int and float type specifiers work
for format_spec in ([chr(x) for x in range(ord('a'), ord('z')+1)] +
diff --git a/Misc/NEWS b/Misc/NEWS
index 4da2333..6d4a6e4 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -43,6 +43,10 @@
replacement fields. It now matches the behavior of str.format() in
this regard. Patches by Phil Elson and Ramchandra Apte.
+- Issue #8931: Make alternate formatting ('#') for type 'c' raise an
+ exception. In versions prior to 3.5, '#' with 'c' had no effect. Now
+ specifying it is an error. Patch by Torsten Landschoff.
+
Library
-------
diff --git a/Python/formatter_unicode.c b/Python/formatter_unicode.c
index e3a8149..056bb76 100644
--- a/Python/formatter_unicode.c
+++ b/Python/formatter_unicode.c
@@ -846,6 +846,13 @@
" format specifier 'c'");
goto done;
}
+ /* error to request alternate format */
+ if (format->alternate) {
+ PyErr_SetString(PyExc_ValueError,
+ "Alternate form (#) not allowed with integer"
+ " format specifier 'c'");
+ goto done;
+ }
/* taken from unicodeobject.c formatchar() */
/* Integer input truncated to a character */