Issue #7094: Add alternate ('#') flag to __format__ methods for float, complex and Decimal. Allows greater control over when decimal points appear. Added to make transitioning from %-formatting easier. '#g' still has a problem with Decimal which I'll fix soon.
diff --git a/Lib/decimal.py b/Lib/decimal.py
index 5a9f840..f379ee5 100644
--- a/Lib/decimal.py
+++ b/Lib/decimal.py
@@ -5991,7 +5991,7 @@
#
# A format specifier for Decimal looks like:
#
-# [[fill]align][sign][0][minimumwidth][,][.precision][type]
+# [[fill]align][sign][#][0][minimumwidth][,][.precision][type]
_parse_format_specifier_regex = re.compile(r"""\A
(?:
@@ -5999,6 +5999,7 @@
(?P<align>[<>=^])
)?
(?P<sign>[-+ ])?
+(?P<alt>\#)?
(?P<zeropad>0)?
(?P<minimumwidth>(?!0)\d+)?
(?P<thousands_sep>,)?
@@ -6214,7 +6215,7 @@
sign = _format_sign(is_negative, spec)
- if fracpart:
+ if fracpart or spec['alt']:
fracpart = spec['decimal_point'] + fracpart
if exp != 0 or spec['type'] in 'eE':