py/mpz: Skip separators when running out of digits to print.

This commit fixes the addition of a stray separator before the number
when printing an MPZ-backed integer and the first group is three digits
long.

This fixes #8984.

Signed-off-by: Alessandro Gatti <a.gatti@frob.it>

1 files changed, 15 insertions, 0 deletions

diff --git a/tests/basics/string_format_intbig.py b/tests/basics/string_format_intbig.py
new file mode 100644
index 000000000..a36c36752
--- /dev/null
+++ b/tests/basics/string_format_intbig.py
@@ -0,0 +1,15 @@
+# basic functionality test for {} format string using large integers
+
+
+def test(fmt, *args):
+    print("{:8s}".format(fmt) + ">" + fmt.format(*args) + "<")
+
+
+# Separator formatter
+
+test("{:,}", 123_456_789_012_345_678_901_234_567)
+test("{:,}", 23_456_789_012_345_678_901_234_567)
+test("{:,}", 3_456_789_012_345_678_901_234_567)
+test("{:,}", -123_456_789_012_345_678_901_234_567)
+test("{:,}", -23_456_789_012_345_678_901_234_567)
+test("{:,}", -3_456_789_012_345_678_901_234_567)