Fix for the case no min. and only max. repetition

We mistakenly omitted to mark a maximum repetition without an exactly
specified minimum, and represented it as an exact repetition.

The bug was revealed on tests with BCP47.

abnf_to_regexp/nested_python.py

@@ -314,7 +314,7 @@ def visit_repetition(self, element: Repetition) -> None:
             and element.max_occurrences is not None
             and element.max_occurrences > 0
         ):
-            suffix = f"{{{element.max_occurrences}}}"
+            suffix = f"{{,{element.max_occurrences}}}"
         elif (
             element.min_occurrences is not None
             and element.min_occurrences > 0

test_data/nested-python/bcp47/expected.py

@@ -1,7 +1,7 @@
 alphanum = '[a-zA-Z0-9]'
 singleton = '[0-9A-WY-Za-wy-z]'
 extension = f'{singleton}(-({alphanum}){{2,8}})+'
-extlang = '[a-zA-Z]{3}(-[a-zA-Z]{3}){2}'
+extlang = '[a-zA-Z]{3}(-[a-zA-Z]{3}){,2}'
 irregular = (
     '(en-GB-oed|i-ami|i-bnn|i-default|i-enochian|i-hak|'
     'i-klingon|i-lux|i-mingo|i-navajo|i-pwn|i-tao|i-tay|'

test_data/nested-python/rfc3986/expected.py

@@ -9,9 +9,10 @@
 ls32 = f'({h16}:{h16}|{ipv4address})'
 ipv6address = (
     f'(({h16}:){{6}}{ls32}|::({h16}:){{5}}{ls32}|({h16})?::({h16}:){{4}}'
-    f'{ls32}|(({h16}:)?{h16})?::({h16}:){{3}}{ls32}|(({h16}:){{2}}{h16})?::'
-    f'({h16}:){{2}}{ls32}|(({h16}:){{3}}{h16})?::{h16}:{ls32}|(({h16}:){{4}}'
-    f'{h16})?::{ls32}|(({h16}:){{5}}{h16})?::{h16}|(({h16}:){{6}}{h16})?::)'
+    f'{ls32}|(({h16}:)?{h16})?::({h16}:){{3}}{ls32}|(({h16}:){{,2}}{h16})?::'
+    f'({h16}:){{2}}{ls32}|(({h16}:){{,3}}{h16})?::{h16}:{ls32}|(({h16}:){{,4}}'
+    f'{h16})?::{ls32}|(({h16}:){{,5}}{h16})?::{h16}|(({h16}:){{,6}}{h16})?'
+    '::)'
 )
 ipvfuture = f'[vV][0-9A-Fa-f]+\\.({unreserved}|{sub_delims}|:)+'
 ip_literal = f'\\[({ipv6address}|{ipvfuture})\\]'

test_data/nested-python/rfc3987/expected.py

@@ -19,9 +19,10 @@
 ls32 = f'({h16}:{h16}|{ipv4address})'
 ipv6address = (
     f'(({h16}:){{6}}{ls32}|::({h16}:){{5}}{ls32}|({h16})?::({h16}:){{4}}'
-    f'{ls32}|(({h16}:)?{h16})?::({h16}:){{3}}{ls32}|(({h16}:){{2}}{h16})?::'
-    f'({h16}:){{2}}{ls32}|(({h16}:){{3}}{h16})?::{h16}:{ls32}|(({h16}:){{4}}'
-    f'{h16})?::{ls32}|(({h16}:){{5}}{h16})?::{h16}|(({h16}:){{6}}{h16})?::)'
+    f'{ls32}|(({h16}:)?{h16})?::({h16}:){{3}}{ls32}|(({h16}:){{,2}}{h16})?::'
+    f'({h16}:){{2}}{ls32}|(({h16}:){{,3}}{h16})?::{h16}:{ls32}|(({h16}:){{,4}}'
+    f'{h16})?::{ls32}|(({h16}:){{,5}}{h16})?::{h16}|(({h16}:){{,6}}{h16})?'
+    '::)'
 )
 unreserved = '[a-zA-Z0-9\\-._~]'
 ipvfuture = f'[vV][0-9A-Fa-f]+\\.({unreserved}|{sub_delims}|:)+'

test_data/nested-python/rfc8089/expected.py

@@ -4,9 +4,10 @@
 ls32 = f'({h16}:{h16}|{ipv4address})'
 ipv6address = (
     f'(({h16}:){{6}}{ls32}|::({h16}:){{5}}{ls32}|({h16})?::({h16}:){{4}}'
-    f'{ls32}|(({h16}:)?{h16})?::({h16}:){{3}}{ls32}|(({h16}:){{2}}{h16})?::'
-    f'({h16}:){{2}}{ls32}|(({h16}:){{3}}{h16})?::{h16}:{ls32}|(({h16}:){{4}}'
-    f'{h16})?::{ls32}|(({h16}:){{5}}{h16})?::{h16}|(({h16}:){{6}}{h16})?::)'
+    f'{ls32}|(({h16}:)?{h16})?::({h16}:){{3}}{ls32}|(({h16}:){{,2}}{h16})?::'
+    f'({h16}:){{2}}{ls32}|(({h16}:){{,3}}{h16})?::{h16}:{ls32}|(({h16}:){{,4}}'
+    f'{h16})?::{ls32}|(({h16}:){{,5}}{h16})?::{h16}|(({h16}:){{,6}}{h16})?'
+    '::)'
 )
 unreserved = '[a-zA-Z0-9\\-._~]'
 sub_delims = "[!$&'()*+,;=]"