version: Support :break: option

Author: SilverRainZ

src/sphinxnotes/project/anyobjtypes.py

@@ -41,7 +41,8 @@ def _read_template_file(name: str) -> str:
     'version': {
         'schema': {
             'attrs': {
-                'date': 'date, required, ref, index by year',
+                'date': 'date, ref, index by year',
+                'break': 'flag',
             },
         },
         'templates': {

src/sphinxnotes/project/templates/version.rst

@@ -1,11 +1,14 @@
-
+{% if date -%}
 :Date: :version.date+by-year:`📅{{ date }} <{{ date }}>`
 :Download: :tag:`{{ name }}`
-
-{% if not date -%}
+{% else -%}
 .. note:: This version is still under development and has not been released yet.
 {%- endif%}
 
+{% if break -%}
+.. warning:: **This version contains INCOMPATIBLE changes.**
+{%- endif%}
+
 {% for line in content.split('\n') -%}
 {{ line }}
 {% endfor %}