docs: generate changelog

.gitignore

@@ -6,5 +6,5 @@
 /_build
 /dist
 /docs/_build
-CHANGELOG.md
+CHANGELOG.*
 __pycache__

.readthedocs.yaml

@@ -6,6 +6,7 @@ build:
     python: "3.9"
   jobs:
     post_checkout:
+      - git fetch --unshallow || true
       - >
         git_lfs_ver="3.3.0";
         wget -qO- https://github.com/git-lfs/git-lfs/releases/download/v${git_lfs_ver}/git-lfs-linux-amd64-v${git_lfs_ver}.tar.gz

docs/changelog.rst

@@ -0,0 +1,5 @@
+=========
+Changelog
+=========
+
+.. osr:cz-changelog::

docs/index.rst

@@ -117,5 +117,6 @@ Specifications
     console
     related-projects
     about
+    changelog
     copyright
     indices

src/osr_sphinx/commitizen.py

@@ -0,0 +1,50 @@
+"""Commitizen Sphinx directives."""
+
+from __future__ import annotations
+
+import subprocess
+
+from docutils import nodes
+from docutils.frontend import OptionParser
+from docutils.utils import new_document
+from sphinx.parsers import RSTParser
+from sphinx.util.docutils import SphinxDirective
+
+
+class CzChangelog(SphinxDirective):
+    """Commitizen changelog directive."""
+
+    has_content = False
+    required_arguments = 0
+    optional_arguments = 0
+
+    def run(self) -> list[nodes.Node]:
+        """Run Commitizen changelog."""
+        changelog = self.get_changelog()
+
+        return self.parse_rst(changelog)
+
+    @staticmethod
+    def get_changelog() -> str:
+        """Execute cz changelog and capture output."""
+        result = subprocess.run(
+            ["cz", "changelog", "--dry-run", "--file-name", "CHANGELOG.rst"],
+            stdout=subprocess.PIPE,
+        )
+
+        return result.stdout.decode("utf-8")
+
+    def parse_rst(self, text: str) -> list[nodes.Node]:
+        """Parse reStructuredText string."""
+        parser = RSTParser()
+        parser.set_application(self.env.app)
+        settings = OptionParser(
+            defaults=self.env.settings,
+            components=(RSTParser,),
+            read_config_files=True,
+        ).get_default_values()
+
+        document = new_document("<rst-doc>", settings=settings)
+        parser.parse(text, document)
+
+        return document.children

src/osr_sphinx/domain.py

@@ -11,6 +11,7 @@
 from sphinx.environment import BuildEnvironment
 
 from osr_sphinx.bom import BomTable
+from osr_sphinx.commitizen import CzChangelog
 from osr_sphinx.dimensions import DimensionRole
 from osr_sphinx.print_settings import PrintSettings
 
@@ -23,6 +24,7 @@ class OsrDomain(Domain):
 
     directives = {
         "bom": BomTable,
+        "cz-changelog": CzChangelog,
         "print-settings": PrintSettings,
     }
     roles = {