Add RTL support to python-docs-theme

python_docs_theme/__init__.py

@@ -2,6 +2,7 @@
 
 from pathlib import Path
 
+from markupsafe import Markup, escape
 from sphinx.locale import get_translation
 
 TYPE_CHECKING = False
@@ -18,6 +19,12 @@
 MESSAGE_CATALOG_NAME = "python-docs-theme"
 
 
+def _tobool(val: object) -> bool:
+    if isinstance(val, str):
+        return val.lower() in {"true", "1", "yes", "on"}
+    return bool(val)
+
+
 def add_translation_to_context(
     app: Sphinx,
     pagename: str,
@@ -37,12 +44,37 @@ def combined(message: str) -> str:
     context["_"] = context["gettext"] = context["ngettext"] = combined
 
 
+def add_html_dir_to_context(
+    app: Sphinx,
+    pagename: str,
+    templatename: str,
+    context: dict[str, Any],
+    doctree: None,
+) -> None:
+    language = app.config.language or "en"
+
+    is_rtl_option = context.get("theme_is_rtl", "")
+    if is_rtl_option in (None, ""):
+        is_rtl = False
+    else:
+        is_rtl = _tobool(is_rtl_option)
+
+    dir_attr = "rtl" if is_rtl else "ltr"
+
+    content_root = context.get("content_root", "")
+    lang_part = f' lang="{escape(language)}"' if language is not None else ""
+    context["html_tag"] = Markup(
+        f'<html{lang_part} dir="{dir_attr}" data-content_root="{escape(content_root)}">'
+    )
+
+
 def setup(app: Sphinx) -> ExtensionMetadata:
     app.require_sphinx("7.3")
 
     app.add_html_theme("python_docs_theme", str(THEME_PATH))
     app.add_message_catalog(MESSAGE_CATALOG_NAME, LOCALE_DIR)
     app.connect("html-page-context", add_translation_to_context)
+    app.connect("html-page-context", add_html_dir_to_context)
 
     return {
         "version": __version__,

python_docs_theme/layout.html

@@ -6,7 +6,7 @@
       <h3>{{ _('Navigation') }}</h3>
       <ul>
           {%- for rellink in rellinks %}
-          <li class="right" {% if loop.first %}style="margin-right: 10px"{% endif %}>
+          <li class="right" {% if loop.first %}style="margin-inline-end: 10px"{% endif %}>
               <a href="{{ pathto(rellink[0])|e }}" title="{{ rellink[1]|striptags|e }}"
                  {{ accesskey(rellink[2]) }}>{{ rellink[3] }}
               </a>