really drop python<=3.8 support

src/sphinx_book_theme/__init__.py

@@ -139,10 +139,8 @@ def update_mode_thebe_config(app):
         # but has not activated the sphinx_thebe extension.
         if not hasattr(app.env.config, "thebe_config"):
             SPHINX_LOGGER.warning(
-                (
-                    "Thebe is activated but not added to extensions list. "
-                    "Add `sphinx_thebe` to your site's extensions list."
-                )
+                "Thebe is activated but not added to extensions list. "
+                "Add `sphinx_thebe` to your site's extensions list."
             )
             return
         # Will be empty if it doesn't exist

src/sphinx_book_theme/_compat.py

@@ -1,5 +1,5 @@
 from docutils.nodes import Element
-from typing import Iterator
+from collections.abc import Iterator
 
 
 def findall(node: Element, *args, **kwargs) -> Iterator[Element]:

src/sphinx_book_theme/header_buttons/__init__.py

@@ -173,10 +173,8 @@ def update_context_with_repository_info(app):
     # If provider is still empty, raise an error because we don't recognize it
     if provider == "":
         raise SphinxError(
-            (
-                f"Provider not recognized in repository url {repo_url}. "
-                "If you're using a custom provider URL, specify `repository_provider`"
-            )
+            f"Provider not recognized in repository url {repo_url}. "
+            "If you're using a custom provider URL, specify `repository_provider`"
         )
 
     # Update the context because this is what the get_edit_url function uses.

src/sphinx_book_theme/header_buttons/launch.py

@@ -1,7 +1,7 @@
 """Launch buttons for Binder / Thebe / Colab / etc."""
 
 from pathlib import Path
-from typing import Any, Dict, Optional
+from typing import Any, Optional
 from urllib.parse import urlencode, quote
 
 from docutils.nodes import document
@@ -23,7 +23,7 @@ def add_launch_buttons(
     app: Sphinx,
     pagename: str,
     templatename: str,
-    context: Dict[str, Any],
+    context: dict[str, Any],
     doctree: Optional[document],
 ):
     """Builds a binder link and inserts it in HTML context for use in templating.
@@ -89,11 +89,9 @@ def add_launch_buttons(
     notebook_interface = launch_buttons.get("notebook_interface", "classic")
     if notebook_interface not in notebook_interface_prefixes:
         raise ValueError(
-            (
-                "Notebook UI for Binder/JupyterHub links must be one"
-                f"of {tuple(notebook_interface_prefixes.keys())},"
-                f"not {notebook_interface}"
-            )
+            "Notebook UI for Binder/JupyterHub links must be one"
+            f"of {tuple(notebook_interface_prefixes.keys())},"
+            f"not {notebook_interface}"
         )
     ui_pre = notebook_interface_prefixes[notebook_interface]
 

tests/test_build.py

@@ -86,7 +86,7 @@ def test_build_book(sphinx_build_factory, file_regression):
     for filename, kernel in kernels_expected.items():
         ntbk_html = sphinx_build.html_tree("section1", filename)
         thebe_config = ntbk_html.find("script", attrs={"type": "text/x-thebe-config"})
-        kernel_name = 'name: "{}",'.format(kernel)
+        kernel_name = f'name: "{kernel}",'
         if kernel_name not in thebe_config.prettify():
             raise AssertionError(f"{kernel_name} not in {kernels_expected}")