GH-109209: Bump the minimum Sphinx version to 4.2

.github/workflows/reusable-docs.yml

@@ -74,7 +74,7 @@ jobs:
     - name: 'Set up Python'
       uses: actions/setup-python@v4
       with:
-        python-version: '3.11'  # known to work with Sphinx 3.2
+        python-version: '3.11'  # known to work with Sphinx 4.2
         cache: 'pip'
         cache-dependency-path: 'Doc/requirements-oldest-sphinx.txt'
     - name: 'Install build dependencies'

Doc/conf.py

@@ -66,7 +66,7 @@
 highlight_language = 'python3'
 
 # Minimum version of sphinx required
-needs_sphinx = '3.2'
+needs_sphinx = '4.2'
 
 # Ignore any .rst files in the includes/ directory;
 # they're embedded in pages but not rendered individually.

Doc/requirements-oldest-sphinx.txt

@@ -7,12 +7,10 @@ blurb
 python-docs-theme>=2022.1
 
 # Generated from:
-#     pip install "Sphinx~=3.2.0" "docutils<0.17" "Jinja2<3" "MarkupSafe<2"
+#     pip install "Sphinx~=4.2.0"
 #     pip freeze
 #
-# Sphinx 3.2 comes from ``needs_sphinx = '3.2'`` in ``Doc/conf.py``.
-# Docutils<0.17, Jinja2<3, and MarkupSafe<2 are additionally specified as
-# Sphinx 3.2 is incompatible with newer releases of these packages.
+# Sphinx 4.2 comes from ``needs_sphinx = '4.2'`` in ``Doc/conf.py``.
 
 alabaster==0.7.13
 Babel==2.12.1
@@ -25,10 +23,10 @@ imagesize==1.4.1
 Jinja2==2.11.3
 MarkupSafe==1.1.1
 packaging==23.1
-Pygments==2.15.1
+Pygments==2.16.1
 requests==2.31.0
 snowballstemmer==2.2.0
-Sphinx==3.2.1
+Sphinx==4.2.0
 sphinxcontrib-applehelp==1.0.4
 sphinxcontrib-devhelp==1.0.2
 sphinxcontrib-htmlhelp==2.0.1

Misc/NEWS.d/next/Documentation/2023-09-10-02-39-06.gh-issue-109209.0LBewo.rst

@@ -0,0 +1 @@
+The minimum Sphinx version required for the documentation is now 4.2.