Revert upstream patch for compatibility with older sphinx

0001-Fix-build-with-sphinx-4.patch

@@ -0,0 +1,35 @@
+From 1fd2aef4fcaabddcb533ffe2f999e55d1e3ce7fe Mon Sep 17 00:00:00 2001
+From: Elliott Sales de Andrade <quantum.analyst@gmail.com>
+Date: Sun, 11 Jul 2021 17:54:54 -0400
+Subject: [PATCH] Fix build with Sphinx 4.
+
+`add_stylesheet` was deprecated in 1.8 and removed in 4.0 [1]. The
+replacement, `add_css_file` was added in 1.0, which is older than any
+version required by `breathe`.
+
+[1] https://www.sphinx-doc.org/en/master/extdev/deprecated.html?highlight=add_stylesheet
+---
+ docs/source/conf.py | 5 +++--
+ 1 file changed, 3 insertions(+), 2 deletions(-)
+
+diff --git a/docs/source/conf.py b/docs/source/conf.py
+index 333b75c..242e3fd 100644
+--- a/docs/source/conf.py
++++ b/docs/source/conf.py
+@@ -15,8 +15,10 @@
+ 
+ html_theme_path = [sphinx_rtd_theme.get_html_theme_path()]
+ 
++
+ def setup(app):
+-    app.add_stylesheet("main_stylesheet.css")
++    app.add_css_file("main_stylesheet.css")
++
+ 
+ extensions = ['breathe']
+ breathe_projects = { 'xtl': '../xml' }
+@@ -35,4 +37,3 @@ def setup(app):
+ pygments_style = 'sphinx'
+ todo_include_todos = False
+ htmlhelp_basename = 'xtldoc'
+-

xtl.spec

@@ -9,6 +9,8 @@ Summary:        QuantStack tools library
 Url:            https://github.com/QuantStack/xtl
 Source0:        https://github.com/QuantStack/%{name}/archive/%{version}/%{name}-%{version}.tar.gz
 
+Patch0:         0001-Fix-build-with-sphinx-4.patch
+
 BuildRequires:  binutils
 BuildRequires:  cmake
 BuildRequires:  doctest-devel
@@ -41,7 +43,11 @@ Documentation files for %{name} library.
 
 
 %prep
-%autosetup -p1
+%autosetup -p1 -N
+
+%if 0%{?rhel} && 0%{?rhel} < 9
+%patch -P0 -p1 -R
+%endif
 
 
 %build
@@ -59,7 +65,7 @@ popd
 
 
 %check
-make -C "%{_vpath_builddir}" xtest
+make -C "%{__cmake_builddir}" xtest
 
 
 %files devel