Tests: Fix deprecation warning with new sphinx versions (#1105)

* Tests: Fix deprecation warning with new sphinx versions

These builders where split in sphinx and the old import path will be removed in the upcoming Sphinx 4 release.

This patch requires sphinx 2 so this will be committed into the v2 release.

* Fix imports

* Use try/except for backwards compatibility

Author: Blendify

tests/test_builders.py

@@ -3,7 +3,15 @@
 import pytest
 import sphinx
 from sphinx import addnodes
-from sphinx.builders.html import SingleFileHTMLBuilder, DirectoryHTMLBuilder
+try:
+    # Available from Sphinx 2.0
+    from sphinx.builders.dirhtml import DirectoryHTMLBuilder
+    from sphinx.builders.singlehtml import SingleFileHTMLBuilder
+except ImportError:
+    from sphinx.builders.html import (
+        DirectoryHTMLBuilder,
+        SingleFileHTMLBuilder,
+    )
 
 from .util import build_all