Note behavior change of RenderSVG._make_id to SHA512 #18192

daytonb · daytonb · commit bf4b626a02e4 · 2020-08-06T21:43:42.000-04:00
diff --git a/doc/api/next_api_changes/behavior/18193-BKB.rst b/doc/api/next_api_changes/behavior/18193-BKB.rst
@@ -0,0 +1,11 @@
+ID attribute of XML tags in SVG files now based on SHA512 rather than MD5
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The `RenderSVG._make_id` method generates unique ID attributes for various
+XML tags in SVG files. This method previously used the first 10 characters of
+an MD5 hash. The `hashlib.md5` constructor is not available in Python on
+systems with Federal Information Processing Standards (FIPS) enabled.
+`RenderSVG._make_id` now uses the first 10 characters of an SHA512 hash. The
+general behavior of this method remains unchanged, though SVG files that
+would otherwise those saved with earlier versions of matplotlib, will have
+different ID attributes.
