Fixed options according to official documentation.

See sphinx-doc/sphinx#6991 (comment)

README.md

@@ -23,9 +23,10 @@ This is a patched version of [`sphinx.ext.graphviz`](https://github.com/sphinx-d
 
 --------------------
 
-## Added features
+## Added features and changes
 
-* TBD
+* `2.3.1.post1`
+  * Updated directive options according to documentation (see: [sphinx-doc/sphinx#6991](https://github.com/sphinx-doc/sphinx/issues/6991#issuecomment-573446371))
 
 ## Cross-References
 

btd/sphinx/graphviz.py

@@ -151,9 +151,9 @@ def run(self) -> List[Node]:
         node['options'] = {'docname': self.env.docname}
 
         if 'graphviz_dot' in self.options:
-            node['options']['graphviz_dot'] = self.options['graphviz_dot']
+            node['options']['layout'] = self.options['graphviz_dot']
         if 'layout' in self.options:
-            node['options']['graphviz_dot'] = self.options['layout']
+            node['options']['layout'] = self.options['layout']
         if 'alt' in self.options:
             node['alt'] = self.options['alt']
         if 'align' in self.options:
@@ -180,7 +180,8 @@ class GraphvizSimple(SphinxDirective):
         'alt': directives.unchanged,
         'align': align_spec,
         'caption': directives.unchanged,
-        'graphviz_dot': directives.unchanged,
+        'layout': directives.unchanged,
+        'graphviz_dot': directives.unchanged,  # an old alias of `layout` option
         'name': directives.unchanged,
     }
 
@@ -190,7 +191,9 @@ def run(self) -> List[Node]:
                        (self.name, self.arguments[0], '\n'.join(self.content))
         node['options'] = {'docname': self.env.docname}
         if 'graphviz_dot' in self.options:
-            node['options']['graphviz_dot'] = self.options['graphviz_dot']
+            node['options']['layout'] = self.options['graphviz_dot']
+        if 'layout' in self.options:
+            node['options']['layout'] = self.options['layout']
         if 'alt' in self.options:
             node['alt'] = self.options['alt']
         if 'align' in self.options:
@@ -208,7 +211,7 @@ def run(self) -> List[Node]:
 def render_dot(self: SphinxTranslator, code: str, options: Dict,
                format: str, prefix: str = 'graphviz') -> Tuple[str, str]:
     """Render graphviz code into a PNG or PDF output file."""
-    graphviz_dot = options.get('graphviz_dot', self.builder.config.graphviz_dot)
+    graphviz_dot = options.get('layout', self.builder.config.graphviz_dot)
     hashkey = (code + str(options) + str(graphviz_dot) +
                str(self.builder.config.graphviz_dot_args)).encode()
 

setup.py

@@ -49,7 +49,7 @@
 
 projectName =           "sphinx.graphviz"
 projectNameWithPrefix = "btd." + projectName
-version =               "2.3.1.post1.dev1"
+version =               "2.3.1.post1"
 
 github_url =  "https://github.com/buildthedocs/" + projectName
 rtd_url =     "https://" + projectNameWithPrefix.replace(".", "-") + ".readthedocs.io/en/latest/"