#2543: Fix CI errors

src/psyclone/psyir/nodes/node.py

@@ -553,7 +553,7 @@ def dag(self, file_name='dag', file_format='svg'):
         self.dag_gen(graph)
         try:
             graph.render(filename=file_name)
-        except graphviz.backend.execute.ExecutableNotFound as error:
+        except graphviz.ExecutableNotFound as error:
             print(error)
             # TODO #11 add a warning to a log file here
             # silently return if graphviz bindings are not installed

src/psyclone/tests/conftest.py

@@ -81,10 +81,11 @@ def have_graphviz():
     ''' Whether or not the system has graphviz installed. Note that this
     only checks for the Python bindings. The underlying library must
     also have been installed for dag generation to work correctly. '''
+    # pylint: disable=import-outside-toplevel
+    import graphviz
     try:
-        # pylint: disable=import-outside-toplevel, unused-import
-        import graphviz  # noqa: F401
-    except ImportError:
+        graphviz.version()
+    except graphviz.ExecutableNotFound:
         return False
     return True
 

src/psyclone/tests/psyir/nodes/node_test.py

@@ -728,7 +728,7 @@ def test_node_dag_no_graphviz(tmpdir, monkeypatch):
     when graphviz is not installed. We make this test independent of whether or
     not graphviz is installed by monkeypatching sys.modules. '''
     def not_installed(_, **kwargs):
-        raise graphviz.backend.execute.ExecutableNotFound("error")
+        raise graphviz.ExecutableNotFound("error")
     monkeypatch.setattr(graphviz.graphs.Digraph, "render", not_installed)
     monkeypatch.setitem(sys.modules, 'graphviz', None)
     _, invoke_info = parse(