BUG: passing parameters for graph construction

dagrunner/execute_graph.py

@@ -245,7 +245,7 @@ def __init__(
           Optional global keyword arguments to apply to all applicable plugins.
         """
         self._nxgraph = _get_networkx(networkx_graph)
-        self._nxgraph_kwargs = networkx_graph_kwargs
+        self._nxgraph_kwargs = networkx_graph_kwargs or {}
         self._plugin_executor = plugin_executor
         if scheduler not in SCHEDULERS:
             raise ValueError(
@@ -278,7 +278,7 @@ def _process_graph(self):
         )
 
         if callable(self._nxgraph):
-            self._nxgraph = self._nxgraph(self._nxgraph_kwargs)
+            self._nxgraph = self._nxgraph(**self._nxgraph_kwargs)
 
         exec_graph = {}
         for node_id, properties in self._nxgraph.nodes(data=True):

dagrunner/tests/execute_graph/test_ExecuteGraph.py

@@ -0,0 +1,43 @@
+# (C) Crown Copyright, Met Office. All rights reserved.
+#
+# This file is part of 'dagrunner' and is released under the BSD 3-Clause license.
+# See LICENSE in the root of the repository for full licensing details.
+import networkx as nx
+
+from dagrunner.execute_graph import ExecuteGraph
+
+
+def test___init___graph_non_callable():
+    """Passing a non-callable graph to ExecuteGraph."""
+    dummy_digraph = nx.DiGraph()
+    exe_graph = ExecuteGraph(dummy_digraph)
+    assert exe_graph.nxgraph is dummy_digraph
+
+
+def test___init___graph_callable_no_parameters():
+    """Passing a callable graph to ExecuteGraph with no parameters."""
+    dummy_digraph = nx.DiGraph()
+    exe_graph = ExecuteGraph(lambda: dummy_digraph)
+    assert exe_graph.nxgraph is dummy_digraph
+
+
+def setup_graph_gen_callable(graph):
+    def gen_graph(param_a, param_b):
+        graph.add_nodes_from([param_a, param_b])
+        return graph
+
+    return gen_graph
+
+
+def test___init___graph_callable_with_parameters():
+    """Passing a callable graph to ExecuteGraph with parameters."""
+    dummy_digraph = nx.DiGraph()
+    graph_gen = setup_graph_gen_callable(dummy_digraph)
+    exe_graph = ExecuteGraph(
+        graph_gen, networkx_graph_kwargs={"param_a": "val_a", "param_b": "val_b"}
+    )
+
+    target_graph = nx.DiGraph()
+    target_graph.add_nodes_from(["val_a", "val_b"])
+    assert exe_graph.nxgraph is dummy_digraph
+    assert dummy_digraph.nodes == target_graph.nodes