feat: add reusable workflow definition graphs

tests/test_manifest.py

@@ -0,0 +1,32 @@
+from __future__ import annotations
+
+import unittest
+
+from govoplan_workflow.backend.manifest import (
+    DEFINITION_READ_SCOPE,
+    DEFINITION_WRITE_SCOPE,
+    get_manifest,
+)
+
+
+class WorkflowManifestTests(unittest.TestCase):
+    def test_manifest_exposes_definition_contracts(self) -> None:
+        manifest = get_manifest()
+
+        self.assertEqual(manifest.id, "workflow")
+        self.assertIn(
+            "workflow.definition_graph",
+            {item.name for item in manifest.provides_interfaces},
+        )
+        self.assertIn(
+            DEFINITION_READ_SCOPE,
+            {item.scope for item in manifest.permissions},
+        )
+        self.assertIn(
+            DEFINITION_WRITE_SCOPE,
+            {item.scope for item in manifest.permissions},
+        )
+
+
+if __name__ == "__main__":
+    unittest.main()

tests/test_node_library.py

@@ -0,0 +1,97 @@
+from __future__ import annotations
+
+import unittest
+
+from govoplan_workflow.backend.node_library import WORKFLOW_GRAPH_LIBRARY
+from govoplan_workflow.backend.schemas import WorkflowEdge, WorkflowGraph, WorkflowNode
+from govoplan_workflow.backend.validation import validate_workflow_graph
+
+
+class WorkflowNodeLibraryTests(unittest.TestCase):
+    def test_valid_workflow_graph(self) -> None:
+        graph = WorkflowGraph(
+            nodes=[
+                WorkflowNode(id="start", type="workflow.start.manual"),
+                WorkflowNode(
+                    id="work",
+                    type="workflow.activity",
+                    config={"title": "Check submission"},
+                ),
+                WorkflowNode(id="done", type="workflow.end.completed"),
+            ],
+            edges=[
+                WorkflowEdge(id="e1", source="start", target="work"),
+                WorkflowEdge(id="e2", source="work", target="done"),
+            ],
+        )
+
+        self.assertEqual(validate_workflow_graph(graph), ())
+
+    def test_correction_loop_is_allowed(self) -> None:
+        graph = WorkflowGraph(
+            nodes=[
+                WorkflowNode(id="start", type="workflow.start.manual"),
+                WorkflowNode(
+                    id="work",
+                    type="workflow.activity",
+                    config={"title": "Prepare"},
+                ),
+                WorkflowNode(
+                    id="review",
+                    type="workflow.review",
+                    config={"title": "Review"},
+                ),
+                WorkflowNode(id="done", type="workflow.end.completed"),
+            ],
+            edges=[
+                WorkflowEdge(id="e1", source="start", target="work"),
+                WorkflowEdge(id="e2", source="work", target="review"),
+                WorkflowEdge(
+                    id="e3",
+                    source="review",
+                    source_port="changes",
+                    target="work",
+                ),
+                WorkflowEdge(
+                    id="e4",
+                    source="review",
+                    source_port="approved",
+                    target="done",
+                ),
+            ],
+        )
+
+        self.assertNotIn(
+            "graph.cycle",
+            {item.code for item in validate_workflow_graph(graph)},
+        )
+
+    def test_constraints_and_required_configuration_are_reported(self) -> None:
+        graph = WorkflowGraph(
+            nodes=[
+                WorkflowNode(id="start-1", type="workflow.start.manual"),
+                WorkflowNode(
+                    id="start-2",
+                    type="workflow.start.event",
+                    config={"event_type": ""},
+                ),
+            ],
+            edges=[
+                WorkflowEdge(id="e1", source="start-1", target="start-2"),
+            ],
+        )
+
+        diagnostics = validate_workflow_graph(graph)
+        codes = {item.code for item in diagnostics}
+        self.assertIn("graph.trigger_count", codes)
+        self.assertIn("graph.outcome_count", codes)
+        self.assertIn("node.config_required", codes)
+        self.assertIn("node.outgoing_required", codes)
+
+    def test_library_has_domain_specific_cycle_policy(self) -> None:
+        self.assertTrue(WORKFLOW_GRAPH_LIBRARY.constraints.allow_cycles)
+        self.assertEqual(WORKFLOW_GRAPH_LIBRARY.id, "workflow")
+
+
+if __name__ == "__main__":
+    unittest.main()