Add ABC FlowInterface tests

tests/test_FlowInterface.py

@@ -0,0 +1,38 @@
+# ===================================================
+#
+#    Copyright (c) 2023-2024
+#      SPARKX Team
+#
+#    GNU General Public License (GPLv3 or later)
+#
+# ===================================================
+
+from sparkx.flow.FlowInterface import FlowInterface
+
+
+class DummyFlow(FlowInterface):
+    def __init__(self, *args, **kwargs):
+        self.args = args
+        self.kwargs = kwargs
+
+    def integrated_flow(self, particle_data, *args, **kwargs):
+        return "integrated_flow called"
+
+    def differential_flow(
+        self, particle_data, bins, flow_as_function_of, *args, **kwargs
+    ):
+        return "differential_flow called"
+
+
+def test_integrated_flow():
+    flow = DummyFlow()
+    result = flow.integrated_flow("particle_data")
+    assert result == "integrated_flow called"
+
+
+def test_differential_flow():
+    flow = DummyFlow()
+    result = flow.differential_flow(
+        "particle_data", "bins", "flow_as_function_of"
+    )
+    assert result == "differential_flow called"