Unit Test for constraints

test/conftest.py

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+# -*- coding: utf-8 -*-
+import pandas as pd
+import pypsa
+import pytest
+
+
+@pytest.fixture
+def network():
+    n = pypsa.Network()
+    n.set_snapshots(pd.date_range("2022-01-01", periods=24, freq="H"))
+    n.add("Bus", "bus1")
+    n.add(
+        "Link",
+        "battery discharger",
+        bus0="bus1",
+        bus1="bus1",
+        p_nom_extendable=True,
+        efficiency=0.9,
+    )
+    n.add("Link", "battery charger", bus0="bus1", bus1="bus1", p_nom_extendable=True)
+
+    # Add links
+    n.add(
+        "Link",
+        "urban central CHP electric",
+        bus0="bus0",
+        bus1="bus1",
+        p_nom_extendable=True,
+        efficiency=0.9,
+        p_nom_ratio=1.0,
+    )
+    n.add(
+        "Link",
+        "urban central CHP heat",
+        bus0="bus1",
+        bus1="bus0",
+        p_nom_extendable=True,
+        efficiency=0.9,
+    )
+
+    n.optimize.create_model()
+
+    return n

test/test_solve_network_constraints.py

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+# -*- coding: utf-8 -*-
+import sys
+
+import pypsa
+import pytest
+
+sys.path.append("./scripts")
+from test.conftest import network
+
+import _helpers
+from solve_network import add_battery_constraints, add_chp_constraints
+
+
+def test_add_battery_constraints(network):
+
+    # Apply the function
+    add_battery_constraints(network)
+
+    constraints = network.model.constraints["Link-charger_ratio"]
+    assert constraints is not None
+
+    # Check that the constraints were added
+    assert "Link-charger_ratio" in network.model.constraints
+
+    # Check the constraint expression
+    lhs = network.model.constraints["Link-charger_ratio"][0].lhs
+
+    assert lhs.equals(
+        network.model["Link-p_nom"].loc["battery charger"]
+        - 0.9 * network.model["Link-p_nom"].loc["battery discharger"]
+    )
+
+
+def test_chp_constraints(network):
+
+    # Apply the function
+    add_chp_constraints(network)
+
+    constraints = network.model.constraints["Link-CHP_ratio"]
+    assert constraints is not None
+
+    # Check that the constraints were added
+    assert "Link-CHP_ratio" in network.model.constraints
+
+    # Check the constraint expression
+    lhs = network.model.constraints["Link-CHP_ratio"][0].lhs
+
+    assert lhs.equals(
+        network.model["Link-p_nom"].loc["urban central CHP heat"]
+        - 0.9 * network.model["Link-p_nom"].loc["urban central CHP electric"]
+    )