fix: use loaded json instead of Path for extra configs

In order to be used by API.

Co-authored-by: Renato Ambrosone <renato.ambrosone@polito.it>

Signed-off-by: EstherLerouzic <esther.lerouzic@orange.com>
Change-Id: I12111427c8a90b85b3158cdd95f4ee771cb39316

tests/test_json_io.py

@@ -0,0 +1,56 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+
+# SPDX-License-Identifier: BSD-3-Clause
+# test_gain_mode
+# Copyright (C) 2025 Telecom Infra Project and GNPy contributors
+# see AUTHORS.rst for a list of contributors
+
+"""
+checks behaviour of gain mode
+- if all amps have their gains set, check that these gains are used, even if power_dbm or req_power change
+- check that saturation is correct in gain mode
+
+"""
+
+from pathlib import Path
+
+from gnpy.tools.json_io import  load_json, load_eqpt_topo_from_json
+import networkx as nx
+
+
+TEST_DIR = Path(__file__).parent
+DATA_DIR = TEST_DIR / 'data'
+EQPT_FILENAME = DATA_DIR / 'eqpt_config.json'
+NETWORK_FILENAME  = DATA_DIR / 'LinkforTest.json'
+EXTRA_CONFIGS = {"std_medium_gain_advanced_config.json": load_json(DATA_DIR / "std_medium_gain_advanced_config.json")}
+
+
+def test_load_eqpt_topo_from_json():
+    eqpt = load_json(EQPT_FILENAME)
+    topology = load_json(NETWORK_FILENAME)
+    extra_equipments = None
+    extra_configs = EXTRA_CONFIGS
+
+    equipment, network = load_eqpt_topo_from_json(eqpt, topology, extra_equipments, extra_configs)
+
+    assert isinstance(equipment, dict)
+    assert isinstance(network, nx.DiGraph)
+
+    assert len(network.nodes) > 0
+    assert len(network.edges) > 0
+
+
+def test_load_eqpt_topo_from_json_default_extra():
+    eqpt = load_json(EQPT_FILENAME)
+    topology = load_json(NETWORK_FILENAME)
+
+    equipment, network = load_eqpt_topo_from_json(eqpt, topology)
+
+    assert isinstance(equipment, dict)
+    assert isinstance(network, nx.DiGraph)
+    # Check that some expected nodes exist (example: 'A', 'B')
+    assert len(network.nodes) > 0
+    assert len(network.edges) > 0
+
+