Add test_MOM6InputParser.py to fully cover the tests

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Update dependency - pytest-mock

pyproject.toml

@@ -37,6 +37,7 @@ devel = [
 test = [
     "pytest",
     "pytest-cov",
+    "pytest-mock",
 ]
 
 [tool.pytest.ini_options]

tests/test_MOM6InputParser.py

@@ -0,0 +1,89 @@
+import pytest
+
+# from test_utils import MockFile
+from om3utils.MOM6InputParser import MOM6InputParser
+from unittest.mock import mock_open, call
+
+
+@pytest.fixture()
+def mom6_input():
+    return [
+        "! === HEADER 1 ===\n",
+        "REGRIDDING_COORDINATE_MODE = ZSTAR   ! default = 'LAYER''\n",
+        "                                     ! Coordinate mode for vertical regridding. Choose among the following\n",
+        "! === HEADER 2 ===\n",
+        "KPP%\n",
+        "N_SMOOTH = 4                         ! default = 0\n",
+        "                                     ! The number of times the 1-1-4-1-1 Laplacian filter is applied on OBL depth.\n",
+        "%KPP\n",
+        "DT = 1800.0\n",
+        "BOOL = True\n",
+    ]
+
+
+@pytest.fixture()
+def param_output():
+    return {
+        "REGRIDDING_COORDINATE_MODE": "ZSTAR",
+        "KPP%": "",
+        "N_SMOOTH": "4",
+        "%KPP": "",
+        "DT": "1800.0",
+        "BOOL": "True",
+    }
+
+
+@pytest.fixture()
+def commt_output():
+    return {
+        "REGRIDDING_COORDINATE_MODE": "default = 'LAYER''\n! Coordinate mode for vertical regridding. Choose among the following",
+        "KPP%": "",
+        "N_SMOOTH": "default = 0\n! The number of times the 1-1-4-1-1 Laplacian filter is applied on OBL depth.",
+        "%KPP": "",
+        "DT": "",
+        "BOOL": "",
+    }
+
+
+def test_read_mom6_input(mocker, mom6_input):
+    mocker.patch("builtins.open", mocker.mock_open(read_data="".join(mom6_input)))
+    parser = MOM6InputParser()
+    parser.read_input("tmp_path")
+    assert parser.lines == mom6_input
+
+
+def test_param_commt_output(mom6_input, param_output, commt_output):
+    parser = MOM6InputParser()
+    parser.lines = mom6_input
+    parser.parse_lines()
+    assert parser.param_dict == param_output
+    assert parser.commt_dict == commt_output
+
+
+def test_write_mom6_input(mocker, mom6_input):
+    mock_file = mock_open()
+    mocker.patch("builtins.open", mock_file)
+    parser = MOM6InputParser()
+    parser.lines = mom6_input
+    parser.parse_lines()
+    parser.writefile_MOM_input("tmp_path")  # write to the mock_file
+
+    expected_calls = [
+        call("! This file was written by the script xxx \n"),
+        call("! and records the non-default parameters used at run-time.\n"),
+        call("\n"),
+        call("REGRIDDING_COORDINATE_MODE = ZSTAR ! default = 'LAYER''\n"),
+        call(
+            "                                 ! Coordinate mode for vertical regridding. Choose among the following\n"
+        ),
+        call("KPP%\n"),
+        call("N_SMOOTH = 4                     ! default = 0\n"),
+        call(
+            "                                 ! The number of times the 1-1-4-1-1 Laplacian filter is applied on OBL depth.\n"
+        ),
+        call("%KPP\n"),
+        call("DT = 1800.0\n"),
+        call("BOOL = True\n"),
+    ]
+
+    mock_file().write.assert_has_calls(expected_calls, any_order=False)