AST-1540 Add tFilter.py with filter-after-stationadd test

steps/test/integration/CMakeLists.txt

@@ -9,6 +9,7 @@ add_python_tests(
   tClipper
   tColumnReader
   tDemix
+  tFilter
   tGainCal
   tGainCalH5Parm
   tIDGImager

steps/test/integration/tFilter.py

+# Copyright (C) 2024 ASTRON (Netherlands Institute for Radio Astronomy)
+# SPDX-License-Identifier: GPL-3.0-or-later
+
+import pytest
+from subprocess import check_call
+
+# Append current directory to system path in order to import testconfig
+import sys
+
+sys.path.append(".")
+
+import testconfig as tcf
+from utils import assert_taql, run_in_tmp_path, untar
+
+"""
+Integration tests for the Filter step.
+
+Script can be invoked in two ways:
+- as standalone from the build/steps/test/integration directory,
+  using `pytest source/Filter.py` (extended with pytest options of your choice)
+- using ctest, see DP3/steps/test/integration/CMakeLists.txt
+"""
+
+MSIN = "tNDPPP-generic.MS"
+
+
+@pytest.fixture(autouse=True)
+def source_env(run_in_tmp_path):
+    untar(f"{tcf.RESOURCEDIR}/{MSIN}.tgz")
+
+
+def test_filter_added_station():
+    """
+    Adds two stations and filters out the first added station.
+    """
+    MSOUT = "out.ms"
+    check_call(
+        [
+            tcf.DP3EXE,
+            "checkparset=1",
+            f"msin={MSIN}",
+            f"msout={MSOUT}",
+            "steps=[stationadder,filter]",
+            "stationadder.stations={CSNEW:[CS001HBA0,CS002HBA0],RSNEW:[RS106HBA,RS208HBA]}",
+            "filter.baseline=!CSNEW",
+            "filter.remove=true",
+        ]
+    )
+
+    taql_command = f"select from {MSOUT}/ANTENNA where NAME='CSNEW'"
+    assert_taql(taql_command, 0)
+
+    taql_command = f"select from {MSOUT}/ANTENNA where NAME='RSNEW'"
+    assert_taql(taql_command, 1)