r.basins.fill: Fix Broken Tests and Preserve Test Dataset Integrity

raster/r.basins.fill/testsuite/test_r_basins_fill.py

@@ -0,0 +1,109 @@
+"""
+Name:       r.basins.fill
+Purpose:    Tests r.basins.fill and its flags/options.
+
+Author:     Sunveer Singh
+Copyright:  (C) 2017 by Sunveer Singh and the GRASS Development Team
+Licence:    This program is free software under the GNU General Public
+            License (>=v2). Read the file COPYING that comes with GRASS
+            for details.
+"""
+
+from grass.gunittest.case import TestCase
+import grass.script as gs
+
+
+def get_categories(map_name):
+    """
+    Retrieve unique integer category values for a given raster map using r.stats.
+    """
+    stats = gs.read_command("r.stats", flags="nc", input=map_name, quiet=True).strip()
+    return {int(line.split()[0]) for line in stats.splitlines() if line}
+
+
+class TestRasterbasin(TestCase):
+    """Test case for r.basins.fill module"""
+
+    # Setup variables to be used for outputs
+    streams = "test_streams"
+    geomorphons = "test_geomorphons"
+    ridges = "test_ridges"
+    subbasins = "test_subbasins"
+
+    @classmethod
+    def setUpClass(cls):
+        cls.use_temp_region()
+        # Set the computational region based on the "elevation" map.
+        cls.runModule("g.region", n=220000, s=218000, e=640000, w=632000, res=10)
+        # Run r.watershed to generate the coded stream network.
+        cls.runModule(
+            "r.watershed",
+            elevation="elevation",
+            threshold=1000,
+            stream=cls.streams,
+        )
+        # Ensure null values are replaced with 0 in streams
+        cls.runModule("r.null", map=cls.streams, null=0)
+
+        # Run r.geomorphon to generate geomorphometric forms.
+        cls.runModule(
+            "r.geomorphon",
+            elevation="elevation",
+            forms=cls.geomorphons,
+            search=36,
+            skip=6,
+            quiet=True,
+        )
+        # Extract ridges from the geomorphon output.
+        cls.runModule(
+            "r.mapcalc", expression=f"{cls.ridges} = if({cls.geomorphons}==3,1,0)"
+        )
+
+    @classmethod
+    def tearDownClass(cls):
+        """Remove temporary maps and region created during the test."""
+        cls.runModule(
+            "g.remove",
+            flags="f",
+            type="raster",
+            name=[cls.streams, cls.ridges, cls.subbasins, cls.geomorphons],
+        )
+        cls.del_temp_region()
+
+    def test_r_basins_fill_method(self):
+        """Test r.basins.fill to verify that it generates the correct watershed subbasins raster map."""
+
+        self.assertModule(
+            "r.basins.fill",
+            cnetwork=self.streams,
+            tnetwork=self.ridges,
+            output=self.subbasins,
+            number=2,
+        )
+
+        self.assertRasterExists(self.subbasins)
+        self.assertRasterMinMax(
+            map=self.subbasins,
+            refmin=0,
+            refmax=2482,
+            msg="subbasins in degrees must be between 0 and 2482",
+        )
+
+        # Retrieve unique category values from the streams and subbasins maps.
+        streams_cats = get_categories(self.streams)
+        self.assertTrue(streams_cats, "No categories found in the 'streams' map.")
+
+        subbasins_cats = get_categories(self.subbasins)
+        self.assertTrue(subbasins_cats, "No categories found in the 'subbasins' map.")
+
+        # Check that every nonzero channel code in subbasins is present in the streams map.
+        self.assertTrue(
+            subbasins_cats.issubset(streams_cats),
+            "Missing basins for some stream codes",
+        )
+
+
+if __name__ == "__main__":
+    from grass.gunittest.main import test
+
+    test()