r.coin: added tests for r.coin module

raster/r.coin/tests/test_coin.py

@@ -0,0 +1,101 @@
+import pytest
+from grass.script import run_command, parse_command
+
+
+@pytest.fixture(scope="module")
+def setup_maps():
+    """Set up a temporary region and generate test raster maps."""
+
+    run_command("g.region", n=3, s=0, e=3, w=0, res=1)
+
+    # 1 1 2
+    # 1 2 3
+    # 2 2 3
+    run_command(
+        "r.mapcalc",
+        expression=(
+            "map1 = "
+            "if(row() == 1 && col() <= 2, 1, "
+            "if(row() == 1 && col() == 3, 2, "
+            "if(row() == 2 && col() == 1, 1, "
+            "if(row() == 2 && col() == 2, 2, "
+            "if(row() == 2 && col() == 3, 3, "
+            "if(row() == 3 && col() <= 2, 2, 3))))))"
+        ),
+        overwrite=True,
+    )
+
+    # 1 2 2
+    # 2 1 3
+    # 3 3 3
+    run_command(
+        "r.mapcalc",
+        expression=(
+            "map2 = "
+            "if(row() == 1 && col() == 1, 1, "
+            "if(row() == 1 && col() >= 2, 2, "
+            "if(row() == 2 && col() == 1, 2, "
+            "if(row() == 2 && col() == 2, 1, "
+            "if(row() == 2 && col() == 3, 3, "
+            "if(row() >= 3, 3, null()))))))"
+        ),
+        overwrite=True,
+    )
+    yield
+
+    run_command("g.remove", flags="f", type="raster", name=["map1", "map2"])
+
+
+def test_r_coin(setup_maps):
+    """Test the r.coin module."""
+
+    coin_output = parse_command("r.coin", first="map1", second="map2", units="c")
+
+    # Start parsing the output
+    actual_results = []
+    is_data_section = False
+
+    for line in coin_output:
+        # Detect the start of the data section
+        if "|   cat# |" in line:
+            is_data_section = True
+            continue
+
+        # Stop parsing after the data section ends
+        if is_data_section and line.startswith("+"):
+            break
+
+        # Parse rows in the data section
+        if is_data_section:
+            columns = line.split("|")
+            if len(columns) > 2:
+                try:
+                    # Extract categories and counts from the table
+                    cat1 = int(columns[1].strip()[1:])  # Category from the row headr
+                    val1 = int(columns[2].strip())  # Value in column 1
+                    val2 = int(columns[3].strip())  # Value in column 2
+                    val3 = int(columns[4].strip())  # Value in column 3
+
+                    actual_results.extend(
+                        [(cat1, 1, val1), (cat1, 2, val2), (cat1, 3, val3)]
+                    )
+                except ValueError:
+                    # Ignore lines that cannot be parsed as numbers
+                    pass
+
+    expected_results = [
+        (1, 1, 1),
+        (1, 2, 1),
+        (1, 3, 0),
+        (2, 1, 2),
+        (2, 2, 1),
+        (2, 3, 0),
+        (3, 1, 0),
+        (3, 2, 2),
+        (3, 3, 2),
+    ]
+
+    # Assert the parsed results against the expected results
+    assert set(actual_results) == set(
+        expected_results
+    ), f"Expected {expected_results}, but got {actual_results}"