Use enums GridReg and GridType in test_accessor.py

pygmt/tests/test_accessor.py

@@ -11,6 +11,7 @@
 from pygmt import which
 from pygmt.clib import __gmt_version__
 from pygmt.datasets import load_earth_relief
+from pygmt.enums import GridReg, GridType
 from pygmt.exceptions import GMTInvalidInput
 
 
@@ -21,8 +22,8 @@ def test_accessor_gridline_cartesian():
     """
     fname = which(fname="@test.dat.nc", download="a")
     grid = xr.open_dataarray(fname)
-    assert grid.gmt.registration == 0  # gridline registration
-    assert grid.gmt.gtype == 0  # cartesian coordinate type
+    assert grid.gmt.registration == GridReg.GRIDLINE
+    assert grid.gmt.gtype == GridType.CARTESIAN
 
 
 def test_accessor_pixel_geographic():
@@ -32,18 +33,18 @@ def test_accessor_pixel_geographic():
     """
     fname = which(fname="@earth_relief_01d_p", download="a")
     grid = xr.open_dataarray(fname, engine="netcdf4")
-    assert grid.gmt.registration == 1  # pixel registration
-    assert grid.gmt.gtype == 1  # geographic coordinate type
+    assert grid.gmt.registration == GridReg.PIXEL
+    assert grid.gmt.gtype == GridType.GEOGRAPHIC
 
 
 def test_accessor_set_pixel_registration():
     """
     Check that we can set a grid to be Pixel registered with a registration value of 1.
     """
     grid = xr.DataArray(data=[[0.1, 0.2], [0.3, 0.4]])
-    assert grid.gmt.registration == 0  # default to gridline registration
-    grid.gmt.registration = 1  # set to pixel registration
-    assert grid.gmt.registration == 1  # ensure changed to pixel registration
+    assert grid.gmt.registration == GridReg.GRIDLINE
+    grid.gmt.registration = GridReg.PIXEL
+    assert grid.gmt.registration == GridReg.PIXEL
 
 
 @pytest.mark.benchmark
@@ -53,11 +54,11 @@ def test_accessor_set_geographic_cartesian_roundtrip():
     using a gtype of 1, set it to Geographic 0, and then back to Cartesian again 1.
     """
     grid = xr.DataArray(data=[[0.1, 0.2], [0.3, 0.4]])
-    assert grid.gmt.gtype == 0  # default to cartesian coordinate type
-    grid.gmt.gtype = 1  # set to geographic type
-    assert grid.gmt.gtype == 1  # ensure changed to geographic coordinate type
-    grid.gmt.gtype = 0  # set back to cartesian type
-    assert grid.gmt.gtype == 0  # ensure changed to cartesian coordinate type
+    assert grid.gmt.gtype == GridType.CARTESIAN
+    grid.gmt.gtype = GridType.GEOGRAPHIC
+    assert grid.gmt.gtype == GridType.GEOGRAPHIC
+    grid.gmt.gtype = GridType.CARTESIAN
+    assert grid.gmt.gtype == GridType.CARTESIAN
 
 
 def test_accessor_set_non_boolean():
@@ -93,8 +94,8 @@ def test_accessor_sliced_datacube():
         with xr.open_dataset(fname) as dataset:
             grid = dataset.sel(level=500, month=1, drop=True).z
 
-        assert grid.gmt.registration == 0  # gridline registration
-        assert grid.gmt.gtype == 1  # geographic coordinate type
+        assert grid.gmt.registration == GridReg.GRIDLINE
+        assert grid.gmt.gtype == GridType.GEOGRAPHIC
     finally:
         Path(fname).unlink()
 
@@ -109,19 +110,19 @@ def test_accessor_grid_source_file_not_exist():
         resolution="05m", region=[0, 5, -5, 5], registration="pixel"
     )
     # Registration and gtype are correct
-    assert grid.gmt.registration == 1
-    assert grid.gmt.gtype == 1
+    assert grid.gmt.registration == GridReg.PIXEL
+    assert grid.gmt.gtype == GridType.GEOGRAPHIC
     # The source grid file is undefined.
     assert grid.encoding.get("source") is None
 
     # For a sliced grid, fallback to default registration and gtype,
     # because the source grid file doesn't exist.
     sliced_grid = grid[1:3, 1:3]
-    assert sliced_grid.gmt.registration == 0
-    assert sliced_grid.gmt.gtype == 0
+    assert sliced_grid.gmt.registration == GridReg.GRIDLINE
+    assert sliced_grid.gmt.gtype == GridType.CARTESIAN
 
     # Still possible to manually set registration and gtype
-    sliced_grid.gmt.registration = 1
-    sliced_grid.gmt.gtype = 1
-    assert sliced_grid.gmt.registration == 1
-    assert sliced_grid.gmt.gtype == 1
+    sliced_grid.gmt.registration = GridReg.PIXEL
+    sliced_grid.gmt.gtype = GridType.GEOGRAPHIC
+    assert sliced_grid.gmt.registration == GridReg.PIXEL
+    assert sliced_grid.gmt.gtype == GridType.GEOGRAPHIC