Figure.plot3d: Add a new test for missing z value

Author: seisman

pygmt/tests/test_plot3d.py

@@ -88,6 +88,17 @@ def test_plot3d_fail_1d_array_with_data(data, region):
         fig.plot3d(style="cc", fill="red", transparency=data[:, 2] * 100, **kwargs)
 
 
+def test_plot3d_fail_missing_z(data, region):
+    """
+    Should raise an exception if z is missing.
+    """
+    fig = Figure()
+    with pytest.raises(GMTInvalidInput):
+        fig.plot3d(
+            style="c0.2c", x=data[0], y=data[1], region=region, projection="X10c"
+        )
+
+
 @pytest.mark.mpl_image_compare
 def test_plot3d_projection(data, region):
     """