Initialize ndim value for Points layer using data shape if available (n…

…apari#6593)

# References and relevant issues

Closes napari#6587 

# Description

Add handling for layer dimensionality initialization by using passed
data shape value if available to set `ndim` when kwarg is not passed

napari/layers/points/_tests/test_points.py

@@ -49,6 +49,12 @@ def _make_cycled_properties(values, length):
 def test_empty_points():
     pts = Points()
     assert pts.data.shape == (0, 2)
+    assert pts.ndim == 2
+
+
+def test_3d_empty_points():
+    pts = Points(np.empty((0, 3)))
+    assert pts.ndim == 3
 
 
 def test_empty_points_with_features():

napari/layers/points/points.py

@@ -378,8 +378,15 @@ def __init__(
         shown=True,
         projection_mode='none',
     ) -> None:
-        if ndim is None and scale is not None:
-            ndim = len(scale)
+        if ndim is None:
+            if scale is not None:
+                ndim = len(scale)
+            elif (
+                data is not None
+                and hasattr(data, 'shape')
+                and len(data.shape) == 2
+            ):
+                ndim = data.shape[1]
 
         data, ndim = fix_data_points(data, ndim)