Fixed deprecation warning

Author: ankane

lib/xgboost/dmatrix.rb

@@ -76,9 +76,15 @@ def weight=(weight)
     end
 
     def group=(group)
-      c_data = ::FFI::MemoryPointer.new(:int, group.size)
-      c_data.write_array_of_int(group)
-      check_call FFI.XGDMatrixSetUIntInfo(handle, "group", c_data, group.size)
+      c_data = ::FFI::MemoryPointer.new(:uint, group.size)
+      c_data.write_array_of_uint(group)
+      interface = {
+        shape: [group.length],
+        typestr: "|u4",
+        data: [c_data.address, false],
+        version: 3
+      }
+      check_call FFI.XGDMatrixSetInfoFromInterface(handle, "group", JSON.generate(interface))
     end
 
     def label
@@ -89,6 +95,10 @@ def weight
       float_info("weight")
     end
 
+    def group
+      uint_info("group_ptr")
+    end
+
     def num_row
       out = ::FFI::MemoryPointer.new(:uint64)
       check_call FFI.XGDMatrixNumRow(handle, out)
@@ -234,7 +244,15 @@ def float_info(field)
       out_len = ::FFI::MemoryPointer.new(:uint64)
       out_dptr = ::FFI::MemoryPointer.new(:float, num_row)
       check_call FFI.XGDMatrixGetFloatInfo(handle, field, out_len, out_dptr)
-      out_dptr.read_pointer.read_array_of_float(num_row)
+      out_dptr.read_pointer.null? ? nil : out_dptr.read_pointer.read_array_of_float(num_row)
+    end
+
+    def uint_info(field)
+      num_row ||= num_row()
+      out_len = ::FFI::MemoryPointer.new(:uint64)
+      out_dptr = ::FFI::MemoryPointer.new(:uint, num_row)
+      check_call FFI.XGDMatrixGetUIntInfo(handle, field, out_len, out_dptr)
+      out_dptr.read_pointer.null? ? nil : out_dptr.read_pointer.read_array_of_uint(num_row)
     end
 
     def validate_feature_info(feature_info, n_features, is_column_split, name)

lib/xgboost/ffi.rb

@@ -21,7 +21,7 @@ module FFI
 
     # dmatrix
     attach_function :XGDMatrixCreateFromMat, %i[pointer uint64 uint64 float pointer], :int
-    attach_function :XGDMatrixSetUIntInfo, %i[pointer string pointer uint64], :int
+    attach_function :XGDMatrixSetInfoFromInterface, %i[pointer string string], :int
     attach_function :XGDMatrixSetStrFeatureInfo, %i[pointer string pointer uint64], :int
     attach_function :XGDMatrixGetStrFeatureInfo, %i[pointer string pointer pointer], :int
     attach_function :XGDMatrixNumRow, %i[pointer pointer], :int
@@ -33,6 +33,7 @@ module FFI
     attach_function :XGDMatrixSaveBinary, %i[pointer string int], :int
     attach_function :XGDMatrixSetFloatInfo, %i[pointer string pointer uint64], :int
     attach_function :XGDMatrixGetFloatInfo, %i[pointer string pointer pointer], :int
+    attach_function :XGDMatrixGetUIntInfo, %i[pointer string pointer pointer], :int
 
     # booster
     attach_function :XGBoosterCreate, %i[pointer int pointer], :int

test/dmatrix_test.rb

@@ -5,14 +5,21 @@ def test_label
     data = [[1, 2], [3, 4]]
     label = [1, 2]
     dataset = XGBoost::DMatrix.new(data, label: label)
-    assert label, dataset.label
+    assert_equal label, dataset.label
   end
 
   def test_weight
     data = [[1, 2], [3, 4]]
     weight = [1, 2]
     dataset = XGBoost::DMatrix.new(data, weight: weight)
-    assert weight, dataset.weight
+    assert_equal weight, dataset.weight
+  end
+
+  def test_group
+    data = [[1, 2], [3, 4]]
+    dataset = XGBoost::DMatrix.new(data)
+    dataset.group = [1, 2]
+    assert_equal [0, 1], dataset.group
   end
 
   def test_feature_names_and_types