Implement Arrow::MakeStructOptions.try_convert

Author: stenlarsson

ruby/red-arrow/lib/arrow/libraries.rb

@@ -81,6 +81,7 @@
 require_relative "list-array-builder"
 require_relative "list-data-type"
 require_relative "list-slice-options"
+require_relative "make-struct-options"
 require_relative "map-array"
 require_relative "map-array-builder"
 require_relative "map-data-type"

ruby/red-arrow/lib/arrow/make-struct-options.rb

@@ -0,0 +1,38 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+module Arrow
+  class MakeStructOptions
+    class << self
+      def try_convert(value)
+        case value
+        when Hash
+          options = new
+          field_names = value[:field_names] || []
+          field_nullability = value[:field_nullability] || []
+          field_metadata = value[:field_metadata] || []
+          field_names.zip(field_nullability, field_metadata) do |name, nullability, metadata|
+            options.add_field(name, nullability, metadata)
+          end
+          options
+        else
+          nil
+        end
+      end
+    end
+  end
+end

ruby/red-arrow/test/test-make-struct-options.rb

@@ -0,0 +1,51 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+class TestMakeStructOptions < Test::Unit::TestCase
+  def test_make_struct_function
+    a = Arrow::Int8Array.new([1, 2, 3])
+    b = Arrow::BooleanArray.new([true, false, nil])
+    metadata1 = {"a" => "b"}
+    metadata2 = {"c" => "d"}
+    options = {
+      field_names: ["a", "b"],
+      field_nullability: [false, true],
+      field_metadata: [metadata1, metadata2]
+    }
+    args = [a, b]
+    make_struct_function = Arrow::Function.find("make_struct")
+    result = make_struct_function.execute(args, options).value
+
+    expected = Arrow::StructArray.new(
+      Arrow::StructDataType.new(
+        [
+          Arrow::Field.new("a", Arrow::Int8DataType.new, false),
+          Arrow::Field.new("b", Arrow::BooleanDataType.new, true),
+        ]
+      ),
+      [
+        {"a" => 1, "b" => true},
+        {"a" => 2, "b" => false},
+        {"a" => 3, "b" => nil},
+      ]
+    )
+    assert_equal(expected, result)
+    fields = result.value_data_type.fields
+    assert_equal(metadata1, fields[0].metadata)
+    assert_equal(metadata2, fields[1].metadata)
+  end
+end