GH-44604: [GLib] Add Decimal32Array (#44617)

### Rationale for this change

The `arrow::Decimal32Array` has been released.
The `GArrowDecimal32Array` class must be implemented in the GLib.

### What changes are included in this PR?

* Implement `GArrowDecimal32Array`
* Implement `GArrowDecimal32ArrayBuilder`

### Are these changes tested?

YES

### Are there any user-facing changes?

NO

* GitHub Issue: #44604

Authored-by: Hiroyuki Sato <[email protected]>
Signed-off-by: Sutou Kouhei <[email protected]>

c_glib/arrow-glib/array-builder.cpp

@@ -457,6 +457,9 @@ G_BEGIN_DECLS
  * #GArrowMapArrayBuilder is the class to create a new
  * #GArrowMapArray.
  *
+ * #GArrowDecimal32ArrayBuilder is the class to create a new
+ * #GArrowDecimal32Array.
+ *
  * #GArrowDecimal64ArrayBuilder is the class to create a new
  * #GArrowDecimal64Array.
  *
@@ -6065,6 +6068,105 @@ garrow_map_array_builder_get_value_builder(GArrowMapArrayBuilder *builder)
   return priv->value_builder;
 }
 
+G_DEFINE_TYPE(GArrowDecimal32ArrayBuilder,
+              garrow_decimal32_array_builder,
+              GARROW_TYPE_FIXED_SIZE_BINARY_ARRAY_BUILDER)
+
+static void
+garrow_decimal32_array_builder_init(GArrowDecimal32ArrayBuilder *builder)
+{
+}
+
+static void
+garrow_decimal32_array_builder_class_init(GArrowDecimal32ArrayBuilderClass *klass)
+{
+}
+
+/**
+ * garrow_decimal32_array_builder_new:
+ * @data_type: #GArrowDecimal32DataType for the decimal.
+ *
+ * Returns: A newly created #GArrowDecimal32ArrayBuilder.
+ *
+ * Since: 19.0.0
+ */
+GArrowDecimal32ArrayBuilder *
+garrow_decimal32_array_builder_new(GArrowDecimal32DataType *data_type)
+{
+  auto arrow_data_type = garrow_data_type_get_raw(GARROW_DATA_TYPE(data_type));
+  auto builder =
+    garrow_array_builder_new(arrow_data_type, NULL, "[decimal32-array-builder][new]");
+  return GARROW_DECIMAL32_ARRAY_BUILDER(builder);
+}
+
+/**
+ * garrow_decimal32_array_builder_append_value:
+ * @builder: A #GArrowDecimal32ArrayBuilder.
+ * @value: (nullable): A decimal value.
+ * @error: (nullable): Return location for a #GError or %NULL.
+ *
+ * Returns: %TRUE on success, %FALSE if there was an error.
+ *
+ * Since: 19.0.0
+ */
+gboolean
+garrow_decimal32_array_builder_append_value(GArrowDecimal32ArrayBuilder *builder,
+                                            GArrowDecimal32 *value,
+                                            GError **error)
+{
+  if (value) {
+    auto arrow_decimal = garrow_decimal32_get_raw(value);
+    return garrow_array_builder_append_value<arrow::Decimal32Builder>(
+      GARROW_ARRAY_BUILDER(builder),
+      *arrow_decimal,
+      error,
+      "[decimal32-array-builder][append-value]");
+  } else {
+    return garrow_array_builder_append_null(GARROW_ARRAY_BUILDER(builder), error);
+  }
+}
+
+/**
+ * garrow_decimal32_array_builder_append_values:
+ * @builder: A #GArrowDecimal32ArrayBuilder.
+ * @values: (array length=values_length): The array of #GArrowDecimal32.
+ * @values_length: The length of @values.
+ * @is_valids: (nullable) (array length=is_valids_length): The array of
+ *   boolean that shows whether the Nth value is valid or not. If the
+ *   Nth @is_valids is %TRUE, the Nth @values is valid value. Otherwise
+ *   the Nth value is null value.
+ * @is_valids_length: The length of @is_valids.
+ * @error: (nullable): Return location for a #GError or %NULL.
+ *
+ * Append multiple values at once. It's more efficient than multiple
+ * `append` and `append_null` calls.
+ *
+ * Returns: %TRUE on success, %FALSE if there was an error.
+ *
+ * Since: 19.0.0
+ */
+gboolean
+garrow_decimal32_array_builder_append_values(GArrowDecimal32ArrayBuilder *builder,
+                                             GArrowDecimal32 **values,
+                                             gint64 values_length,
+                                             const gboolean *is_valids,
+                                             gint64 is_valids_length,
+                                             GError **error)
+{
+  return garrow_array_builder_append_values(
+    GARROW_ARRAY_BUILDER(builder),
+    values,
+    values_length,
+    is_valids,
+    is_valids_length,
+    error,
+    "[decimal32-array-builder][append-values]",
+    [](guint8 *output, GArrowDecimal32 *value, gsize size) {
+      auto arrow_decimal = garrow_decimal32_get_raw(value);
+      arrow_decimal->ToBytes(output);
+    });
+}
+
 G_DEFINE_TYPE(GArrowDecimal64ArrayBuilder,
               garrow_decimal64_array_builder,
               GARROW_TYPE_FIXED_SIZE_BINARY_ARRAY_BUILDER)
@@ -6683,6 +6785,9 @@ garrow_array_builder_new_raw(std::shared_ptr<arrow::ArrayBuilder> *arrow_builder
     case arrow::Type::type::MAP:
       type = GARROW_TYPE_MAP_ARRAY_BUILDER;
       break;
+    case arrow::Type::type::DECIMAL32:
+      type = GARROW_TYPE_DECIMAL32_ARRAY_BUILDER;
+      break;
     case arrow::Type::type::DECIMAL64:
       type = GARROW_TYPE_DECIMAL64_ARRAY_BUILDER;
       break;

c_glib/arrow-glib/array-builder.h

@@ -1729,6 +1729,36 @@ GARROW_AVAILABLE_IN_0_17
 GArrowArrayBuilder *
 garrow_map_array_builder_get_value_builder(GArrowMapArrayBuilder *builder);
 
+#define GARROW_TYPE_DECIMAL32_ARRAY_BUILDER (garrow_decimal32_array_builder_get_type())
+GARROW_AVAILABLE_IN_19_0
+G_DECLARE_DERIVABLE_TYPE(GArrowDecimal32ArrayBuilder,
+                         garrow_decimal32_array_builder,
+                         GARROW,
+                         DECIMAL32_ARRAY_BUILDER,
+                         GArrowFixedSizeBinaryArrayBuilder)
+struct _GArrowDecimal32ArrayBuilderClass
+{
+  GArrowFixedSizeBinaryArrayBuilderClass parent_class;
+};
+
+GARROW_AVAILABLE_IN_19_0
+GArrowDecimal32ArrayBuilder *
+garrow_decimal32_array_builder_new(GArrowDecimal32DataType *data_type);
+
+GARROW_AVAILABLE_IN_19_0
+gboolean
+garrow_decimal32_array_builder_append_value(GArrowDecimal32ArrayBuilder *builder,
+                                            GArrowDecimal32 *value,
+                                            GError **error);
+GARROW_AVAILABLE_IN_19_0
+gboolean
+garrow_decimal32_array_builder_append_values(GArrowDecimal32ArrayBuilder *builder,
+                                             GArrowDecimal32 **values,
+                                             gint64 values_length,
+                                             const gboolean *is_valids,
+                                             gint64 is_valids_length,
+                                             GError **error);
+
 #define GARROW_TYPE_DECIMAL64_ARRAY_BUILDER (garrow_decimal64_array_builder_get_type())
 GARROW_AVAILABLE_IN_19_0
 G_DECLARE_DERIVABLE_TYPE(GArrowDecimal64ArrayBuilder,

c_glib/arrow-glib/basic-array.cpp

@@ -171,6 +171,11 @@ G_BEGIN_DECLS
  * have Arrow format data, you need to use #GArrowMonthDayNanoIntervalArray
  * to create a new array.
  *
+ * #GArrowDecimal32Array is a class for 32-bit decimal array. It can
+ * store zero or more 32-bit decimal data. If you don't have Arrow
+ * format data, you need to use #GArrowDecimal32ArrayBuilder to
+ * create a new array.
+ *
  * #GArrowDecimal64Array is a class for 64-bit decimal array. It can
  * store zero or more 64-bit decimal data. If you don't have Arrow
  * format data, you need to use #GArrowDecimal64ArrayBuilder to
@@ -3095,6 +3100,60 @@ garrow_fixed_size_binary_array_get_values_bytes(GArrowFixedSizeBinaryArray *arra
                             arrow_binary_array->byte_width() * arrow_array->length());
 }
 
+G_DEFINE_TYPE(GArrowDecimal32Array,
+              garrow_decimal32_array,
+              GARROW_TYPE_FIXED_SIZE_BINARY_ARRAY)
+static void
+garrow_decimal32_array_init(GArrowDecimal32Array *object)
+{
+}
+
+static void
+garrow_decimal32_array_class_init(GArrowDecimal32ArrayClass *klass)
+{
+}
+
+/**
+ * garrow_decimal32_array_format_value:
+ * @array: A #GArrowDecimal32Array.
+ * @i: The index of the target value.
+ *
+ * Returns: (transfer full): The formatted @i-th value.
+ *
+ *   It should be freed with g_free() when no longer needed.
+ *
+ * Since: 19.0.0
+ */
+gchar *
+garrow_decimal32_array_format_value(GArrowDecimal32Array *array, gint64 i)
+{
+  auto arrow_array = garrow_array_get_raw(GARROW_ARRAY(array));
+  auto arrow_decimal32_array =
+    std::static_pointer_cast<arrow::Decimal32Array>(arrow_array);
+  auto value = arrow_decimal32_array->FormatValue(i);
+  return g_strndup(value.data(), value.size());
+}
+
+/**
+ * garrow_decimal32_array_get_value:
+ * @array: A #GArrowDecimal32Array.
+ * @i: The index of the target value.
+ *
+ * Returns: (transfer full): The @i-th value.
+ *
+ * Since: 19.0.0
+ */
+GArrowDecimal32 *
+garrow_decimal32_array_get_value(GArrowDecimal32Array *array, gint64 i)
+{
+  auto arrow_array = garrow_array_get_raw(GARROW_ARRAY(array));
+  auto arrow_decimal32_array =
+    std::static_pointer_cast<arrow::Decimal32Array>(arrow_array);
+  auto arrow_decimal32 =
+    std::make_shared<arrow::Decimal32>(arrow_decimal32_array->GetValue(i));
+  return garrow_decimal32_new_raw(&arrow_decimal32);
+}
+
 G_DEFINE_TYPE(GArrowDecimal64Array,
               garrow_decimal64_array,
               GARROW_TYPE_FIXED_SIZE_BINARY_ARRAY)
@@ -3502,6 +3561,9 @@ garrow_array_new_raw_valist(std::shared_ptr<arrow::Array> *arrow_array,
   case arrow::Type::type::DICTIONARY:
     type = GARROW_TYPE_DICTIONARY_ARRAY;
     break;
+  case arrow::Type::type::DECIMAL32:
+    type = GARROW_TYPE_DECIMAL32_ARRAY;
+    break;
   case arrow::Type::type::DECIMAL64:
     type = GARROW_TYPE_DECIMAL64_ARRAY;
     break;

c_glib/arrow-glib/basic-array.h

@@ -810,6 +810,26 @@ GARROW_AVAILABLE_IN_3_0
 GBytes *
 garrow_fixed_size_binary_array_get_values_bytes(GArrowFixedSizeBinaryArray *array);
 
+#define GARROW_TYPE_DECIMAL32_ARRAY (garrow_decimal32_array_get_type())
+GARROW_AVAILABLE_IN_19_0
+G_DECLARE_DERIVABLE_TYPE(GArrowDecimal32Array,
+                         garrow_decimal32_array,
+                         GARROW,
+                         DECIMAL32_ARRAY,
+                         GArrowFixedSizeBinaryArray)
+struct _GArrowDecimal32ArrayClass
+{
+  GArrowFixedSizeBinaryArrayClass parent_class;
+};
+
+GARROW_AVAILABLE_IN_19_0
+gchar *
+garrow_decimal32_array_format_value(GArrowDecimal32Array *array, gint64 i);
+
+GARROW_AVAILABLE_IN_19_0
+GArrowDecimal32 *
+garrow_decimal32_array_get_value(GArrowDecimal32Array *array, gint64 i);
+
 #define GARROW_TYPE_DECIMAL64_ARRAY (garrow_decimal64_array_get_type())
 GARROW_AVAILABLE_IN_19_0
 G_DECLARE_DERIVABLE_TYPE(GArrowDecimal64Array,

c_glib/test/test-decimal32-array.rb

@@ -0,0 +1,37 @@
+# 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 TestDecimal32Array < Test::Unit::TestCase
+  def test_format_value
+    data_type = Arrow::Decimal32DataType.new(8, 2)
+    builder = Arrow::Decimal32ArrayBuilder.new(data_type)
+    decimal = Arrow::Decimal32.new("23423445")
+    builder.append_value(decimal)
+    array = builder.finish
+    assert_equal("234234.45", array.format_value(0))
+  end
+
+  def test_value
+    data_type = Arrow::Decimal32DataType.new(8, 2)
+    builder = Arrow::Decimal32ArrayBuilder.new(data_type)
+    decimal = Arrow::Decimal32.new("23423445")
+    builder.append_value(decimal)
+    array = builder.finish
+    assert_equal("234234.45",
+                 array.get_value(0).to_string_scale(array.value_data_type.scale))
+  end
+end