ARROW-11958: [GLib] Add garrow_chunked_array_combine()

c_glib/arrow-glib/chunked-array.cpp

@@ -330,6 +330,30 @@ garrow_chunked_array_to_string(GArrowChunkedArray *chunked_array, GError **error
   return g_strdup(arrow_chunked_array->ToString().c_str());
 }
 
+/**
+ * garrow_chunked_array_combine:
+ * @chunked_array: A #GArrowChunkedArray.
+ * @error: (nullable): Return location for a #GError or %NULL.
+ *
+ * Returns: (nullable) (transfer full): The combined array that has
+ *   all data in all chunks.
+ *
+ * Since: 4.0.0
+ */
+GArrowArray *
+garrow_chunked_array_combine(GArrowChunkedArray *chunked_array, GError **error)
+{
+  const auto arrow_chunked_array = garrow_chunked_array_get_raw(chunked_array);
+  auto arrow_combined_array = arrow::Concatenate(arrow_chunked_array->chunks());
+  if (garrow::check(error,
+                    arrow_combined_array,
+                    "[chunked-array][combine]")) {
+    return garrow_array_new_raw(&(*arrow_combined_array));
+  } else {
+    return NULL;
+  }
+}
+
 G_END_DECLS
 
 GArrowChunkedArray *

c_glib/arrow-glib/chunked-array.h

@@ -59,5 +59,8 @@ GArrowChunkedArray *garrow_chunked_array_slice(GArrowChunkedArray *chunked_array
                                                guint64 length);
 gchar *garrow_chunked_array_to_string(GArrowChunkedArray *chunked_array,
                                       GError **error);
+GARROW_AVAILABLE_IN_4_0
+GArrowArray *garrow_chunked_array_combine(GArrowChunkedArray *chunked_array,
+                                          GError **error);
 
 G_END_DECLS

c_glib/test/test-chunked-array.rb

@@ -128,4 +128,14 @@ def test_to_s
 ]
     PRETTY_PRINT
   end
+
+  def test_combine
+    chunks = [
+      build_boolean_array([true]),
+      build_boolean_array([false, nil]),
+    ]
+    chunked_array = Arrow::ChunkedArray.new(chunks)
+    assert_equal(build_boolean_array([true, false, nil]),
+                 chunked_array.combine)
+  end
 end