From 670089460b3f393a957a5449defff5c4245924c1 Mon Sep 17 00:00:00 2001
From: Hyukjin Kwon <gurwls223@apache.org>
Date: Fri, 30 Jan 2026 18:53:17 +0900
Subject: [PATCH] Remove the TODO asking to remove check_metadata in compare.cc

---
 cpp/src/arrow/compare.cc   |  2 +-
 cpp/src/arrow/type_test.cc | 25 +++++++++++++++++++++++++
 2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/cpp/src/arrow/compare.cc b/cpp/src/arrow/compare.cc
index 26f56d9b588..a01d0de962b 100644
--- a/cpp/src/arrow/compare.cc
+++ b/cpp/src/arrow/compare.cc
@@ -1513,7 +1513,7 @@ bool TypeEquals(const DataType& left, const DataType& right, bool check_metadata
       return left_fp == right_fp;
     }
 
-    // TODO remove check_metadata here?
+    // Fall back to TypeEqualsVisitor when fingerprints are unavailable.
     TypeEqualsVisitor visitor(right, check_metadata);
     auto error = VisitTypeInline(left, &visitor);
     if (!error.ok()) {
diff --git a/cpp/src/arrow/type_test.cc b/cpp/src/arrow/type_test.cc
index e9b1d30e6e7..a7bef5dc657 100644
--- a/cpp/src/arrow/type_test.cc
+++ b/cpp/src/arrow/type_test.cc
@@ -2004,6 +2004,31 @@ TEST(TestNestedType, Equals) {
   AssertFieldNotEqual(*u0, *u0_bad);
 }
 
+TEST(TestNestedType, FieldMetadataComparisonWithEmptyFingerprints) {
+  // Manual ListType with empty fingerprints to force TypeEqualsVisitor path
+  class EmptyFingerprintListType : public ListType {
+   public:
+    using ListType::ListType;
+
+   protected:
+    std::string ComputeFingerprint() const override { return ""; }
+    std::string ComputeMetadataFingerprint() const override { return ""; }
+  };
+
+  auto metadata1 = key_value_metadata({{"key", "value1"}});
+  auto metadata2 = key_value_metadata({{"key", "value2"}});
+  auto field1 = field("item", int32(), true, metadata1);
+  auto field2 = field("item", int32(), true, metadata2);
+  auto list1 = std::make_shared<EmptyFingerprintListType>(field1);
+  auto list2 = std::make_shared<EmptyFingerprintListType>(field2);
+
+  ASSERT_TRUE(list1->fingerprint().empty());
+  ASSERT_TRUE(list1->metadata_fingerprint().empty());
+
+  EXPECT_TRUE(list1->Equals(*list2, /* check_metadata = */ false));
+  EXPECT_FALSE(list1->Equals(*list2, /* check_metadata = */ true));
+}
+
 TEST(TestStructType, Basics) {
   auto f0_type = int32();
   auto f0 = field("f0", f0_type);