fix: remove unrelated codes

Author: zhjwpku

src/iceberg/util/decimal.cc

@@ -33,12 +33,9 @@
 #include <cmath>
 #include <cstddef>
 #include <cstdint>
-#include <cstring>
 #include <format>
 #include <iomanip>
-#include <iostream>
 #include <limits>
-#include <ostream>
 #include <sstream>
 #include <string>
 #include <string_view>
@@ -451,8 +448,6 @@ Result<Decimal> Decimal::FromString(std::string_view str, int32_t* precision,
     parsed_scale = static_cast<int32_t>(dec.fractional_digits.size());
   }
 
-  // Index 1 is the high part, index 0 is the low part
-  std::array<uint64_t, 2> result_array = {0, 0};
   uint128_t value = 0;
   ShiftAndAdd(dec.while_digits, value);
   ShiftAndAdd(dec.fractional_digits, value);
@@ -791,7 +786,7 @@ struct DecimalRealConversion {
     return x;
   }
 
-  /// An approximate conversion from Decimal128 to Real that guarantees:
+  /// An approximate conversion from Decimal to Real that guarantees:
   /// 1. If the decimal is an integer, the conversion is exact.
   /// 2. If the number of fractional digits is <= RealTraits<Real>::kMantissaDigits (e.g.
   ///    8 for float and 16 for double), the conversion is within 1 ULP of the exact

src/iceberg/util/decimal.h

@@ -257,22 +257,6 @@ class ICEBERG_EXPORT Decimal {
   friend Decimal operator%(const Decimal& lhs, const Decimal& rhs);
 
  private:
-  static constexpr int32_t highIndex() {
-    if constexpr (std::endian::native == std::endian::little) {
-      return 1;
-    } else {
-      return 0;
-    }
-  }
-
-  static constexpr int32_t lowIndex() {
-    if constexpr (std::endian::native == std::endian::little) {
-      return 0;
-    } else {
-      return 1;
-    }
-  }
-
   int128_t data_{0};
 };
 

test/decimal_test.cc

@@ -23,11 +23,9 @@
 #include <bit>
 #include <cmath>
 #include <cstdint>
-#include <vector>
 
 #include <gmock/gmock.h>
 #include <gtest/gtest.h>
-#include <sys/types.h>
 
 #include "iceberg/util/int128.h"
 #include "matchers.h"
@@ -48,11 +46,6 @@ void AssertDecimalFromString(const std::string& s, const Decimal& expected,
   EXPECT_EQ(expected_scale, scale);
 }
 
-Decimal DecimalFromInt128(int128_t value) {
-  return {static_cast<int64_t>(value >> 64),
-          static_cast<uint64_t>(value & 0xFFFFFFFFFFFFFFFFULL)};
-}
-
 }  // namespace
 
 TEST(DecimalTest, Basics) {
@@ -1094,11 +1087,10 @@ TEST(DecimalTestFunctionality, Multiply) {
   for (auto x : std::vector<int128_t>{-INT64_MAX, -INT32_MAX, 0, INT32_MAX, INT64_MAX}) {
     for (auto y :
          std::vector<int128_t>{-INT32_MAX, -32, -2, -1, 0, 1, 2, 32, INT32_MAX}) {
-      Decimal decimal_x = DecimalFromInt128(x);
-      Decimal decimal_y = DecimalFromInt128(y);
+      Decimal decimal_x(x);
+      Decimal decimal_y(y);
       Decimal result = decimal_x * decimal_y;
-      EXPECT_EQ(DecimalFromInt128(x * y), result)
-          << " x: " << decimal_x << " y: " << decimal_y;
+      EXPECT_EQ(Decimal(x * y), result) << " x: " << decimal_x << " y: " << decimal_y;
     }
   }
 }
@@ -1111,11 +1103,10 @@ TEST(DecimalTestFunctionality, Divide) {
 
   for (auto x : std::vector<int128_t>{-INT64_MAX, -INT32_MAX, 0, INT32_MAX, INT64_MAX}) {
     for (auto y : std::vector<int128_t>{-INT32_MAX, -32, -2, -1, 1, 2, 32, INT32_MAX}) {
-      Decimal decimal_x = DecimalFromInt128(x);
-      Decimal decimal_y = DecimalFromInt128(y);
+      Decimal decimal_x(x);
+      Decimal decimal_y(y);
       Decimal result = decimal_x / decimal_y;
-      EXPECT_EQ(DecimalFromInt128(x / y), result)
-          << " x: " << decimal_x << " y: " << decimal_y;
+      EXPECT_EQ(Decimal(x / y), result) << " x: " << decimal_x << " y: " << decimal_y;
     }
   }
 }
@@ -1129,11 +1120,10 @@ TEST(DecimalTestFunctionality, Modulo) {
   // Test some edge cases
   for (auto x : std::vector<int128_t>{-INT64_MAX, -INT32_MAX, 0, INT32_MAX, INT64_MAX}) {
     for (auto y : std::vector<int128_t>{-INT32_MAX, -32, -2, -1, 1, 2, 32, INT32_MAX}) {
-      Decimal decimal_x = DecimalFromInt128(x);
-      Decimal decimal_y = DecimalFromInt128(y);
+      Decimal decimal_x(x);
+      Decimal decimal_y(y);
       Decimal result = decimal_x % decimal_y;
-      EXPECT_EQ(DecimalFromInt128(x % y), result)
-          << " x: " << decimal_x << " y: " << decimal_y;
+      EXPECT_EQ(Decimal(x % y), result) << " x: " << decimal_x << " y: " << decimal_y;
     }
   }
 }
@@ -1206,8 +1196,8 @@ TEST(DecimalTestFunctionality, FitsInPrecision) {
 
 TEST(DecimalTest, LeftShift) {
   auto check = [](int128_t x, uint32_t bits) {
-    auto expected = DecimalFromInt128(x << bits);
-    auto actual = DecimalFromInt128(x) << bits;
+    auto expected = Decimal(x << bits);
+    auto actual = Decimal(x) << bits;
     ASSERT_EQ(actual.low(), expected.low());
     ASSERT_EQ(actual.high(), expected.high());
   };