Fix integer comparison bug (#5211)

* Fix integer comparison bug

Signed-off-by: ljccjlljc <939159710@qq.com>

* commit

Signed-off-by: ljccjlljc <939159710@qq.com>

* Remove generated CI artifacts and update amalgamation

Signed-off-by: ljccjlljc <939159710@qq.com>

* Silence cpplint braces warning in comparison macro

Signed-off-by: ljccjlljc <939159710@qq.com>

* Update amalgamation after cpplint fix

Signed-off-by: ljccjlljc <939159710@qq.com>

* Add mixed signed and unsigned comparison regression test

Signed-off-by: ljccjlljc <939159710@qq.com>

* Clarify mixed signed and unsigned comparison handling

Signed-off-by: ljccjlljc <939159710@qq.com>

* Expand mixed signed and unsigned comparison tests

Signed-off-by: ljccjlljc <939159710@qq.com>

---------

Signed-off-by: ljccjlljc <939159710@qq.com>
This commit is contained in:
ljcjclljc
2026-08-12 09:21:19 +02:00
committed by GitHub
parent 21af527e75
commit 6285225fd0
3 changed files with 97 additions and 6 deletions
+13 -3
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@@ -3652,6 +3652,12 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
// note parentheses around operands are necessary; see
// https://github.com/nlohmann/json/issues/1530
// Mixed signed/unsigned integer comparisons check whether the signed value
// is negative before casting. If it is, the comparison is performed with
// the fixed values -1 and 1, which preserves the ordering relationship
// because any negative signed value is smaller than any unsigned value.
// Otherwise, the non-negative signed value is cast to unsigned before the
// comparison to avoid wraparound.
#define JSON_IMPLEMENT_OPERATOR(op, null_result, unordered_result, default_result) \
const auto lhs_type = lhs.type(); \
const auto rhs_type = rhs.type(); \
@@ -3710,12 +3716,16 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
} \
else if (lhs_type == value_t::number_unsigned && rhs_type == value_t::number_integer) \
{ \
return static_cast<number_integer_t>(lhs.m_data.m_value.number_unsigned) op rhs.m_data.m_value.number_integer; \
return (rhs.m_data.m_value.number_integer < 0) \
? (number_integer_t(1) op number_integer_t(-1)) \
: (lhs.m_data.m_value.number_unsigned op static_cast<number_unsigned_t>(rhs.m_data.m_value.number_integer)); \
} \
else if (lhs_type == value_t::number_integer && rhs_type == value_t::number_unsigned) \
{ \
return lhs.m_data.m_value.number_integer op static_cast<number_integer_t>(rhs.m_data.m_value.number_unsigned); \
} \
return (lhs.m_data.m_value.number_integer < 0) \
? (number_integer_t(-1) op number_integer_t(1)) \
: (static_cast<number_unsigned_t>(lhs.m_data.m_value.number_integer) op rhs.m_data.m_value.number_unsigned); \
} \
else if(compares_unordered(lhs, rhs))\
{\
return (unordered_result);\
+13 -3
View File
@@ -24988,6 +24988,12 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
// note parentheses around operands are necessary; see
// https://github.com/nlohmann/json/issues/1530
// Mixed signed/unsigned integer comparisons check whether the signed value
// is negative before casting. If it is, the comparison is performed with
// the fixed values -1 and 1, which preserves the ordering relationship
// because any negative signed value is smaller than any unsigned value.
// Otherwise, the non-negative signed value is cast to unsigned before the
// comparison to avoid wraparound.
#define JSON_IMPLEMENT_OPERATOR(op, null_result, unordered_result, default_result) \
const auto lhs_type = lhs.type(); \
const auto rhs_type = rhs.type(); \
@@ -25046,12 +25052,16 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
} \
else if (lhs_type == value_t::number_unsigned && rhs_type == value_t::number_integer) \
{ \
return static_cast<number_integer_t>(lhs.m_data.m_value.number_unsigned) op rhs.m_data.m_value.number_integer; \
return (rhs.m_data.m_value.number_integer < 0) \
? (number_integer_t(1) op number_integer_t(-1)) \
: (lhs.m_data.m_value.number_unsigned op static_cast<number_unsigned_t>(rhs.m_data.m_value.number_integer)); \
} \
else if (lhs_type == value_t::number_integer && rhs_type == value_t::number_unsigned) \
{ \
return lhs.m_data.m_value.number_integer op static_cast<number_integer_t>(rhs.m_data.m_value.number_unsigned); \
} \
return (lhs.m_data.m_value.number_integer < 0) \
? (number_integer_t(-1) op number_integer_t(1)) \
: (static_cast<number_unsigned_t>(lhs.m_data.m_value.number_integer) op rhs.m_data.m_value.number_unsigned); \
} \
else if(compares_unordered(lhs, rhs))\
{\
return (unordered_result);\
+71
View File
@@ -15,6 +15,8 @@
#include "doctest_compatibility.h"
#include <cstdint>
#define JSON_TESTS_PRIVATE
#include <nlohmann/json.hpp>
using nlohmann::json;
@@ -255,6 +257,75 @@ TEST_CASE("lexicographical comparison operators")
{f_, f_, f_, f_, f_, f_, f_, f_, f_, f_, f_, f_, f_, f_, f_, f_, f_, f_, f_, f_, f_, f_}, // 21
};
SECTION("signed/unsigned mixed comparison above INT64_MAX")
{
const json above_int64_max = static_cast<std::uint64_t>((std::numeric_limits<std::int64_t>::max)()) + 1ULL;
const json max_uint64 = (std::numeric_limits<std::uint64_t>::max)();
const json negative_one = -1;
const json one = 1;
const json max_int64 = (std::numeric_limits<std::int64_t>::max)();
CHECK_FALSE(above_int64_max == negative_one);
CHECK(above_int64_max != negative_one);
CHECK(negative_one < above_int64_max);
CHECK(negative_one <= above_int64_max);
CHECK_FALSE(negative_one > above_int64_max);
CHECK_FALSE(negative_one >= above_int64_max);
CHECK_FALSE(above_int64_max < negative_one);
CHECK_FALSE(above_int64_max <= negative_one);
CHECK(above_int64_max > negative_one);
CHECK(above_int64_max >= negative_one);
CHECK(negative_one != above_int64_max);
CHECK_FALSE(negative_one == above_int64_max);
CHECK_FALSE(max_uint64 == negative_one);
CHECK(max_uint64 != negative_one);
CHECK(negative_one < max_uint64);
CHECK(negative_one <= max_uint64);
CHECK_FALSE(negative_one > max_uint64);
CHECK_FALSE(negative_one >= max_uint64);
CHECK_FALSE(max_uint64 < negative_one);
CHECK_FALSE(max_uint64 <= negative_one);
CHECK(max_uint64 > negative_one);
CHECK(max_uint64 >= negative_one);
CHECK(negative_one != max_uint64);
CHECK_FALSE(negative_one == max_uint64);
CHECK_FALSE(one == above_int64_max);
CHECK(one != above_int64_max);
CHECK(one < above_int64_max);
CHECK(one <= above_int64_max);
CHECK_FALSE(one > above_int64_max);
CHECK_FALSE(one >= above_int64_max);
CHECK_FALSE(above_int64_max < one);
CHECK_FALSE(above_int64_max <= one);
CHECK(above_int64_max > one);
CHECK(above_int64_max >= one);
CHECK_FALSE(max_int64 == above_int64_max);
CHECK(max_int64 != above_int64_max);
CHECK(max_int64 < above_int64_max);
CHECK(max_int64 <= above_int64_max);
CHECK_FALSE(max_int64 > above_int64_max);
CHECK_FALSE(max_int64 >= above_int64_max);
CHECK_FALSE(above_int64_max < max_int64);
CHECK_FALSE(above_int64_max <= max_int64);
CHECK(above_int64_max > max_int64);
CHECK(above_int64_max >= max_int64);
#if JSON_HAS_THREE_WAY_COMPARISON
// JSON_HAS_CPP_20 (do not remove; see note at top of file)
CHECK((negative_one <=> above_int64_max) == std::partial_ordering::less); // *NOPAD*
CHECK((above_int64_max <=> negative_one) == std::partial_ordering::greater); // *NOPAD*
CHECK((negative_one <=> max_uint64) == std::partial_ordering::less); // *NOPAD*
CHECK((max_uint64 <=> negative_one) == std::partial_ordering::greater); // *NOPAD*
CHECK((one <=> above_int64_max) == std::partial_ordering::less); // *NOPAD*
CHECK((above_int64_max <=> one) == std::partial_ordering::greater); // *NOPAD*
CHECK((max_int64 <=> above_int64_max) == std::partial_ordering::less); // *NOPAD*
CHECK((above_int64_max <=> max_int64) == std::partial_ordering::greater); // *NOPAD*
#endif
}
SECTION("compares unordered")
{
std::vector<std::vector<bool>> expected =