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2
Commits
| Author | SHA1 | Date | |
|---|---|---|---|
 Niels Lohmann
|
4776b9091c | ||
|
Niels Lohmann
|
fd0ca40ea6 |
+14
-121
@@ -3573,7 +3573,6 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
{
|
||||
using std::swap;
|
||||
swap(*(m_data.m_value.array), other);
|
||||
set_parents();
|
||||
}
|
||||
else
|
||||
{
|
||||
@@ -3590,7 +3589,6 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
{
|
||||
using std::swap;
|
||||
swap(*(m_data.m_value.object), other);
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||||
set_parents();
|
||||
}
|
||||
else
|
||||
{
|
||||
@@ -5159,139 +5157,34 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
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||||
|
||||
case value_t::object:
|
||||
{
|
||||
// first pass: record, for every source key, whether it is
|
||||
// common to both objects (in source's iteration order) or
|
||||
// was deleted (i.e., in source but not in target) -- this is
|
||||
// a by-product of the target.find() call already needed to
|
||||
// tell the two cases apart, so it adds no extra lookups. The
|
||||
// "remove" ops themselves are emitted later, interleaved
|
||||
// with the recursive per-key diffs in the fast path below,
|
||||
// to match source's original iteration order (as the
|
||||
// original, pre-reordering-aware implementation did) instead
|
||||
// of grouping all removes before all recursive diffs.
|
||||
std::vector<typename object_t::key_type> common_keys_source_order;
|
||||
// first pass: traverse this object's elements
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||||
for (auto it = source.cbegin(); it != source.cend(); ++it)
|
||||
{
|
||||
// escape the key name to be used in a JSON patch
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||||
const auto path_key = detail::concat<string_t>(path, '/', detail::escape(it.key()));
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||||
|
||||
if (target.find(it.key()) != target.end())
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||||
{
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||||
common_keys_source_order.push_back(it.key());
|
||||
}
|
||||
}
|
||||
|
||||
// second pass: find keys that were added (i.e., in target but
|
||||
// not in source), and record the keys common to both, in
|
||||
// target's iteration order -- again a by-product of the
|
||||
// source.find() call already needed to detect added keys. At
|
||||
// the same time, determine whether every added key comes
|
||||
// after every common key in target's order (a precondition
|
||||
// for the fast path below, which only ever appends new keys
|
||||
// at the very end): for an object_t whose iteration order is
|
||||
// a pure function of the key set (e.g. the default std::map,
|
||||
// which always iterates in sorted key order), the order
|
||||
// check further below is always true and this whole
|
||||
// mechanism is effectively a no-op; it only matters for a
|
||||
// reorderable object_t such as the one backing `ordered_json`.
|
||||
// patch ops for keys that were added (i.e., in target but not
|
||||
// in source); built here so the fast path below can reuse
|
||||
// them without a second source.find() per target key. Only
|
||||
// used by the fast path -- the slow (reordering) path
|
||||
// rebuilds "add" ops for every key itself.
|
||||
std::vector<typename object_t::key_type> common_keys_target_order;
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basic_json added_ops(value_t::array);
|
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bool new_keys_form_suffix = true;
|
||||
bool seen_new_key = false;
|
||||
for (auto it = target.cbegin(); it != target.cend(); ++it)
|
||||
{
|
||||
if (source.find(it.key()) == source.end())
|
||||
{
|
||||
seen_new_key = true;
|
||||
const auto path_key = detail::concat<string_t>(path, '/', detail::escape(it.key()));
|
||||
added_ops.push_back(
|
||||
{
|
||||
{"op", "add"}, {"path", path_key},
|
||||
{"value", it.value()}
|
||||
});
|
||||
// recursive call to compare object values at key it
|
||||
auto temp_diff = diff(it.value(), target[it.key()], path_key);
|
||||
result.insert(result.end(), temp_diff.begin(), temp_diff.end());
|
||||
}
|
||||
else
|
||||
{
|
||||
common_keys_target_order.push_back(it.key());
|
||||
if (seen_new_key)
|
||||
{
|
||||
new_keys_form_suffix = false;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
if (common_keys_source_order == common_keys_target_order && new_keys_form_suffix)
|
||||
{
|
||||
// fast path: order of common keys already matches (or the
|
||||
// object_t's iteration order does not depend on
|
||||
// insertion history), so a plain per-key recursive diff
|
||||
// is correct and minimal, as before. common_keys_source_order
|
||||
// is, by construction, the subsequence of source's keys
|
||||
// that are common to both objects, in source's iteration
|
||||
// order -- so it can be walked in lockstep with `source`
|
||||
// using a cheap key comparison instead of another lookup.
|
||||
// Deleted keys (those source keys not in common_keys_source_order)
|
||||
// are interleaved here too, in source's original order, to
|
||||
// match the historical (pre-reordering-aware) output order.
|
||||
auto common_it = common_keys_source_order.cbegin();
|
||||
for (auto it = source.cbegin(); it != source.cend(); ++it)
|
||||
{
|
||||
if (common_it != common_keys_source_order.cend() && it.key() == *common_it)
|
||||
{
|
||||
const auto path_key = detail::concat<string_t>(path, '/', detail::escape(it.key()));
|
||||
auto temp_diff = diff(it.value(), target[it.key()], path_key);
|
||||
result.insert(result.end(), temp_diff.begin(), temp_diff.end());
|
||||
++common_it;
|
||||
}
|
||||
else
|
||||
{
|
||||
// found a key that is not in target -> remove it
|
||||
const auto path_key = detail::concat<string_t>(path, '/', detail::escape(it.key()));
|
||||
result.push_back(object(
|
||||
{
|
||||
{"op", "remove"}, {"path", path_key}
|
||||
}));
|
||||
}
|
||||
}
|
||||
|
||||
// append the "add" ops for brand-new keys collected above
|
||||
// during the pass over target -- no second source.find()
|
||||
// per target key needed
|
||||
result.insert(result.end(), added_ops.begin(), added_ops.end());
|
||||
}
|
||||
else
|
||||
{
|
||||
// slow path: the common keys are in a different relative
|
||||
// order in source and target (only possible for a
|
||||
// reorderable object_t like ordered_map). Building a
|
||||
// minimal reordering patch is a nontrivial (LCS-like)
|
||||
// problem; instead, remove every source key -- both
|
||||
// deleted keys (which must be removed regardless) and
|
||||
// common keys (removed so they can be re-added in
|
||||
// target's order) -- and re-add every key that should
|
||||
// remain, with its final target value, in target's
|
||||
// order. basic_json::patch()'s "add" operation on an
|
||||
// object uses operator[], which appends at the end for a
|
||||
// vector-backed insertion-ordered map when the key does
|
||||
// not already exist -- so removing a key and then adding
|
||||
// it moves it to the end, fixing its position.
|
||||
for (auto it = source.cbegin(); it != source.cend(); ++it)
|
||||
{
|
||||
const auto path_key = detail::concat<string_t>(path, '/', detail::escape(it.key()));
|
||||
// found a key that is not in o -> remove it
|
||||
result.push_back(object(
|
||||
{
|
||||
{"op", "remove"}, {"path", path_key}
|
||||
}));
|
||||
}
|
||||
}
|
||||
|
||||
// add every key that is either common (just removed
|
||||
// above) or brand new, in target's iteration order, so
|
||||
// that the final order after applying the patch matches
|
||||
// target exactly
|
||||
for (auto it = target.cbegin(); it != target.cend(); ++it)
|
||||
// second pass: traverse other object's elements
|
||||
for (auto it = target.cbegin(); it != target.cend(); ++it)
|
||||
{
|
||||
if (source.find(it.key()) == source.end())
|
||||
{
|
||||
// found a key that is not in this -> add it
|
||||
const auto path_key = detail::concat<string_t>(path, '/', detail::escape(it.key()));
|
||||
result.push_back(
|
||||
{
|
||||
|
||||
@@ -25001,7 +25001,6 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
{
|
||||
using std::swap;
|
||||
swap(*(m_data.m_value.array), other);
|
||||
set_parents();
|
||||
}
|
||||
else
|
||||
{
|
||||
@@ -25018,7 +25017,6 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
{
|
||||
using std::swap;
|
||||
swap(*(m_data.m_value.object), other);
|
||||
set_parents();
|
||||
}
|
||||
else
|
||||
{
|
||||
@@ -26587,139 +26585,34 @@ class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-spec
|
||||
|
||||
case value_t::object:
|
||||
{
|
||||
// first pass: record, for every source key, whether it is
|
||||
// common to both objects (in source's iteration order) or
|
||||
// was deleted (i.e., in source but not in target) -- this is
|
||||
// a by-product of the target.find() call already needed to
|
||||
// tell the two cases apart, so it adds no extra lookups. The
|
||||
// "remove" ops themselves are emitted later, interleaved
|
||||
// with the recursive per-key diffs in the fast path below,
|
||||
// to match source's original iteration order (as the
|
||||
// original, pre-reordering-aware implementation did) instead
|
||||
// of grouping all removes before all recursive diffs.
|
||||
std::vector<typename object_t::key_type> common_keys_source_order;
|
||||
// first pass: traverse this object's elements
|
||||
for (auto it = source.cbegin(); it != source.cend(); ++it)
|
||||
{
|
||||
// escape the key name to be used in a JSON patch
|
||||
const auto path_key = detail::concat<string_t>(path, '/', detail::escape(it.key()));
|
||||
|
||||
if (target.find(it.key()) != target.end())
|
||||
{
|
||||
common_keys_source_order.push_back(it.key());
|
||||
}
|
||||
}
|
||||
|
||||
// second pass: find keys that were added (i.e., in target but
|
||||
// not in source), and record the keys common to both, in
|
||||
// target's iteration order -- again a by-product of the
|
||||
// source.find() call already needed to detect added keys. At
|
||||
// the same time, determine whether every added key comes
|
||||
// after every common key in target's order (a precondition
|
||||
// for the fast path below, which only ever appends new keys
|
||||
// at the very end): for an object_t whose iteration order is
|
||||
// a pure function of the key set (e.g. the default std::map,
|
||||
// which always iterates in sorted key order), the order
|
||||
// check further below is always true and this whole
|
||||
// mechanism is effectively a no-op; it only matters for a
|
||||
// reorderable object_t such as the one backing `ordered_json`.
|
||||
// patch ops for keys that were added (i.e., in target but not
|
||||
// in source); built here so the fast path below can reuse
|
||||
// them without a second source.find() per target key. Only
|
||||
// used by the fast path -- the slow (reordering) path
|
||||
// rebuilds "add" ops for every key itself.
|
||||
std::vector<typename object_t::key_type> common_keys_target_order;
|
||||
basic_json added_ops(value_t::array);
|
||||
bool new_keys_form_suffix = true;
|
||||
bool seen_new_key = false;
|
||||
for (auto it = target.cbegin(); it != target.cend(); ++it)
|
||||
{
|
||||
if (source.find(it.key()) == source.end())
|
||||
{
|
||||
seen_new_key = true;
|
||||
const auto path_key = detail::concat<string_t>(path, '/', detail::escape(it.key()));
|
||||
added_ops.push_back(
|
||||
{
|
||||
{"op", "add"}, {"path", path_key},
|
||||
{"value", it.value()}
|
||||
});
|
||||
// recursive call to compare object values at key it
|
||||
auto temp_diff = diff(it.value(), target[it.key()], path_key);
|
||||
result.insert(result.end(), temp_diff.begin(), temp_diff.end());
|
||||
}
|
||||
else
|
||||
{
|
||||
common_keys_target_order.push_back(it.key());
|
||||
if (seen_new_key)
|
||||
{
|
||||
new_keys_form_suffix = false;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
if (common_keys_source_order == common_keys_target_order && new_keys_form_suffix)
|
||||
{
|
||||
// fast path: order of common keys already matches (or the
|
||||
// object_t's iteration order does not depend on
|
||||
// insertion history), so a plain per-key recursive diff
|
||||
// is correct and minimal, as before. common_keys_source_order
|
||||
// is, by construction, the subsequence of source's keys
|
||||
// that are common to both objects, in source's iteration
|
||||
// order -- so it can be walked in lockstep with `source`
|
||||
// using a cheap key comparison instead of another lookup.
|
||||
// Deleted keys (those source keys not in common_keys_source_order)
|
||||
// are interleaved here too, in source's original order, to
|
||||
// match the historical (pre-reordering-aware) output order.
|
||||
auto common_it = common_keys_source_order.cbegin();
|
||||
for (auto it = source.cbegin(); it != source.cend(); ++it)
|
||||
{
|
||||
if (common_it != common_keys_source_order.cend() && it.key() == *common_it)
|
||||
{
|
||||
const auto path_key = detail::concat<string_t>(path, '/', detail::escape(it.key()));
|
||||
auto temp_diff = diff(it.value(), target[it.key()], path_key);
|
||||
result.insert(result.end(), temp_diff.begin(), temp_diff.end());
|
||||
++common_it;
|
||||
}
|
||||
else
|
||||
{
|
||||
// found a key that is not in target -> remove it
|
||||
const auto path_key = detail::concat<string_t>(path, '/', detail::escape(it.key()));
|
||||
result.push_back(object(
|
||||
{
|
||||
{"op", "remove"}, {"path", path_key}
|
||||
}));
|
||||
}
|
||||
}
|
||||
|
||||
// append the "add" ops for brand-new keys collected above
|
||||
// during the pass over target -- no second source.find()
|
||||
// per target key needed
|
||||
result.insert(result.end(), added_ops.begin(), added_ops.end());
|
||||
}
|
||||
else
|
||||
{
|
||||
// slow path: the common keys are in a different relative
|
||||
// order in source and target (only possible for a
|
||||
// reorderable object_t like ordered_map). Building a
|
||||
// minimal reordering patch is a nontrivial (LCS-like)
|
||||
// problem; instead, remove every source key -- both
|
||||
// deleted keys (which must be removed regardless) and
|
||||
// common keys (removed so they can be re-added in
|
||||
// target's order) -- and re-add every key that should
|
||||
// remain, with its final target value, in target's
|
||||
// order. basic_json::patch()'s "add" operation on an
|
||||
// object uses operator[], which appends at the end for a
|
||||
// vector-backed insertion-ordered map when the key does
|
||||
// not already exist -- so removing a key and then adding
|
||||
// it moves it to the end, fixing its position.
|
||||
for (auto it = source.cbegin(); it != source.cend(); ++it)
|
||||
{
|
||||
const auto path_key = detail::concat<string_t>(path, '/', detail::escape(it.key()));
|
||||
// found a key that is not in o -> remove it
|
||||
result.push_back(object(
|
||||
{
|
||||
{"op", "remove"}, {"path", path_key}
|
||||
}));
|
||||
}
|
||||
}
|
||||
|
||||
// add every key that is either common (just removed
|
||||
// above) or brand new, in target's iteration order, so
|
||||
// that the final order after applying the patch matches
|
||||
// target exactly
|
||||
for (auto it = target.cbegin(); it != target.cend(); ++it)
|
||||
// second pass: traverse other object's elements
|
||||
for (auto it = target.cbegin(); it != target.cend(); ++it)
|
||||
{
|
||||
if (source.find(it.key()) == source.end())
|
||||
{
|
||||
// found a key that is not in this -> add it
|
||||
const auto path_key = detail::concat<string_t>(path, '/', detail::escape(it.key()));
|
||||
result.push_back(
|
||||
{
|
||||
|
||||
@@ -273,36 +273,5 @@ TEST_CASE("Regression tests for extended diagnostics")
|
||||
CHECK(j1["numbers"]["two"] == 2);
|
||||
CHECK(j1["string"] == "t");
|
||||
}
|
||||
|
||||
SECTION("Regression test - swap(array_t&)/swap(object_t&) must update JSON_DIAGNOSTICS parent pointers")
|
||||
{
|
||||
// swap(array_t&)
|
||||
{
|
||||
json j = json::array();
|
||||
json::array_t arr = {json::array({1})};
|
||||
j.swap(arr);
|
||||
|
||||
// parent pointers of the moved-in elements must point into j, not
|
||||
// into the now-defunct free-standing array_t
|
||||
CHECK_THROWS_WITH_AS(j[0][0].get<std::string>(), "[json.exception.type_error.302] (/0/0) type must be string, but is number", json::type_error);
|
||||
|
||||
// must not trigger assert_invariant() in a debug/assert-enabled build
|
||||
json const k = j;
|
||||
CHECK(k == j);
|
||||
}
|
||||
|
||||
// swap(object_t&)
|
||||
{
|
||||
json o = json::object();
|
||||
json::object_t obj = {{"a", json::array({1})}};
|
||||
o.swap(obj);
|
||||
|
||||
CHECK_THROWS_WITH_AS(o["a"][0].get<std::string>(), "[json.exception.type_error.302] (/a/0) type must be string, but is number", json::type_error);
|
||||
|
||||
// must not trigger assert_invariant() in a debug/assert-enabled build
|
||||
json const p = o;
|
||||
CHECK(p == o);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
@@ -0,0 +1,42 @@
|
||||
// __ _____ _____ _____
|
||||
// __| | __| | | | JSON for Modern C++ (supporting code)
|
||||
// | | |__ | | | | | | version 3.12.0
|
||||
// |_____|_____|_____|_|___| https://github.com/nlohmann/json
|
||||
//
|
||||
// SPDX-FileCopyrightText: 2013-2026 Niels Lohmann <https://nlohmann.me>
|
||||
// SPDX-License-Identifier: MIT
|
||||
|
||||
// This file contains the C++17-only part of unit-items.cpp (structured
|
||||
// bindings support for json::items()). It is kept in a separate
|
||||
// translation unit so the (much larger) unit-items.cpp does not need to
|
||||
// be compiled a second time just for this one SECTION.
|
||||
|
||||
#include "doctest_compatibility.h"
|
||||
|
||||
#include <nlohmann/json.hpp>
|
||||
using nlohmann::json;
|
||||
|
||||
#ifdef JSON_HAS_CPP_17
|
||||
#include <map>
|
||||
#include <string>
|
||||
|
||||
TEST_CASE("items()")
|
||||
{
|
||||
SECTION("object")
|
||||
{
|
||||
SECTION("structured bindings")
|
||||
{
|
||||
json j = { {"A", 1}, {"B", 2} };
|
||||
|
||||
std::map<std::string, int> m;
|
||||
|
||||
for (auto const&[key, value] : j.items())
|
||||
{
|
||||
m.emplace(key, value);
|
||||
}
|
||||
|
||||
CHECK(j.get<decltype(m)>() == m);
|
||||
}
|
||||
}
|
||||
}
|
||||
#endif
|
||||
@@ -862,22 +862,6 @@ TEST_CASE("items()")
|
||||
|
||||
CHECK(counter == 3);
|
||||
}
|
||||
|
||||
#ifdef JSON_HAS_CPP_17
|
||||
SECTION("structured bindings")
|
||||
{
|
||||
json j = { {"A", 1}, {"B", 2} };
|
||||
|
||||
std::map<std::string, int> m;
|
||||
|
||||
for (auto const&[key, value] : j.items())
|
||||
{
|
||||
m.emplace(key, value);
|
||||
}
|
||||
|
||||
CHECK(j.get<decltype(m)>() == m);
|
||||
}
|
||||
#endif
|
||||
}
|
||||
|
||||
SECTION("const object")
|
||||
|
||||
@@ -81,84 +81,3 @@ TEST_CASE("regression test for issue #3732 - iteration_proxy_value<iter_impl<ord
|
||||
};
|
||||
static_cast<void>(fn);
|
||||
}
|
||||
|
||||
TEST_CASE("regression test - diff() must account for ordered_json member order")
|
||||
{
|
||||
SECTION("pure reorder, no value changes")
|
||||
{
|
||||
ordered_json a = {{"a", 1}, {"b", 2}};
|
||||
ordered_json b = {{"b", 2}, {"a", 1}};
|
||||
CHECK(a != b); // order-sensitive equality
|
||||
CHECK(a.patch(ordered_json::diff(a, b)) == b);
|
||||
}
|
||||
|
||||
SECTION("new key must land at the front")
|
||||
{
|
||||
ordered_json c = {{"b", 2}};
|
||||
ordered_json e = {{"a", 1}, {"b", 2}};
|
||||
CHECK(c.patch(ordered_json::diff(c, e)) == e);
|
||||
}
|
||||
|
||||
SECTION("reorder plus a value change on one of the reordered keys")
|
||||
{
|
||||
ordered_json a = {{"a", 1}, {"b", 2}};
|
||||
ordered_json b = {{"b", 20}, {"a", 1}};
|
||||
CHECK(a != b);
|
||||
CHECK(a.patch(ordered_json::diff(a, b)) == b);
|
||||
}
|
||||
|
||||
SECTION("reorder plus a deleted key")
|
||||
{
|
||||
ordered_json a = {{"a", 1}, {"b", 2}, {"c", 3}};
|
||||
ordered_json b = {{"b", 2}, {"a", 1}};
|
||||
CHECK(a != b);
|
||||
CHECK(a.patch(ordered_json::diff(a, b)) == b);
|
||||
}
|
||||
|
||||
SECTION("reorder plus a nested value that itself needs a recursive diff")
|
||||
{
|
||||
ordered_json a = {{"a", {{"x", 1}, {"y", 2}}}, {"b", 2}};
|
||||
ordered_json b = {{"b", 2}, {"a", {{"x", 1}, {"y", 99}}}};
|
||||
CHECK(a != b);
|
||||
CHECK(a.patch(ordered_json::diff(a, b)) == b);
|
||||
}
|
||||
|
||||
SECTION("three or more keys shuffled into a different order")
|
||||
{
|
||||
ordered_json a = {{"a", 1}, {"b", 2}, {"c", 3}, {"d", 4}};
|
||||
ordered_json b = {{"d", 4}, {"b", 2}, {"a", 1}, {"c", 3}};
|
||||
CHECK(a != b);
|
||||
CHECK(a.patch(ordered_json::diff(a, b)) == b);
|
||||
}
|
||||
|
||||
SECTION("matching order still produces a minimal patch (fast path unaffected)")
|
||||
{
|
||||
ordered_json a = {{"a", 1}, {"b", 2}, {"c", 3}};
|
||||
ordered_json b = {{"a", 1}, {"b", 20}, {"c", 3}};
|
||||
auto p = ordered_json::diff(a, b);
|
||||
// only the changed value should be touched, not a wholesale remove+add
|
||||
CHECK(p.size() == 1);
|
||||
CHECK(p[0]["op"] == "replace");
|
||||
CHECK(p[0]["path"] == "/b");
|
||||
CHECK(a.patch(p) == b);
|
||||
}
|
||||
|
||||
SECTION("plain json (std::map-backed) is unaffected by same-key-different-insertion-order")
|
||||
{
|
||||
json a;
|
||||
a["b"] = 2;
|
||||
a["a"] = 1;
|
||||
|
||||
json b;
|
||||
b["a"] = 1;
|
||||
b["b"] = 2;
|
||||
|
||||
// std::map iteration is always sorted by key, so a == b regardless of
|
||||
// insertion order, and diff() must still produce the same minimal
|
||||
// (empty) result as before this fix
|
||||
CHECK(a == b);
|
||||
auto p = json::diff(a, b);
|
||||
CHECK(p.empty());
|
||||
CHECK(a.patch(p) == b);
|
||||
}
|
||||
}
|
||||
|
||||
@@ -30,10 +30,6 @@ using nlohmann::json;
|
||||
#include <cstdio>
|
||||
#include "make_test_data_available.hpp"
|
||||
|
||||
#ifdef JSON_HAS_CPP_17
|
||||
#include <variant>
|
||||
#endif
|
||||
|
||||
#include "fifo_map.hpp"
|
||||
|
||||
/////////////////////////////////////////////////////////////////////
|
||||
|
||||
Reference in New Issue
Block a user