Add 'json4cpp/' from commit '9a737481aed085fd289f82dff1fa8c3c66627a7e'

git-subtree-dir: json4cpp
git-subtree-mainline: 292baed7ac0cf84263263966ed32ed113cae857f
git-subtree-split: 9a737481aed085fd289f82dff1fa8c3c66627a7e

1 files changed, 1336 insertions, 0 deletions

diff --git a/json4cpp/tests/src/unit-json_patch.cpp b/json4cpp/tests/src/unit-json_patch.cpp
new file mode 100644
index 0000000000..fa375b2271
--- /dev/null
+++ b/json4cpp/tests/src/unit-json_patch.cpp
@@ -0,0 +1,1336 @@
+//     __ _____ _____ _____
+//  __|  |   __|     |   | |  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
+
+#include "doctest_compatibility.h"
+
+#include <nlohmann/json.hpp>
+using nlohmann::json;
+#ifdef JSON_TEST_NO_GLOBAL_UDLS
+    using namespace nlohmann::literals; // NOLINT(google-build-using-namespace)
+#endif
+
+#include <fstream>
+#include "make_test_data_available.hpp"
+
+TEST_CASE("JSON patch")
+{
+    SECTION("examples from RFC 6902")
+    {
+        SECTION("4. Operations")
+        {
+            // the ordering of members in JSON objects is not significant:
+            const json op1 = R"({ "op": "add", "path": "/a/b/c", "value": "foo" })"_json;
+            const json op2 = R"({ "path": "/a/b/c", "op": "add", "value": "foo" })"_json;
+            const json op3 = R"({ "value": "foo", "path": "/a/b/c", "op": "add" })"_json;
+
+            // check if the operation objects are equivalent
+            CHECK(op1 == op2);
+            CHECK(op1 == op3);
+        }
+
+        SECTION("4.1 add")
+        {
+            json const patch1 = R"([{ "op": "add", "path": "/a/b", "value": [ "foo", "bar" ] }])"_json;
+
+            // However, the object itself or an array containing it does need
+            // to exist, and it remains an error for that not to be the case.
+            // For example, an "add" with a target location of "/a/b" starting
+            // with this document
+            json const doc1 = R"({ "a": { "foo": 1 } })"_json;
+
+            // is not an error, because "a" exists, and "b" will be added to
+            // its value.
+            CHECK_NOTHROW(doc1.patch(patch1));
+            auto doc1_ans = R"(
+                {
+                    "a": {
+                        "foo": 1,
+                        "b": [ "foo", "bar" ]
+                    }
+                }
+            )"_json;
+            CHECK(doc1.patch(patch1) == doc1_ans);
+
+            // It is an error in this document:
+            json const doc2 = R"({ "q": { "bar": 2 } })"_json;
+
+            // because "a" does not exist.
+#if JSON_DIAGNOSTIC_POSITIONS
+            CHECK_THROWS_WITH_AS(doc2.patch(patch1), "[json.exception.out_of_range.403] (bytes 0-21) key 'a' not found", json::out_of_range&);
+#else
+            CHECK_THROWS_WITH_AS(doc2.patch(patch1), "[json.exception.out_of_range.403] key 'a' not found", json::out_of_range&);
+#endif
+
+            json const doc3 = R"({ "a": {} })"_json;
+            json const patch2 = R"([{ "op": "add", "path": "/a/b/c", "value": 1 }])"_json;
+
+            // should cause an error because "b" does not exist in doc3
+#if JSON_DIAGNOSTICS
+            CHECK_THROWS_WITH_AS(doc3.patch(patch2), "[json.exception.out_of_range.403] (/a) key 'b' not found", json::out_of_range&);
+#elif JSON_DIAGNOSTIC_POSITIONS
+            CHECK_THROWS_WITH_AS(doc3.patch(patch2), "[json.exception.out_of_range.403] (bytes 7-9) key 'b' not found", json::out_of_range&);
+#else
+            CHECK_THROWS_WITH_AS(doc3.patch(patch2), "[json.exception.out_of_range.403] key 'b' not found", json::out_of_range&);
+#endif
+        }
+
+        SECTION("4.2 remove")
+        {
+            // If removing an element from an array, any elements above the
+            // specified index are shifted one position to the left.
+            json const doc = {1, 2, 3, 4};
+            json const patch = {{{"op", "remove"}, {"path", "/1"}}};
+            CHECK(doc.patch(patch) == json({1, 3, 4}));
+        }
+
+        SECTION("A.1. Adding an Object Member")
+        {
+            // An example target JSON document:
+            json const doc = R"(
+                    { "foo": "bar"}
+                )"_json;
+
+            // A JSON Patch document:
+            json const patch = R"(
+                    [
+                        { "op": "add", "path": "/baz", "value": "qux" }
+                    ]
+                )"_json;
+
+            // The resulting JSON document:
+            json expected = R"(
+                    {
+                        "baz": "qux",
+                        "foo": "bar"
+                    }
+                )"_json;
+
+            // check if patched value is as expected
+            CHECK(doc.patch(patch) == expected);
+
+            // check roundtrip
+            CHECK(doc.patch(json::diff(doc, expected)) == expected);
+        }
+
+        SECTION("A.2. Adding an Array Element")
+        {
+            // An example target JSON document:
+            json const doc = R"(
+                    { "foo": [ "bar", "baz" ] }
+                )"_json;
+
+            // A JSON Patch document:
+            json const patch = R"(
+                    [
+                        { "op": "add", "path": "/foo/1", "value": "qux" }
+                    ]
+                )"_json;
+
+            // The resulting JSON document:
+            json expected = R"(
+                    { "foo": [ "bar", "qux", "baz" ] }
+                )"_json;
+
+            // check if patched value is as expected
+            CHECK(doc.patch(patch) == expected);
+
+            // check roundtrip
+            CHECK(doc.patch(json::diff(doc, expected)) == expected);
+        }
+
+        SECTION("A.3. Removing an Object Member")
+        {
+            // An example target JSON document:
+            json const doc = R"(
+                    {
+                        "baz": "qux",
+                        "foo": "bar"
+                    }
+                )"_json;
+
+            // A JSON Patch document:
+            json const patch = R"(
+                    [
+                        { "op": "remove", "path": "/baz" }
+                    ]
+                )"_json;
+
+            // The resulting JSON document:
+            json expected = R"(
+                    { "foo": "bar" }
+                )"_json;
+
+            // check if patched value is as expected
+            CHECK(doc.patch(patch) == expected);
+
+            // check roundtrip
+            CHECK(doc.patch(json::diff(doc, expected)) == expected);
+        }
+
+        SECTION("A.4. Removing an Array Element")
+        {
+            // An example target JSON document:
+            json const doc = R"(
+                    { "foo": [ "bar", "qux", "baz" ] }
+                )"_json;
+
+            // A JSON Patch document:
+            json const patch = R"(
+                    [
+                        { "op": "remove", "path": "/foo/1" }
+                    ]
+                )"_json;
+
+            // The resulting JSON document:
+            json expected = R"(
+                    { "foo": [ "bar", "baz" ] }
+                )"_json;
+
+            // check if patched value is as expected
+            CHECK(doc.patch(patch) == expected);
+
+            // check roundtrip
+            CHECK(doc.patch(json::diff(doc, expected)) == expected);
+        }
+
+        SECTION("A.5. Replacing a Value")
+        {
+            // An example target JSON document:
+            json const doc = R"(
+                    {
+                        "baz": "qux",
+                        "foo": "bar"
+                    }
+                )"_json;
+
+            // A JSON Patch document:
+            json const patch = R"(
+                    [
+                        { "op": "replace", "path": "/baz", "value": "boo" }
+                    ]
+                )"_json;
+
+            json expected = R"(
+                    {
+                        "baz": "boo",
+                        "foo": "bar"
+                    }
+                )"_json;
+
+            // check if patched value is as expected
+            CHECK(doc.patch(patch) == expected);
+
+            // check roundtrip
+            CHECK(doc.patch(json::diff(doc, expected)) == expected);
+        }
+
+        SECTION("A.6. Moving a Value")
+        {
+            // An example target JSON document:
+            json const doc = R"(
+                    {
+                        "foo": {
+                           "bar": "baz",
+                            "waldo": "fred"
+                        },
+                        "qux": {
+                            "corge": "grault"
+                        }
+                    }
+                )"_json;
+
+            // A JSON Patch document:
+            json const patch = R"(
+                    [
+                        { "op": "move", "from": "/foo/waldo", "path": "/qux/thud" }
+                    ]
+                )"_json;
+
+            // The resulting JSON document:
+            json expected = R"(
+                    {
+                        "foo": {
+                           "bar": "baz"
+                        },
+                        "qux": {
+                            "corge": "grault",
+                            "thud": "fred"
+                        }
+                    }
+                )"_json;
+
+            // check if patched value is as expected
+            CHECK(doc.patch(patch) == expected);
+
+            // check roundtrip
+            CHECK(doc.patch(json::diff(doc, expected)) == expected);
+        }
+
+        SECTION("A.7. Moving a Value")
+        {
+            // An example target JSON document:
+            json const doc = R"(
+                    { "foo": [ "all", "grass", "cows", "eat" ] }
+                )"_json;
+
+            // A JSON Patch document:
+            json const patch = R"(
+                    [
+                        { "op": "move", "from": "/foo/1", "path": "/foo/3" }
+                    ]
+                )"_json;
+
+            // The resulting JSON document:
+            json expected = R"(
+                    { "foo": [ "all", "cows", "eat", "grass" ] }
+                )"_json;
+
+            // check if patched value is as expected
+            CHECK(doc.patch(patch) == expected);
+
+            // check roundtrip
+            CHECK(doc.patch(json::diff(doc, expected)) == expected);
+        }
+
+        SECTION("A.8. Testing a Value: Success")
+        {
+            // An example target JSON document:
+            json doc = R"(
+                    {
+                         "baz": "qux",
+                         "foo": [ "a", 2, "c" ]
+                    }
+                )"_json;
+
+            // A JSON Patch document that will result in successful evaluation:
+            json const patch = R"(
+                    [
+                        { "op": "test", "path": "/baz", "value": "qux" },
+                        { "op": "test", "path": "/foo/1", "value": 2 }
+                    ]
+                )"_json;
+
+            // check if evaluation does not throw
+            CHECK_NOTHROW(doc.patch(patch));
+            // check if patched document is unchanged
+            CHECK(doc.patch(patch) == doc);
+        }
+
+        SECTION("A.9. Testing a Value: Error")
+        {
+            // An example target JSON document:
+            json const doc = R"(
+                    { "baz": "qux" }
+                )"_json;
+
+            // A JSON Patch document that will result in an error condition:
+            json patch = R"(
+                    [
+                        { "op": "test", "path": "/baz", "value": "bar" }
+                    ]
+                )"_json;
+
+            // check that evaluation throws
+            CHECK_THROWS_AS(doc.patch(patch), json::other_error&);
+#if JSON_DIAGNOSTICS
+            CHECK_THROWS_WITH_STD_STR(doc.patch(patch), "[json.exception.other_error.501] (/0) unsuccessful: " + patch[0].dump());
+#elif JSON_DIAGNOSTIC_POSITIONS
+            CHECK_THROWS_WITH_STD_STR(doc.patch(patch), "[json.exception.other_error.501] (bytes 47-95) unsuccessful: " + patch[0].dump());
+#else
+            CHECK_THROWS_WITH_STD_STR(doc.patch(patch), "[json.exception.other_error.501] unsuccessful: " + patch[0].dump());
+#endif
+        }
+
+        SECTION("A.10. Adding a Nested Member Object")
+        {
+            // An example target JSON document:
+            json const doc = R"(
+                    { "foo": "bar" }
+                )"_json;
+
+            // A JSON Patch document:
+            json const patch = R"(
+                    [
+                        { "op": "add", "path": "/child", "value": { "grandchild": { } } }
+                    ]
+                )"_json;
+
+            // The resulting JSON document:
+            json expected = R"(
+                {
+                    "foo": "bar",
+                    "child": {
+                        "grandchild": {
+                        }
+                    }
+                }
+                )"_json;
+
+            // check if patched value is as expected
+            CHECK(doc.patch(patch) == expected);
+
+            // check roundtrip
+            CHECK(doc.patch(json::diff(doc, expected)) == expected);
+        }
+
+        SECTION("A.11. Ignoring Unrecognized Elements")
+        {
+            // An example target JSON document:
+            json const doc = R"(
+                    { "foo": "bar" }
+                )"_json;
+
+            // A JSON Patch document:
+            json const patch = R"(
+                    [
+                        { "op": "add", "path": "/baz", "value": "qux", "xyz": 123 }
+                    ]
+                )"_json;
+
+            json expected = R"(
+                    {
+                        "foo": "bar",
+                        "baz": "qux"
+                    } 
+                )"_json;
+
+            // check if patched value is as expected
+            CHECK(doc.patch(patch) == expected);
+
+            // check roundtrip
+            CHECK(doc.patch(json::diff(doc, expected)) == expected);
+        }
+
+        SECTION("A.12. Adding to a Nonexistent Target")
+        {
+            // An example target JSON document:
+            json const doc = R"(
+                    { "foo": "bar" }
+                )"_json;
+
+            // A JSON Patch document:
+            json const patch = R"(
+                    [
+                        { "op": "add", "path": "/baz/bat", "value": "qux" }
+                    ]
+                )"_json;
+
+            // This JSON Patch document, applied to the target JSON document
+            // above, would result in an error (therefore, it would not be
+            // applied), because the "add" operation's target location that
+            // references neither the root of the document, nor a member of
+            // an existing object, nor a member of an existing array.
+#if JSON_DIAGNOSTIC_POSITIONS
+            CHECK_THROWS_WITH_AS(doc.patch(patch), "[json.exception.out_of_range.403] (bytes 21-37) key 'baz' not found", json::out_of_range&);
+#else
+            CHECK_THROWS_WITH_AS(doc.patch(patch), "[json.exception.out_of_range.403] key 'baz' not found", json::out_of_range&);
+#endif
+        }
+
+        // A.13. Invalid JSON Patch Document
+        // not applicable
+
+        SECTION("A.14. Escape Ordering")
+        {
+            // An example target JSON document:
+            json const doc = R"(
+                    {
+                        "/": 9,
+                        "~1": 10
+                    }
+                )"_json;
+
+            // A JSON Patch document:
+            json const patch = R"(
+                    [
+                        {"op": "test", "path": "/~01", "value": 10}
+                    ]
+                )"_json;
+
+            json expected = R"(
+                    {
+                        "/": 9,
+                        "~1": 10
+                    } 
+                )"_json;
+
+            // check if patched value is as expected
+            CHECK(doc.patch(patch) == expected);
+
+            // check roundtrip
+            CHECK(doc.patch(json::diff(doc, expected)) == expected);
+        }
+
+        SECTION("A.15. Comparing Strings and Numbers")
+        {
+            // An example target JSON document:
+            json const doc = R"(
+                    {
+                        "/": 9,
+                        "~1": 10
+                    } 
+                )"_json;
+
+            // A JSON Patch document that will result in an error condition:
+            json patch = R"(
+                    [
+                        {"op": "test", "path": "/~01", "value": "10"}
+                    ]
+                )"_json;
+
+            // check that evaluation throws
+            CHECK_THROWS_AS(doc.patch(patch), json::other_error&);
+#if JSON_DIAGNOSTICS
+            CHECK_THROWS_WITH_STD_STR(doc.patch(patch), "[json.exception.other_error.501] (/0) unsuccessful: " + patch[0].dump());
+#elif JSON_DIAGNOSTIC_POSITIONS
+            CHECK_THROWS_WITH_STD_STR(doc.patch(patch), "[json.exception.other_error.501] (bytes 47-92) unsuccessful: " + patch[0].dump());
+#else
+            CHECK_THROWS_WITH_STD_STR(doc.patch(patch), "[json.exception.other_error.501] unsuccessful: " + patch[0].dump());
+#endif
+        }
+
+        SECTION("A.16. Adding an Array Value")
+        {
+            // An example target JSON document:
+            json const doc = R"(
+                    { "foo": ["bar"] }
+                )"_json;
+
+            // A JSON Patch document:
+            json const patch = R"(
+                    [
+                        { "op": "add", "path": "/foo/-", "value": ["abc", "def"] }
+                    ]
+                )"_json;
+
+            // The resulting JSON document:
+            json expected = R"(
+                    { "foo": ["bar", ["abc", "def"]] }
+                )"_json;
+
+            // check if patched value is as expected
+            CHECK(doc.patch(patch) == expected);
+
+            // check roundtrip
+            CHECK(doc.patch(json::diff(doc, expected)) == expected);
+        }
+    }
+
+    SECTION("own examples")
+    {
+        SECTION("add")
+        {
+            SECTION("add to the root element")
+            {
+                // If the path is the root of the target document - the
+                // specified value becomes the entire content of the target
+                // document.
+
+                // An example target JSON document:
+                json const doc = 17;
+
+                // A JSON Patch document:
+                json const patch = R"(
+                        [
+                            { "op": "add", "path": "", "value": [1,2,3] }
+                        ]
+                    )"_json;
+
+                // The resulting JSON document:
+                json expected = {1, 2, 3};
+
+                // check if patched value is as expected
+                CHECK(doc.patch(patch) == expected);
+
+                // check roundtrip
+                CHECK(doc.patch(json::diff(doc, expected)) == expected);
+            }
+
+            SECTION("add to end of the array")
+            {
+                // The specified index MUST NOT be greater than the number of
+                // elements in the array. The example below uses and index of
+                // exactly the number of elements in the array which is legal.
+
+                // An example target JSON document:
+                json const doc = {0, 1, 2};
+
+                // A JSON Patch document:
+                json const patch = R"(
+                    [
+                        { "op": "add", "path": "/3", "value": 3 }
+                    ]
+                )"_json;
+
+                // The resulting JSON document:
+                json expected = {0, 1, 2, 3};
+
+                // check if patched value is as expected
+                CHECK(doc.patch(patch) == expected);
+
+                // check roundtrip
+                CHECK(doc.patch(json::diff(doc, expected)) == expected);
+            }
+        }
+
+        SECTION("copy")
+        {
+            // An example target JSON document:
+            json const doc = R"(
+                {
+                    "foo": {
+                        "bar": "baz",
+                        "waldo": "fred"
+                    },
+                    "qux": {
+                       "corge": "grault"
+                    }
+                }
+            )"_json;
+
+            // A JSON Patch document:
+            json const patch = R"(
+                [
+                    { "op": "copy", "from": "/foo/waldo", "path": "/qux/thud" }
+                ]
+            )"_json;
+
+            // The resulting JSON document:
+            json expected = R"(
+                {
+                    "foo": {
+                        "bar": "baz",
+                        "waldo": "fred"
+                    },
+                    "qux": {
+                       "corge": "grault",
+                       "thud": "fred"
+                    }
+                }
+            )"_json;
+
+            // check if patched value is as expected
+            CHECK(doc.patch(patch) == expected);
+
+            // check roundtrip
+            CHECK(doc.patch(json::diff(doc, expected)) == expected);
+        }
+
+        SECTION("replace")
+        {
+            json const j = "string";
+            json const patch = {{{"op", "replace"}, {"path", ""}, {"value", 1}}};
+            CHECK(j.patch(patch) == json(1));
+        }
+
+        SECTION("documentation GIF")
+        {
+            {
+                // a JSON patch
+                json const p1 = R"(
+                     [{"op": "add", "path": "/GB", "value": "London"}]
+                    )"_json;
+
+                // a JSON value
+                json const source = R"(
+                      {"D": "Berlin", "F": "Paris"}
+                    )"_json;
+
+                // apply the patch
+                const json target = source.patch(p1);
+                // target = { "D": "Berlin", "F": "Paris", "GB": "London" }
+                CHECK(target == R"({ "D": "Berlin", "F": "Paris", "GB": "London" })"_json);
+
+                // create a diff from two JSONs
+                const json p2 = json::diff(target, source); // NOLINT(readability-suspicious-call-argument)
+                // p2 = [{"op": "delete", "path": "/GB"}]
+                CHECK(p2 == R"([{"op":"remove","path":"/GB"}])"_json);
+            }
+            {
+                // a JSON value
+                json j = {"good", "bad", "ugly"};
+
+                // a JSON pointer
+                auto ptr = json::json_pointer("/2");
+
+                // use to access elements
+                j[ptr] = {{"it", "cattivo"}};
+                CHECK(j == R"(["good","bad",{"it":"cattivo"}])"_json);
+
+                // use user-defined string literal
+                j["/2/en"_json_pointer] = "ugly";
+                CHECK(j == R"(["good","bad",{"en":"ugly","it":"cattivo"}])"_json);
+
+                const json flat = j.flatten();
+                CHECK(flat == R"({"/0":"good","/1":"bad","/2/en":"ugly","/2/it":"cattivo"})"_json);
+            }
+        }
+    }
+
+    SECTION("errors")
+    {
+        SECTION("unknown operation")
+        {
+            SECTION("not an array")
+            {
+                json const j;
+                json const patch = {{"op", "add"}, {"path", ""}, {"value", 1}};
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.104] parse error: JSON patch must be an array of objects", json::parse_error&);
+            }
+
+            SECTION("not an array of objects")
+            {
+                json const j;
+                json const patch = {"op", "add", "path", "", "value", 1};
+#if JSON_DIAGNOSTICS
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.104] parse error: (/0) JSON patch must be an array of objects", json::parse_error&);
+#else
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.104] parse error: JSON patch must be an array of objects", json::parse_error&);
+#endif
+            }
+
+            SECTION("missing 'op'")
+            {
+                json const j;
+                json const patch = {{{"foo", "bar"}}};
+#if JSON_DIAGNOSTICS
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: (/0) operation must have member 'op'", json::parse_error&);
+#else
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: operation must have member 'op'", json::parse_error&);
+#endif
+            }
+
+            SECTION("non-string 'op'")
+            {
+                json const j;
+                json const patch = {{{"op", 1}}};
+#if JSON_DIAGNOSTICS
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: (/0) operation must have string member 'op'", json::parse_error&);
+#else
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: operation must have string member 'op'", json::parse_error&);
+#endif
+            }
+
+            SECTION("invalid operation")
+            {
+                json const j;
+                json const patch = {{{"op", "foo"}, {"path", ""}}};
+#if JSON_DIAGNOSTICS
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: (/0) operation value 'foo' is invalid", json::parse_error&);
+#else
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: operation value 'foo' is invalid", json::parse_error&);
+#endif
+            }
+        }
+
+        SECTION("add")
+        {
+            SECTION("missing 'path'")
+            {
+                json const j;
+                json const patch = {{{"op", "add"}}};
+#if JSON_DIAGNOSTICS
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: (/0) operation 'add' must have member 'path'", json::parse_error&);
+#else
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: operation 'add' must have member 'path'", json::parse_error&);
+#endif
+            }
+
+            SECTION("non-string 'path'")
+            {
+                json const j;
+                json const patch = {{{"op", "add"}, {"path", 1}}};
+#if JSON_DIAGNOSTICS
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: (/0) operation 'add' must have string member 'path'", json::parse_error&);
+#else
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: operation 'add' must have string member 'path'", json::parse_error&);
+#endif
+            }
+
+            SECTION("missing 'value'")
+            {
+                json const j;
+                json const patch = {{{"op", "add"}, {"path", ""}}};
+#if JSON_DIAGNOSTICS
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: (/0) operation 'add' must have member 'value'", json::parse_error&);
+#else
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: operation 'add' must have member 'value'", json::parse_error&);
+#endif
+            }
+
+            SECTION("invalid array index")
+            {
+                json const j = {1, 2};
+                json const patch = {{{"op", "add"}, {"path", "/4"}, {"value", 4}}};
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.out_of_range.401] array index 4 is out of range", json::out_of_range&);
+            }
+        }
+
+        SECTION("remove")
+        {
+            SECTION("missing 'path'")
+            {
+                json const j;
+                json const patch = {{{"op", "remove"}}};
+#if JSON_DIAGNOSTICS
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: (/0) operation 'remove' must have member 'path'", json::parse_error&);
+#else
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: operation 'remove' must have member 'path'", json::parse_error&);
+#endif
+            }
+
+            SECTION("non-string 'path'")
+            {
+                json const j;
+                json const patch = {{{"op", "remove"}, {"path", 1}}};
+#if JSON_DIAGNOSTICS
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: (/0) operation 'remove' must have string member 'path'", json::parse_error&);
+#else
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: operation 'remove' must have string member 'path'", json::parse_error&);
+#endif
+            }
+
+            SECTION("nonexisting target location (array)")
+            {
+                json const j = {1, 2, 3};
+                json const patch = {{{"op", "remove"}, {"path", "/17"}}};
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.out_of_range.401] array index 17 is out of range", json::out_of_range&);
+            }
+
+            SECTION("nonexisting target location (object)")
+            {
+                json const j = {{"foo", 1}, {"bar", 2}};
+                json const patch = {{{"op", "remove"}, {"path", "/baz"}}};
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.out_of_range.403] key 'baz' not found", json::out_of_range&);
+            }
+
+            SECTION("root element as target location")
+            {
+                json const j = "string";
+                json const patch = {{{"op", "remove"}, {"path", ""}}};
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.out_of_range.405] JSON pointer has no parent", json::out_of_range&);
+            }
+        }
+
+        SECTION("replace")
+        {
+            SECTION("missing 'path'")
+            {
+                json const j;
+                json const patch = {{{"op", "replace"}}};
+#if JSON_DIAGNOSTICS
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: (/0) operation 'replace' must have member 'path'", json::parse_error&);
+#else
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: operation 'replace' must have member 'path'", json::parse_error&);
+#endif
+            }
+
+            SECTION("non-string 'path'")
+            {
+                json const j;
+                json const patch = {{{"op", "replace"}, {"path", 1}}};
+#if JSON_DIAGNOSTICS
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: (/0) operation 'replace' must have string member 'path'", json::parse_error&);
+#else
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: operation 'replace' must have string member 'path'", json::parse_error&);
+#endif
+            }
+
+            SECTION("missing 'value'")
+            {
+                json const j;
+                json const patch = {{{"op", "replace"}, {"path", ""}}};
+#if JSON_DIAGNOSTICS
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: (/0) operation 'replace' must have member 'value'", json::parse_error&);
+#else
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: operation 'replace' must have member 'value'", json::parse_error&);
+#endif
+            }
+
+            SECTION("nonexisting target location (array)")
+            {
+                json const j = {1, 2, 3};
+                json const patch = {{{"op", "replace"}, {"path", "/17"}, {"value", 19}}};
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.out_of_range.401] array index 17 is out of range", json::out_of_range&);
+            }
+
+            SECTION("nonexisting target location (object)")
+            {
+                json const j = {{"foo", 1}, {"bar", 2}};
+                json const patch = {{{"op", "replace"}, {"path", "/baz"}, {"value", 3}}};
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.out_of_range.403] key 'baz' not found", json::out_of_range&);
+            }
+        }
+
+        SECTION("move")
+        {
+            SECTION("missing 'path'")
+            {
+                json const j;
+                json const patch = {{{"op", "move"}}};
+#if JSON_DIAGNOSTICS
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: (/0) operation 'move' must have member 'path'", json::parse_error&);
+#else
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: operation 'move' must have member 'path'", json::parse_error&);
+#endif
+            }
+
+            SECTION("non-string 'path'")
+            {
+                json const j;
+                json const patch = {{{"op", "move"}, {"path", 1}}};
+#if JSON_DIAGNOSTICS
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: (/0) operation 'move' must have string member 'path'", json::parse_error&);
+#else
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: operation 'move' must have string member 'path'", json::parse_error&);
+#endif
+            }
+
+            SECTION("missing 'from'")
+            {
+                json const j;
+                json const patch = {{{"op", "move"}, {"path", ""}}};
+                CHECK_THROWS_AS(j.patch(patch), json::parse_error&);
+#if JSON_DIAGNOSTICS
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: (/0) operation 'move' must have member 'from'", json::parse_error&);
+#else
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: operation 'move' must have member 'from'", json::parse_error&);
+#endif
+            }
+
+            SECTION("non-string 'from'")
+            {
+                json const j;
+                json const patch = {{{"op", "move"}, {"path", ""}, {"from", 1}}};
+                CHECK_THROWS_AS(j.patch(patch), json::parse_error&);
+#if JSON_DIAGNOSTICS
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: (/0) operation 'move' must have string member 'from'", json::parse_error&);
+#else
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: operation 'move' must have string member 'from'", json::parse_error&);
+#endif
+            }
+
+            SECTION("nonexisting from location (array)")
+            {
+                json const j = {1, 2, 3};
+                json const patch = {{{"op", "move"}, {"path", "/0"}, {"from", "/5"}}};
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.out_of_range.401] array index 5 is out of range", json::out_of_range&);
+            }
+
+            SECTION("nonexisting from location (object)")
+            {
+                json const j = {{"foo", 1}, {"bar", 2}};
+                json const patch = {{{"op", "move"}, {"path", "/baz"}, {"from", "/baz"}}};
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.out_of_range.403] key 'baz' not found", json::out_of_range&);
+            }
+        }
+
+        SECTION("copy")
+        {
+            SECTION("missing 'path'")
+            {
+                json const j;
+                json const patch = {{{"op", "copy"}}};
+#if JSON_DIAGNOSTICS
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: (/0) operation 'copy' must have member 'path'", json::parse_error&);
+#else
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: operation 'copy' must have member 'path'", json::parse_error&);
+#endif
+            }
+
+            SECTION("non-string 'path'")
+            {
+                json const j;
+                json const patch = {{{"op", "copy"}, {"path", 1}}};
+#if JSON_DIAGNOSTICS
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: (/0) operation 'copy' must have string member 'path'", json::parse_error&);
+#else
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: operation 'copy' must have string member 'path'", json::parse_error&);
+#endif
+            }
+
+            SECTION("missing 'from'")
+            {
+                json const j;
+                json const patch = {{{"op", "copy"}, {"path", ""}}};
+#if JSON_DIAGNOSTICS
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: (/0) operation 'copy' must have member 'from'", json::parse_error&);
+#else
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: operation 'copy' must have member 'from'", json::parse_error&);
+#endif
+            }
+
+            SECTION("non-string 'from'")
+            {
+                json const j;
+                json const patch = {{{"op", "copy"}, {"path", ""}, {"from", 1}}};
+#if JSON_DIAGNOSTICS
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: (/0) operation 'copy' must have string member 'from'", json::parse_error&);
+#else
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: operation 'copy' must have string member 'from'", json::parse_error&);
+#endif
+            }
+
+            SECTION("nonexisting from location (array)")
+            {
+                json const j = {1, 2, 3};
+                json const patch = {{{"op", "copy"}, {"path", "/0"}, {"from", "/5"}}};
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.out_of_range.401] array index 5 is out of range", json::out_of_range&);
+            }
+
+            SECTION("nonexisting from location (object)")
+            {
+                json const j = {{"foo", 1}, {"bar", 2}};
+                json const patch = {{{"op", "copy"}, {"path", "/fob"}, {"from", "/baz"}}};
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.out_of_range.403] key 'baz' not found", json::out_of_range&);
+            }
+        }
+
+        SECTION("test")
+        {
+            SECTION("missing 'path'")
+            {
+                json const j;
+                json const patch = {{{"op", "test"}}};
+#if JSON_DIAGNOSTICS
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: (/0) operation 'test' must have member 'path'", json::parse_error&);
+#else
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: operation 'test' must have member 'path'", json::parse_error&);
+#endif
+            }
+
+            SECTION("non-string 'path'")
+            {
+                json const j;
+                json const patch = {{{"op", "test"}, {"path", 1}}};
+#if JSON_DIAGNOSTICS
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: (/0) operation 'test' must have string member 'path'", json::parse_error&);
+#else
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: operation 'test' must have string member 'path'", json::parse_error&);
+#endif
+            }
+
+            SECTION("missing 'value'")
+            {
+                json const j;
+                json const patch = {{{"op", "test"}, {"path", ""}}};
+#if JSON_DIAGNOSTICS
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: (/0) operation 'test' must have member 'value'", json::parse_error&);
+#else
+                CHECK_THROWS_WITH_AS(j.patch(patch), "[json.exception.parse_error.105] parse error: operation 'test' must have member 'value'", json::parse_error&);
+#endif
+            }
+        }
+    }
+
+    SECTION("Examples from jsonpatch.com")
+    {
+        SECTION("Simple Example")
+        {
+            // The original document
+            json const doc = R"(
+                {
+                  "baz": "qux",
+                  "foo": "bar"
+                }
+            )"_json;
+
+            // The patch
+            json const patch = R"(
+                [
+                  { "op": "replace", "path": "/baz", "value": "boo" },
+                  { "op": "add", "path": "/hello", "value": ["world"] },
+                  { "op": "remove", "path": "/foo"}
+                ]
+            )"_json;
+
+            // The result
+            json result = R"(
+                {
+                   "baz": "boo",
+                   "hello": ["world"]
+                }
+            )"_json;
+
+            // check if patched value is as expected
+            CHECK(doc.patch(patch) == result);
+
+            // check roundtrip
+            CHECK(doc.patch(json::diff(doc, result)) == result);
+        }
+
+        SECTION("Operations")
+        {
+            // The original document
+            json const doc = R"(
+                {
+                  "biscuits": [
+                    {"name":"Digestive"},
+                    {"name": "Choco Liebniz"}
+                  ]
+                }
+            )"_json;
+
+            SECTION("add")
+            {
+                // The patch
+                json const patch = R"(
+                    [
+                        {"op": "add", "path": "/biscuits/1", "value": {"name": "Ginger Nut"}}
+                    ]
+                )"_json;
+
+                // The result
+                json result = R"(
+                    {
+                      "biscuits": [
+                        {"name": "Digestive"},
+                        {"name": "Ginger Nut"},
+                        {"name": "Choco Liebniz"}
+                      ]
+                    }
+                )"_json;
+
+                // check if patched value is as expected
+                CHECK(doc.patch(patch) == result);
+
+                // check roundtrip
+                CHECK(doc.patch(json::diff(doc, result)) == result);
+            }
+
+            SECTION("remove")
+            {
+                // The patch
+                json const patch = R"(
+                    [
+                        {"op": "remove", "path": "/biscuits"}
+                    ]
+                )"_json;
+
+                // The result
+                json result = R"(
+                    {}
+                )"_json;
+
+                // check if patched value is as expected
+                CHECK(doc.patch(patch) == result);
+
+                // check roundtrip
+                CHECK(doc.patch(json::diff(doc, result)) == result);
+            }
+
+            SECTION("replace")
+            {
+                // The patch
+                json const patch = R"(
+                    [
+                        {"op": "replace", "path": "/biscuits/0/name", "value": "Chocolate Digestive"}
+                    ]
+                )"_json;
+
+                // The result
+                json result = R"(
+                    {
+                      "biscuits": [
+                        {"name": "Chocolate Digestive"},
+                        {"name": "Choco Liebniz"}
+                      ]
+                    }
+                )"_json;
+
+                // check if patched value is as expected
+                CHECK(doc.patch(patch) == result);
+
+                // check roundtrip
+                CHECK(doc.patch(json::diff(doc, result)) == result);
+            }
+
+            SECTION("copy")
+            {
+                // The patch
+                json const patch = R"(
+                    [
+                        {"op": "copy", "from": "/biscuits/0", "path": "/best_biscuit"}
+                    ]
+                )"_json;
+
+                // The result
+                json result = R"(
+                    {
+                      "biscuits": [
+                        {"name": "Digestive"},
+                        {"name": "Choco Liebniz"}
+                      ],
+                      "best_biscuit": {
+                        "name": "Digestive"
+                      }
+                    }
+                )"_json;
+
+                // check if patched value is as expected
+                CHECK(doc.patch(patch) == result);
+
+                // check roundtrip
+                CHECK(doc.patch(json::diff(doc, result)) == result);
+            }
+
+            SECTION("move")
+            {
+                // The patch
+                json const patch = R"(
+                    [
+                        {"op": "move", "from": "/biscuits", "path": "/cookies"}
+                    ]
+                )"_json;
+
+                // The result
+                json result = R"(
+                    {
+                      "cookies": [
+                        {"name": "Digestive"},
+                        {"name": "Choco Liebniz"}
+                      ]
+                    }
+                )"_json;
+
+                // check if patched value is as expected
+                CHECK(doc.patch(patch) == result);
+
+                // check roundtrip
+                CHECK(doc.patch(json::diff(doc, result)) == result);
+            }
+
+            SECTION("test")
+            {
+                // The patch
+                json patch = R"(
+                    [
+                        {"op": "test", "path": "/best_biscuit/name", "value": "Choco Liebniz"}
+                    ]
+                )"_json;
+
+                // the test will fail
+                CHECK_THROWS_AS(doc.patch(patch), json::other_error&);
+#if JSON_DIAGNOSTICS
+                CHECK_THROWS_WITH_STD_STR(doc.patch(patch), "[json.exception.other_error.501] (/0) unsuccessful: " + patch[0].dump());
+#elif JSON_DIAGNOSTIC_POSITIONS
+                CHECK_THROWS_WITH_STD_STR(doc.patch(patch), "[json.exception.other_error.501] (bytes 47-117) unsuccessful: " + patch[0].dump());
+#else
+                CHECK_THROWS_WITH_STD_STR(doc.patch(patch), "[json.exception.other_error.501] unsuccessful: " + patch[0].dump());
+#endif
+            }
+        }
+    }
+
+    SECTION("Examples from bruth.github.io/jsonpatch-js")
+    {
+        SECTION("add")
+        {
+            CHECK(R"( {} )"_json.patch(
+                      R"( [{"op": "add", "path": "/foo", "value": "bar"}] )"_json
+                  ) == R"( {"foo": "bar"} )"_json);
+
+            CHECK(R"( {"foo": [1, 3]} )"_json.patch(
+                      R"( [{"op": "add", "path": "/foo", "value": "bar"}] )"_json
+                  ) == R"( {"foo": "bar"} )"_json);
+
+            CHECK(R"( {"foo": [{}]} )"_json.patch(
+                      R"( [{"op": "add", "path": "/foo/0/bar", "value": "baz"}] )"_json
+                  ) == R"( {"foo": [{"bar": "baz"}]} )"_json);
+        }
+
+        SECTION("remove")
+        {
+            CHECK(R"( {"foo": "bar"} )"_json.patch(
+                      R"( [{"op": "remove", "path": "/foo"}] )"_json
+                  ) == R"( {} )"_json);
+
+            CHECK(R"( {"foo": [1, 2, 3]} )"_json.patch(
+                      R"( [{"op": "remove", "path": "/foo/1"}] )"_json
+                  ) == R"( {"foo": [1, 3]} )"_json);
+
+            CHECK(R"( {"foo": [{"bar": "baz"}]} )"_json.patch(
+                      R"( [{"op": "remove", "path": "/foo/0/bar"}] )"_json
+                  ) == R"( {"foo": [{}]} )"_json);
+        }
+
+        SECTION("replace")
+        {
+            CHECK(R"( {"foo": "bar"} )"_json.patch(
+                      R"( [{"op": "replace", "path": "/foo", "value": 1}] )"_json
+                  ) == R"( {"foo": 1} )"_json);
+
+            CHECK(R"( {"foo": [1, 2, 3]} )"_json.patch(
+                      R"( [{"op": "replace", "path": "/foo/1", "value": 4}] )"_json
+                  ) == R"( {"foo": [1, 4, 3]} )"_json);
+
+            CHECK(R"( {"foo": [{"bar": "baz"}]} )"_json.patch(
+                      R"( [{"op": "replace", "path": "/foo/0/bar", "value": 1}] )"_json
+                  ) == R"( {"foo": [{"bar": 1}]} )"_json);
+        }
+
+        SECTION("move")
+        {
+            CHECK(R"( {"foo": [1, 2, 3]} )"_json.patch(
+                      R"( [{"op": "move", "from": "/foo", "path": "/bar"}] )"_json
+                  ) == R"( {"bar": [1, 2, 3]} )"_json);
+        }
+
+        SECTION("copy")
+        {
+            CHECK(R"( {"foo": [1, 2, 3]} )"_json.patch(
+                      R"( [{"op": "copy", "from": "/foo/1", "path": "/bar"}] )"_json
+                  ) == R"( {"foo": [1, 2, 3], "bar": 2} )"_json);
+        }
+
+        SECTION("copy")
+        {
+            CHECK_NOTHROW(R"( {"foo": "bar"} )"_json.patch(
+                              R"( [{"op": "test", "path": "/foo", "value": "bar"}] )"_json));
+        }
+    }
+
+    SECTION("Tests from github.com/json-patch/json-patch-tests")
+    {
+        for (const auto* filename :
+                {
+                    TEST_DATA_DIRECTORY "/json-patch-tests/spec_tests.json",
+                    TEST_DATA_DIRECTORY "/json-patch-tests/tests.json"
+                })
+        {
+            CAPTURE(filename)
+            std::ifstream f(filename);
+            json const suite = json::parse(f);
+
+            for (const auto& test : suite)
+            {
+                INFO_WITH_TEMP(test.value("comment", ""));
+
+                // skip tests marked as disabled
+                if (test.value("disabled", false))
+                {
+                    continue;
+                }
+
+                const auto& doc = test["doc"];
+                const auto& patch = test["patch"];
+
+                if (test.count("error") == 0) // NOLINT(readability-container-contains)
+                {
+                    // if an expected value is given, use it; use doc otherwise
+                    const auto& expected = test.value("expected", doc);
+                    CHECK(doc.patch(patch) == expected);
+                }
+                else
+                {
+                    CHECK_THROWS(doc.patch(patch));
+                }
+            }
+        }
+    }
+}