Merge branch 'develop' into natvis-json-default-base

Signed-off-by: Niels Lohmann <mail@nlohmann.me>

docs/mkdocs/docs/api/basic_json/operator[].md

@@ -128,13 +128,10 @@ Strong exception safety: if an exception occurs, the original value stays intact
 
         When the JSON pointer traverses intermediate levels that don't exist at all yet (not just a missing
         leaf), each missing level is created as an array or an object depending on whether the corresponding
-        pointer token is a valid array index: the token `0`, a sequence of digits that does not begin with `0`,
-        or the token `-` creates an array, and every other token creates an object. For example, on an
-        initially `#!json null` value, `/foo/0/0/0` creates nested arrays, while `/foo/one/one/one` creates
-        nested objects. Tokens such as `01` or the empty token cannot be array indices (cf. RFC 6901, Sect. 4)
-        and therefore create objects, just as they would if the level already existed as an object. This is not
-        specified by the JSON Pointer RFC; it is this library's own, intentional disambiguation rule. See also
-        [JSON Pointer](../../features/json_pointer.md).
+        pointer token parses as a non-negative integer: a numeric token creates an array, a non-numeric token
+        creates an object. For example, on an initially `#!json null` value, `/foo/0/0/0` creates nested arrays,
+        while `/foo/one/one/one` creates nested objects. This is not specified by the JSON Pointer RFC; it is
+        this library's own, intentional disambiguation rule. See also [JSON Pointer](../../features/json_pointer.md).
 
 ## Examples
 

include/nlohmann/detail/json_pointer.hpp

@@ -416,19 +416,15 @@ class json_pointer
             // convert null values to arrays or objects before continuing
             if (ptr->is_null())
             {
-                // check if the reference token is a valid array index, that is
-                // a nonempty sequence of digits without a leading '0'
-                // (cf. RFC 6901, Sect. 4); tokens that could never be a valid
-                // array index (such as "01" or "") are treated as object keys
-                const bool nums = !reference_token.empty()
-                                  && (reference_token.size() == 1 || reference_token[0] != '0')
-                                  && std::all_of(reference_token.begin(), reference_token.end(),
-                                                 [](const unsigned char x)
+                // check if the reference token is a number
+                const bool nums =
+                    std::all_of(reference_token.begin(), reference_token.end(),
+                                [](const unsigned char x)
                 {
                     return std::isdigit(x);
                 });
 
-                // change value to an array for array indices or "-" or to object otherwise
+                // change value to an array for numbers or "-" or to object otherwise
                 *ptr = (nums || reference_token == "-")
                        ? detail::value_t::array
                        : detail::value_t::object;

single_include/nlohmann/json.hpp

@@ -19060,19 +19060,15 @@ class json_pointer
             // convert null values to arrays or objects before continuing
             if (ptr->is_null())
             {
-                // check if the reference token is a valid array index, that is
-                // a nonempty sequence of digits without a leading '0'
-                // (cf. RFC 6901, Sect. 4); tokens that could never be a valid
-                // array index (such as "01" or "") are treated as object keys
-                const bool nums = !reference_token.empty()
-                                  && (reference_token.size() == 1 || reference_token[0] != '0')
-                                  && std::all_of(reference_token.begin(), reference_token.end(),
-                                                 [](const unsigned char x)
+                // check if the reference token is a number
+                const bool nums =
+                    std::all_of(reference_token.begin(), reference_token.end(),
+                                [](const unsigned char x)
                 {
                     return std::isdigit(x);
                 });
 
-                // change value to an array for array indices or "-" or to object otherwise
+                // change value to an array for numbers or "-" or to object otherwise
                 *ptr = (nums || reference_token == "-")
                        ? detail::value_t::array
                        : detail::value_t::object;

tests/src/unit-json_pointer.cpp

@@ -438,72 +438,6 @@ TEST_CASE("JSON pointers")
         }
     }
 
-    SECTION("creating intermediate levels")
-    {
-        SECTION("tokens that are valid array indices create arrays")
-        {
-            json j;
-            j["/0"_json_pointer] = 1;
-            CHECK(j == json({1}));
-
-            json j2;
-            j2["/2"_json_pointer] = 1;
-            CHECK(j2 == json({nullptr, nullptr, 1}));
-
-            json j3;
-            j3["/-"_json_pointer] = 1;
-            CHECK(j3 == json({1}));
-
-            json j4;
-            j4["/foo/0/0"_json_pointer] = 1;
-            CHECK(j4 == json({{"foo", {{1}}}}));
-        }
-
-        SECTION("tokens that are no valid array indices create objects")
-        {
-            json j;
-            j["/one"_json_pointer] = 1;
-            CHECK(j == json({{"one", 1}}));
-
-            // leading '0' can never be a valid array index (RFC 6901, Sect. 4)
-            json j2;
-            j2["/01"_json_pointer] = 1;
-            CHECK(j2 == json({{"01", 1}}));
-
-            // the empty token is a valid object key, but no valid array index
-            json j3;
-            j3["/"_json_pointer] = 1;
-            CHECK(j3 == json({{"", 1}}));
-        }
-
-        SECTION("creating a level yields the same result as reusing it (#5357)")
-        {
-            json j;
-            j["/a/b/01/d"_json_pointer] = "value";
-
-            json j_init = json::object();
-            j_init["/a/b"_json_pointer] = json::object();
-            j_init["/a/b/01/d"_json_pointer] = "value";
-
-            const json expected = json::parse(R"({"a":{"b":{"01":{"d":"value"}}}})");
-            CHECK(j == expected);
-            CHECK(j_init == expected);
-
-            // unflatten uses the same key
-            const json flat = {{"/a/b/01/d", "value"}};
-            CHECK(flat.unflatten() == expected);
-        }
-
-        SECTION("existing arrays still reject invalid indices")
-        {
-            json j = {1, 2, 3};
-            CHECK_THROWS_WITH_AS(j["/01"_json_pointer],
-                                 "[json.exception.parse_error.106] parse error: array index '01' must not begin with '0'", json::parse_error&);
-            CHECK_THROWS_WITH_AS(j.at("/01"_json_pointer),
-                                 "[json.exception.parse_error.106] parse error: array index '01' must not begin with '0'", json::parse_error&);
-        }
-    }
-
     SECTION("flatten")
     {
         json j =

tools/generate_natvis/nlohmann_json.natvis.j2

@@ -36,5 +36,31 @@
         </Expand>
     </Type>
 
+    <!-- Fallback for when the basic_json entry above does not match: json_default_base is the (empty) default
+         base class of basic_json, and base class visualizers are inherited by derived types and evaluated
+         against the derived object, so m_data is accessible here. The class lives in {{ ns }} after
+         3.12.0 (#5238) and in {{ ns }}::detail up to 3.12.0, so both names are listed. -->
+{% for default_base in ['json_default_base', 'detail::json_default_base'] %}
+    <Type Name="{{ ns }}::{{ default_base }}">
+        <DisplayString Condition="m_data.m_type == {{ ns }}::detail::value_t::null">null</DisplayString>
+        <DisplayString Condition="m_data.m_type == {{ ns }}::detail::value_t::object">{*(m_data.m_value.object)}</DisplayString>
+        <DisplayString Condition="m_data.m_type == {{ ns }}::detail::value_t::array">{*(m_data.m_value.array)}</DisplayString>
+        <DisplayString Condition="m_data.m_type == {{ ns }}::detail::value_t::string">{*(m_data.m_value.string)}</DisplayString>
+        <DisplayString Condition="m_data.m_type == {{ ns }}::detail::value_t::boolean">{m_data.m_value.boolean}</DisplayString>
+        <DisplayString Condition="m_data.m_type == {{ ns }}::detail::value_t::number_integer">{m_data.m_value.number_integer}</DisplayString>
+        <DisplayString Condition="m_data.m_type == {{ ns }}::detail::value_t::number_unsigned">{m_data.m_value.number_unsigned}</DisplayString>
+        <DisplayString Condition="m_data.m_type == {{ ns }}::detail::value_t::number_float">{m_data.m_value.number_float}</DisplayString>
+        <DisplayString Condition="m_data.m_type == {{ ns }}::detail::value_t::discarded">discarded</DisplayString>
+        <Expand>
+            <ExpandedItem Condition="m_data.m_type == {{ ns }}::detail::value_t::object">
+                *(m_data.m_value.object),view(simple)
+            </ExpandedItem>
+            <ExpandedItem Condition="m_data.m_type == {{ ns }}::detail::value_t::array">
+                *(m_data.m_value.array),view(simple)
+            </ExpandedItem>
+        </Expand>
+    </Type>
+
+{% endfor %}
 {% endfor %}
 </AutoVisualizer>