Fix the red CI on develop (json_view pointer tokens, bson, from_json tests, Infer, IWYU) (#5942)

* json_view: pointer tokens that cannot be array indices create objects

editable_document::set() chose an array for a null parent whenever the
token consisted of digits, so "01" threw parse_error.106 and the empty
token threw, while basic_json::operator[](json_pointer) has created an
object for such tokens since #5358. This broke
unit-json_view_edit_values on develop. Use the same RFC 6901 array index
test as basic_json.

Also re-indent the unflatten test that the astyle check flagged.

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

* Fix the other red jobs on develop

- unit-bson: initialize recorder::events in its declaration (-Weffc++)
- unit-json_view_from_json: suppress -Wexit-time-destructors for the
  serialize-enum tables and -Wfloat-equal for same()
- unit-pointer_access: @infer-ignore NULLPTR_DEREFERENCE for the
  dereferences after get_ptr() that Infer reports
- json_view.hpp: IWYU no_include for the detail headers that the view
  code uses through nlohmann/json.hpp

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

* Fix GCC warnings in the json_view from_json test

GCC (-Weffc++, -Wfloat-equal) rejected unit-json_view_from_json.cpp
(ci_test_standards_gcc (20)): initialize the members of shape and
with_names, and suppress -Wfloat-equal for GCC like for clang.

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

---------

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

include/nlohmann/json_view.hpp

@@ -54,9 +54,11 @@
 // IWYU pragma: no_include <version>
 // IWYU pragma: no_include "nlohmann/detail/abi_config.hpp"
 // IWYU pragma: no_include "nlohmann/detail/abi_macros.hpp"
+// IWYU pragma: no_include "nlohmann/detail/conversions/from_json.hpp"
 // IWYU pragma: no_include "nlohmann/detail/input/input_adapters.hpp"
 // IWYU pragma: no_include "nlohmann/detail/json_pointer.hpp"
 // IWYU pragma: no_include "nlohmann/detail/meta/cpp_future.hpp"
+// IWYU pragma: no_include "nlohmann/detail/meta/type_traits.hpp"
 // IWYU pragma: no_include "nlohmann/detail/string_concat.hpp"
 // IWYU pragma: no_include "nlohmann/detail/value_t.hpp"
 // IWYU pragma: no_include "nlohmann/json.hpp"
@@ -1313,7 +1315,7 @@ class basic_json_document
     /// member is set (added if missing), an array element assigned, and "-"
     /// or the size of the array appends. A null parent becomes what
     /// basic_json's operator[](json_pointer) makes of it: an array for "-"
-    /// and for digits (padded with nulls up to the index), an object otherwise.
+    /// and for array indices (padded with nulls up to the index), an object otherwise.
     template<typename V>
     view_type set(const json_pointer& ptr, V&& value)
     {
@@ -1329,7 +1331,11 @@ class basic_json_document
             {
                 return push_back(parent, std::forward<V>(value));
             }
-            const bool digits = std::all_of(token.begin(), token.end(), [](const char c)
+            // (a token that cannot be an array index, such as "01" or "", names an
+            // object member, as in basic_json)
+            const bool digits = !token.empty()
+                                && (token.size() == 1 || token[0] != '0')
+                                && std::all_of(token.begin(), token.end(), [](const char c)
             {
                 return c >= '0' && c <= '9';
             });

single_include/nlohmann/json_view.hpp

@@ -54,9 +54,11 @@
 // IWYU pragma: no_include <version>
 // IWYU pragma: no_include "nlohmann/detail/abi_config.hpp"
 // IWYU pragma: no_include "nlohmann/detail/abi_macros.hpp"
+// IWYU pragma: no_include "nlohmann/detail/conversions/from_json.hpp"
 // IWYU pragma: no_include "nlohmann/detail/input/input_adapters.hpp"
 // IWYU pragma: no_include "nlohmann/detail/json_pointer.hpp"
 // IWYU pragma: no_include "nlohmann/detail/meta/cpp_future.hpp"
+// IWYU pragma: no_include "nlohmann/detail/meta/type_traits.hpp"
 // IWYU pragma: no_include "nlohmann/detail/string_concat.hpp"
 // IWYU pragma: no_include "nlohmann/detail/value_t.hpp"
 // IWYU pragma: no_include "nlohmann/json.hpp"
@@ -9078,7 +9080,7 @@ class basic_json_document
     /// member is set (added if missing), an array element assigned, and "-"
     /// or the size of the array appends. A null parent becomes what
     /// basic_json's operator[](json_pointer) makes of it: an array for "-"
-    /// and for digits (padded with nulls up to the index), an object otherwise.
+    /// and for array indices (padded with nulls up to the index), an object otherwise.
     template<typename V>
     view_type set(const json_pointer& ptr, V&& value)
     {
@@ -9094,7 +9096,11 @@ class basic_json_document
             {
                 return push_back(parent, std::forward<V>(value));
             }
-            const bool digits = std::all_of(token.begin(), token.end(), [](const char c)
+            // (a token that cannot be an array index, such as "01" or "", names an
+            // object member, as in basic_json)
+            const bool digits = !token.empty()
+                                && (token.size() == 1 || token[0] != '0')
+                                && std::all_of(token.begin(), token.end(), [](const char c)
             {
                 return c >= '0' && c <= '9';
             });

tests/src/unit-bson.cpp

@@ -1311,7 +1311,7 @@ TEST_CASE("BSON declared document size bounds the content")
     // records the events that a SAX parser receives
     struct recorder : nlohmann::json_sax<json>
     {
-        std::string events;
+        std::string events{};
 
         bool null() override
         {

tests/src/unit-json_pointer.cpp

@@ -1122,17 +1122,17 @@ TEST_CASE("flatten of structured values")
 
         // the same for other keys that are not valid array indices
         CHECK_THROWS_WITH_AS(json({{"/a/0", 1}, {"/a/1a", 2}}).unflatten(),
-                             "[json.exception.out_of_range.404] unresolved reference token '1a'", json::out_of_range&);
+        "[json.exception.out_of_range.404] unresolved reference token '1a'", json::out_of_range&);
         CHECK_THROWS_WITH_AS(json({{"/a/0", 1}, {"/a/-", 2}}).unflatten(),
-                             "[json.exception.out_of_range.404] unresolved reference token '-'", json::out_of_range&);
+        "[json.exception.out_of_range.404] unresolved reference token '-'", json::out_of_range&);
     }
 
     SECTION("unflatten with the empty token among array indices")
     {
         CHECK_THROWS_WITH_AS(json({{"/a/0", 1}, {"/a/", 2}}).unflatten(),
-                             "[json.exception.out_of_range.404] unresolved reference token ''", json::out_of_range&);
+        "[json.exception.out_of_range.404] unresolved reference token ''", json::out_of_range&);
         CHECK_THROWS_WITH_AS(json({{"/a/0", 1}, {"/a/1", 2}, {"/a/", 3}}).unflatten(),
-                             "[json.exception.out_of_range.404] unresolved reference token ''", json::out_of_range&);
+        "[json.exception.out_of_range.404] unresolved reference token ''", json::out_of_range&);
 
         // without an index "0", the empty token is an ordinary object key
         CHECK(json({{"/a/", 2}}).unflatten() == json({{"a", {{"", 2}}}}));

tests/src/unit-json_view_from_json.cpp

@@ -41,6 +41,13 @@ using nlohmann::ordered_json_document;
     #include <optional>
 #endif
 
+// NLOHMANN_JSON_SERIALIZE_ENUM uses a static std::pair; same() compares floating-point values on purpose
+DOCTEST_CLANG_SUPPRESS_WARNING_PUSH
+DOCTEST_CLANG_SUPPRESS_WARNING("-Wexit-time-destructors")
+DOCTEST_CLANG_SUPPRESS_WARNING("-Wfloat-equal")
+DOCTEST_GCC_SUPPRESS_WARNING_PUSH
+DOCTEST_GCC_SUPPRESS_WARNING("-Wfloat-equal")
+
 // The from_json() functions of the NLOHMANN_DEFINE_TYPE_* and
 // NLOHMANN_JSON_SERIALIZE_ENUM macros read views directly; other from_json()
 // functions get the value of materialize().
@@ -61,10 +68,11 @@ struct point
 
 struct shape
 {
-    std::string name;
+    // initialized for GCC -Weffc++
-    std::vector<point> points;
+    std::string name{};
-    point center;
+    std::vector<point> points{};
-    std::map<std::string, point> named;
+    point center{};
+    std::map<std::string, point> named{};
     NLOHMANN_DEFINE_TYPE_INTRUSIVE(shape, name, points, center, named)
 };
 
@@ -79,7 +87,7 @@ NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE_WITH_DEFAULT(with_defaults, a, b, c)
 struct with_names
 {
     int value = 0;
-    std::string text;
+    std::string text{};  // initialized for GCC -Weffc++
 };
 NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE_WITH_NAMES(with_names, "Value", value, "Text", text)
 
@@ -447,3 +455,6 @@ TEST_CASE("json_view from_json")
     }
 #endif
 }
+
+DOCTEST_CLANG_SUPPRESS_WARNING_POP
+DOCTEST_GCC_SUPPRESS_WARNING_POP

tests/src/unit-pointer_access.cpp

@@ -141,6 +141,7 @@ TEST_CASE("pointer access")
         // check if pointers are returned correctly
         const test_type* p1 = value.get_ptr<test_type*>();
         CHECK(p1 == value.get_ptr<test_type*>());
+        // @infer-ignore NULLPTR_DEREFERENCE
         CHECK(*p1 == value.get<test_type>());
 
         const test_type* p2 = value.get_ptr<const test_type*>();
@@ -170,6 +171,7 @@ TEST_CASE("pointer access")
         // check if pointers are returned correctly
         test_type* p1 = value.get_ptr<test_type*>();
         CHECK(p1 == value.get_ptr<test_type*>());
+        // @infer-ignore NULLPTR_DEREFERENCE
         CHECK(*p1 == value.get<test_type>());
 
         const test_type* p2 = value.get_ptr<const test_type*>();
@@ -199,6 +201,7 @@ TEST_CASE("pointer access")
         // check if pointers are returned correctly
         const test_type* p1 = value.get_ptr<test_type*>();
         CHECK(p1 == value.get_ptr<test_type*>());
+        // @infer-ignore NULLPTR_DEREFERENCE
         CHECK(*p1 == value.get<test_type>());
 
         const test_type* p2 = value.get_ptr<const test_type*>();
@@ -232,6 +235,7 @@ TEST_CASE("pointer access")
 
         const test_type* p2 = value.get_ptr<const test_type*>();
         CHECK(p2 == value.get_ptr<const test_type*>());
+        // @infer-ignore NULLPTR_DEREFERENCE
         CHECK(*p2 == value.get<test_type>());
 
         const test_type* const p3 = value.get_ptr<const test_type* const>();
@@ -257,6 +261,7 @@ TEST_CASE("pointer access")
         // check if pointers are returned correctly
         const test_type* p1 = value.get_ptr<test_type*>();
         CHECK(p1 == value.get_ptr<test_type*>());
+        // @infer-ignore NULLPTR_DEREFERENCE
         CHECK(*p1 == value.get<test_type>());
 
         const test_type* p2 = value.get_ptr<const test_type*>();