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Author	SHA1	Message	Date
Niels Lohmann	6a852ab96d	Split the json_view feature page into sub-pages (#6018 ) * Split the json_view feature page into sub-pages The single features/json_view.md page grew to ~600 lines covering eight topics. Split it into features/json_view/ with an overview page and pages for ownership and lifetime, differences from basic_json, reading values, generic code, editing, and images. The new differences page collects what was spread over several sections ("What is the same", "What is different", "Duplicate keys", and notes in the conversion and serialization sections) under one summary table, and adds the parts of the basic_json interface a view does not have. The other pages now link to it instead of restating the rules. Internal links across the documentation point to the new pages. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Docs: fix stale comments and trim repeated text in json_view pages - fig-jsonview.js/.css: point the header comments at the new pages - reading.md: views' strings are valid as long as the document (and a borrowed source text), as lifetime.md says - reading.md, generic_code.md: link to differences.md instead of restating the member-order and repeated-key rules - differences.md: drop the third mention of ordering comparisons, name rbegin()/rend() in the iterator row - exceptions.md: link editable documents to editing.md Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-11-09 08:12:00 +01:00
Niels Lohmann	a49242f088	Docs: reading and writing files; patch_inplace() is not atomic (#6017 )	2026-11-04 17:46:20 +01:00
Niels LohmannandClaude Opus 5.5	bfe69c73c2	json_view: get<T>() of a boolean throws for the exact number types, as basic_json does (#5992 ) * json_view: get<T>() of a boolean throws for number_integer_t, number_unsigned_t and number_float_t like basic_json (#5988) basic_json::get<T>() of a boolean throws type_error.302 for exactly number_integer_t, number_unsigned_t and number_float_t (dedicated from_json() overloads) and gives 0/1 for every other arithmetic type. The view returned 0/1 for all of them, contradicting its documentation. The view now throws the same exception (same message, with path/bytes decoration) for these three types. basic_json is unchanged; its behavior is documented and pinned by a test. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * tests: skip throwing json_view bool get<T>() combinations without exceptions (#5988) check_boolean_get_parity() called get<T>() for number_integer_t, number_unsigned_t and number_float_t in its JSON_NOEXCEPTION branch, but a boolean throws type_error.302 for exactly these types, so JSON_THROW aborted test-json_view_cpp11/cpp17 in ci_test_noexceptions. Skip these combinations there; the throwing checks stay in the exceptions-enabled build. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01N5NasAgbDGG28MqXjQvLqp Signed-off-by: Claude <noreply@anthropic.com> * Expect the byte range of the root in the json_view boolean get<T>() test With JSON_DIAGNOSTIC_POSITIONS, the type_error.302 message starts with "(bytes 0-4)"; build the expected text with json_view_test::message(), as the other tests of the root value do. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01N5NasAgbDGG28MqXjQvLqp Signed-off-by: Claude <noreply@anthropic.com> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me> Signed-off-by: Claude <noreply@anthropic.com> Co-authored-by: Claude <noreply@anthropic.com>	2026-11-02 17:48:43 +01:00
Niels LohmannandClaude	494a74c242	insert(): strong guarantee for single elements, basic guarantee for the rest (#5996 ) * Make basic_json::insert() provide its documented strong exception guarantee (#5986) A failed allocation while the new elements were copied left the value changed, and with JSON_DIAGNOSTICS stale parent pointers behind. The extra work now happens almost only on the failure path: - Array insert(pos, cnt, val) and insert(pos, first, last) append the copies at the end and rotate them into place. If a copy throws, the appended elements are erased again (noexcept) and the parents are set. Moving a basic_json cannot throw, so reallocation is safe. This is no slower than vector::insert (faster for numbers), needs no temporary array, and keeps the elements that libstdc++ lost on reallocation. - Array insert(pos, val) copies a non-scalar value first and inserts it by move, except at the end, where vector::insert is strong. Scalars keep the direct path. - The object range insert(first, last) into an empty object uses the container's own range insertion and clears the object on an exception. Into a non-empty object it inserts member by member and logs one bit per source member (a new member is detected by the size change; no allocation for the first 256 members); on an exception the members added are erased by walking the source range. No assumption that key_type is string_t. - The parents are set when a failed insertion is undone. The regression test fails every allocation of every insert() overload in turn, for json and ordered_json, and checks the value and its parents. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Fix clang-tidy and -Wnrvo findings in insert rollback helpers Declare the rollback helpers non-movable, replace the nested conditional and C array in object_insert_rollback, silence the intentional copy in the allocator test, and avoid the missed NRVO in the test factory lambda. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01N5NasAgbDGG28MqXjQvLqp Signed-off-by: Claude <noreply@anthropic.com> * insert(): strong guarantee for single elements, basic for the rest Rework of the previous two commits, following the discussion in #5996: the standard containers give the strong guarantee only for a single element (std::vector: at the end, or if the exception does not come from copying T; std::map: single-element insert), and copying a basic_json allocates. Rebuilding a rollback for the count, range and object-range overloads on top of array_t/object_t made the code verbose and slower. - insert(pos, const basic_json&): at end() forward as before (the standard covers it); elsewhere copy first and insert by move, as libstdc++ does internally (libc++ shifts the tail before copying). - insert_iterator() and object insert(first, last) set the parents in a scope guard, so a failed insertion leaves a valid value with JSON_DIAGNOSTICS too (the next assert_invariant() aborted before). - Docs: strong guarantee for (1), basic guarantee for (2)-(5); the argument checks throw before anything is changed. - Test: allocation-failure sweep checks the strong guarantee for (1) and validity, type and parents for the other overloads. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * insert(): document the exception safety of overloads 2 to 5 once The four basic-guarantee statements were identical up to array/object. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * insert(): simplify the wording of the basic guarantee Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me> Signed-off-by: Claude <noreply@anthropic.com> Co-authored-by: Claude <noreply@anthropic.com>	2026-11-02 17:48:29 +01:00
Niels Lohmann	2aecd86b37	Document the contract of object keys passed to json_sax::key and key callbacks (#5956 ) * Document the contract of object keys passed to json_sax::key and key callbacks Describe what the name passed to json_sax::key and to a parser callback for parse_event_t::key holds when parsing JSON text: escapes are decoded to UTF-8, different spellings of a name yield identical strings, the name is validated before the call (invalid escapes or UTF-8 give a parse error and no key event), no normalization or case conversion is applied, the event precedes the ':' check, and duplicate names are reported once per occurrence. Also note that sax_parse passes binary-format keys unchanged. See discussion #5955. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Add a test for the object key contract and correct the BON8 note Pin the guarantees documented for json_sax::key and the key event of parser callbacks: decoded names, validation before delivery, delivery before the colon, one event per repeated name, and the binary formats. BON8 rejects ill-formed UTF-8 in a name even with sax_parse, so the note no longer lists it with the formats that pass bytes through. See discussion #5955. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Fix the GCC build of the object key contract test GCC 11 in C++11 mode rejects a default argument on a lambda parameter (-Wc++14-extensions) and ignores a static_cast<void> on the warn_unused_result of parse(). Pass the input format explicitly and bind the parse result to a variable. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Add version history for the object key contract Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-29 07:37:33 +01:00
Niels Lohmann	091c10d4a5	Fix self-aliasing in json_pointer::operator/= and patch_inplace (#5936 ) * Fix self-aliasing in json_pointer::operator/= and patch_inplace json_pointer::operator/=(const json_pointer&) passed iterators into its own token vector to insert() when a pointer was appended to itself (p /= p), which is undefined behavior; libstdc++ produced "/a/b//" for "/a/b". The pointer now appends a copy in that case. basic_json::patch_inplace iterated the patch while changing this, so j.patch_inplace(j) read freed memory. It now applies a copy of the patch when the patch is the value itself. A patch stored inside the value remains undefined behavior and is documented as such; copying the patch unconditionally would double the time of a large patch. Signed-off-by: Niels Lohmann <mail@nlohmann.me> Fix JSON_DIAGNOSTICS test crash and clang-tidy hit in patch_inplace self-aliasing The spare-capacity test reallocated non-empty elements through get_ref(), which leaves stale parent pointers under JSON_DIAGNOSTICS; reserve while the array is empty instead. Suppress performance-unnecessary-copy-initialization for the copy that is needed because this is modified. Signed-off-by: Niels Lohmann <mail@nlohmann.me> Detect a patch stored inside the patched value with JSON_DIAGNOSTICS patch_inplace applied a copy only when the patch was the value itself. With JSON_DIAGNOSTICS the parent pointers make it cheap to also detect a patch nested inside the value, so that case is handled the same way. Without diagnostics it stays documented undefined behavior. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Silence misc-const-correctness for patch_aliases_this Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Fix clang-tidy findings in the operator/= self-append test Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-28 20:23:55 +01:00
Niels Lohmann	eb8f675bc9	docs: explain signed zero in the diff() round-trip exceptions (#5944 ) Spell out that numbers comparing equal produce no operation even if one is zero and the other negative zero, in diff.md and features/json_patch.md. Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-27 17:16:08 +01:00
Niels Lohmann	78a0687147	Strong exception guarantee for operator[](json_pointer) (#5940 ) * Keep the value unchanged when operator[] with a JSON pointer throws The non-const operator[](json_pointer) is documented with strong exception safety, but get_unchecked created intermediate values while walking the pointer and kept them when a later reference token failed, e.g. json j; j["/a/99999999999999999999999"_json_pointer] threw 404 and left {"a":[]}; padding an existing array or appending with "-" behaved alike, and so did std::length_error/std::bad_alloc from a huge index. get_unchecked now only walks existing values up to the last reference token. The last token's key insertion or array growth is strongly exception safe by itself. Any other change goes through get_unchecked_create, which records the one change it makes to an existing value (null converted, key inserted, array grown) in a RAII guard and reverts it if a later step throws; everything else it creates lies below that change. The guard needs no try/catch, so JSON_NOEXCEPTION builds are unaffected. Successful calls create the same values as before. Docs: state the guarantee in the exceptions list and version history of operator[], fix the complexity of the pointer overloads of operator[] and at, and warn that padding arrays up to an untrusted index allocates memory proportional to the index (operator[].md, untrusted_input.md). Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Make the strongly exception-safe pointer operator[] faster than before The previous commit made get_unchecked strongly exception safe but slower with GCC 16 when it creates values (up to +6 % instructions for appending with "-"). This restructures it so that no benchmark row is slower than before the strong guarantee, with GCC 16, Clang 22 and Apple Clang. - get_unchecked walks existing values in one loop that inserts nothing. The last reference token is resolved in that walk: "-" appends with emplace_back(), an index grows the array with operator[], and a missing key is inserted with emplace_hint() at the position the walk's lower_bound() found, so the key is searched once. - With std::less<string_t> or std::less<> as comparator, the walk checks the key at the lower bound for equality instead of equivalence, which is the same for these comparators and cheaper. - get_unchecked_create (not inlined) handles all other changes. Its guard swaps a null value with a fresh null value instead of copying it and reverts the change in a non-inlined function, so a successful call pays one compare for it. As every null value converted afterwards is a fresh one, it is converted in place instead of assigning a new array or object. - Keys are added to new objects with emplace(), which also replaces the basic_json::operator[] call for ordered_json. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Fix rollback of pointer operator[] for unusual object and string types Follow-up to the strong exception guarantee of the non-const operator[](json_pointer): - get_unchecked_create assumed that emplace() always inserts the key that the walk did not find. For object types whose lookup and emplace() disagree (e.g. a copied fifo_map), nothing was inserted, the rollback erased the existing member, and the walk continued with a value of the wrong type (assertion, type_error.305, or a crash). It now checks the result of emplace(), arms the rollback only if a key was inserted, and otherwise continues the walk with the member found, as basic_json's operator[] does: such pointers throw out_of_range.404 and leave the value unchanged, as before the strong guarantee. - The rollback erased the inserted key by key, which converts string_t to object_t::key_type and may allocate inside a noexcept function (std::terminate on bad_alloc with custom key types). It now erases by the iterator emplace() returned, and shrinks a grown array with erase() at the end instead of resize(). The documentation states the remaining requirement for custom template parameters. - Creating values no longer calls string_t::begin(), so the non-const operator[](json_pointer) compiles with string types that lack it (as the alternative string type of the tests). - Correct the @throw lists of get_unchecked and get_unchecked_create. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Address review comments on operator[](json_pointer) rollback - undo() shrinks the array with resize() instead of erase() - comments say what "will be" done in get_unchecked_create - tests: avoid a clang-tidy performance-unnecessary-copy-initialization hit (unit-alt-string) and the word "access" in section names, which Flawfinder flags as race/access Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Let the pointer rollback guard call undo() unconditionally The check in the destructor and JSON_HEDLEY_NEVER_INLINE on undo() made no measurable difference: instruction counts of j[ptr] are identical with GCC 13 -O3 and within 0.4 % with clang, timings are within noise. Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-27 17:15:55 +01:00
Niels Lohmann	a47170346a	docs: new design for the documentation site (#5934 ) * docs: new design for the documentation site Apply the brand to the Material for MkDocs site: Inter and JetBrains Mono served by the site (upright and real italic), brand colours, blue header band with the syntax pattern, wordmark in the header, new home page (hero, cards, animated feature tour), 404 page, polish for tabs, search, footer, focus rings, tables and code blocks, and theme features (code copy, previous/next footer, TOC follow, search suggestions). Draw the number railroad diagram, the parser callback events and the iterator illustrations as inline SVGs that follow the light and dark scheme. The generator scripts are in docs/mkdocs/scripts/figures; the feature slideshow (json-light.svg, json-dark.svg, replacing json.gif on the home page) is built by docs/mkdocs/scripts/slideshow. Decision nodes in five flowcharts become hexagons, which need far less room. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * docs: add figures, table captions and a macro chooser - Figures with numbered captions: SAX stepper, json_view layout and edit stepper, exception map, JSON pointer and patch walkers, QA pipeline, scaling and binary size charts, roadmap lanes, release timeline, integration decision tree and namespace builder - Table captions (nj-table-caption) on 9 pages - Compile times: modules and PCH charts, filesystem section, re-measured Figure 1, links between features/modules.md and compile_times.md - Interactive macro chooser for features/arbitrary_types.md - Link check: exclude URLs that answer the plugin with 400/401/419 or are dead (customers.md) Signed-off-by: Niels Lohmann <mail@nlohmann.me> * docs: macro chooser generates adl_serializer for non-default-constructible types Signed-off-by: Niels Lohmann <mail@nlohmann.me> * docs: cross-link concept pages and API pages in See also sections Add See also links in both directions between the concept pages (features, home, integration) and the API pages, write API links in code font, give every entry a comment after a dash, and show the callback event figure on the parser callbacks page. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * docs: address review comments on the new design - Home: add a "Latest release" button - Sponsors: update the list and group it by tier - Features: list all feature pages on the index page - Releases: add highlights per release, link the 4.0 roadmap, add the first commit to the timeline - Exceptions: prefix all example messages with the exception name - API: no code font for format names in the See also links of the to_/from_ pages - Merge Patch: show the document before, the patch, and the result - Replace "--" with typographic dashes, mark external links with an icon, center Mermaid diagrams Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-27 07:41:42 +01:00
Niels Lohmann	24078c862d	docs: fix BON8 documentation gaps found in the format review (#5932 ) * docs: fix BON8 documentation gaps found in the format review Verified each claim with small C++ probes before writing it. - index.md: BON8 serialization is also incomplete for invalid UTF-8. - bon8.md: document duplicate keys (last wins), the error ids for malformed input incl. 0xF5..0xF7 + 0x80..0xBF, exact string termination wording, wide integers and discarded values in the unsupported list, and title two untitled admonitions. - exceptions.md: to_bon8 in type_error.316, BON8 in parse_error.112 (with example) and .113, wide integers in out_of_range.407. - binary_values.md: bytes 0..39 take one byte in BON8. - from_bon8.md: note on strict UTF-8 and duplicate keys. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Address review of the BON8 documentation Restore the correct statement that marker bytes cannot begin a UTF-8 character (0x80..0xBF occur in valid UTF-8 as continuation bytes), and reword two sentences. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * docs: drop the discarded-value remark from the BON8 page Discarded values are not mentioned on the individual format pages. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * docs: do not list invalid UTF-8 strings as a BON8 serialization gap JSON text must be valid UTF-8, and to_bon8 rejects ill-formed strings by design (type_error.316), as documented on the BON8 page. Restore the original cell and realign the table. Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-26 18:25:46 +01:00
Niels Lohmann	60107eda3f	Read BJData ND-arrays of float16, restrict ND-array char to 0..127, correct BJData docs (#5931 ) * Read ND-arrays of half floats and enforce the char limit in ND-arrays BJData N-dimensional arrays with element type 'h' (float16) failed to read with a misleading parse_error.112, because the reader's dtype name table lacked 'h'. It now maps to "half", the JData name. The writer still does not pack "half"; such an object is written as a plain object and reads back equal. BJData limits 'C' (char) to 0..127 in Draft 2 and Draft 3, and the 1-D reader enforces this, but ND-arrays with _ArrayType_ "char" wrote values up to 255 as 'C' elements and read them back without a check. The writer now only packs values in 0..127 (others fall back to a plain object that round-trips), and the reader rejects 'C' elements above 127 with parse_error.113 like the 1-D reader. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * docs: correct and complete the BJData documentation Verify the BJData chapter against the library and the Draft 2/3/4 specifications and fix what did not match: - bjdata.md: correct the list of unused markers (N, not Z), the ND-array example (3x2, not 2x3), the conditions under which an object is packed as an ND-array (exactly three keys, row vectors, float-only elements for single/double, char 0..127, byte only in Draft 3), the binary table row and notes (which flag/draft combinations write [$B), the "$" type restriction (Draft 3, Z is excluded too), the H marker in the deserialization table, and the claim of a complete deserialization mapping. Document the supported drafts, that Draft 4 (SoA containers, extension type E) and column-major ND-arrays are rejected, ND-arrays of half floats, duplicate object keys, and link the Draft 3 specifications instead of master. - Add an API page for basic_json::bjdata_version_t with an example, and link it from the nav, the API index and to_bjdata. - Update binary_formats/index.md and binary_values.md, which still claimed that BJData has no binary type, and fix a wrong byte comment there. - Document parse_error.115 and the out_of_range.408 cases for from_bjdata, the precise other_error.502 condition for to_bjdata, and reword the note on truncated unsigned integers in exceptions.md (only ND-array elements were truncated before 3.13.0). Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Regenerate single_include and apply astyle Result of make amalgamate (including make pretty) for the preceding changes. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Address review of the BJData documentation The $ type restriction exists since Draft 2 (Draft 3 added B), $ requires a count, ND char above 127 is rejected on read, and the new API page is listed in alphabetical order in the nav. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * docs: format tables, use the Oxford comma Reformat the tables changed by this PR (BJData serialization and deserialization mappings, completeness and binary-value tables) so all rows are aligned, and add the Oxford comma to lists of three or more items in the added text. Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-26 18:25:46 +01:00
Niels Lohmann	dc768a7d5d	Fix BSON binary subtype 0x02 and check the declared document size earlier (#5930 ) * Write and read the inner length of BSON binary subtype 0x02 The BSON specification defines the payload of the "binary (old)" subtype 0x02 as an int32 followed by that many bytes. to_bson wrote the plain payload instead, so decoders such as pymongo and libbson-based readers rejected the bytes, and from_bson returned the inner length as part of the payload (documented as lenient behavior in gh-5333). The writer now emits the outer length (payload + 4), the subtype, the inner int32 holding the payload size, and the payload. The reader requires an outer length of at least 4 and an inner length equal to the outer length minus 4 (the cases the bson-corpus lists as decode errors), reports parse error 112 otherwise, and returns only the payload. Both directions change together so that the round trip keeps working. The single-reservation fast path for scalar entries declines subtype 0x02 because it has no room for the inner length. This is a deliberate exception to the opt-in rule for behavior changes: the previous output was invalid BSON. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Check the declared BSON document size before reading its content The BSON reader compared a document's declared size with the number of bytes read only when it reached the terminator. The declared size never bounded the reads, so a SAX handler saw the keys and values of a document whose size was too small before parse error 112 was reported. The container frame now stores the position where the document ends according to its declared size. open_bson_document rejects a size below 5 (size prefix plus terminator) and an embedded document that does not end before the terminator of its enclosing document; the element loop rejects an element whose type byte leaves no room for the name terminator and the document terminator. The terminator check stays and still catches a declared size that is too large. No input that was accepted before is rejected now; documents with a wrong size are reported earlier, with fewer SAX events, a different byte position and, in three cases, a different message. The error id (parse_error.112) is unchanged and strict=false still does not skip the check. The tests that asserted the old messages and positions are updated, with the outer sizes of two inputs corrected so that they still exercise the embedded document. New tests cover the SAX events, a size below 5, and an embedded document that fits exactly. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Document BSON subtype 0x02, document size checks, and lenient reads Describe the inner length of binary subtype 0x02 that to_bson now writes and from_bson checks and removes. Add the document size checks (parse_error.112, not affected by strict=false) to bson.md and from_bson.md, and extend the list of lenient reads with the UUID and MD5 payload lengths (not checked), duplicate keys (last value wins), embedded NUL bytes in strings, and the ignored trailing bytes with strict=false. State that the members of an object are written in iteration order. Correct the statement that element names are never validated on read: they are checked and sanitized like string values by the error handler. Add the BSON message to the examples of out_of_range.415 and type_error.321, the subtype limit of 255 to the binary values page, CBOR to the formats that use byte_container_with_subtype, and fix a typo in the incomplete mapping box. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Regenerate single_include and apply astyle Result of make amalgamate (including make pretty) for the preceding changes. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Address review of the BSON documentation Describe exactly when a too small document size is detected and note that subtype 2 data written by earlier versions is not readable. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * docs: use the Oxford comma, drop discarded-value remarks Add the serial comma in a list added by this PR and remove the BSON example of type_error.321 (with the type_error.317 remark) so the docs do not mention discarded values for BSON; restore the original singular heading of that section. No tables were changed by this PR. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Fix -Weffc++ in the BSON recorder test and a clang-tidy use-auto hit Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Fix clang-tidy readability-redundant-member-init in BSON test Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-26 18:25:46 +01:00
Niels Lohmann	0c3570d44a	Validate the UBJSON/BJData container type marker for count 0; fix UBJSON docs (#5929 ) * Validate the optimized-container type marker for count 0 in UBJSON and BJData The '$' type marker of an optimized container was only checked when an element was read, so containers with count 0 accepted any marker: `[$x#i0`, `{$x#i0` and `[$E#i0` parsed as empty containers although a non-empty container with the same marker is rejected and the UBJSON specification requires a legal marker after '$'. get_ubjson_size_type() now checks the marker right after '$' against the allowed set (UBJSON: Z N T F i U I l L d D H C S [ {; BJData: B U i u I m l M L h d D C, with the existing exclusion of T F Z N S H [ {) and reports parse_error.112 "marker ... is not a permitted optimized array type". Input that was accepted and is now rejected: an optimized container with count 0 and an invalid '$' type marker. Valid input is unaffected. Two existing tests that used an invalid marker incidentally ("[$#" and a negative-count case) were adapted. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Correct and complete the UBJSON documentation Fix statements that disagree with the behavior (checked with probes): - `Z` is null; the unused marker is `N`. - `$` requires `#`; use_type with use_size=false throws other_error.502 only for non-empty arrays, objects and binary values. - NaN and infinity are written as IEEE 754 float64 and read back unchanged; the UBJSON specification encodes infinity as null. - `H` is documented (semantics, parse_error.115, out_of_range.406); the "complete mapping" claim is qualified. - use_type "same type" means same marker. - Long Z/T/F arrays lose only the `$` annotation; the `#` count and the element markers are kept. - from_ubjson lists the 112, 113, 115, 406 and 408 causes that occur for UBJSON, without the BJData-only ND-array wording. - Duplicate object keys keep the last value; the `$` type marker is validated even for count 0. - Smaller fixes: float32 row, "map" -> "object", https link, exception 110 strict case, to_ubjson history of discarded values. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Regenerate single_include and apply astyle Result of make amalgamate (including make pretty) for the preceding changes. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Address review of the UBJSON documentation Clarify that empty containers carry no $ annotation of their own and note that a counted N object is not supported. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * docs: format tables, use the Oxford comma, drop discarded-value remarks Reformat the two UBJSON mapping tables that this PR changed (uniform column widths, padded cells), use the serial comma in lists of three or more in the added text, and restore the original type_error.321 bullet in to_ubjson.md. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Fix narrowing of the optimized-container count in BJData and UBJSON tests Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-26 18:25:45 +01:00
Niels Lohmann	2bbe80c043	Document MessagePack ext types and fix related doc errors (#5928 ) * Document MessagePack ext types and fix related doc errors Add an "Extension types (ext, fixext)" section to the MessagePack page: ext/fixext are read as binary, the signed ext type is exposed as an unsigned subtype 0..255 (-1 reads as 255), Timestamp is not interpreted, subtypes are always written as ext/fixext, and subtypes above 255 throw out_of_range.415. Add the 0xC1 row to the deserialization table, note that duplicate keys keep the last value, and correct the NaN/Infinity explanation, the "31 bytes / 15 elements" wording, the ill-formed UTF-8 sentence, and the generic 0xC1-key error message. Add fixext16 and the unsigned subtype mapping to binary_t.md and binary_values.md, reword "maximum of the MessagePack ext type" in to_msgpack.md and exceptions.md, and mark MessagePack deserialization as incomplete (non-string keys) in the binary formats overview. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Address review of the MessagePack documentation Name parse_error.113 for a 0xC1 map key, move the duplicate-key sentence out of the ext section, and keep the 0xC1 row in marker order. Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-26 18:25:44 +01:00
Niels Lohmann	d5da84249f	Skip CBOR tags in front of map keys, validate indefinite text chunks, fix CBOR docs (#5927 ) * Skip CBOR tags in front of map keys and validate indefinite text chunks A tag in front of a text string map key was rejected with parse_error.113 even with cbor_tag_handler_t::ignore or store, although tags in front of values are handled. The tags are now skipped iteratively before the key is read; the handler error still rejects them. The chunks of an indefinite-length text string were concatenated before the single UTF-8 check, so a code point split over two chunks, or an invalid chunk, was accepted. RFC 8949, Section 3.2.3 requires every chunk to be valid on its own. With error_handler_t::strict, replace and ignore each chunk is now checked; keep is unchanged. The chunks are appended with append(ptr, len), so StringType needs nothing new. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * docs: correct and extend the CBOR documentation Fix the negative-integer rows (they used MessagePack boundaries), the number_integer range of the 0x1B row, and the half-precision entry in the list of unused types; correct the NaN history (0xF9 since 3.8.0) and the tagged-item wording (only the tag directly in front of a byte string is stored, and only in the 0xD8..0xDB form). Document that to_cbor is not RFC 8949 deterministic, that duplicate keys are accepted (last wins), tags in front of keys, per-chunk UTF-8 validation, the exceptions parse_error.113, out_of_range.406/408 of from_cbor, the pointer and C array input traps, the partially written output on exceptions, and the store/ignore results in the binary values example. Drop the claim that the CBOR reader needs StringType::append(const StringType&) and BinaryType::insert(pos, first, last). Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Regenerate single_include and apply astyle Result of make amalgamate (including make pretty) for the preceding changes. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Address review of the CBOR changes Cite RFC 8949 Section 5.3.1 for duplicate keys, describe the out_of_range.408 condition precisely, rewrap a long line, and update the stale get_string comment (per-chunk UTF-8 check). single_include regenerated. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * docs: drop discarded-value remarks Remove the mention that a discarded value cannot be serialized to CBOR (type_error.321) from the exception-safety and mapping sections. The integer table and all added prose already follow the table-format and Oxford-comma rules. Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-26 18:25:44 +01:00
Niels Lohmann	81d66291c5	Create objects for pointer tokens that cannot be array indices (#5358 ) * create objects for tokens that cannot be array indices (#5357) When operator[](json_pointer) traverses a level that does not exist yet, the null value is turned into an array or an object depending on the reference token. The check only tested whether all characters are digits, so tokens that can never be a valid array index selected an array and then failed: - "01" (and any other token with a leading '0') threw parse_error.106 - the empty token threw out_of_range.404 Both tokens are valid object keys, and both work when the level already exists as an object, so creating the level changed the outcome. Test the token against the RFC 6901, Sect. 4 grammar for array indices instead, so that such tokens create an object. This only affects pointers that threw before. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Clarify that the token 0 is a valid array index in operator[] docs The note described valid array indices as "a nonempty sequence of digits without a leading 0", which read literally excludes the token "0" itself, contradicting both the code and the /foo/0/0/0 example in the next sentence. Spell out the RFC 6901 grammar instead. Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-26 17:13:48 +01:00
Niels LohmannandClaude Sonnet 5.5	c712df0637	docs: make the diff() and patch() documentation accurate; add tests (#5939 ) * Throw out_of_range.411 for JSON Patch add into a null parent (#5917) Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01MKJf48vnGtTE25KscmjfaW Signed-off-by: Niels Lohmann <niels.lohmann@gmail.com> * docs: make the diff() and patch() documentation accurate; add tests Document the exceptions to the diff round-trip invariant (NaN, discarded values, number types), the path parameter, non-minimal patches, array and object operation order, the ordered_json fallback, binary values in serialized patches, the real complexity, duplicate member names in operations, test on missing paths, and the exact out_of_range.403 message. Add tests for these behaviors. Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <niels.lohmann@gmail.com> Signed-off-by: Niels Lohmann <mail@nlohmann.me> Co-authored-by: Claude Sonnet 5.5 <noreply@anthropic.com>	2026-10-26 17:12:05 +01:00
Niels Lohmann	7a10bf25d2	docs: state merge_patch complexity and RFC 7396 limitations; test non-object, discarded, binary cases (#5938 ) Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-26 17:11:55 +01:00
Niels Lohmann	c20b6eddf4	docs: correct JSON Pointer documentation and add tests (#5937 ) Fix inaccurate or missing statements about unflatten (third round-trip failure, empty token, typo), value (type_error.306 before pointer lookup), contains (pointer overload), parent_pointer and operator<< (bad_alloc), out_of_range.410 example, template parameter requirements (resize(n)), and document the URI fragment form and non-unique member names of RFC 6901. Add tests for the unflatten and value() cases. Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-26 17:11:46 +01:00
Niels LohmannandClaude Sonnet 5.5	d6431a9104	Throw out_of_range.411 for JSON Patch add into a null parent (#5917 ) (#5918 ) Claude-Session: https://claude.ai/code/session_01MKJf48vnGtTE25KscmjfaW Signed-off-by: Niels Lohmann <niels.lohmann@gmail.com> Co-authored-by: Claude Sonnet 5.5 <noreply@anthropic.com>	2026-10-26 17:11:25 +01:00
Niels Lohmann	330fbead59	Document clang-tidy exclusions, drop unneeded ones, and clean up doc examples (#5909 ) * Document clang-tidy exclusions and drop unneeded ones Re-enable every excluded check in a run of clang-tidy 22 over all tests and remove the seven that never fire (cert-err58-cpp, clang-analyzer-webkit.NoUncountedMemberChecker, cppcoreguidelines-virtual-class-destructor, google-readability-function-size, hicpp-function-size, hicpp-no-assembler, readability-function-size). Document the reason for every remaining exclusion at the top of the file. Exclude in advance the checks that only exist in clang-tidy 23 and are noise here (bugprone-signed-bitwise, -explicit-constructor, readability-trailing-comma, modernize-use-string-view), plus modernize-use-integer-sign-comparison, which needs C++20 std::cmp_less and flags deliberate casts. Signed-off-by: Niels Lohmann <mail@nlohmann.me> Fix clang-tidy findings in documentation examples and replace redundant aliases Apply clang-tidy fixes to the documentation examples: - performance-avoid-endl: std::endl -> '\n' - readability-qualified-auto: auto -> auto* / const auto* - performance-for-range-copy: copy -> const reference - google-readability-casting: C-style cast -> static_cast Replace redundant aliases (readability-redundant-qualified-alias) such as "using json = nlohmann::json;" with "using nlohmann::json;" in the documentation, README, examples, tests, and benchmarks. Aliases at class scope and aliases of other types (with_base_class_t etc.) are kept. No changes to the library or its public API. All changed examples were compiled and run; their output matches the stored .output files (except max_size and meta, which depend on the platform and compiler). Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Format doc examples with the pinned astyle Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-25 12:07:51 +01:00
Niels Lohmann	cc917d7123	docs: cross-reference json_view and json_document for 3.13.0 (#5892 ) * docs: cross-reference json_view and json_document for 3.13.0 Document the new zero-copy document/view API across the docs: add a "Documents and views" section to the basic_json API hub linking to all specializations, point parsing/conversion/modifying pages to the view-based alternatives, add document/view sections to feature pages, update the landing page to mention json_view.hpp/json_literals.hpp, and cross-link debugging/exceptions. Also document wide-string inputs (and ill-formed UTF-16/32 rejection), add parse/accept examples for wide strings, fix related doc gaps, and align features/parsing and FAQ with the added support. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * docs: fix article before std::istream in FAQ Signed-off-by: Niels Lohmann <mail@nlohmann.me> * docs: clarify document inputs, decoding, get<T>() and editing Address review comments: say which inputs are borrowed and that a wide string pointer is an extra input, which values are decoded during parsing, that get<T>() reads only built-in types directly, all forms of set() and that the document's insert() is array-only, and how to store wide strings. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * docs: integers are converted while parsing a document Also say "They accept every input" in basic_json_document::parse. Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-25 06:18:07 +01:00
Niels Lohmann	52b72b5684	Improve documentation: byte layouts, release pages, See also, dark-mode images (#5906 ) - Make the iterator range illustrations legible in dark mode (prefers-color-scheme rules inside the SVGs). - Add a "Byte layout" section with a color-coded byte table to each binary format page (BJData, BON8, BSON, CBOR, MessagePack, UBJSON), and highlight the smallest size per file in the comparison table. - Add "See also" sections to the overview pages that lacked one. - Split the release notes into one page per release, grouped by minor version on the overview page, with an "API changes" section per release generated from the API pages' version histories (hooks/api_changes.py). - Fact-check the release notes and version histories against the release tags and correct wrong or misleading entries (e.g., json_serializer 2.1.0, merge_patch 3.1.0, items, count, operator[], to_bjdata, std::string_view key support). Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-24 17:57:44 +02:00
Niels Lohmann	bd5227c2ec	Fix silent wrong results for custom number types (#5805 ) * Fix silent wrong results for custom number types Squashed onto develop `cd6b428ef` (CI fixes from #5860). Original commits: - Fix silent wrong results for custom number types - Fix CI: build the out_of_range.407 message from string_t and fix a link - Fix CI: diagnostics message, clang-tidy, and MinGW section limit - Format the out_of_range.407 number without dump() - Move the std::deque array test out of unit-regression3.cpp - Fix clang-tidy and clang 3.4/3.5 failures in the custom number type changes - Fix CI: cast the 128-bit unsigned value explicitly in the integer fast path Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Name the range checks of integer_fits_max/min Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-21 08:36:31 +00:00
Niels Lohmann	4c3a3eb5b5	Add dump() and comparisons to json_view (#5624 ) * Add dump() and comparisons to json_view Add basic_json_view::dump() and the comparison operators, and read floats from the parser's digit layout instead of rescanning the token. dump(indent, indent_char, ensure_ascii, number_format) writes a value the way ordered_json::parse(text).dump() writes it for the same arguments: members in document order, all of them should a key occur more than once; strings escaped by the same rules, using the library's scanning kernels; floats written with the library's to_chars conversion, so the output equals basic_json's byte for byte; integers copied from the source, where they are already canonical, except -0, which parse() reads as 0. There is no error_handler argument, because the view only holds valid UTF-8. number_format::source copies numbers exactly as they appear in the source (e.g. "1.50", "1E2", "-0"), which basic_json cannot provide. operator<< takes the indentation from the stream width, as for basic_json. The writer walks iteratively, so nesting depth is limited by memory only. operator== and operator!= compare two views, or a view and a basic_json value in either order, by the rules basic_json's operator== uses: numbers compare by value across their types, objects compare by their members with duplicate keys resolved as parse() resolves them, member order matters only where the object type keeps one, and discarded views compare as discarded basic_json values do, including under JSON_USE_LEGACY_DISCARDED_VALUE_COMPARISON. Nothing is materialized except single scalars. While parsing, the view now records where the integer digits, the fraction digits, and the exponent of a float token are, so floats and doubles with at most 19 digits are read from that layout with the library's decimal_to_float() instead of rescanning the token. Both round correctly, so the values are those of parse(). get<double>(), materialize(), dump(), and the comparisons all use it. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Avoid raw string with escapes inside CHECK macro (MSVC C2017) Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Size the dump buffer of a small value by its own extent The source extent of a value was read from the next node, falling back to the rest of the document when that node held a decoded string. dump() of a small value could thus allocate a buffer as large as the document. Skip a few such nodes, cap the fallback estimate, and shrink a buffer that is much larger than its output. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Hold the documents of the dump and comparison tests in names root() of a temporary document is deleted: its views would dangle. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Do not shrink the output of dump() finish() copied the whole output when the buffer was more than twice as large as the result (citm dump +11%). The tighter source_extent() estimate already keeps the buffer of a small value small. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Document and test first-wins lookups next to dump() and == dump() writes every member and == resolves duplicate keys as parse() does, whereas lookups find the first member of a duplicate key. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Fix the clang-tidy 22 findings in json_view and its tests Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Split the dump and comparison tests off unit-json_view.cpp The MinGW linker of the Windows clang jobs cannot link object files with more than 32767 sections ("relocation truncated to fit: IMAGE_REL_AMD64_REL32 against `.rdata'"). unit-json_view.cpp reaches that limit as the stack grows, so its "json_view dump" and "json_view comparison" test cases move into unit-json_view_dump.cpp. The test generator and has_duplicate_keys() that both files use move into json_view_test_helpers.hpp. The new file mentions JSON_HAS_CPP_17, so it is built for C++17 like the file it was split from. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Make json_view.hpp pass include-what-you-use ci_single_binaries runs IWYU with --error on every header. For json_view.hpp it suggested adding <array> (std::array is used), the headers that json.hpp already provides (abi_config, abi_macros, input_adapters, json_pointer, cpp_future, string_concat, value_t, json_fwd), and <version> for std::nullptr_t, and removing <cstddef>. - include <array> - keep <cstddef> (nullptr_t, size_t; IWYU attributes them to <version> and <cstring>) - tell IWYU not to suggest the headers that json.hpp provides: the amalgamated json_view.hpp only includes json.hpp, so including them here would duplicate their definitions Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Regenerate the amalgamated headers Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Follow the renames from the review of the view builder The review of #5620 renamed document_data's tape/tape_size/tape_cap to nodes/node_count/node_capacity and made the decode arena a std::vector<char>; adapt the code of this change to it. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Keep the stream includes of json_view.hpp for IWYU json_view.hpp uses std::istream and std::ostream itself, but IWYU sees them through the exported json.hpp and asked to remove both includes, which fails ci_single_binaries (single_json_view). Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Address the review of json_view dump() and comparisons From gregmarr's review of #5624: - The output buffer takes string literals without a length. - write_float() names the IEEE single/double condition once, as the library's serializer does. - equal() checks the types first and compares with !=; the reference to the top frame is noted as dangling after pop_back(). - dump.md: one paragraph per case in the notes. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Regenerate the amalgamated headers Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Exclude all json_view test files from Infer's reports The same std::unique_ptr false positive (USE_AFTER_DELETE) also shows for two json_documents parsed in one lambda in unit-json_view_dump.cpp (ci_infer). It affects any test that holds several documents, so the exclusion now covers tests/src/unit-json_view.cpp; ASan and Valgrind cover these tests. Signed-off-by: Niels Lohmann <mail@nlohmann.me> Allow the string literal parameter of the view serializer's put() for clang-tidy The overload takes the literal by array reference so that its length is a template parameter, like scan_literal() and the C array overloads of to_json() and from_json(). Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Bind the serializer's frame only after the check for its end Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Regenerate the amalgamated headers Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-21 10:21:28 +02:00
Niels Lohmann	43e97b629b	Add element access, iteration, values, and JSON pointers to json_view (#5622 ) * Add element access, iteration, values, and JSON pointers to json_view Give basic_json_view the read-only access functions of basic_json: operator[] and at() with keys and indices, front()/back(), find(), contains(), count(), begin()/end() and cbegin()/cend(), items() with structured bindings from C++17 on, and type_name(). Exceptions have the ids and messages of the const functions of basic_json. Where basic_json has undefined behavior the view answers safely: operator[] with a missing key or an out-of-range index returns a discarded view, and front()/back() of an empty container throw invalid_iterator.214. Objects are iterated in document order, and all members are visited; duplicate-key lookups find the first member (as yyjson and simdjson do), while parse(), materialize(), and the map conversions keep the last value, as parse() does. Keys of up to 16 bytes are compared with two overlapping loads. Add value conversions: get<T>()/get_to() for arithmetic types, bool, nullptr_t, strings (std::basic_string copied, string_view_t without a copy), BasicJsonType, views, std::vector, and maps with string keys; get_string() for the string without a copy; number_token() for the number exactly as written in the source; value() with keys and JSON pointers; and operator[]/at()/ contains() with JSON pointers. Everything else, including types with from_json(), goes through materialize() of that subtree. get<T>() of arithmetic types is inlined down to the conversion, so reading an integer needs no call. detail::json_pointer_access exposes a pointer's reference tokens to code outside basic_json. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Make view lookups last-wins and chained access safe * Lookups (operator[], at, find, contains, count, value, JSON pointers) return the last member of a duplicate key, as materialize() and parse() keep it. * operator[] on a discarded view returns a discarded view instead of throwing, so v["a"]["b"] is safe for a missing "a". * operator[] and at() take any integer type (not only int and size_t), fixing ambiguous calls with unsigned, long, std::int64_t, ... * Fix the operator[] documentation, which claimed a discarded view for a type mismatch where type_error.305 is thrown. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Replace the removed operator bool of basic_json_view in the header and its tests A view is tested with is_discarded(); the lookups in at(), value() and contains(json_pointer) and the unit tests no longer rely on the explicit conversion to bool. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Use named documents in the json_view tests that called root() on a temporary root() of an rvalue document is deleted, because the views would dangle. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Test discarded views with is_discarded() in the operator[] docs and examples The explicit conversion to bool of basic_json_view is gone. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Return the first member of duplicate keys from lookups again Looking up the last member of a duplicate key cannot stop at a match, so every lookup scanned the whole object (1.6 to 3.4 times slower for small objects). operator[](key), at, find, value, contains, count, and JSON pointer resolution return the first member again, as yyjson and simdjson do; materialize() and get<map>() keep the last value, as parse(). The documentation says so in the feature page and on each lookup page, and explains how to get the value parse() would give. The integer index templates and the discarded chaining of operator[] stay. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Do not force-inline the view's functions on MSVC __forceinline makes MSVC report C4714 for function templates it cannot inline (get<std::string>), an error under /WX. The forced inlining is only a performance hint, so use plain inline there. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Make json_view.hpp pass include-what-you-use Mark the includes that are needed by design (json.hpp, the macro unscope, <tuple> for the tuple_size specialization), take size_t from <cstring>, and drop the forward declaration of basic_json_document that the friend declaration makes redundant. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Avoid GCC useless-cast warnings in the integer index tests Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Make json_view.hpp pass include-what-you-use ci_single_binaries runs IWYU with --error on every header. For json_view.hpp it suggested adding <array> (std::array is used), the headers that json.hpp already provides (abi_config, abi_macros, input_adapters, json_pointer, cpp_future, string_concat, value_t, json_fwd), and <version> for std::nullptr_t, and removing <cstddef>. - include <array> - keep <cstddef> (nullptr_t, size_t; IWYU attributes them to <version> and <cstring>) - tell IWYU not to suggest the headers that json.hpp provides: the amalgamated json_view.hpp only includes json.hpp, so including them here would duplicate their definitions Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Fix the clang-tidy 22 findings in json_view and its tests The same changes as on the dump branch, where they were first made, so that this branch passes clang-tidy on its own. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Regenerate the amalgamated headers Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Report one-character non-numeric array indices like basic_json in the view Develop's #5800 made basic_json report a JSON pointer array index such as "/a" as parse_error.109 instead of out_of_range.404, as longer ones were; the view's array_index() follows, with "-" and the empty token still unresolved. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Address the review of json_view element access From gregmarr's review of #5622: - count() counts every member with the key, so count(key) > 1 detects duplicate keys; it was contains() as 0/1 before. - get_to() passes types that get<T>() does not convert directly to from_json with the existing value, as basic_json::get_to() does, so that a from_json which sets only the fields present keeps the others. - array_index() checks the empty token and "-" first; the results are unchanged. - Docs: no "if an exception is thrown" where a view never changes anything; the borrowed source must also stay unmodified; items() on a temporary view is safe; back()/front() notes shortened; the basic_json see-also entries say how the view's results can differ. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Regenerate the amalgamated headers Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Count matching keys as unsigned in the json_view access test The conditional added 1 or 0 as int to a std::size_t, which GCC rejects with -Werror=sign-conversion (ci_test_standards_gcc). Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Address the second review round of json_view element access From gregmarr's review of #5622: - begin()/end(): "a null value or a discarded view iterates as an empty range", singular like the primitive case before it. - The class page's list of function groups has no trailing commas. - document_data::key_equals() compares a key node with a string, for the key comparisons that were spelled out in each lookup. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Regenerate the amalgamated headers Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Write the negated enable_if conditions of json_view with negation<> With a ! or && in the condition, astyle spaces the whole template header (template < ... >); detail::negation and a named trait keep it compact, as the library writes such conditions elsewhere. From gregmarr's review of #5630. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Regenerate the amalgamated headers Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Keep detail::negation out of json_view.hpp's enable_ifs include-what-you-use asks json_view.hpp to include detail/meta/type_traits.hpp for it, which the single header must not do (the amalgamation would duplicate json's internals). The two conditions of value() go through a trait in value.hpp, like the others. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Regenerate the amalgamated headers Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-21 10:21:27 +02:00
Niels Lohmann	122d718330	Add json_document and json_view: node index, parser, and document (#5620 ) * Add json_document and json_view: node index, parser, and document Add json_document and json_view, a read-only, zero-copy index of a JSON text, as the first public slice of the zero-copy view (#5295). A parse produces a flat array of 16-byte nodes in document order, one per value and one per object key. Strings stay in the source text; escaped strings are decoded into an arena. Integers are converted while their digits are in the cache; floats keep only their digit layout and are converted on read. Containers store the size of their subtree, so a reader can step over one in constant time. A document makes a handful of allocations, however many values it has. The parser accepts exactly what json::parse accepts, with every combination of ignore_comments and ignore_trailing_commas, with and without a trailing NUL, and under JSON_STRICT_NUL_HANDLING. It is portable C++11 and does not depend on byte order. basic_json_document adds parse, parse_copy, accept, read (reuses a document's memory), root, is_discarded, source, owns_source, node_count, memory_usage, and shrink_to_fit. basic_json_view adds type, the is_* queries, operator bool, size, empty, materialize, and source_offset. A parse error throws the same exception basic_json::parse would throw for the same input, message and position included. detail::abi_config keeps JSON_STRICT_NUL_HANDLING and JSON_USE_LEGACY_DISCARDED_VALUE_COMPARISON readable after json.hpp undefines them, in the ABI namespace so they always match the basic_json in use. A NUL byte that ends a // comment is the end of the input, as in parse() since #5696. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Fix document_data for old Clang (3.4-3.6) Drop the empty braced NSDMIs of the std::string members: old Clang rejects the defaulted constructor when it is used by a member initializer before the end of the class definition. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Exclude libstdc++'s string_view comparison from the sign-change check basic_string_view::_S_compare stores the difference of two lengths in a signed difference_type on purpose, which -fsanitize=integer reports for every comparison with a shorter view (test-json_view_cpp17). Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Reject integer lengths in json_document::parse parse(ptr, len) compiled: len converted to allow_exceptions, and ptr was read as a C string, past the end of a buffer without a terminating NUL. Delete the overloads of parse, parse_copy, accept, and read that take an integer other than bool where the flags are expected. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Copy const rvalue strings and document the accepted inputs json_document::parse(std::move(const_string)) failed to compile with "no matching read_kind": only a non-const rvalue std::string can be moved from. Treat a const rvalue as a copied byte container. parse() does not accept everything BasicJsonType::parse() does: a FILE* and pointers to or arrays of wide characters are rejected at compile time. List the supported inputs instead. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Remove the conversion to bool from json_view explicit operator bool meant "refers to a value", which silently differs from what a basic_json converts to. Use !v.is_discarded() instead. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Delete json_document::root() on temporary documents auto v = json_document::parse(text).root() compiled and left the view dangling. Delete the overload for rvalue documents, take a named document in the tests, and document the lifetime rule. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Store node integers by halves on big-endian targets The non-little-endian path of the node writer wrote the integer's native word over len and next, so len got the high half there. Compose and split the value explicitly (len is the low half, next the high half); the little-endian path stays a plain memcpy. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Check the node array size for overflow reserve(n) and the growth of the index computed n * sizeof(node) without a check, which wraps around on 32-bit targets for inputs of about 1 GiB and allocates a too small array. Throw std::bad_alloc for a count beyond the address space and clamp the growth step to it. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * State the exact input size limit of json_document The check rejects inputs of 0xFFFFFFF0 bytes or more, but the exception message and the documentation said 4 GiB. Name the limit once (max_input_size), and state 4 GiB minus 16 bytes in the message and the documentation. Test the limit with a container that only claims the size. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Remove the unused legacy_discarded_value_comparison from abi_config Nothing reads it: the view does not compare values. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Align the banner comment of json_view.hpp Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Fuzz json_document with exact-size buffers and parse options The fuzzer only parsed a std::string with default options. Also parse an exact-size byte vector, which has no NUL after its last byte and takes the bounds-checked path, and derive ignore_comments and ignore_trailing_commas from the first input byte, comparing against json::parse and json::accept with the same options. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Give document_data a user-provided constructor Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Fix clang-tidy findings in unit-json_view_builder.cpp Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Annotate intentional patterns in unit-json_view.cpp for clang-tidy Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Suppress Flawfinder's read() finding on the deleted overload Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Check the steps of the deep-nesting test separately Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Make max_input_size a function (GCC -Wunused-const-variable) Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Make json_view.hpp pass include-what-you-use ci_single_binaries runs IWYU with --error on every header. For json_view.hpp it suggested adding <array> (std::array is used), the headers that json.hpp already provides (abi_config, abi_macros, input_adapters, json_pointer, cpp_future, string_concat, value_t, json_fwd), and <version> for std::nullptr_t, and removing <cstddef>. - include <array> - keep <cstddef> (nullptr_t, size_t; IWYU attributes them to <version> and <cstring>) - tell IWYU not to suggest the headers that json.hpp provides: the amalgamated json_view.hpp only includes json.hpp, so including them here would duplicate their definitions - export json.hpp, keep macro_unscope.hpp, and drop the unused forward declaration of the document class Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Read the node array base after emit() in the view builder's open() emit() moves the node array when it grows, and the subtraction read base in the same expression, so the order was unspecified. MSVC Release builds without forced inlining read the old base; the container index then pointed outside the array and close() wrote out of bounds. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Silence a clang-tidy use-after-move finding in the json_view test const_text is const, so std::move does not move from it; the second call is part of the const rvalue test. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Regenerate the amalgamated headers Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Address the review of the view builder and document Changes promised in the replies to the review of #5620: - read() reuses the owned copy: a copied input (an rvalue byte container, a stream, FILE, wide characters, an iterator range) is appended to the cleared owned buffer instead of a fresh std::string being move-assigned over it. A moved-in std::string still replaces it. - The error replay runs the library parser with a SAX handler that stores nothing and throws the reported exception, instead of BasicJsonType::parse(), which built a DOM up to the error. - Pointers to and arrays of wide characters, and FILE, take the input adapter path (converted to UTF-8 into an owned buffer) instead of failing a static_assert. Wide pointers are NUL-terminated. - Streams are read in blocks through rdbuf() into the buffer, instead of character by character through the input adapter; eofbit is set at the end, as by the library's stream adapter. - tape/tape_size/tape_cap are now nodes/node_count/node_capacity. - The builder's members get descriptive, m_-prefixed names. - The shallow frame stack is a std::array (in a wrapper with a user-provided constructor: -Weffc++ wants the member initialized, and value-initializing the 64 frames costs up to 30 % on small documents). - The value dispatch macro has no NEXT parameter; the switch is left with break, and the macro is undefined after its last use. - literal() and digits_exceed() deduce the length from the string literal; each literal has one helper; the two `if (!is_float)` blocks are merged. - arena_ensure() sits right before the writes; the decode arena is a std::vector<char>. - The builder records the deepest nesting, and materialize() sizes its stack from it once (growing it only if a subtree is deeper). - Comment fixes (hex4, slow_string, the NUL rule, put_utf8, 0 - m, the arena resize, grow()) and formatting (macro backslashes, digit cases, one power of ten per line, value_t assertion next to is_container()). - build_with's template parameters follow the builder's order. Greg's idea of keeping the source offset in `off` and the arena offset in `next` for escaped strings was measured and not adopted: string access got 7-18 % slower with a select, and 3.5-18 % slower with a branch-free field pick (Apple M-series, clang -O3), parsing was unchanged. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Apply the review's wording fixes to the json_view documentation - Copying is disabled because of its cost, not because of two documents borrowing the same buffer; the unique_ptr follows from move-only. - Inputs: streams, FILE, and wide characters (strings, arrays, pointers) are all supported and owned; point to parse_copy() for owned copies. - The error replay only runs for failing input, builds no values, and is skipped with allow_exceptions = false. - read() writes copied inputs into the previous owned copy. - Views can dangle like std::string_view, and why there is no shared/weak pointer design. - The 4 GiB limit (16-byte nodes, 16-byte scanner steps), streams being read to the end first, which macros apply, why materialize() has no source positions, and wording nits (accept() vs basic_json::accept(), is_binary, is_discarded, see-also lists, size table, "back into"). Signed-off-by: Niels Lohmann <mail@nlohmann.me> Say that json_view converts integers while parsing Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Address the review: null inline nodes, trait spelling, and max() in json_view - inline_nodes is null when the document has no inline nodes, instead of pointing past the end of the allocation; shrink_to_fit() no longer passes it to memcpy() for an empty node array - is_byte_char and is_wide_char use conjunction/disjunction, which astyle leaves unspaced - append_stream() uses (std::max) for the count read Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Include materialize.hpp in the view builder test The test calls detail::view::materialize(), which only the single header pulled in; the multiple-header build (JSON_TEST_USING_MULTIPLE_HEADERS) failed with "'materialize' is not a member of detail::view". Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Rename emit() in the view builder for Qt compatibility Qt defines emit as an empty macro, so a Qt header included before json_view.hpp broke the declaration of the builder's emit(), see issue #5865. It is now called push_node(). Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Do not copy an empty run into an unallocated arena memcpy() must not be passed a null pointer even for zero bytes, which arena_run() did for an empty run while the arena was still empty (ci_test_clang_sanitizer: "null pointer passed as argument 1" in builder.hpp). Only the slow path can see such a run. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Exclude the view builder test from Infer's reports Infer's std::unique_ptr model confuses the values that the test's build() helper returns by value and reports USE_AFTER_DELETE for one of them after the destructor of an unrelated temporary (ci_infer, 12 reports, all in tests/src/unit-json_view_builder.cpp). AddressSanitizer is clean on the same tests. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Skip the deleted-overload checks of json_view on MSVC 2015 MSVC 2015 does not treat selecting a deleted function in decltype as a substitution failure, so is_detected reports the deleted parse/parse_copy/accept/read(ptr, len) overloads as callable and the static_asserts in "integer arguments do not compile" fail (AppVeyor VS2015 jobs). Calling them still fails to compile there. Guard the negative checks as unit-delete_deprecated_functions.cpp does. Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-21 10:21:27 +02:00
Niels Lohmann	4da932f518	Make parsing from std::istream and FILE* fast (#5828 ) * Make parsing from std::istream and FILE* fast Squashed onto develop `cd6b428ef` (CI fixes from #5860). Original commits: - Let the lexer's bulk fast paths run on a window of the input - Scan the get area of an input stream in bulk - Lock a FILE once per parse instead of once per character - Add benchmarks for parsing from a FILE* and for many values from a stream - Avoid implicit unsigned char to char conversion in stream tests - Make file_input_adapter::unlock() safe to call on a moved-from adapter Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Add ABI tags for JSON_DISABLE_STREAM_BULK_SCAN and JSON_DISABLE_UNLOCKED_FILE_IO Both macros select between two definitions of an input adapter, so translation units compiled with different settings violated the ODR when linked together. Like the other ABI-affecting macros, they now append a tag to the inline namespace: _dsbs and _dufio. Their defaults move to abi_macros.hpp so that json_fwd.hpp sees them, and the natvis file is regenerated for the new namespaces. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Skip the exception-only checks of the stream input tests without exceptions Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-19 22:00:58 +02:00
Niels Lohmann	ce28c722bc	Allow the same type for number_integer_t and number_unsigned_t (#5815 ) * Allow the same type for number_integer_t and number_unsigned_t basic_json did not compile with NumberUnsignedType == NumberIntegerType because overloads on both types collided. Such a basic_json now stores every integer as number_integer: the colliding overloads take a placeholder type, unsigned C++ integers are converted to number_integer_t, and value_t::number_unsigned maps to number_integer. Also fixes two problems this configuration would hit: the unsigned integer parser accepted values that wrap around to negative numbers, and dump() overflowed when computing the absolute value of the minimum. A repeated NumberFloatType gets a static_assert. Refs #2573 Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Use json::with_integers_t in the test and the docs Signed-off-by: Niels Lohmann <mail@nlohmann.me> * ✅ skip patch test on GCC 5 to avoid internal compiler error Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Fix CI: name the unsigned overload type through template parameters basic_json used number_unsigned_overload_t<basic_json> while the class was still incomplete. MSVC rejected it as a recursive alias declaration and GCC 4.9, 5 and 7 crashed with an internal compiler error. basic_json now uses number_unsigned_overload_type<NumberIntegerType, NumberUnsignedType>, which also makes the GCC 5 workaround in the patch test unnecessary. Infer reported a null dereference for the number_unsigned case in from_json, which cannot happen for a basic_json whose number_unsigned_t is number_integer_t; assert it. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Address review: conjunction/negation trait, astyle-friendly alias, docs table order Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-15 20:04:42 +02:00
Niels Lohmann	ca7740fef2	Move elements when converting rvalue containers to JSON (#5837 ) * Move elements when converting rvalue containers to JSON Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Simplify the rvalue to_json traits Use negation<disjunction<...>> instead of a conjunction of negations and keep the template argument lists compact (astyle only keeps the spaced '< ... >' form when it is written that way). Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-15 20:01:20 +02:00
Niels Lohmann	4e294f4b18	Clarify that double is only the default floating-point type in the docs (#5830 ) Follow-up to review comments on #5825: number_float_t uses double precision only by default, and the stated limits apply to double. Also say "default type for X_t" instead of "default value for X_t". Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-14 18:28:49 +02:00
Niels Lohmann	ccc005c012	Fix contradictions between the documentation, the README, and the library (#5825 ) - Discarded values: the legacy macro only changes <= and >=; != is true by default - Out-of-range numbers are rejected while parsing, not stored as NaN - merge_diff round trip: point to the ordered_json caveat - ensure_ascii example shows the escaped output - out_of_range.405 is thrown for "remove"/"move" on the root, not "add" - CBOR stores binary subtypes as tags - Integer/float comparison uses exact values, not conversion - diff, flatten, and the binary writers are depth-bounded - FAQ: max_digits10 for serialization, trailing commas are supported - out_of_range.407 is still thrown by to_bon8 - FetchContent_MakeAvailable needs CMake 3.14 - json_fwd.hpp contents, operator< link, RFC 7396 for merge patch - README: dump() wording, merge_diff, MSYS2/build2, patch comment typos, operator[] link, embedded CMake example aligned with the docs Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-14 17:40:55 +02:00
Niels Lohmann	91a7a94cc6	Write doubles with the shortest digits (Żmij), digits in registers (#5634 ) * Write doubles with the shortest digits (Żmij), digits in registers Write doubles with the conversion of Zmij by Victor Zverovich (MIT), ported to C++11 (detail/conversions/zmij.hpp). It finds the shortest decimal that reads back as the same double, and the closest one if there are several. Grisu2, used until now, is fast but not always shortest: it sometimes writes a 17th digit where 16 suffice, or a last digit that is not the closest. The layout is unchanged (1.5, 100.0, 1e+100, -0.0); float keeps Grisu2. Digits are converted eight at a time with the BCD conversion of Xiang JunBo, as in Zmij, and written with one byte swap per eight digits and fixed-size moves instead of per-digit loops. Leading and trailing zeros are counted from those bytes. to_chars() uses a local buffer when the caller's is shorter than the 41 bytes this may write. The powers of ten come from the number-parsing table, adjusted where it holds values rounded up, and extended with Zmij's compressed tables beyond 10^308. write_shortest() converts its 16 digits in one vector register (SSE2 on x86-64, NEON on 64-bit Arm, both baseline) and inserts the decimal point inside the register, avoiding a store-forwarding stall that cost about 25% of the time to write a double. dump() writes floats and integers straight into the serializer's write buffer instead of copying them from a member buffer, and small integers eight digits at a time. read_eight_bytes() and parse_eight_digits() are marked always-inline, which GCC had been calling out of line in the number-parsing loops. Of one million random doubles, about 0.14% are now written with different digits, always to a value that still reads back as the same double. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Fix CI findings in the Zmij writer and its tests - bit_ops.hpp: include macro_scope.hpp (JSON_HEDLEY_ALWAYS_INLINE); fixes IWYU - to_chars.hpp: C4100 for the unused parameter in release builds, clang-tidy sign comparison, cpplint runtime/int, GCC -Wstrict-overflow (unsigned abs) - unit-to_chars.cpp: parse with the library instead of strtod (MinGW's strtod rounds some 16/17 digit inputs wrongly); no floating-point std::to_chars with icpc Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Select the Zmij conversion by a trait, not by the double overload The non-template overloads for double asserted binary64 doubles wherever json.hpp was included, so the library no longer compiled where double is not IEEE 754 binary64 (AVR, -fshort-double). A trait now picks Zmij for any binary64 type, including a long double of that format (MSVC, Apple Arm), and Grisu2 for the others. Remove the unused write_short_decimal, powers_of_ten_16, zmij::decimal, zmij::to_decimal, and shortest_digits(double). Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Credit Zmij's authors in to_chars.hpp, the README, and the license page Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Silence MSVC C4127 for a platform-constant check in the to_chars test Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Regenerate the amalgamated headers Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-14 17:38:37 +02:00
Niels Lohmann	5b4c8f9b00	Speed up the lexer: own float parser, string scan, and \u table (#5738 ) * Speed up the lexer: own float parser, string scan, and \u table Give the library its own correctly rounded float converter for binary32 and binary64 (IEEE 754), and speed up the lexer's string and escape scanning. The converter splits a number token into sign, significand, and decimal exponent, then tries Clinger's fast path, then a templated Eisel-Lemire step, and falls back to an exact big-integer digit comparison for tokens with more than 19 significant digits whose two candidate values round differently. This replaces std::from_chars and strtod/strtof for both formats, so parsed values no longer depend on the C/C++ library or the current locale. The strtold fallback kept for other long double formats (x87, binary128) now also copies a multi-byte decimal point correctly, fixing #5660. eisel_lemire() and decimal_to_float() are always inlined so callers keep the whole conversion in their hot loop. The string-scanning kernels in string_scan.hpp find a stop byte with the trailing-zero count of the SWAR mask instead of a byte loop, and scalar_string_bulk_run() validates a run of multi-byte UTF-8 sequences one after another instead of re-searching after each one. get_codepoint() decodes a contiguous \uXXXX escape with one table lookup per byte instead of four range-checked get() calls; the streaming path and all error positions are unchanged. Adds 508 generated hard float-parsing cases with expected binary32 and binary64 bits, and kernel-comparison tests for the string scans and the escape table against byte-by-byte references. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Fix CI warnings in own float parser - pow5_table.hpp: pow5_128_largest_power was unused in this branch's own code (GCC -Werror=unused-const-variable); tie it to the table size with a static_assert instead of removing it, since a later branch in the stack (json-view/23-zmij) uses it. - number_parse.hpp: rename the local variable `copy` to `buffer` to satisfy cpplint's build/include_what_you_use check. - unit-class_lexer.cpp: extend the NOLINT list on the seeded mt19937 with bugprone-random-generator-seed, and parenthesize `8 * sizeof(Bits) - 1` for clang-tidy. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Load string scan words with memcpy and use MSVC bit-scan intrinsics Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Reword float conversion notes for the string type and number_float_t docs Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Fix clang-tidy 22 findings in unit-class_lexer.cpp Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Mark the unsigned long of the MSVC bit scans for cpplint Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Regenerate the amalgamated headers Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Drop the position updates in the bulk \u path, which #5809 made unused Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Address review: std::any_of in has_nonzero_digit, comment punctuation Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Use data() instead of c_str() in the multi-byte decimal point path Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-14 17:38:36 +02:00
Niels Lohmann	7461a199b5	Drop the class wrapper from the C++20 comparison operator signatures in the docs (#5814 ) * Drop the class wrapper from the C++20 comparison operator signatures in the docs The signature boxes of operator<=> and the C++20 half of operator== wrapped the member declarations in an incomplete "class basic_json { ... };". The trailing const already marks them as members, and no other page uses such a wrapper. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Drop the class wrapper from the json_pointer comparison signatures too Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-13 20:06:14 +02:00
satelliteprogrammer	40a62947d3	support JSON Merge Patch (RFC 7396) diff creation (#4965 ) * support JSON Merge Patch (RFC 7396) diff creation The JSON merge patch document format describes the set of modifications to a resource's content, that more closely mimics the syntax of the resource being modified. However, and in contrast to JSON Patch (RFC 6902), a JSON Merge Patch cannot express certain modifications, e.g., changing an array element at a specific index, or setting a specific object value to null. The null value in a JSON Merge Patch is used to remove the key from the object. The diff algorithm is not part of the RFC 7396, but it was tested against all examples provided, plus additional cases on how null values are handled. Signed-off-by: Luís Murta <luis@murta.dev> * improve algorithm efficiency Signed-off-by: Luís Murta <luis@murta.dev> * fix inconsistent nulls and empty arrays Also add CHECKs for the patch, documentation and run `make amalgamate`. Signed-off-by: Luís Murta <luis@murta.dev> * documentation cleanups Signed-off-by: Luís Murta <luis@murta.dev> * add an iterative fallback to merge_diff Bound the recursion depth like diff() and merge_patch(), and test values nested past the bound. Signed-off-by: Luís Murta <luis@murta.dev> * address the remaining review comments Signed-off-by: Luís Murta <luis@murta.dev> * move multi-line raw strings out of CHECK macros GCC 4.8/5, ICPC and NVHPC mis-tokenize multi-line raw string literals inside macro arguments, breaking the build or the parsed JSON. Signed-off-by: Luís Murta <luis@murta.dev> --------- Signed-off-by: Luís Murta <luis@murta.dev>	2026-10-12 09:33:43 +02:00
Niels Lohmann	eb8899a29c	Restore v3.12.0 support for custom object key types (#5795 ) * Restore v3.12.0 support for custom object key types Custom object_t types whose key_type is not string_t compiled with v3.12.0 for several APIs that unreleased changes broke: - to_bson failed for every custom key type (#5553 kept a const string_t* to the key); the nested entry's header is now written where the entry is found. - Copying deep values (and parse, merge_patch, update, insert) required operator== on keys (#5389); keys without one are now paired via find(). - to_cbor/to_msgpack required an implicit conversion to string_t (#5746, #5328); keys without one go through a temporary basic_json again. - at() required a conversion to string_t for its error message (#5727); other keys are passed to concat() unchanged again. The new unit-custom-object-key-type.cpp covers five key types with different capabilities. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Use the with_object_t alias for the custom object key test types Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Avoid floating-point equality in custom key type test GCC with -Werror=float-equal rejects comparing the double value with ==. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Write the head of nested BSON elements in one helper Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Suppress bugprone-return-const-ref-from-parameter in key_for_message The reference is only passed to concat() within the full-expression that holds the key, like the similar helpers in binary_writer.hpp. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Make the value of the custom test key types private clang-tidy (cppcoreguidelines-non-private-member-variables-in-classes) rejects the protected member; the derived key types use a protected accessor instead. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Pass keys with data() and size() unchanged into the at() miss message key_for_message() converted every key that string_t can be constructed from, so a miss on a string_t or string_view key copied it before concat() copied it again. Keys that concat() can append through data() and size() are now passed through; only other keys (string literals, key types that just convert to string_t) are converted. Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-11 08:24:31 +02:00
Niels Lohmann	11ef352511	Point users to update(…, true), JSON Pointer defaults, and built-in std::optional (#5804 ) A code search of client code found many hand-written versions of functionality the library already has: recursive object merges (update(j, true) since 3.10.5), dotted-path getters (value() and contains() with a JSON Pointer), get_or helpers (value() throws for a member that is present but null), and adl_serializer specializations for std::optional (supported since 3.12.0). - modifying_values.md: describe both modes of update(), add a defaults + user settings recipe, and stop recommending Merge Patch for recursive merges. - merge_patch.md: note that null deletes keys, so a merge patch is not a general deep merge; link update(). - default_value.md: add "Nested values" (value/contains with a JSON Pointer, building a pointer from a dotted path with operator/=) and a warning that null and mistyped members are not missing. - value.md: note that a null member is converted, not replaced by the default. - json_pointer.md: link value/contains/at with JSON Pointers. - arbitrary_types.md: note that std::optional needs no serializer. Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-11 08:22:10 +02:00
Niels Lohmann	74a03dec84	Throw type_error.321 for discarded values in to_bon8 (#5802 ) write_bon8_value silently skipped discarded values, but the array/object count marker still counted them, so [1, discarded] produced 82 91: a marker announcing two elements followed by one. Throw type_error.321 like the other binary writers do, at any nesting level. Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-11 08:22:00 +02:00
Niels Lohmann	6197341a21	Clean up non-code files (#5801 ) * Clean up README, contribution guide, and repository metadata - REUSE.toml: fix the Hedley path and SPDX id (CC0-1.0), mark the docset icons as the public-domain JSON logo - CITATION.cff: v3.12.0 was released on 2025-04-11 - FILES.md: list all workflows, describe the Meson option defaults - README: ctest -LE, table of contents, typos, stale Android/MinGW advice, moved links, merge duplicate Thanks entries, list the analysis tools used in CI - CONTRIBUTING: iterative parser, json_literals.hpp is generated, links - .gitignore: backups and release outputs; .gitattributes: mark generated files - labeler: label other build systems and .github documentation - MODULE.bazel: add the module version Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Clean up CI, CMake, Makefile, and Bazel files - CMakeLists.txt: avoid VERSION_GREATER_EQUAL, which CMake < 3.7 lacks - ci.cmake: test JSON_DisableTupleReferenceConversion in ci_cmake_flags, remove unused variables and unreachable per-compiler targets, look up Clang tools consistently, forward CMAKE_CXX_FLAGS to ci_module_cpp20, format json_literals.hpp and remove backups in ci_test_amalgamation - BUILD.bazel: add json_literals.hpp to the single-header target - workflows: format json_literals.hpp before copying it, drop the obsolete natvis --version plumbing, name natvis and macro_builder in failure messages, drop the duplicate amalgamation job, install Valgrind only where needed, republish docs on version bumps, fix stale names - Makefile: complete .PHONY and help, check-amalgamation always restores the checked-in files, natvis uses its own venv, macro_builder_check installs astyle, clean removes the fuzzer binaries - remove tools/amalgamate/config_json_view.json (json_view.hpp is not on develop yet) Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Fix inaccuracies in the documentation - version history: json_base_class_t (3.11.3), JSON_HAS_CPP_11 (3.10.0), JSON_HAS_RANGES exclusions, define-type macros, ABI tags - releases: 3.12.0 raised the minimum CMake version - from_: the (ptr, len) overloads are deleted, not removed, in 4.0.0 - contains/count/find: document the deleted integral overloads - add JSON_HAS_RANGE_VIEW_CONVERSION and list the JSON_HAS_ macros in the macro overview - mention BON8 and error_handler where binary formats are listed - broken links, outdated URLs, warning count, Hunter v0.26.12 - copy_markdown_source hook: expand snippets in the Markdown copies Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Pass /EHsc to the Windows C++20 module build ci_module_cpp20 now forwards CMAKE_CXX_FLAGS to the module build. The Windows workflow sets CMAKE_CXX_FLAGS, which replaces CMake's MSVC defaults including /EHsc, so <chrono> failed with C4530 under /WX. Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-11 08:21:51 +02:00
Niels Lohmann	2cca04ae6f	Report one-character non-numeric array indices like longer ones (#5800 ) * Report one-character non-numeric array indices like longer ones A JSON pointer reference token that is not a number but has only one character (e.g. "/a/x") was reported as out_of_range.404 ("unresolved reference token"), because the "is not a number" check only ran for tokens longer than one character; "/a/xy" got parse_error.109. Both now throw parse_error.109. "-" and the empty token are still reported as out_of_range.404. As a consequence, value(json_pointer, default) on an array now throws for "/x" as it already did for "/xy". Also document why ordered_map::erase's destroy/placement-new loop on pair<const Key, T> is kept despite [basic.life]/8 before C++20. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Document the one-character array index change Add 3.13.0 version-history entries to at, operator[], value, patch, patch_inplace, and unflatten, and describe in exceptions.md which array indices throw parse_error.109 and which out_of_range.404. Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-11 08:21:41 +02:00
Niels Lohmann	d540750f21	Use the with_*_t aliases in the remaining tests and docs (#5790 ) #5787 missed the instantiations spelled as `basic_json <` (astyle's formatting) or ending in the CustomBaseClass argument. Convert them, including the binary_t.md example pointed out in review. Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-09 16:56:14 +02:00
Alex Prabhat Bara	69a0c1b82c	Avoid allocating temporary basic_json for cbor and msgpack object keys (#5328 ) * avoid allocating temporary basic_json for CBOR and MessagePack object keys Signed-off-by: alexprabhat99 <alexpbara@gmail.com> * add size() to the custom object key test type UBJSON and BJData access object keys through size() and c_str() directly, so the key type now provides both and the comment says why. Signed-off-by: alexprabhat99 <alexpbara@gmail.com> * address review: drop key size()/c_str(), test keys below the depth limit Nothing in the library calls size() or c_str() on an object key, so the test key type only keeps data(), which JSON_DIAGNOSTICS needs. The CBOR and MessagePack custom key tests now also nest objects deeper than detail::recursion_depth_limit(), so keys written by write_cbor_iterative and write_msgpack_iterative are covered as well. Signed-off-by: alexprabhat99 <alexpbara@gmail.com> --------- Signed-off-by: alexprabhat99 <alexpbara@gmail.com>	2026-10-09 13:22:07 +02:00
Niels LohmannandAfonso Januário	a5f5d3059b	Make std::hash<basic_json> consistent with operator== for numbers (#5772 ) * Make std::hash<basic_json> consistent with operator== for numbers operator== converts between number_integer, number_unsigned, and number_float before comparing, so json(0), json(0U), and json(0.0) all compare equal. hash() folded the specific value_t into the result for each of the three numeric cases, giving each a distinct hash and breaking the standard Hash requirement that a == b implies hash(a) == hash(b). A std::unordered_set could therefore hold all three as separate elements even though they compare equal. hash() now treats all three numeric variants the same way: it converts the value to number_float_t and combines it with a single shared type tag, so any two numbers operator== considers equal hash identically regardless of which internal type actually holds them. Updated the accompanying test to check this consistency directly (including via an actual unordered_set) instead of asserting that 0, 0U, and 0.0 hash differently, since that assumption was the bug. Also corrected the function's own doc comment and the std::hash API docs, which described the old behavior as intended. Fixes #5400 Signed-off-by: Afonso Januário <afonso-januario@hotmail.com> Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Remove now-unused number_integer_t/number_unsigned_t typedefs in hash() Merging the three numeric branches into one that only reads number_float_t left these two aliases unused, which several CI configurations treat as a build error under -Wunused-local-typedefs. Signed-off-by: Afonso Januário <afonso-januario@hotmail.com> Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Mark the unordered_set in the hash regression test const clang-tidy's misc-const-correctness check flagged it: the set is never mutated after construction, only read via size(). Signed-off-by: Afonso Januário <afonso-januario@hotmail.com> Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Normalize -0.0 in number hashes and test range ends operator== compares numbers exactly since #5459, so equal numbers share one value and convert to the same number_float_t. Update the comment accordingly, map -0.0 to 0.0 before hashing (std::hash need not do that), and test -0.0 and the ends of the integer ranges. Show hash(0.0) in the docs example and note the change in the version history. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Clarify hash documentation after review - Say "may hash differently" for null, false, and numbers, since a collision across types is possible. - Name the storage types (signed integer, unsigned integer, floating-point number) instead of example literals. - Explain that the hash survives converting an integer to number_float_t but not the lossy conversion back, and that unequal numbers may share a hash. - State that the example hash values are illustrative only and vary by platform, compiler, compiler version, and library version. Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Afonso Januário <afonso-januario@hotmail.com> Signed-off-by: Niels Lohmann <mail@nlohmann.me> Co-authored-by: Afonso Januário <afonso-januario@hotmail.com>	2026-10-07 19:18:51 +02:00
Mohd Quamar TyagiandNiels Lohmann	675e519966	Allow SAX parsing of tagged CBOR (#5740 ) * Allow SAX parsing of tagged CBOR Signed-off-by: Tyagiquamar <mohdquamartyagi@gmail.com> * Consolidate sax_parse overloads with default tag_handler parameter Signed-off-by: Tyagiquamar <mohdquamartyagi@gmail.com> * Add version history entry for tag_handler in sax_parse documentation --------- Signed-off-by: Tyagiquamar <mohdquamartyagi@gmail.com> Signed-off-by: Niels Lohmann <mail@nlohmann.me> Co-authored-by: Niels Lohmann <mail@nlohmann.me>	2026-10-07 07:38:24 +02:00
Niels Lohmann barcode Raphael Grimm	162e13b86f	Add with__t alias templates to create basic_json types with changed template parameters (#5758 ) Add helper types to make it easier to create a basic_json type with modified template parameters Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Rename with_changed__t aliases to with__t and merge integer/unsigned aliases Per review discussion on #3898 between gregmarr and nlohmann: - rename with_changed_X_t to with_X_t for brevity - replace the separate with_changed_integer_t/with_changed_unsigned_t aliases with a single with_integers_t<NumberIntegerType2, NumberUnsignedType2> - add @sa doc comment links for the upcoming documentation page Co-authored-by: Raphael Grimm <1005058+barcode@users.noreply.github.com> Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Add documentation for the with__t member alias templates Add docs/mkdocs/docs/api/basic_json/with_t.md documenting with_object_t, with_array_t, with_string_t, with_boolean_t, with_integers_t, with_float_t, with_allocator_t, with_json_serializer_t, with_binary_t and with_base_class_t, with an accompanying example, and link the page from the basic_json member types list and the mkdocs navigation. Co-authored-by: Raphael Grimm <1005058+barcode@users.noreply.github.com> Signed-off-by: Niels Lohmann <mail@nlohmann.me> Add tests for the with__t member alias templates Check with std::is_same that each with__t alias produces the expected basic_json type, and that with_string_t keeps nlohmann::ordered_map as the object type when used on ordered_json. Co-authored-by: Raphael Grimm <1005058+barcode@users.noreply.github.com> Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Fix with_t nav entry and document chaining of the with__t aliases Indent the with_t entry in mkdocs.yml so it is listed under basic_json, explain that the aliases can be chained and work on ordered_json, and test both, including json::with_object_t<ordered_map> == ordered_json. Signed-off-by: Niels Lohmann <mail@nlohmann.me> Add docset entry for basic_json::with_t Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me> Co-authored-by: barcode <barcode@example.com> Co-authored-by: Raphael Grimm <1005058+barcode@users.noreply.github.com>	2026-10-06 22:33:29 +02:00
Niels Lohmann ameliabarnabyhub ameliabarnabyhub	5379e04ce4	Throw type_error.321 when serializing discarded values to binary formats (#5761 ) * Throw type_error.321 when serializing discarded values to binary formats The CBOR, MessagePack, UBJSON, BJData, and BSON writers silently skipped the payload of a value_t::discarded value nested in an array or object, while still writing its slot in the element/member count (and, for BSON, its entry header), producing a binary document whose declared size does not match what was actually written. Throw type_error.321 instead, for a discarded value anywhere in the tree, including at the top level. Rewritten from the original PR against the current (non-recursive option aside) binary_writer.hpp, which has changed substantially since this was first proposed; the out_of_range.412 MessagePack size check and unrelated test reformatting from that PR are dropped as out of scope here. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Document and test type_error.321 for discarded binary values Add docs for the new exception (home/exceptions.md and the Exceptions sections of to_cbor/to_msgpack/to_ubjson/to_bjdata/to_bson) and test coverage for a discarded value nested in an array or object, nested deeper, and (for UBJSON/BJData) inside an optimized same-type array, for each of CBOR, MessagePack, UBJSON, BJData, and BSON. Adjust the three pre-existing "discarded" tests that asserted the old silent behavior (empty/short output) to expect type_error.321 instead. Co-authored-by: ameliabarnabyhub <312084480+ameliabarnabyhub@users.noreply.github.com> Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me> Co-authored-by: ameliabarnabyhub <ameliabarnabyhub@users.noreply.github.com> Co-authored-by: ameliabarnabyhub <312084480+ameliabarnabyhub@users.noreply.github.com>	2026-10-06 07:33:34 +02:00
Niels Lohmann	c5a7a4b46d	Add deprecated from_bon8/from_bjdata(ptr, len) overloads (#5688 ) from_bon8(ptr, len) and from_bjdata(ptr, len) had no overload for a pointer and a length, unlike from_cbor/from_msgpack/from_ubjson/ from_bson. The call instead bound to from_*(InputType&&, bool strict), which read ptr as a NUL-terminated C string via strlen and silently converted len to the strict flag. Data containing a 0x00 byte was cut off there; data without one was read past the end of the buffer. Add a deprecated (ptr, len, strict, allow_exceptions) overload for each function that forwards to (ptr, ptr + len, ...), matching the existing deprecated overloads of the other four binary readers. Since neither function ever had this overload, the deprecation is declared as of version 3.13.0, the next unreleased version, rather than the version each function was originally added in. Fixes #5648. Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-04 22:11:34 +02:00
Niels Lohmann	4f69be80d6	Clarify wording in diff documentation (#5759 ) Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-04 18:20:20 +02:00
Niels Lohmann	6b4b825af2	Handle numbers that do not fit narrow number types in the binary readers (#5607 ) * Handle numbers that do not fit narrow number types in the binary readers With custom number types narrower than the values in a binary document, for example basic_json<..., std::int32_t, std::uint32_t, float>, every binary reader (CBOR, MessagePack, UBJSON, BJData, BSON, BON8) passed the decoded number to the SAX interface with an implicit conversion: the integer 5000000000 silently became 705032704, and a finite double such as 1e300 became infinity. The lexer handles the same values in JSON text: an integer that fits neither integer type is stored as number_float_t, and a finite number that overflows number_float_t is rejected with out_of_range.406. Pass every number read from binary input through three helpers that apply the lexer's rules: - emit_signed(): number_integer_t, else number_unsigned_t for a non-negative value, else number_float_t - emit_unsigned(): number_unsigned_t, else number_float_t - emit_float(): out_of_range.406 if a finite value overflows number_float_t; infinity and NaN are passed on For consistency, a CBOR negative integer below the range of number_integer_t is now stored as number_float_t, like a too small integer in JSON text, instead of being rejected with parse_error.112. With the default number types, this is the only change in behavior. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Fix MSVC and clang 3.5 in the narrow number type test MSVC types 3000000000 and 5000000000 as unsigned long, so json(-3000000000) triggered C4146 (unary minus on an unsigned type), which /WX turns into an error. Use LL literals, as elsewhere in the tests. clang 3.5 cannot convert the lambdas in the braced initializer of the format table to function pointers. Use named functions instead. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Check integer-to-float fallbacks for overflow in the binary readers emit_signed, emit_unsigned, and the CBOR negative integer fallback now pass their number_float_t fallback through emit_float, so a value that overflows number_float_t is rejected with out_of_range.406 like a floating-point value, instead of silently becoming infinity. This only matters for a number_float_t that cannot represent 2^64, such as a half-precision type. The CBOR value -1 - n is computed as long double so that emit_float sees a finite value. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Use the input_format member instead of passing the format to binary_reader helpers The helpers (get_number, get_to, get_string, get_binary, get_bytes, emit_signed, emit_unsigned, emit_float, unexpect_eof, exception_message) are members of binary_reader, which already stores the format it was constructed with, so the parameter was redundant. Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>	2026-10-04 17:53:29 +02:00

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