Nlohmann-json

- Release date: 2016-09-11
- SHA-256: 632ceec4c25c4e2153f71470d3a2b992c8355f6d8b4d627d05dd16095cd3aeda

Summary

This release fixes a bug in the stream parser (function `parse()` and the `<<`/`>>` operators). This fix is backwards compatible.

Changes
- **Bug fix**: The end of a file stream was not detected properly which led to parse errors.
- Fixed a compiler warning about an unused variable.

- Release date: 2016-08-31
- SHA-256: 535b73efe5546fde9e763c14aeadfc7b58183c0b3cd43c29741025aba6cf6bd3

Summary

This release combines a lot of small fixes and improvements. The release is backwards compatible.

Changes
- The **parser/deserialization functions have been generalized** to process any contiguous sequence of 1-byte elements (e.g., `char`, `unsigned char`, `uint8_t`). This includes all kind of string representations (string literals, char arrays, `std::string`, `const char*`), contiguous containers (C-style arrays, `std::vector`, `std::array`, `std::valarray`, `std::initializer_list`). User-defined containers providing random-access iterator access via `std::begin` and `std::end` can be used as well. See the documentation ([1](https://nlohmann.github.io/json/classnlohmann_1_1basic__json_ace63ac4eb1dd7251a259d32e397461a3.html#ace63ac4eb1dd7251a259d32e397461a3), [2](https://nlohmann.github.io/json/classnlohmann_1_1basic__json_a90f05d55d9d0702c075cd281fd0d85ae.html#a90f05d55d9d0702c075cd281fd0d85ae), [3](https://nlohmann.github.io/json/classnlohmann_1_1basic__json_aeffd70f622f8f2a51fd3d95af64b63a7.html#aeffd70f622f8f2a51fd3d95af64b63a7), [4](https://nlohmann.github.io/json/classnlohmann_1_1basic__json_aa8dca2e91a6301c36890f844e64f0023.html#aa8dca2e91a6301c36890f844e64f0023)) for more information. Note that contiguous storage cannot be checked at compile time; if any of the parse functions are called with a noncompliant container, the behavior is undefined and will most likely yield segmentation violation. The preconditions are enforced by an assertion unless the library is compiled with preprocessor symbol `NDEBUG`.
- As a general remark on **assertions**: The library uses assertions to preclude undefined behavior. A [prominent example](https://github.com/nlohmann/json/issues/289) for this is the `operator[]` for const JSON objects. The behavior of this const version of the operator is undefined if the given key does not exist in the JSON object, because unlike the non-const version, it cannot add a `null` value at the given key. Assertions can be switched of by defining the preprocessor symbol `NDEBUG`. See the [documentation of `assert`](http://en.cppreference.com/w/cpp/error/assert) for more information.
- In the course of cleaning up the parser/deserialization functions, the constructor [`basic_json(std::istream&, const parser_callback_t)`](https://nlohmann.github.io/json/classnlohmann_1_1basic__json_a32350263eb105764844c5a85e156a255.html#a32350263eb105764844c5a85e156a255) has been **deprecated** and will be deleted with the next major release 3.0.0 to unify the interface of the library. Deserialization will be done by stream operators or by calling one of the `parse` functions. That is, calls like `json j(i);` for an input stream `i` need to be replaced by `json j = json::parse(i);`. Compilers will produce a deprecation warning if client code uses this function.
- Minor improvements:
- Improved the performance of the serialization by avoiding the re-creation of a locale object.
- Fixed two MSVC warnings. Compiling the test suite with `/Wall` now only warns about non-inlined functions (C4710) and the deprecation of the constructor from input-stream (C4996).
- Some project internals:
- <img align="right" src="https://bestpractices.coreinfrastructure.org/assets/questions_page_badge-17b338c0e8528d695d8676e23f39f17ca2b89bb88176370803ee69aeebcb5be4.png"> The project has qualified for the [Core Infrastructure Initiative Best Practices Badge](https://bestpractices.coreinfrastructure.org/projects/289). While most requirements where already satisfied, some led to a more explicit documentation of quality-ensuring procedures. For instance, static analysis is now executed with every commit on the build server. Furthermore, the [contribution guidelines document](https://github.com/nlohmann/json/blob/develop/.github/CONTRIBUTING.md) how to communicate security issues privately.
- The test suite has been overworked and split into several files to allow for faster compilation and analysis. The execute the test suite, simply execute `make check`.
- The continuous integration with [Travis](https://travis-ci.org/nlohmann/json) was extended with Clang versions 3.6.0 to 3.8.1 and now includes 18 different compiler/OS combinations.
- An 11-day run of [American fuzzy lop](http://lcamtuf.coredump.cx/afl/) checked 962 million inputs on the parser and found no issue.

- Release date: 2016-07-31
- SHA-256: 8e97b7965b4594b00998d6704465412360e1a0ed927badb51ded8b82291a8f3d

Summary

This release combines a lot of small fixes and improvements. The release is backwards compatible.

Changes
- The **parser** has been overworked, and a lot of small issues have been fixed:
- Improved parser performance by avoiding recursion and using move semantics for the return value.
- Unescaped control charaters `\x10`-`\x1f` are not accepted any more.
- Fixed a bug in the parser when reading from an input stream.
- Improved test case coverage for UTF-8 parsing: now, all valid Unicode code points are tested both escaped and unescaped.
- The precision of output streams is now preserved by the parser.
- Started to check the **code correctness** by proving termination of important loops. Furthermore, individual assertions have been replaced by a more systematic function which checks the class invariants. Note that assertions should be switched off in production by defining the preprocessor macro `NDEBUG`, see the [documentation of `assert`](http://en.cppreference.com/w/cpp/error/assert).
- A lot of **code cleanup**: removed unused headers, fixed some compiler warnings, and fixed a build error for Windows-based Clang builds.
- Added some compile-time checks:
- Unsupported compilers are rejected during compilation with an `error` command.
- Static assertion prohibits code with incompatible pointer types used in `get_ptr()`.
- Improved the [documentation](https://nlohmann.github.io/json/), and adjusted the documentation script to choose the correct version of `sed`.
- Replaced a lot of "raw loops" by STL functions like `std::all_of`, `std::for_each`, or `std::accumulate`. This facilitates reasoning about termination of loops and sometimes allowed to simplify functions to a single return statement.
- Implemented a `value()` function for JSON pointers (similar to `at` function).
- The Homebrew formula (see [Integration](https://github.com/nlohmann/json#integration)) is now tested for all Xcode builds (6.1 - 8.x) with Travis.
- Avoided output to `std::cout` in the test cases.

- Release date: 2016-06-28
- SHA-256: ef550fcd7df572555bf068e9ec4e9d3b9e4cdd441cecb0dcea9ea7fd313f72dd

Summary

This release fixes a performance regression in the JSON serialization (function `dump()`). This fix is backwards compatible.

Changes
- The locale of the output stream (or the internal string stream if a JSON value is serialized to a string) is now adjusted once for the whole serialization instead of for each floating-point number.
- The locale of an output stream is now correctly reset to the previous value by the JSON library.

- Release date: 2016-06-24
- SHA-256: ac9e1fb25c2ac9ca5fc501fcd2fe3281fe04f07018a1b48820e7b1b11491bb6c

Summary

This release adds several features such as JSON Pointers, JSON Patch, or support for 64 bit unsigned integers. Furthermore, several (subtle) bugs have been fixed.

As `noexcept` and `constexpr` specifier have been added to several functions, the public API has effectively been changed in a (potential) non-backwards compatible manner. As we adhere to [Semantic Versioning](http://semver.org), this calls for a new major version, so say hello to 2️⃣.0️⃣.0️⃣.

Changes
- 🔟 A JSON value now uses `uint64_t` (default value for template parameter `NumberUnsignedType`) as data type for **unsigned integer** values. This type is used automatically when an unsigned number is parsed. Furthermore, constructors, conversion operators and an `is_number_unsigned()` test have been added.
- 👉 **JSON Pointer** ([RFC 6901](https://tools.ietf.org/html/rfc6901)) support: A JSON Pointer is a string (similar to an XPath expression) to address a value inside a structured JSON value. JSON Pointers can be used in `at()` and `operator[]` functions. Furthermore, JSON values can be “flattened” to key/value pairs using `flatten()` where each key is a JSON Pointer. The original value can be restored by “unflattening” the flattened value using `unflatten()`.
- 🏥 **JSON Patch** ([RFC 6902](https://tools.ietf.org/html/rfc6902)) support. A JSON Patch is a JSON value that describes the required edit operations (add, change, remove, …) to transform a JSON value into another one. A JSON Patch can be created with function `diff(const basic_json&)` and applied with `patch(const basic_json&)`. Note the created patches use a rather primitive algorithm so far and leave room for improvement.
- 🇪🇺 The code is now **locale-independent**: Floating-point numbers are always serialized with a period (`.`) as decimal separator and ignores different settings from the locale.
- 🍺 **Homebrew** support: Install the library with `brew tap nlohmann/json && brew install nlohmann_json`.
- Added constructor to create a JSON value by parsing a `std::istream` (e.g., `std::stringstream` or `std::ifstream`).
- Added **`noexcept`** specifier to `basic_json(boolean_t)`, `basic_json(const number_integer_t)`, `basic_json(const int)`, `basic_json(const number_float_t)`, iterator functions (`begin()`, `end()`, etc.)
- When parsing numbers, the sign of `0.0` (vs. `-0.0`) is preserved.
- Improved MSVC 2015, Android, and MinGW support. See [README](https://github.com/nlohmann/json#supported-compilers) for more information.
- Improved test coverage (added 2,225,386 tests).
- Removed some misuses of `std::move`.
- Fixed several compiler warnings.
- Improved error messages from JSON parser.
- Updated to [`re2c`](http://re2c.org) to version 0.16 to use a minimal DFAs for the lexer.
- Updated test suite to use [Catch](https://github.com/philsquared/Catch) version 1.5.6.
- Made type getters (`is_number`, etc.) and const value access `constexpr`.
- Functions `push_back` and `operator+=` now work with key/value pairs passed as initializer list, e.g. `j_object += {"key", 1}`.
- Overworked `CMakeLists.txt` to make it easier to integrate the library into other projects.

Notes
- Parser error messages are still very vague and contain no information on the error location.
- The implemented `diff` function is rather primitive and does not create minimal diffs.
- The name of function `iteration_wrapper` may change in the future and the function will be deprecated in the next release.
- Roundtripping (i.e., parsing a JSON value from a string, serializing it, and comparing the strings) of floating-point numbers is not 100% accurate. Note that [RFC 7159](https://tools.ietf.org/html/rfc7159) defines no format to internally represent numbers and states not requirement for roundtripping. Nevertheless, benchmarks like [Native JSON Benchmark](https://github.com/miloyip/nativejson-benchmark) treat roundtripping deviations as conformance errors.

- Release date: 2016-01-24
- SHA-256: c0cf0e3017798ca6bb18e757ebc570d21a3bdac877845e2b9e9573d183ed2f05

Summary

This release fixes several small bugs and adds functionality in a backwards-compatible manner. Compared to the [last version (1.0.0)](https://github.com/nlohmann/json/releases/tag/v1.0.0), the following changes have been made:

Changes
- _Fixed_: **Floating-point numbers** are now serialized and deserialized properly such that rountripping works in more cases. [185, 186, 190, 191, 194]
- _Added_: The code now contains **assertions** to detect undefined behavior during development. As the standard function `assert` is used, the assertions can be switched off by defining the preprocessor symbol `NDEBUG` during compilation. [168]
- _Added_: It is now possible to get a **reference** to the stored values via the newly added function `get_ref()`. [128, 184]
- _Fixed_: Access to object values via keys (**`operator[]`**) now works with all kind of string representations. [171, 189]
- _Fixed_: The code now compiles again with **Microsoft Visual Studio 2015**. [144, 167, 188]
- _Fixed_: All required headers are now included.
- _Fixed_: Typos and other small issues. [162, 166, 175, 177, 179, 180]

Notes

There are still known open issues (178, 187) which will be fixed in version 2.0.0. However, these fixes will require a small API change and will not be entirely backwards-compatible.