Files
json/docs
Niels Lohmann 993e37e7ec Reduce test compile times (spike)
Two changes roughly halve the CPU time needed to build the unit tests
(clang 21: ~300 s -> ~150 s, GCC 16: ~750-820 s -> ~395-420 s, Debug):

- Move the C++14/17/20-dependent tests into separate
  unit-<name>-cpp<N>.cpp files. A test file is built for every standard
  whose JSON_HAS_CPP_<N> macro it mentions, so far whole large files were
  rebuilt for C++14/17/20 because of a few #ifdef sections. The main files
  are now built for C++11 only; the ci_test_*_cxx<N> jobs still build
  every file for every standard.

- Add the CMake option JSON_TestUnityBuild (ON by default, OFF with
  MinGW): compatible test files are compiled in batches as one
  translation unit so they share the template instantiations of the
  library. Each file keeps its own CTest test, which runs the batch
  executable filtered to that file's test cases. The binary-format tests
  form an explicit group; the rest is batched by JSON_TestUnityBatchSize.

Fix the name clashes that merging files exposed, document the rules for
test files in tests/README.md, and point CONTRIBUTING.md to it.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-09 16:49:45 +02:00
..
2026-10-09 16:49:45 +02:00
2025-04-11 10:41:14 +02:00
2025-04-11 10:41:14 +02:00

Documentation

Generate documentation

Note on documentation: The source files contain links to the online documentation at https://json.nlohmann.me.
This URL provides the most recent documentation and also applies to previous versions. Documentation for deprecated functions is not removed; instead, it is marked as deprecated.

If you want to view the documentation for a specific tag or commit hash, you can generate it locally as follows (example using tag v3.10.2):

git clone https://github.com/nlohmann/json.git
cd json
git checkout v3.10.2
make install_venv serve -C docs/mkdocs

Open http://127.0.0.1:8000/ in your browser. Replace any URL in the source code that points to https://json.nlohmann.me with http://127.0.0.1:8000 to view the documentation for the selected tag or commit hash.