Don't convert boolean enums unless JSON compatibility is requested

[axelboc]

H5Web supports plotting boolean datasets:

Currently, h5wasm converts boolean enum arrays, which are read as numeric typed arrays by the HDF5 library, to plain JS boolean arrays. This means that in H5Web, I have to convert those boolean arrays back to numeric arrays before I can plot them.

In this PR, I'm proposing to no longer convert boolean enum arrays when json_compatible is false - i.e. to convert them only when JSON-compatible data is requested.

[axelboc]

Sorry for the spam, I'm struggling to run the tests locally. Also, the typed array returned by HDF5 lib depends on the enum type's underlying base type, which seems to be int8 and not uint8 for files written with h5py.

[bmaranville]

To run tests locally, you can use a conda environment (specifically using conda-forge):

mamba create -n h5wasm -c conda-forge --override-channels nodejs emsdk make cmake
mamba activate h5wasm
emsdk install 3.1.46
emsdk activate 3.1.46
#  follow instructions that are printed from the "activate" command to add emscripten paths, e.g.
#  source "/Users/bbm/mambaforge/envs/h5wasm/lib/python3.12/site-packages/emsdk/emsdk_env.sh"
make
npm i
npm run build
npm test

the emscripten compile will be a little slow the first time, because it's compiling and caching a bunch of system libraries.

[bmaranville]

For your changes in this PR, you will only need to run make once, since you're only touching the .ts files.

[axelboc]

Thanks, what's weird is that I already have a working environment that allows me to run make and npm run build without issue. It's when I run npm test (from the root of the repo) that things go AWOL. HDF5 complains that it can't open any of the test files:

 #007: /__w/libhdf5-wasm/libhdf5-wasm/build/1.14.2/_deps/hdf5-src/src/H5FDsec2.c line 326 in H5FD__sec2_open(): unable to open file: name = 'test/empty.h5', errno = 44, error message = 'No such file or directory', flags = 0, o_flags = 0

The files do exist, obviously, so not sure what's going on.

[axelboc]

Ah all good, I had made changes to CMakeList.txt a while back when investigating something (can't remember what). Anyway, reverting and running make && npm run build fixed it. Sorry for the bother.

[bmaranville]

Is this one ready for review?

[axelboc]

Yep, sorry :)

[bmaranville]

Since I think your team requested the conversion to boolean in the first place, I'm happy to make this subtle change; if you wouldn't mind adding a note to the CHANGELOG.md indicating the new behavior I'd appreciate it. (feel free to add a section for v0.7.6 - we can change the version number later if breaking metadata changes are included into something like v0.8.0)

[axelboc]

No worries, done!