The `tree-sitter-loader` crate currently always pulls
`tree-sitter-highlight` and `tree-sitter-tags` as dependencies.
However, apart from the tree-sitter CLI, most clients will not need both
of these libraries.
This commit makes the dependencies optional, but still includes them by
default in order not to break the backward compatibility.
This allows users to build parsers without having to run `test` or
`parse` to invoke the compilation process, and allows them to output the
object file to wherever they like. The `build-wasm` command was merged
into this by just specifying the `--wasm` flag.
For some reason, the linker seems to behave a bit differently with `-exported_symbols_list` on macOS vs other operating systems, so we'll disable this for now
C++ has been a headache to deal with throughout the ecosystem and for
several downstream projects. It is difficult to get working with WASM,
and induces potential issues with compilation on Windows. It has been
proven that writing scanners in C is a much better alternative, and is
the recommended way to write scanners now. C++ support will likely be
removed in 0.21.0
Previously, `tree-sitter build-wasm` had the ability to build WASM
by using docker to pull in an image with a complete emscripten toolchain.
This commit adds the ability to use podman to do the same thing.
Using podman requires two notable changes:
1. Using the fully-qualified image name. Docker defaults to prepending
`docker.io` to the image name, but podman does not.
2. Podman will mount the `/src/` volume as belonging to root unless
`--userns=keep-id` is passed. I think podman's different
volume-ownership is related to podman's daemonless execution and
`--uidmap` functionality, but I'm not 100% sure.
To test, I ran
```sh
script/fetch-fixtures
script/generate-fixtures
script/generate-fixtures-wasm # <- the important one!
```
which worked as well as the docker version.
