Coverage for ci/build-rust.py: 23%

1# This is a script to generate the `wasmtime/bindgen/generated` directory. That 

2# directory itself exposes the Python-based functionality for generating 

3# bindings itself, so a bit of a bootstrapping process happens here. 

4# 

5# Bindings generation itself is written in Rust since that's where all of the 

6# `*.wit` tooling is located. That's compiled to a `bindgen.wasm` file and then 

7# assembled into a `component.wasm` using the `bindgen.wit` world. 

8# 

9# From this compiled component we sort of need to run it on itself. To avoid 

10# that odd bootstrapping problem we work around that by running the bindgen 

11# on the native platform, on the component, to generate bindings. That 

12# is then loaded here and re-executed, through wasm, to ensure that everything 

13# remains the same. 

14 

15import subprocess 

16 

17 

18def main(): 

19 print('======================= Building bindgen.wasm =====================') 

20 

21 subprocess.run( 

22 ['cargo', 'build', '--release', '--target=wasm32-wasip1', '-p=bindgen'], 

23 cwd='rust' 

24 ).check_returncode() 

25 

26 core = 'rust/target/wasm32-wasip1/release/bindgen.wasm' 

27 wasi = 'ci/wasi_snapshot_preview1.reactor.wasm' 

28 component = 'rust/target/component.wasm' 

29 

30 print('======================= Building component.wasm ===================') 

31 

32 subprocess.run( 

33 ['wasm-tools', 'component', 'new', core, '--adapt', f'wasi_snapshot_preview1={wasi}', '-o', component], 

34 ).check_returncode() 

35 

36 print('======================= Bootstrapping with native platform ========') 

37 

38 subprocess.run( 

39 ['cargo', 'run', '-p=bindgen', '--features=cli', 'target/component.wasm', '../wasmtime/bindgen/generated'], 

40 cwd='rust' 

41 ).check_returncode() 

42 

43 

44if __name__ == '__main__': 

45 main()