Ensure that rustc and other dependencies are installed before building a rust project

[aqueenan]

🐛 Bug Report

wrangler build produces an unhelpful error message when rustc isn't in the path.

Environment

• operating system:

Microsoft Windows [Version 10.0.18362.295]
Command Prompt and Bash has the same problem though.

• output of rustc -V:

'rustc' is not recognized as an internal or external command,
operable program or batch file.

• output of node -v:

v8.11.3

• output of wrangler -V:

 wrangler 1.1.1

Steps to reproduce

I installed wrangler using npm, and created a rust project, then called wrangler build.

What did you expect to see?

Either a successful build, or a helpful error message prompting me to use rustup to install rustc and the dependencies.

What did you see instead?

When I called wrangler build I got the error:

>wrangler build
⬇️ Installing wasm-pack...
 Compiling your project to WebAssembly...
Error: The system cannot find the file specified. (os error 2)
Error: failed to execute `"cmd" "/C" "...\\AppData\\Local\\.wrangler\\wasm-pack-7824e3bac6af138a\\wasm-pack.exe" "build" "--target" "no-modules"`: exited with exit code: 1

The underlying issue is that wasm-pack doesn't return a helpful error either, just an exit code.

[ashleymichal]

for someone looking to pick up an issue, this should be easy enough to check in the build module using which

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.