How to debug Rust unit tests on Windows?

Question

I\'m developing code for the Codingame problems using VS Code on Windows with Rust and the Visual Studio toolchain.

I have found multiple guides explaining how to de

Answer 1

Rust unit tests are compiled as separate binaries, which means you debug them exactly the same as any other binary. Once compiled, they are located at ./target/debug/$name-$hash.

Visual Studio Code

Here's modified versions of the VS Code configuration files that allow me to debug a unit test.

tasks.json

{
    "type": "shell",
    "label": "cargo test build",
    "command": "cargo",
    "args": [
        "test", "--no-run"
    ],
    "problemMatcher": [
        "$rustc"
    ]
}

launch.json

{
    "name": "Run Test Debugger",
    "type": "cppvsdbg",
    "request": "launch",
    "program": "${workspaceFolder}/target/debug/buggin-70708b3916187eeb.exe",
    "args": [],
    "stopAtEntry": false,
    "cwd": "${workspaceFolder}",
    "environment": [],
    "externalConsole": true,
    "preLaunchTask": "cargo test build",
}

Working

Windbg

Build your tests:

cargo test --no-run

Open the built executable in Windbg and open the source file.

---

Finding the hash is the most annoying aspect. The best solution I know of is to write a small script that builds the tests and then finds the test executable based on which is newest. My Powershell skills are not adequate to the task, nor do I know how to directly integrate this with VS Code or Windbg.

There are open issues for Cargo to help with identifying the file:

• produce deterministic filenames for build --test and test --no-run (#1924)
• Make it possible to run binaries produced by cargo directly (#3670)