Why is Rust code completion not working in my Visual Studio 2015?

Question

I'm using Visual Studio 2015 v14 with VisualRust 0.1.2

Under Tools -> Options -> Text Editor -> Visual Rust statement completion is greyed out and cannot be enabled.

Under Tools -> Options -> Visual Rust I have selected Use bundled racer and Read rust sources from environment variable

The racer that came bundled with VisualRust works correctly when called manually, that is racer-120e98b.exe complete std::io:: returns the relevant results.

In Visual Studio, writing let e = std::io:: and then pressing CTRL + Space to trigger autocompletion will only return a list of the reserved keywords (such as if, while, struct, etc).

I'm guessing that the problem is that statement completion can't be turned on. How do I solve this?

Answer 1

I run Visual Studio 2015 Community, and this is how I did it:

Download the racer and the rust sources via

cargo install racer
rustup component add rust-src

However, the RUST_SRC_PATH variable is not yet set, and I do not know who is supposed to set it. The following batch script will set the variable to its correct value, see this issue on github.

@ECHO OFF
FOR /F "tokens=* USEBACKQ" %%P IN (`rustc --print sysroot`) DO SET RS=%%P
SETX RUST_SRC_PATH "%RS%\lib\rustlib\src\rust\src"

After this, I still had to specify the path to racer.exe manually instead of the Use bundled racer option. By default, you can find it here:

%USERPROFILE%\.cargo\bin\racer.exe

Hope it helps!