trailofbits / dylint

Hello,

I'm writing a dylint rule which checks for a specific function call derived from an external trait. I'm getting an unresolved import error when using an external crate in my tests.

Here's the test I'm writing (paraphrased)

# ui/main.rs
use serde::{Deserialize, Serialize};

#[derive(Debug, Deserialize, Serialize)]
struct Test {
    a: u32,
    b: u64,
}

fn main() {}

When I run cargo test I get:

error[E0432]: unresolved import `serde`
  --> $DIR/main.rs:1:5
   |
LL | use serde::{Deserialize, Serialize};
   |     ^^^^^ maybe a missing crate `serde`?
   |
   = help: consider adding `extern crate serde` to use the `serde` crate

I've looked at your examples, and used extern crate but was unable to get it to work.

Is there a way to use external crates in tests?

Hi, @R9295. Does your test use dylint_testing::ui_test_example? If so, then it should be possible to declare external crates as dev-dependencies. For comparison, here is a lint that uses anyhow in this way:

dylint/examples/restriction/misleading_variable_name/Cargo.toml

Lines 12 to 14 in 43816b7

    
           [[example]] 
        
           name = "ui" 
        
           path = "ui/main.rs"

dylint/examples/restriction/misleading_variable_name/Cargo.toml

Lines 23 to 24 in 43816b7

    
           [dev-dependencies] 
        
           anyhow = "1.0"

dylint/examples/restriction/misleading_variable_name/src/lib.rs

Lines 284 to 287 in 43816b7

    
           #[test] 
        
           fn ui() { 
        
               dylint_testing::ui_test_example(env!("CARGO_PKG_NAME"), "ui"); 
        
           }

Ahhh, I was using the default dylint_testing::ui_test instead of ui_test_example.

Thanks for the quick response. Feel free to close the issue

This is good feedback. Thank you.

I will try to make mention of ui_test_example more prominent in the documentation.

Cheers.

	#[test]
	fn ui() {
	dylint_testing::ui_test_example(env!("CARGO_PKG_NAME"), "ui");
	}

unresolved import when using external crate in tests