Cannot run tests using cargo_pup_lint_config

[tomas-janecka-tfs]

Description

I am trying to run architecture tests using cargo_pup_lint_config library and cargo test . No matter what I am presented with the error:

error: no bin target named `cargo-pup` in default-run packages
thread '<thread_name>' (37792) panicked at C:\Users\<user>\.cargo\registry\src\index.crates.io-1949cf8c6b5b557f\cargo_pup_lint_config-0.1.7\src\lint_builder_ext.rs:136:13:
cargo pup checks failed!

Preconditions

• Folder cargo_pup_lint_config-0.1.7 is removed from C:\Users\<user>\.cargo\registry\src\index.crates.io-1949cf8c6b5b557f so it rebuilds before running test

Steps to reproduce issue

1. cargo new project
2. cargo add cargo_pup_lint_config --dev
3. ui.rs

use std::fs;

pub fn ui_stuff() {
    let file_path = "config.toml";
    let _ = fs::read_to_string(file_path).map_err(|e| format!("Failed to read config file: {}", e));
}

4. main.rs

mod ui;

fn main() {
    ui::ui_stuff();
}

5. architecture_tests.rs

use cargo_pup_lint_config::{LintBuilder, LintBuilderExt, ModuleLintExt, Severity};

#[test]
fn ui_does_not_depend_on_fs() {
    let mut builder = LintBuilder::new();

    builder
        .module_lint()
        .lint_named("ui_does_not_depend_on_fs")
        .matching(|m| m.module(".*ui.*"))
        .with_severity(Severity::Error)
        .restrict_imports(
            None,
            Some(vec![".*fs.*".to_string()])
        )
        .build();

    builder
        .assert_lints(None)
        .expect("UI modules should not depend on filesystem modules");
}

6. cargo test

Expected behavior

error: Use of module 'std::fs' is denied
 --> src\ui.rs:1:1
  |
1 | use std::fs;
  | ^^^^^^^^^^^^
  |
  = help: Remove this import
  = note: Applied by cargo-pup rule 'ui_does_not_depend_on_fs'.
  = note: `#[deny(module_restrict_imports)]` on by default

Actual behavior

error: no bin target named `cargo-pup` in default-run packages
thread '<thread_name>' (37792) panicked at C:\Users\<user>\.cargo\registry\src\index.crates.io-1949cf8c6b5b557f\cargo_pup_lint_config-0.1.7\src\lint_builder_ext.rs:136:13:
cargo pup checks failed!

Environment

• Windows 11
• rustc -Vv

rustc 1.94.1 (e408947bf 2026-03-25)
binary: rustc
commit-hash: e408947bfd200af42db322daf0fadfe7e26d3bd1
commit-date: 2026-03-25
host: x86_64-pc-windows-msvc
release: 1.94.1
LLVM version: 21.1.8

• cargo_pup_lint_config = "0.1.7"

Proposed fix

I used AI to diagnose and find the error. It proposed this to fix the error and it works.
lint_builder_ext.rs - https://github.com/DataDog/cargo-pup/blob/main/cargo_pup_lint_config/src/lint_builder_ext.rs

// ...
// Line 225
// Before
Ok(current_dir)
// After
anyhow::bail!("Failed to find cargo-pup workspace root");
// ...