How to import functions from another file in Rust?

I have the following Rust project:

./
├── Cargo.lock
├── Cargo.toml
├── src
│   ├── Easy
│   │   ├── 001_Two_Sum.rs
│   │   ├── 083_Remove_Duplicates_from_Sorted_List.rs
│   │   └── bin
│   ├── lib.rs
│   └── utils
│       ├── list_node
│       │   └── mod.rs
│       └── mod.rs
└── target

src/lib.rs

pub mod utils;
pub use crate::utils::list_node::ListNode;

src/utils/mod.rs

pub mod list_node;

src/utils/list_node/mod.rs

#[derive(PartialEq, Eq, Clone, Debug)]
pub struct ListNode {
  pub val: i32,
  pub next: Option<Box<ListNode>>
}

impl ListNode {
  #[inline]
  pub fn new(val: i32) -> Self {
    ListNode {
      next: None,
      val
    }
  }
}

src/Easy/083_Remove_Duplicates_from_Sorted_List.rs

struct Solution;

use crate::utils::list_node::ListNode;


impl Solution {
    pub fn delete_duplicates(head: Option<Box<ListNode>>) -> Option<Box<ListNode>> {
        let n = ListNode::new(1);       
    }
}

fn main() {
    println!("\nJob done!");
}

Cargo.toml

[package]
name = "leetcode"
version = "0.1.0"
edition = "2021"

[dependencies]
cargo-watch = "8.5.2"

[[bin]]
name = "001_Two_Sum"
path = "src/Easy/001_Two_Sum.rs"

[[bin]]
name = "083_Remove_Duplicates_from_Sorted_List"
path = "src/Easy/083_Remove_Duplicates_from_Sorted_List.rs"

I'm trying to use ListNode struct in 083_Remove_Duplicates_from_Sorted_List.rs file but I'm getting this error message:

failed to resolve: unresolved import
unresolved importrustc (Click for full compiler diagnostic)
083_Remove_Duplicates_from_Sorted_List.rs(3, 12): a similar path exists: `leetcode::utils`

If I use: use crate::leetcode::utils::list_node::ListNode;

I get this another error message:

failed to resolve: could not find `leetcode` in the crate root
could not find `leetcode` in the crate rootrustc (Click for full compiler diagnostic)

Previously I tried other configurations (found on Internet and suggested by IAs) but nothing seems to work.

I'm working on EndeveaourOS distro with VSCode. Any suggestion?

Edit 1:

Thanks to Carson's answer that error message was removed but I'm getting a new error when running the program:

error[E0433]: failed to resolve: maybe a missing crate `leetcode`?
 --> 021_Merge_Two_Sorted_Lists.rs:1:5
  |
1 | use leetcode::utils::list_node::ListNode;
  |     ^^^^^^^^ maybe a missing crate `leetcode`?
  |
  = help: consider adding `extern crate leetcode` to use the `leetcode` crate

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0433`.

I tried adding this line extern crate leetcode on program being run but I got this error:

error[E0463]: can't find crate for `leetcode`
 --> 021_Merge_Two_Sorted_Lists.rs:1:1
  |
1 | extern crate leetcode;
  | ^^^^^^^^^^^^^^^^^^^^^^ can't find crate

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0463`.

Edit 2:

The error message described in Edit 1 was caused by configuration of Code Runner extension. I changed this:

"rust": "cd $dir && rustc --out-dir bin $fileName && $dir/bin/$fileNameWithoutExt",

to this:

"rust": "cd $dir && cargo run --bin $fileNameWithoutExt --quiet",

Alternatively, I could use SHIFT+CTRL+B to run the local configuration defined in .vscode/tasks.json.

Solution

Change use crate::utils::... to use leetcode::utils::....

With your split lib, [[bin]] setup, you are defining three crates:

leetcode as defined in lib.rs
001_Two_Sum
083_Remove_Duplicates_from_Sorted_List

When you use crate:: inside 001_Two_Sum, crate refers to 001_Two_Sum, not leetcode.