VS Code snippet

read.rs

#[allow(dead_code)]
fn read<T: std::str::FromStr>() -> Option<T> {
    let mut b = String::new();
    std::io::stdin().read_line(&mut b).ok();
    b.trim().parse().ok()
}

/// # Examples
/// ```
/// let mtx = (0..2).map(|_| read_v().unwrap()).collect();
/// ```
#[allow(dead_code)]
fn read_v<T: std::str::FromStr>() -> Option<Vec<T>> {
    read::<String>()
        .unwrap()
        .split_whitespace()
        .map(|e| e.parse().ok())
        .collect()
}

rust.rs

{
	// Place your snippets for rust here. Each snippet is defined under a snippet name and has a prefix, body and
	// description. The prefix is what is used to trigger the snippet and the body will be expanded and inserted. Possible variables are:
	// $1, $2 for tab stops, $0 for the final cursor position, and ${1:label}, ${2:another} for placeholders. Placeholders with the
	// same ids are connected.
	"scan and solve": {
		"prefix": "scanner",
		"body": [
			"use std::io::stdin;",
			"",
			"#[allow(unused_macros)]",
			"macro_rules! read {",
			"    ($(\\$t:ty), *) => {",
			"        {",
			"            let mut line: String = String::new();",
			"            stdin().read_line(&mut line).unwrap();",
			"            let mut iter = line.split_whitespace();",
			"            (",
			"                $(iter.next().unwrap().parse::<\\$t>().unwrap(),)*",
			"            )",
			"        }",
			"    };",
			"    (\\$t:ty;) => {",
			"        {",
			"            let mut line: String = String::new();",
			"            stdin().read_line(&mut line).unwrap();",
			"            let iter = line.split_whitespace();",
			"            iter",
			"                .map(|t| t.parse::<\\$t>().unwrap())",
			"                .collect::<Vec<_>>()",
			"        }",
			"    };",
			"}",
			"",
			"fn main() {",
			"    let (n,) = read!(i32);",
			"    println!(\"{}\", solve(n));",
			"}",
			"",
			"fn solve<T>(x: T) -> T {",
			"    x",
			"}",
			"",
			"#[cfg(test)]",
			"mod tests {",
			"    #[allow(unused_imports)]",
			"    use super::*;",
			"",
			"    #[test]",
			"    fn it_works() {",
			"        assert_eq!(solve(42), 42);",
			"    }",
			"}"
		],
		"description": "Read, Solve, Print, and Test."
	}
}

test.rs

#[cfg(test)]
mod tests {
    #[allow(unused_imports)]
    use super::*;

    #[test]
    fn parse() {
        assert_eq!(1, 1);
    }
}

ref. https://qiita.com/hatoo@github/items/fa14ad36a1b568d14f3e

cf. https://qiita.com/koji-cw/items/0cce3b075faffe5e50ed#whiteread