9bdb0a12e4
Hints are now accessible using the CLI subcommand `rustlings hint <exercise name`. BREAKING CHANGE: This fundamentally changes the way people interact with exercises.
41 lines
1.2 KiB
Rust
41 lines
1.2 KiB
Rust
// errors1.rs
|
|
// This function refuses to generate text to be printed on a nametag if
|
|
// you pass it an empty string. It'd be nicer if it explained what the problem
|
|
// was, instead of just sometimes returning `None`. The 2nd test currently
|
|
// does not compile or pass, but it illustrates the behavior we would like
|
|
// this function to have.
|
|
// Execute `rustlings hint errors1` for hints!
|
|
|
|
pub fn generate_nametag_text(name: String) -> Option<String> {
|
|
if name.len() > 0 {
|
|
Some(format!("Hi! My name is {}", name))
|
|
} else {
|
|
// Empty names aren't allowed.
|
|
None
|
|
}
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod tests {
|
|
use super::*;
|
|
|
|
// This test passes initially if you comment out the 2nd test.
|
|
// You'll need to update what this test expects when you change
|
|
// the function under test!
|
|
#[test]
|
|
fn generates_nametag_text_for_a_nonempty_name() {
|
|
assert_eq!(
|
|
generate_nametag_text("Beyoncé".into()),
|
|
Some("Hi! My name is Beyoncé".into())
|
|
);
|
|
}
|
|
|
|
#[test]
|
|
fn explains_why_generating_nametag_text_fails() {
|
|
assert_eq!(
|
|
generate_nametag_text("".into()),
|
|
Err("`name` was empty; it must be nonempty.".into())
|
|
);
|
|
}
|
|
}
|