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// 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())
);
}
}
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