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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
use serde::{Deserialize, Deserializer};
#[derive(Clone, Debug, PartialEq, Eq)]
pub(crate) struct NonEmptyString(String);
impl NonEmptyString {
pub(crate) fn new(value: impl Into<String>) -> Option<Self> {
let value = value.into();
match value.trim() {
"" => None,
trimmed if trimmed.len() == value.len() => Some(Self(value)),
trimmed => Some(Self(trimmed.to_owned())),
}
}
pub(crate) fn deserialize_option<'de, D: Deserializer<'de>>(
deserializer: D,
) -> Result<Option<Self>, D::Error> {
Ok(Option::<String>::deserialize(deserializer)?.and_then(Self::new))
}
}
impl AsRef<str> for NonEmptyString {
fn as_ref(&self) -> &str {
&self.0
}
}
impl From<NonEmptyString> for String {
fn from(value: NonEmptyString) -> Self {
value.0
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn trims_and_rejects_blank_strings() {
assert_eq!(NonEmptyString::new(""), None);
assert_eq!(NonEmptyString::new(" \t\n"), None);
assert_eq!(
NonEmptyString::new(" Firefox/140.0 ").unwrap().as_ref(),
"Firefox/140.0"
);
}
}