#[cfg(feature = "suggestions")]
use strsim;
use fmt::Format;
#[cfg(feature = "suggestions")]
#[cfg_attr(feature = "lints", allow(needless_lifetimes))]
pub fn did_you_mean<'a, T, I>(v: &str, possible_values: I) -> Option<&'a str>
where T: AsRef<str> + 'a,
I: IntoIterator<Item = &'a T>
{
let mut candidate: Option<(f64, &str)> = None;
for pv in possible_values.into_iter() {
let confidence = strsim::jaro_winkler(v, pv.as_ref());
if confidence > 0.8 &&
(candidate.is_none() || (candidate.as_ref().unwrap().0 < confidence)) {
candidate = Some((confidence, pv.as_ref()));
}
}
match candidate {
None => None,
Some((_, candidate)) => Some(candidate),
}
}
#[cfg(not(feature = "suggestions"))]
pub fn did_you_mean<'a, T, I>(_: &str, _: I) -> Option<&'a str>
where T: AsRef<str> + 'a,
I: IntoIterator<Item = &'a T>
{
None
}
#[cfg_attr(feature = "lints", allow(needless_lifetimes))]
pub fn did_you_mean_suffix<'z, T, I>(arg: &str,
values: I,
style: DidYouMeanMessageStyle)
-> (String, Option<&'z str>)
where T: AsRef<str> + 'z,
I: IntoIterator<Item = &'z T>
{
match did_you_mean(arg, values) {
Some(candidate) => {
let mut suffix = "\n\tDid you mean ".to_owned();
match style {
DidYouMeanMessageStyle::LongFlag =>
suffix.push_str(&*format!("{}", Format::Good("--"))),
DidYouMeanMessageStyle::EnumValue => suffix.push('\''),
}
suffix.push_str(&Format::Good(candidate).to_string()[..]);
if let DidYouMeanMessageStyle::EnumValue = style {
suffix.push('\'');
}
suffix.push_str(" ?");
(suffix, Some(candidate))
}
None => (String::new(), None),
}
}
pub enum DidYouMeanMessageStyle {
LongFlag,
EnumValue,
}
#[cfg(all(test, features = "suggestions"))]
mod test {
use super::*;
#[test]
fn did_you_mean_possible_values() {
let p_vals = ["test", "possible", "values"];
assert_eq!(did_you_mean("tst", p_vals.iter()), Some("test"));
assert!(did_you_mean("hahaahahah", p_vals.iter()).is_none());
}
}