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// Internal
use crate::{app::App, fmt::Format};
/// Produces a string from a given list of possible values which is similar to
/// the passed in value `v` with a certain confidence.
/// Thus in a list of possible values like ["foo", "bar"], the value "fop" will yield
/// `Some("foo")`, whereas "blark" would yield `None`.
#[cfg(feature = "suggestions")]
#[cfg_attr(feature = "cargo-clippy", allow(clippy::needless_lifetimes))]
pub fn did_you_mean<'a, T: ?Sized, 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 {
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: ?Sized, I>(_: &str, _: I) -> Option<&'a str>
where
T: AsRef<str> + 'a,
I: IntoIterator<Item = &'a T>,
{
None
}
/// Returns a suffix that can be empty, or is the standard 'did you mean' phrase
pub fn did_you_mean_flag_suffix<'z, T, I>(
arg: &str,
args_rest: &'z [&str],
longs: I,
subcommands: &'z [App],
) -> (String, Option<&'z str>)
where
T: AsRef<str> + 'z,
I: IntoIterator<Item = &'z T>,
{
if let Some(candidate) = did_you_mean(arg, longs) {
let suffix = format!(
"\n\tDid you mean {}{}?",
Format::Good("--"),
Format::Good(candidate)
);
return (suffix, Some(candidate));
}
subcommands
.iter()
.filter_map(|subcommand| {
let opts = subcommand
.p
.flags
.iter()
.filter_map(|f| f.s.long)
.chain(subcommand.p.opts.iter().filter_map(|o| o.s.long));
let candidate = match did_you_mean(arg, opts) {
Some(candidate) => candidate,
None => return None,
};
let score = match args_rest.iter().position(|x| *x == subcommand.get_name()) {
Some(score) => score,
None => return None,
};
let suffix = format!(
"\n\tDid you mean to put '{}{}' after the subcommand '{}'?",
Format::Good("--"),
Format::Good(candidate),
Format::Good(subcommand.get_name())
);
Some((score, (suffix, Some(candidate))))
})
.min_by_key(|&(score, _)| score)
.map(|(_, suggestion)| suggestion)
.unwrap_or_else(|| (String::new(), None))
}
/// Returns a suffix that can be empty, or is the standard 'did you mean' phrase
pub fn did_you_mean_value_suffix<'z, T, I>(arg: &str, values: I) -> (String, Option<&'z str>)
where
T: AsRef<str> + 'z,
I: IntoIterator<Item = &'z T>,
{
match did_you_mean(arg, values) {
Some(candidate) => {
let suffix = format!("\n\tDid you mean '{}'?", Format::Good(candidate));
(suffix, Some(candidate))
}
None => (String::new(), None),
}
}
#[cfg(all(test, features = "suggestions"))]
mod test {
use super::*;
#[test]
fn possible_values_match() {
let p_vals = ["test", "possible", "values"];
assert_eq!(did_you_mean("tst", p_vals.iter()), Some("test"));
}
#[test]
fn possible_values_nomatch() {
let p_vals = ["test", "possible", "values"];
assert!(did_you_mean("hahaahahah", p_vals.iter()).is_none());
}
#[test]
fn suffix_long() {
let p_vals = ["test", "possible", "values"];
let suffix = "\n\tDid you mean \'--test\'?";
assert_eq!(
did_you_mean_flag_suffix("tst", p_vals.iter(), []),
(suffix, Some("test"))
);
}
#[test]
fn suffix_enum() {
let p_vals = ["test", "possible", "values"];
let suffix = "\n\tDid you mean \'test\'?";
assert_eq!(
did_you_mean_value_suffix("tst", p_vals.iter()),
(suffix, Some("test"))
);
}
}