1 use app::App;
_is_char_boundary(&self, index: usize) -> bool2 // Third Party
3 #[cfg(feature = "suggestions")]
4 use strsim;
5
6 // Internal
_is_char_boundary(&self, index: usize) -> bool7 use fmt::Format;
8
9 /// Produces a string from a given list of possible values which is similar to
10 /// the passed in value `v` with a certain confidence.
11 /// Thus in a list of possible values like ["foo", "bar"], the value "fop" will yield
12 /// `Some("foo")`, whereas "blark" would yield `None`.
13 #[cfg(feature = "suggestions")]
14 #[cfg_attr(feature = "lints", allow(needless_lifetimes))]
15 pub fn did_you_mean<'a, T: ?Sized, I>(v: &str, possible_values: I) -> Option<&'a str>
16 where
17 T: AsRef<str> + 'a,
18 I: IntoIterator<Item = &'a T>,
19 {
20 let mut candidate: Option<(f64, &str)> = None;
21 for pv in possible_values {
22 let confidence = strsim::jaro_winkler(v, pv.as_ref());
23 if confidence > 0.8 && (candidate.is_none() || (candidate.as_ref().unwrap().0 < confidence))
24 {
25 candidate = Some((confidence, pv.as_ref()));
26 }
27 }
28 match candidate {
29 None => None,
30 Some((_, candidate)) => Some(candidate),
31 }
32 }
33
34 #[cfg(not(feature = "suggestions"))]
35 pub fn did_you_mean<'a, T: ?Sized, I>(_: &str, _: I) -> Option<&'a str>
36 where
37 T: AsRef<str> + 'a,
38 I: IntoIterator<Item = &'a T>,
39 {
40 None
41 }
42
43 /// Returns a suffix that can be empty, or is the standard 'did you mean' phrase
44 #[cfg_attr(feature = "lints", allow(needless_lifetimes))]
45 pub fn did_you_mean_flag_suffix<'z, T, I>(
46 arg: &str,
47 longs: I,
48 subcommands: &'z [App],
49 ) -> (String, Option<&'z str>)
50 where
51 T: AsRef<str> + 'z,
52 I: IntoIterator<Item = &'z T>,
53 {
54 match did_you_mean(arg, longs) {
55 Some(candidate) => {
56 let suffix = format!(
57 "\n\tDid you mean {}{}?",
58 Format::Good("--"),
59 Format::Good(candidate)
60 );
61 return (suffix, Some(candidate));
62 }
63 None => for subcommand in subcommands {
64 let opts = subcommand
65 .p
66 .flags
67 .iter()
68 .filter_map(|f| f.s.long)
69 .chain(subcommand.p.opts.iter().filter_map(|o| o.s.long));
70
71 if let Some(candidate) = did_you_mean(arg, opts) {
72 let suffix = format!(
73 "\n\tDid you mean to put '{}{}' after the subcommand '{}'?",
74 Format::Good("--"),
75 Format::Good(candidate),
76 Format::Good(subcommand.get_name())
77 );
78 return (suffix, Some(candidate));
79 }
80 },
81 }
82 (String::new(), None)
83 }
84
85 /// Returns a suffix that can be empty, or is the standard 'did you mean' phrase
86 pub fn did_you_mean_value_suffix<'z, T, I>(arg: &str, values: I) -> (String, Option<&'z str>)
87 where
88 T: AsRef<str> + 'z,
89 I: IntoIterator<Item = &'z T>,
90 {
91 match did_you_mean(arg, values) {
92 Some(candidate) => {
93 let suffix = format!("\n\tDid you mean '{}'?", Format::Good(candidate));
94 (suffix, Some(candidate))
95 }
96 None => (String::new(), None),
97 }
98 }
99
100 #[cfg(all(test, features = "suggestions"))]
101 mod test {
102 use super::*;
103
104 #[test]
105 fn possible_values_match() {
106 let p_vals = ["test", "possible", "values"];
107 assert_eq!(did_you_mean("tst", p_vals.iter()), Some("test"));
108 }
109
110 #[test]
111 fn possible_values_nomatch() {
112 let p_vals = ["test", "possible", "values"];
113 assert!(did_you_mean("hahaahahah", p_vals.iter()).is_none());
114 }
115
116 #[test]
117 fn suffix_long() {
118 let p_vals = ["test", "possible", "values"];
119 let suffix = "\n\tDid you mean \'--test\'?";
120 assert_eq!(
121 did_you_mean_flag_suffix("tst", p_vals.iter(), []),
122 (suffix, Some("test"))
123 );
124 }
125
126 #[test]
127 fn suffix_enum() {
128 let p_vals = ["test", "possible", "values"];
129 let suffix = "\n\tDid you mean \'test\'?";
130 assert_eq!(
131 did_you_mean_value_suffix("tst", p_vals.iter()),
132 (suffix, Some("test"))
133 );
134 }
135 }
136