lev_distance-0.1.1/.cargo_vcs_info.json0000644000000001360000000000100134730ustar { "git": { "sha1": "31c43eecf9670caa3d3ce43805e8e71e4044c1f8" }, "path_in_vcs": "" }lev_distance-0.1.1/.github/workflows/rust.yml000064400000000000000000000006340072674642500174330ustar 00000000000000name: Rust on: push: branches: [ main ] pull_request: branches: [ main ] env: CARGO_TERM_COLOR: always jobs: build: strategy: fail-fast: false matrix: os: [ ubuntu-latest, macos-latest ] runs-on: ${{ matrix.os }} steps: - uses: actions/checkout@v2 - name: Build run: cargo build --verbose - name: Run tests run: cargo test --verbose lev_distance-0.1.1/.gitignore000064400000000000000000000000230072674642500142760ustar 00000000000000/target Cargo.lock lev_distance-0.1.1/Cargo.toml0000644000000016140000000000100114730ustar # THIS FILE IS AUTOMATICALLY GENERATED BY CARGO # # When uploading crates to the registry Cargo will automatically # "normalize" Cargo.toml files for maximal compatibility # with all versions of Cargo and also rewrite `path` dependencies # to registry (e.g., crates.io) dependencies. # # If you are reading this file be aware that the original Cargo.toml # will likely look very different (and much more reasonable). # See Cargo.toml.orig for the original contents. [package] edition = "2021" name = "lev_distance" version = "0.1.1" authors = ["Ken Matsui <26405363+ken-matsui@users.noreply.github.com>"] description = "A copy of Levenshtein distance implementation from Rust Compiler" homepage = "https://github.com/ken-matsui/lev_distance#readme" documentation = "https://docs.rs/lev_distance" readme = "README.md" license = "MIT" repository = "https://github.com/ken-matsui/lev_distance/" resolver = "2" lev_distance-0.1.1/Cargo.toml.orig000064400000000000000000000006520072674642500152050ustar 00000000000000[package] name = "lev_distance" version = "0.1.1" edition = "2021" authors = ["Ken Matsui <26405363+ken-matsui@users.noreply.github.com>"] description = "A copy of Levenshtein distance implementation from Rust Compiler" license = "MIT" readme = "README.md" repository = "https://github.com/ken-matsui/lev_distance/" homepage = "https://github.com/ken-matsui/lev_distance#readme" documentation = "https://docs.rs/lev_distance" lev_distance-0.1.1/LICENSE000064400000000000000000000020530072674642500133200ustar 00000000000000MIT License Copyright (c) 2021 Ken Matsui Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. lev_distance-0.1.1/README.md000064400000000000000000000042260072674642500135760ustar 00000000000000# lev_distance A copy of Levenshtein distance implementation from [Rust Compiler](https://github.com/rust-lang/rust/blob/0fb1c371d4a14f9ce7a721d8aea683a6e6774f6c/compiler/rustc_span/src/lev_distance.rs). This package uses `String` instead of [`Symbol`](https://github.com/rust-lang/rust/blob/d6082292a6f3207cbdacd6633a5b9d1476bb6772/compiler/rustc_span/src/symbol.rs#L1625) of the Rust Compiler for general usage. ## Example ```rust use lev_distance::find_best_match_for_name; fn main() { let v = vec!["aaa", "bbb"]; let lookup = "aa"; if let Some(sugg) = match find_best_match_for_name(v.iter(), "aa", None) { Some(sugg) if sugg == lookup => None, sugg => sugg, } { println!("Did you mean `{}`?", sugg); } } ``` ```shell $ cargo run Did you mean `aaa`? ``` ## [LICENSE](https://github.com/ken-matsui/lev_distance/blob/main/src/lib.rs#L1-L26) This package is released under the MIT license from [Rust Compiler](https://github.com/rust-lang/rust/blob/0fb1c371d4a14f9ce7a721d8aea683a6e6774f6c/compiler/rustc_span/src/lev_distance.rs). ### Rust Compiler ``` Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. ``` The license for this package is placed [here](LICENSE). lev_distance-0.1.1/src/lib.rs000064400000000000000000000205450072674642500142240ustar 00000000000000//! This code is released under the MIT license //! # Rust Compiler //! //! Permission is hereby granted, free of charge, to any //! person obtaining a copy of this software and associated //! documentation files (the "Software"), to deal in the //! Software without restriction, including without //! limitation the rights to use, copy, modify, merge, //! publish, distribute, sublicense, and/or sell copies of //! the Software, and to permit persons to whom the Software //! is furnished to do so, subject to the following //! conditions: //! //! The above copyright notice and this permission notice //! shall be included in all copies or substantial portions //! of the Software. //! //! THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF //! ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED //! TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A //! PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT //! SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY //! CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION //! OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR //! IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER //! DEALINGS IN THE SOFTWARE. //! Levenshtein distances. //! //! The [Levenshtein distance] is a metric for measuring the difference between two strings. //! //! [Levenshtein distance]: https://en.wikipedia.org/wiki/Levenshtein_distance use std::cmp; /// Finds the Levenshtein distance between two strings. pub fn lev_distance(a: &str, b: &str) -> usize { // cases which don't require further computation if a.is_empty() { return b.chars().count(); } else if b.is_empty() { return a.chars().count(); } let mut dcol: Vec<_> = (0..=b.len()).collect(); let mut t_last = 0; for (i, sc) in a.chars().enumerate() { let mut current = i; dcol[0] = current + 1; for (j, tc) in b.chars().enumerate() { let next = dcol[j + 1]; if sc == tc { dcol[j + 1] = current; } else { dcol[j + 1] = cmp::min(current, next); dcol[j + 1] = cmp::min(dcol[j + 1], dcol[j]) + 1; } current = next; t_last = j; } } dcol[t_last + 1] } /// Finds the best match for a given word in the given iterator. /// /// As a loose rule to avoid the obviously incorrect suggestions, it takes /// an optional limit for the maximum allowable edit distance, which defaults /// to one-third of the given word. /// /// Besides Levenshtein, we use case insensitive comparison to improve accuracy /// on an edge case with a lower(upper)case letters mismatch. pub fn find_best_match_for_name( iter_names: impl Iterator + Clone, lookup: &str, dist: Option, ) -> Option where T: AsRef, { let max_dist = dist.unwrap_or_else(|| cmp::max(lookup.len(), 3) / 3); // Priority of matches: // 1. Exact case insensitive match // 2. Levenshtein distance match // 3. Sorted word match // 1. Exact case insensitive match for candidate in iter_names.clone() { if candidate.as_ref().to_uppercase() == lookup.to_uppercase() { return Some(candidate.as_ref().to_string()); } } // 2. Levenshtein distance match let levenshtein_match = iter_names .clone() .filter_map(|name| { let dist = lev_distance(lookup, name.as_ref()); if dist <= max_dist { Some((name, dist)) } else { None } }) // Here we are collecting the next structure: // (levenshtein_match, levenshtein_distance) .fold(None, |result, (candidate, dist)| match result { None => Some((candidate, dist)), Some((c, d)) => Some(if dist < d { (candidate, dist) } else { (c, d) }), }); // 3. Sorted word match if levenshtein_match.is_some() { levenshtein_match.map(|(candidate, _)| candidate.as_ref().to_string()) } else { find_match_by_sorted_words(iter_names, lookup) } } fn find_match_by_sorted_words( iter_names: impl Iterator, lookup: &str, ) -> Option where T: AsRef, { iter_names.fold(None, |result, candidate| { if sort_by_words(candidate.as_ref()) == sort_by_words(lookup) { Some(candidate.as_ref().to_string()) } else { result } }) } fn sort_by_words(name: &str) -> String { let mut split_words: Vec<&str> = name.split('_').collect(); // We are sorting primitive &strs and can use unstable sort here. split_words.sort_unstable(); split_words.join("_") } #[cfg(test)] mod tests { use super::*; #[test] fn test_lev_distance() { use std::char::{from_u32, MAX}; // Test bytelength agnosticity for c in (0..MAX as u32).filter_map(from_u32).map(|i| i.to_string()) { assert_eq!(lev_distance(&c[..], &c[..]), 0); } let a = "\nMäry häd ä little lämb\n\nLittle lämb\n"; let b = "\nMary häd ä little lämb\n\nLittle lämb\n"; let c = "Mary häd ä little lämb\n\nLittle lämb\n"; assert_eq!(lev_distance(a, b), 1); assert_eq!(lev_distance(b, a), 1); assert_eq!(lev_distance(a, c), 2); assert_eq!(lev_distance(c, a), 2); assert_eq!(lev_distance(b, c), 1); assert_eq!(lev_distance(c, b), 1); } #[test] fn test_find_best_match_for_name() { let input = vec!["aaab", "aaabc"]; assert_eq!( find_best_match_for_name(input.iter(), "aaaa", None), Some("aaab".to_string()) ); assert_eq!( find_best_match_for_name(input.iter(), "1111111111", None), None ); let input = vec!["AAAA"]; assert_eq!( find_best_match_for_name(input.iter(), "aaaa", None), Some("AAAA".to_string()) ); let input = vec!["AAAA"]; assert_eq!( find_best_match_for_name(input.iter(), "aaaa", Some(4)), Some("AAAA".to_string()) ); let input = vec!["a_longer_variable_name"]; assert_eq!( find_best_match_for_name(input.iter(), "a_variable_longer_name", None), Some("a_longer_variable_name".to_string()) ); } #[test] fn test_find_best_match_for_name_from_strings() { let input = vec!["aaab".to_string(), "aaabc".to_string()]; assert_eq!( find_best_match_for_name(input.iter(), "aaaa", None), Some("aaab".to_string()) ); assert_eq!( find_best_match_for_name(input.iter(), "1111111111", None), None ); let input = vec!["AAAA".to_string()]; assert_eq!( find_best_match_for_name(input.iter(), "aaaa", None), Some("AAAA".to_string()) ); let input = vec!["AAAA".to_string()]; assert_eq!( find_best_match_for_name(input.iter(), "aaaa", Some(4)), Some("AAAA".to_string()) ); let input = vec!["a_longer_variable_name".to_string()]; assert_eq!( find_best_match_for_name(input.iter(), "a_variable_longer_name", None), Some("a_longer_variable_name".to_string()) ); } #[test] fn test_find_best_match_for_name_from_hashset() { use std::collections::HashSet; let input: HashSet<&str> = vec!["aaab", "aaabc"].into_iter().collect(); assert_eq!( find_best_match_for_name(input.iter(), "aaaa", None), Some("aaab".to_string()) ); assert_eq!( find_best_match_for_name(input.iter(), "1111111111", None), None ); let input: HashSet<&str> = vec!["AAAA"].into_iter().collect(); assert_eq!( find_best_match_for_name(input.iter(), "aaaa", None), Some("AAAA".to_string()) ); let input: HashSet<&str> = vec!["AAAA"].into_iter().collect(); assert_eq!( find_best_match_for_name(input.iter(), "aaaa", Some(4)), Some("AAAA".to_string()) ); let input: HashSet<&str> = vec!["a_longer_variable_name"].into_iter().collect(); assert_eq!( find_best_match_for_name(input.iter(), "a_variable_longer_name", None), Some("a_longer_variable_name".to_string()) ); } }