Assert causes panic with HashSet<String>

wordlist.rs

use serde_json::{self, from_str, Value};
use std::collections::{HashMap, HashSet};

use util::{bytes_to_hexstr, random_bytes};

const RAW_WORDS: &'static str = r#"{
\"00\": [\"aardvark\", \"adroitness\"], \"01\": [\"absurd\", \"adviser\"],
\"02\": [\"accrue\", \"aftermath\"], \"03\": [\"acme\", \"aggregate\"],
\"04\": [\"adrift\", \"alkali\"], \"05\": [\"adult\", \"almighty\"],
\"06\": [\"afflict\", \"amulet\"], \"07\": [\"ahead\", \"amusement\"],
\"08\": [\"aimless\", \"antenna\"], \"09\": [\"Algol\", \"applicant\"],
\"0A\": [\"allow\", \"Apollo\"], \"0B\": [\"alone\", \"armistice\"],
\"0C\": [\"ammo\", \"article\"], \"0D\": [\"ancient\", \"asteroid\"],
\"0E\": [\"apple\", \"Atlantic\"], \"0F\": [\"artist\", \"atmosphere\"],
\"10\": [\"assume\", \"autopsy\"], \"11\": [\"Athens\", \"Babylon\"],
\"12\": [\"atlas\", \"backwater\"], \"13\": [\"Aztec\", \"barbecue\"],
\"14\": [\"baboon\", \"belowground\"], \"15\": [\"backfield\", \"bifocals\"],
\"16\": [\"backward\", \"bodyguard\"], \"17\": [\"banjo\", \"bookseller\"],
\"18\": [\"beaming\", \"borderline\"], \"19\": [\"bedlamp\", \"bottomless\"],
\"1A\": [\"beehive\", \"Bradbury\"], \"1B\": [\"beeswax\", \"bravado\"],
\"1C\": [\"befriend\", \"Brazilian\"], \"1D\": [\"Belfast\", \"breakaway\"],
\"1E\": [\"berserk\", \"Burlington\"], \"1F\": [\"billiard\", \"businessman\"],
\"20\": [\"bison\", \"butterfat\"], \"21\": [\"blackjack\", \"Camelot\"],
\"22\": [\"blockade\", \"candidate\"], \"23\": [\"blowtorch\", \"cannonball\"],
\"24\": [\"bluebird\", \"Capricorn\"], \"25\": [\"bombast\", \"caravan\"],
\"26\": [\"bookshelf\", \"caretaker\"], \"27\": [\"brackish\", \"celebrate\"],
\"28\": [\"breadline\", \"cellulose\"], \"29\": [\"breakup\", \"certify\"],
\"2A\": [\"brickyard\", \"chambermaid\"], \"2B\": [\"briefcase\", \"Cherokee\"],
\"2C\": [\"Burbank\", \"Chicago\"], \"2D\": [\"button\", \"clergyman\"],
\"2E\": [\"buzzard\", \"coherence\"], \"2F\": [\"cement\", \"combustion\"],
\"30\": [\"chairlift\", \"commando\"], \"31\": [\"chatter\", \"company\"],
\"32\": [\"checkup\", \"component\"], \"33\": [\"chisel\", \"concurrent\"],
\"34\": [\"choking\", \"confidence\"], \"35\": [\"chopper\", \"conformist\"],
\"36\": [\"Christmas\", \"congregate\"], \"37\": [\"clamshell\", \"consensus\"],
\"38\": [\"classic\", \"consulting\"], \"39\": [\"classroom\", \"corporate\"],
\"3A\": [\"cleanup\", \"corrosion\"], \"3B\": [\"clockwork\", \"councilman\"],
\"3C\": [\"cobra\", \"crossover\"], \"3D\": [\"commence\", \"crucifix\"],
\"3E\": [\"concert\", \"cumbersome\"], \"3F\": [\"cowbell\", \"customer\"],
\"40\": [\"crackdown\", \"Dakota\"], \"41\": [\"cranky\", \"decadence\"],
\"42\": [\"crowfoot\", \"December\"], \"43\": [\"crucial\", \"decimal\"],
\"44\": [\"crumpled\", \"designing\"], \"45\": [\"crusade\", \"detector\"],
\"46\": [\"cubic\", \"detergent\"], \"47\": [\"dashboard\", \"determine\"],
\"48\": [\"deadbolt\", \"dictator\"], \"49\": [\"deckhand\", \"dinosaur\"],
\"4A\": [\"dogsled\", \"direction\"], \"4B\": [\"dragnet\", \"disable\"],
\"4C\": [\"drainage\", \"disbelief\"], \"4D\": [\"dreadful\", \"disruptive\"],
\"4E\": [\"drifter\", \"distortion\"], \"4F\": [\"dropper\", \"document\"],
\"50\": [\"drumbeat\", \"embezzle\"], \"51\": [\"drunken\", \"enchanting\"],
\"52\": [\"Dupont\", \"enrollment\"], \"53\": [\"dwelling\", \"enterprise\"],
\"54\": [\"eating\", \"equation\"], \"55\": [\"edict\", \"equipment\"],
\"56\": [\"egghead\", \"escapade\"], \"57\": [\"eightball\", \"Eskimo\"],
\"58\": [\"endorse\", \"everyday\"], \"59\": [\"endow\", \"examine\"],
\"5A\": [\"enlist\", \"existence\"], \"5B\": [\"erase\", \"exodus\"],
\"5C\": [\"escape\", \"fascinate\"], \"5D\": [\"exceed\", \"filament\"],
\"5E\": [\"eyeglass\", \"finicky\"], \"5F\": [\"eyetooth\", \"forever\"],
\"60\": [\"facial\", \"fortitude\"], \"61\": [\"fallout\", \"frequency\"],
\"62\": [\"flagpole\", \"gadgetry\"], \"63\": [\"flatfoot\", \"Galveston\"],
\"64\": [\"flytrap\", \"getaway\"], \"65\": [\"fracture\", \"glossary\"],
\"66\": [\"framework\", \"gossamer\"], \"67\": [\"freedom\", \"graduate\"],
\"68\": [\"frighten\", \"gravity\"], \"69\": [\"gazelle\", \"guitarist\"],
\"6A\": [\"Geiger\", \"hamburger\"], \"6B\": [\"glitter\", \"Hamilton\"],
\"6C\": [\"glucose\", \"handiwork\"], \"6D\": [\"goggles\", \"hazardous\"],
\"6E\": [\"goldfish\", \"headwaters\"], \"6F\": [\"gremlin\", \"hemisphere\"],
\"70\": [\"guidance\", \"hesitate\"], \"71\": [\"hamlet\", \"hideaway\"],
\"72\": [\"highchair\", \"holiness\"], \"73\": [\"hockey\", \"hurricane\"],
\"74\": [\"indoors\", \"hydraulic\"], \"75\": [\"indulge\", \"impartial\"],
\"76\": [\"inverse\", \"impetus\"], \"77\": [\"involve\", \"inception\"],
\"78\": [\"island\", \"indigo\"], \"79\": [\"jawbone\", \"inertia\"],
\"7A\": [\"keyboard\", \"infancy\"], \"7B\": [\"kickoff\", \"inferno\"],
\"7C\": [\"kiwi\", \"informant\"], \"7D\": [\"klaxon\", \"insincere\"],
\"7E\": [\"locale\", \"insurgent\"], \"7F\": [\"lockup\", \"integrate\"],
\"80\": [\"merit\", \"intention\"], \"81\": [\"minnow\", \"inventive\"],
\"82\": [\"miser\", \"Istanbul\"], \"83\": [\"Mohawk\", \"Jamaica\"],
\"84\": [\"mural\", \"Jupiter\"], \"85\": [\"music\", \"leprosy\"],
\"86\": [\"necklace\", \"letterhead\"], \"87\": [\"Neptune\", \"liberty\"],
\"88\": [\"newborn\", \"maritime\"], \"89\": [\"nightbird\", \"matchmaker\"],
\"8A\": [\"Oakland\", \"maverick\"], \"8B\": [\"obtuse\", \"Medusa\"],
\"8C\": [\"offload\", \"megaton\"], \"8D\": [\"optic\", \"microscope\"],
\"8E\": [\"orca\", \"microwave\"], \"8F\": [\"payday\", \"midsummer\"],
\"90\": [\"peachy\", \"millionaire\"], \"91\": [\"pheasant\", \"miracle\"],
\"92\": [\"physique\", \"misnomer\"], \"93\": [\"playhouse\", \"molasses\"],
\"94\": [\"Pluto\", \"molecule\"], \"95\": [\"preclude\", \"Montana\"],
\"96\": [\"prefer\", \"monument\"], \"97\": [\"preshrunk\", \"mosquito\"],
\"98\": [\"printer\", \"narrative\"], \"99\": [\"prowler\", \"nebula\"],
\"9A\": [\"pupil\", \"newsletter\"], \"9B\": [\"puppy\", \"Norwegian\"],
\"9C\": [\"python\", \"October\"], \"9D\": [\"quadrant\", \"Ohio\"],
\"9E\": [\"quiver\", \"onlooker\"], \"9F\": [\"quota\", \"opulent\"],
\"A0\": [\"ragtime\", \"Orlando\"], \"A1\": [\"ratchet\", \"outfielder\"],
\"A2\": [\"rebirth\", \"Pacific\"], \"A3\": [\"reform\", \"pandemic\"],
\"A4\": [\"regain\", \"Pandora\"], \"A5\": [\"reindeer\", \"paperweight\"],
\"A6\": [\"rematch\", \"paragon\"], \"A7\": [\"repay\", \"paragraph\"],
\"A8\": [\"retouch\", \"paramount\"], \"A9\": [\"revenge\", \"passenger\"],
\"AA\": [\"reward\", \"pedigree\"], \"AB\": [\"rhythm\", \"Pegasus\"],
\"AC\": [\"ribcage\", \"penetrate\"], \"AD\": [\"ringbolt\", \"perceptive\"],
\"AE\": [\"robust\", \"performance\"], \"AF\": [\"rocker\", \"pharmacy\"],
\"B0\": [\"ruffled\", \"phonetic\"], \"B1\": [\"sailboat\", \"photograph\"],
\"B2\": [\"sawdust\", \"pioneer\"], \"B3\": [\"scallion\", \"pocketful\"],
\"B4\": [\"scenic\", \"politeness\"], \"B5\": [\"scorecard\", \"positive\"],
\"B6\": [\"Scotland\", \"potato\"], \"B7\": [\"seabird\", \"processor\"],
\"B8\": [\"select\", \"provincial\"], \"B9\": [\"sentence\", \"proximate\"],
\"BA\": [\"shadow\", \"puberty\"], \"BB\": [\"shamrock\", \"publisher\"],
\"BC\": [\"showgirl\", \"pyramid\"], \"BD\": [\"skullcap\", \"quantity\"],
\"BE\": [\"skydive\", \"racketeer\"], \"BF\": [\"slingshot\", \"rebellion\"],
\"C0\": [\"slowdown\", \"recipe\"], \"C1\": [\"snapline\", \"recover\"],
\"C2\": [\"snapshot\", \"repellent\"], \"C3\": [\"snowcap\", \"replica\"],
\"C4\": [\"snowslide\", \"reproduce\"], \"C5\": [\"solo\", \"resistor\"],
\"C6\": [\"southward\", \"responsive\"], \"C7\": [\"soybean\", \"retraction\"],
\"C8\": [\"spaniel\", \"retrieval\"], \"C9\": [\"spearhead\", \"retrospect\"],
\"CA\": [\"spellbind\", \"revenue\"], \"CB\": [\"spheroid\", \"revival\"],
\"CC\": [\"spigot\", \"revolver\"], \"CD\": [\"spindle\", \"sandalwood\"],
\"CE\": [\"spyglass\", \"sardonic\"], \"CF\": [\"stagehand\", \"Saturday\"],
\"D0\": [\"stagnate\", \"savagery\"], \"D1\": [\"stairway\", \"scavenger\"],
\"D2\": [\"standard\", \"sensation\"], \"D3\": [\"stapler\", \"sociable\"],
\"D4\": [\"steamship\", \"souvenir\"], \"D5\": [\"sterling\", \"specialist\"],
\"D6\": [\"stockman\", \"speculate\"], \"D7\": [\"stopwatch\", \"stethoscope\"],
\"D8\": [\"stormy\", \"stupendous\"], \"D9\": [\"sugar\", \"supportive\"],
\"DA\": [\"surmount\", \"surrender\"], \"DB\": [\"suspense\", \"suspicious\"],
\"DC\": [\"sweatband\", \"sympathy\"], \"DD\": [\"swelter\", \"tambourine\"],
\"DE\": [\"tactics\", \"telephone\"], \"DF\": [\"talon\", \"therapist\"],
\"E0\": [\"tapeworm\", \"tobacco\"], \"E1\": [\"tempest\", \"tolerance\"],
\"E2\": [\"tiger\", \"tomorrow\"], \"E3\": [\"tissue\", \"torpedo\"],
\"E4\": [\"tonic\", \"tradition\"], \"E5\": [\"topmost\", \"travesty\"],
\"E6\": [\"tracker\", \"trombonist\"], \"E7\": [\"transit\", \"truncated\"],
\"E8\": [\"trauma\", \"typewriter\"], \"E9\": [\"treadmill\", \"ultimate\"],
\"EA\": [\"Trojan\", \"undaunted\"], \"EB\": [\"trouble\", \"underfoot\"],
\"EC\": [\"tumor\", \"unicorn\"], \"ED\": [\"tunnel\", \"unify\"],
\"EE\": [\"tycoon\", \"universe\"], \"EF\": [\"uncut\", \"unravel\"],
\"F0\": [\"unearth\", \"upcoming\"], \"F1\": [\"unwind\", \"vacancy\"],
\"F2\": [\"uproot\", \"vagabond\"], \"F3\": [\"upset\", \"vertigo\"],
\"F4\": [\"upshot\", \"Virginia\"], \"F5\": [\"vapor\", \"visitor\"],
\"F6\": [\"village\", \"vocalist\"], \"F7\": [\"virus\", \"voyager\"],
\"F8\": [\"Vulcan\", \"warranty\"], \"F9\": [\"waffle\", \"Waterloo\"],
\"FA\": [\"wallet\", \"whimsical\"], \"FB\": [\"watchword\", \"Wichita\"],
\"FC\": [\"wayside\", \"Wilmington\"], \"FD\": [\"willow\", \"Wyoming\"],
\"FE\": [\"woodlark\", \"yesteryear\"], \"FF\": [\"Zulu\", \"Yucatan\"]
}"#;

#[derive(Debug, PartialEq, Clone)]
pub struct PGPWordlist {
    _byte_even_words: HashMap<String, String>,
    _byte_odd_words: HashMap<String, String>,
}

impl PGPWordlist {
    pub fn new() -> Self {
        let raw_words: Value = serde_json::from_str(RAW_WORDS).unwrap();
        let map_obj = raw_words.as_object().unwrap();
        let even_words = map_obj
            .iter()
            .map(|item| {
                let (k, v): (&String, &Value) = item;
                let both_words: Vec<String> = v.as_array()
                    .unwrap()
                    .iter()
                    .map(|v| v.as_str().unwrap().to_string())
                    .collect();
                (k.to_string(), both_words[1].as_str().to_string())
            })
            .collect::<HashMap<String, String>>();
        let odd_words = map_obj
            .iter()
            .map(|item| {
                let (k, v): (&String, &Value) = item;
                let both_words: Vec<String> = v.as_array()
                    .unwrap()
                    .iter()
                    .map(|v| v.as_str().unwrap().to_string())
                    .collect();
                (k.to_string(), both_words[0].as_str().to_string())
            })
            .collect::<HashMap<String, String>>();

        PGPWordlist {
            _byte_even_words: even_words,
            _byte_odd_words: odd_words,
        }
    }

    pub fn get_completions(
        &self,
        prefix: &str,
        num_words: usize,
    ) -> HashSet<String> {
        let count_dashes = prefix.matches('-').count();
        let words;
        let mut completions = HashSet::new();

        if count_dashes % 2 == 0 {
            words = self._byte_odd_words
                .values()
                .map(String::to_string)
                .collect::<Vec<String>>();
        } else {
            words = self._byte_even_words
                .values()
                .map(String::to_string)
                .collect::<Vec<String>>();
        }

        let last_partial_word = prefix.split('-').last();
        let lp = if let Some(w) = last_partial_word {
            w.len()
        } else {
            0
        };

        for word in words {
            let mut suffix = prefix.to_string();
            if word.starts_with(last_partial_word.unwrap()) {
                if lp == 0 {
                    suffix.push_str(&word);
                } else {
                    let p = prefix.len() - lp;
                    suffix.insert_str(p as usize, &word);
                }

                if count_dashes + 1 < num_words {
                    suffix.push_str("-");
                }

                completions.insert(suffix);
            }
        }

        completions
    }

    pub fn choose_words(&self, length: u8) -> String {
        let mut rnd: [u8; 1] = [0; 1];
        let mut words: Vec<String> = Vec::new();
        for i in 0..length {
            random_bytes(&mut rnd);
            let key = bytes_to_hexstr(&rnd).to_uppercase();
            if i % 2 == 0 {
                let word = self._byte_odd_words[&key].as_str();
                words.push(word.to_string());
            } else {
                let word = self._byte_even_words[&key].as_str();
                words.push(word.to_string());
            }
        }

        words.join("-")
    }
}

#[cfg(test)]
mod test {
    use super::PGPWordlist;
    use std::collections::HashSet;

    #[test]
    fn test_completions() {
        let w = PGPWordlist::new();
        let c: HashSet<String> = w.get_completions("ar", 2);
        assert!(c.contains(&String::from("article-")));
    }
}