clippy 0.0.63

A bunch of helpful lints to avoid common pitfalls in Rust
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#![feature(plugin)]
#![plugin(clippy)]
#![allow(unused, if_not_else)]

#![deny(map_entry)]

use std::collections::{BTreeMap, HashMap};
use std::hash::Hash;

fn foo() {}

fn insert_if_absent0<K: Eq + Hash, V>(m: &mut HashMap<K, V>, k: K, v: V) {
    if !m.contains_key(&k) { m.insert(k, v); }
    //~^ ERROR usage of `contains_key` followed by `insert` on `HashMap`
    //~| HELP Consider
    //~| SUGGESTION m.entry(k).or_insert(v)
}

fn insert_if_absent1<K: Eq + Hash, V>(m: &mut HashMap<K, V>, k: K, v: V) {
    if !m.contains_key(&k) { foo(); m.insert(k, v); }
    //~^ ERROR usage of `contains_key` followed by `insert` on `HashMap`
    //~| NOTE Consider using `m.entry(k)`
}

fn insert_if_absent2<K: Eq + Hash, V>(m: &mut HashMap<K, V>, k: K, v: V) {
    if !m.contains_key(&k) { m.insert(k, v) } else { None };
    //~^ ERROR usage of `contains_key` followed by `insert` on `HashMap`
    //~| NOTE Consider using `m.entry(k)`
}

fn insert_if_present2<K: Eq + Hash, V>(m: &mut HashMap<K, V>, k: K, v: V) {
    if m.contains_key(&k) { None } else { m.insert(k, v) };
    //~^ ERROR usage of `contains_key` followed by `insert` on `HashMap`
    //~| NOTE Consider using `m.entry(k)`
}

fn insert_if_absent3<K: Eq + Hash, V>(m: &mut HashMap<K, V>, k: K, v: V) {
    if !m.contains_key(&k) { foo(); m.insert(k, v) } else { None };
    //~^ ERROR usage of `contains_key` followed by `insert` on `HashMap`
    //~| NOTE Consider using `m.entry(k)`
}

fn insert_if_present3<K: Eq + Hash, V>(m: &mut HashMap<K, V>, k: K, v: V) {
    if m.contains_key(&k) { None } else { foo(); m.insert(k, v) };
    //~^ ERROR usage of `contains_key` followed by `insert` on `HashMap`
    //~| NOTE Consider using `m.entry(k)`
}

fn insert_in_btreemap<K: Ord, V>(m: &mut BTreeMap<K, V>, k: K, v: V) {
    if !m.contains_key(&k) { foo(); m.insert(k, v) } else { None };
    //~^ ERROR usage of `contains_key` followed by `insert` on `BTreeMap`
    //~| NOTE Consider using `m.entry(k)`
}

fn insert_other_if_absent<K: Eq + Hash, V>(m: &mut HashMap<K, V>, k: K, o: K, v: V) {
    if !m.contains_key(&k) { m.insert(o, v); }
}

fn main() {
}