error: usage of `contains_key` followed by `insert` on a `HashMap`
  --> entry.rs:13:5
   |
13 |     if !m.contains_key(&k) { m.insert(k, v); }
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using `m.entry(k).or_insert(v)`
   |
   = note: `-D map-entry` implied by `-D warnings`

error: usage of `contains_key` followed by `insert` on a `HashMap`
  --> entry.rs:17:5
   |
17 |     if !m.contains_key(&k) { foo(); m.insert(k, v); }
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using `m.entry(k)`
   |
   = note: `-D map-entry` implied by `-D warnings`

error: usage of `contains_key` followed by `insert` on a `HashMap`
  --> entry.rs:21:5
   |
21 |     if !m.contains_key(&k) { m.insert(k, v) } else { None };
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using `m.entry(k)`
   |
   = note: `-D map-entry` implied by `-D warnings`

error: usage of `contains_key` followed by `insert` on a `HashMap`
  --> entry.rs:25:5
   |
25 |     if m.contains_key(&k) { None } else { m.insert(k, v) };
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using `m.entry(k)`
   |
   = note: `-D map-entry` implied by `-D warnings`

error: usage of `contains_key` followed by `insert` on a `HashMap`
  --> entry.rs:29:5
   |
29 |     if !m.contains_key(&k) { foo(); m.insert(k, v) } else { None };
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using `m.entry(k)`
   |
   = note: `-D map-entry` implied by `-D warnings`

error: usage of `contains_key` followed by `insert` on a `HashMap`
  --> entry.rs:33:5
   |
33 |     if m.contains_key(&k) { None } else { foo(); m.insert(k, v) };
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using `m.entry(k)`
   |
   = note: `-D map-entry` implied by `-D warnings`

error: usage of `contains_key` followed by `insert` on a `BTreeMap`
  --> entry.rs:37:5
   |
37 |     if !m.contains_key(&k) { foo(); m.insert(k, v) } else { None };
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using `m.entry(k)`
   |
   = note: `-D map-entry` implied by `-D warnings`

error: aborting due to previous error(s)

error: Could not compile `clippy_tests`.

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