Auto merge of #6937 - Jarcho:map_entry_suggestion, r=giraffate

Improve `map_entry` suggestion

fixes: #5176
fixes: #4674
fixes: #4664
fixes: #1450

Still need to handle the value returned by `insert` correctly.

changelog: Improve `map_entry` suggestion. Will now suggest `or_insert`, `insert_with` or `match _.entry(_)` as appopriate.
changelog: Fix `map_entry` false positives where the entry api can't be used. e.g. when the map is used for multiple things.

tests/ui/entry.fixed

@@ -0,0 +1,155 @@
+// run-rustfix
+
+#![allow(unused, clippy::needless_pass_by_value, clippy::collapsible_if)]
+#![warn(clippy::map_entry)]
+#![feature(asm)]
+
+use std::collections::{BTreeMap, HashMap};
+use std::hash::Hash;
+
+macro_rules! m {
+    ($e:expr) => {{ $e }};
+}
+
+macro_rules! insert {
+    ($map:expr, $key:expr, $val:expr) => {
+        $map.insert($key, $val)
+    };
+}
+
+fn foo() {}
+
+fn hash_map<K: Eq + Hash + Copy, V: Copy>(m: &mut HashMap<K, V>, m2: &mut HashMap<K, V>, k: K, k2: K, v: V, v2: V) {
+    // or_insert(v)
+    m.entry(k).or_insert(v);
+
+    // semicolon on insert, use or_insert_with(..)
+    m.entry(k).or_insert_with(|| {
+        if true {
+            v
+        } else {
+            v2
+        }
+    });
+
+    // semicolon on if, use or_insert_with(..)
+    m.entry(k).or_insert_with(|| {
+        if true {
+            v
+        } else {
+            v2
+        }
+    });
+
+    // early return, use if let
+    if let std::collections::hash_map::Entry::Vacant(e) = m.entry(k) {
+        if true {
+            e.insert(v);
+        } else {
+            e.insert(v2);
+            return;
+        }
+    }
+
+    // use or_insert_with(..)
+    m.entry(k).or_insert_with(|| {
+        foo();
+        v
+    });
+
+    // semicolon on insert and match, use or_insert_with(..)
+    m.entry(k).or_insert_with(|| {
+        match 0 {
+            1 if true => {
+                v
+            },
+            _ => {
+                v2
+            },
+        }
+    });
+
+    // one branch doesn't insert, use if let
+    if let std::collections::hash_map::Entry::Vacant(e) = m.entry(k) {
+        match 0 {
+            0 => foo(),
+            _ => {
+                e.insert(v2);
+            },
+        };
+    }
+
+    // use or_insert_with
+    m.entry(k).or_insert_with(|| {
+        foo();
+        match 0 {
+            0 if false => {
+                v
+            },
+            1 => {
+                foo();
+                v
+            },
+            2 | 3 => {
+                for _ in 0..2 {
+                    foo();
+                }
+                if true {
+                    v
+                } else {
+                    v2
+                }
+            },
+            _ => {
+                v2
+            },
+        }
+    });
+
+    // ok, insert in loop
+    if !m.contains_key(&k) {
+        for _ in 0..2 {
+            m.insert(k, v);
+        }
+    }
+
+    // macro_expansion test, use or_insert(..)
+    m.entry(m!(k)).or_insert_with(|| m!(v));
+
+    // ok, map used before insertion
+    if !m.contains_key(&k) {
+        let _ = m.len();
+        m.insert(k, v);
+    }
+
+    // ok, inline asm
+    if !m.contains_key(&k) {
+        unsafe { asm!("nop") }
+        m.insert(k, v);
+    }
+
+    // ok, different keys.
+    if !m.contains_key(&k) {
+        m.insert(k2, v);
+    }
+
+    // ok, different maps
+    if !m.contains_key(&k) {
+        m2.insert(k, v);
+    }
+
+    // ok, insert in macro
+    if !m.contains_key(&k) {
+        insert!(m, k, v);
+    }
+}
+
+fn btree_map<K: Eq + Ord + Copy, V: Copy>(m: &mut BTreeMap<K, V>, k: K, v: V, v2: V) {
+    // insert then do something, use if let
+    if let std::collections::btree_map::Entry::Vacant(e) = m.entry(k) {
+        e.insert(v);
+        foo();
+    }
+}
+
+fn main() {}

tests/ui/entry.rs

@@ -0,0 +1,159 @@
+// run-rustfix
+
+#![allow(unused, clippy::needless_pass_by_value, clippy::collapsible_if)]
+#![warn(clippy::map_entry)]
+#![feature(asm)]
+
+use std::collections::{BTreeMap, HashMap};
+use std::hash::Hash;
+
+macro_rules! m {
+    ($e:expr) => {{ $e }};
+}
+
+macro_rules! insert {
+    ($map:expr, $key:expr, $val:expr) => {
+        $map.insert($key, $val)
+    };
+}
+
+fn foo() {}
+
+fn hash_map<K: Eq + Hash + Copy, V: Copy>(m: &mut HashMap<K, V>, m2: &mut HashMap<K, V>, k: K, k2: K, v: V, v2: V) {
+    // or_insert(v)
+    if !m.contains_key(&k) {
+        m.insert(k, v);
+    }
+
+    // semicolon on insert, use or_insert_with(..)
+    if !m.contains_key(&k) {
+        if true {
+            m.insert(k, v);
+        } else {
+            m.insert(k, v2);
+        }
+    }
+
+    // semicolon on if, use or_insert_with(..)
+    if !m.contains_key(&k) {
+        if true {
+            m.insert(k, v)
+        } else {
+            m.insert(k, v2)
+        };
+    }
+
+    // early return, use if let
+    if !m.contains_key(&k) {
+        if true {
+            m.insert(k, v);
+        } else {
+            m.insert(k, v2);
+            return;
+        }
+    }
+
+    // use or_insert_with(..)
+    if !m.contains_key(&k) {
+        foo();
+        m.insert(k, v);
+    }
+
+    // semicolon on insert and match, use or_insert_with(..)
+    if !m.contains_key(&k) {
+        match 0 {
+            1 if true => {
+                m.insert(k, v);
+            },
+            _ => {
+                m.insert(k, v2);
+            },
+        };
+    }
+
+    // one branch doesn't insert, use if let
+    if !m.contains_key(&k) {
+        match 0 {
+            0 => foo(),
+            _ => {
+                m.insert(k, v2);
+            },
+        };
+    }
+
+    // use or_insert_with
+    if !m.contains_key(&k) {
+        foo();
+        match 0 {
+            0 if false => {
+                m.insert(k, v);
+            },
+            1 => {
+                foo();
+                m.insert(k, v);
+            },
+            2 | 3 => {
+                for _ in 0..2 {
+                    foo();
+                }
+                if true {
+                    m.insert(k, v);
+                } else {
+                    m.insert(k, v2);
+                };
+            },
+            _ => {
+                m.insert(k, v2);
+            },
+        }
+    }
+
+    // ok, insert in loop
+    if !m.contains_key(&k) {
+        for _ in 0..2 {
+            m.insert(k, v);
+        }
+    }
+
+    // macro_expansion test, use or_insert(..)
+    if !m.contains_key(&m!(k)) {
+        m.insert(m!(k), m!(v));
+    }
+
+    // ok, map used before insertion
+    if !m.contains_key(&k) {
+        let _ = m.len();
+        m.insert(k, v);
+    }
+
+    // ok, inline asm
+    if !m.contains_key(&k) {
+        unsafe { asm!("nop") }
+        m.insert(k, v);
+    }
+
+    // ok, different keys.
+    if !m.contains_key(&k) {
+        m.insert(k2, v);
+    }
+
+    // ok, different maps
+    if !m.contains_key(&k) {
+        m2.insert(k, v);
+    }
+
+    // ok, insert in macro
+    if !m.contains_key(&k) {
+        insert!(m, k, v);
+    }
+}
+
+fn btree_map<K: Eq + Ord + Copy, V: Copy>(m: &mut BTreeMap<K, V>, k: K, v: V, v2: V) {
+    // insert then do something, use if let
+    if !m.contains_key(&k) {
+        m.insert(k, v);
+        foo();
+    }
+}
+
+fn main() {}

tests/ui/entry.stderr

@@ -0,0 +1,186 @@
+error: usage of `contains_key` followed by `insert` on a `HashMap`
+  --> $DIR/entry.rs:24:5
+   |
+LL | /     if !m.contains_key(&k) {
+LL | |         m.insert(k, v);
+LL | |     }
+   | |_____^ help: try this: `m.entry(k).or_insert(v);`
+   |
+   = note: `-D clippy::map-entry` implied by `-D warnings`
+
+error: usage of `contains_key` followed by `insert` on a `HashMap`
+  --> $DIR/entry.rs:29:5
+   |
+LL | /     if !m.contains_key(&k) {
+LL | |         if true {
+LL | |             m.insert(k, v);
+LL | |         } else {
+LL | |             m.insert(k, v2);
+LL | |         }
+LL | |     }
+   | |_____^
+   |
+help: try this
+   |
+LL |     m.entry(k).or_insert_with(|| {
+LL |         if true {
+LL |             v
+LL |         } else {
+LL |             v2
+LL |         }
+ ...
+
+error: usage of `contains_key` followed by `insert` on a `HashMap`
+  --> $DIR/entry.rs:38:5
+   |
+LL | /     if !m.contains_key(&k) {
+LL | |         if true {
+LL | |             m.insert(k, v)
+LL | |         } else {
+LL | |             m.insert(k, v2)
+LL | |         };
+LL | |     }
+   | |_____^
+   |
+help: try this
+   |
+LL |     m.entry(k).or_insert_with(|| {
+LL |         if true {
+LL |             v
+LL |         } else {
+LL |             v2
+LL |         }
+ ...
+
+error: usage of `contains_key` followed by `insert` on a `HashMap`
+  --> $DIR/entry.rs:47:5
+   |
+LL | /     if !m.contains_key(&k) {
+LL | |         if true {
+LL | |             m.insert(k, v);
+LL | |         } else {
+...  |
+LL | |         }
+LL | |     }
+   | |_____^
+   |
+help: try this
+   |
+LL |     if let std::collections::hash_map::Entry::Vacant(e) = m.entry(k) {
+LL |         if true {
+LL |             e.insert(v);
+LL |         } else {
+LL |             e.insert(v2);
+LL |             return;
+ ...
+
+error: usage of `contains_key` followed by `insert` on a `HashMap`
+  --> $DIR/entry.rs:57:5
+   |
+LL | /     if !m.contains_key(&k) {
+LL | |         foo();
+LL | |         m.insert(k, v);
+LL | |     }
+   | |_____^
+   |
+help: try this
+   |
+LL |     m.entry(k).or_insert_with(|| {
+LL |         foo();
+LL |         v
+LL |     });
+   |
+
+error: usage of `contains_key` followed by `insert` on a `HashMap`
+  --> $DIR/entry.rs:63:5
+   |
+LL | /     if !m.contains_key(&k) {
+LL | |         match 0 {
+LL | |             1 if true => {
+LL | |                 m.insert(k, v);
+...  |
+LL | |         };
+LL | |     }
+   | |_____^
+   |
+help: try this
+   |
+LL |     m.entry(k).or_insert_with(|| {
+LL |         match 0 {
+LL |             1 if true => {
+LL |                 v
+LL |             },
+LL |             _ => {
+ ...
+
+error: usage of `contains_key` followed by `insert` on a `HashMap`
+  --> $DIR/entry.rs:75:5
+   |
+LL | /     if !m.contains_key(&k) {
+LL | |         match 0 {
+LL | |             0 => foo(),
+LL | |             _ => {
+...  |
+LL | |         };
+LL | |     }
+   | |_____^
+   |
+help: try this
+   |
+LL |     if let std::collections::hash_map::Entry::Vacant(e) = m.entry(k) {
+LL |         match 0 {
+LL |             0 => foo(),
+LL |             _ => {
+LL |                 e.insert(v2);
+LL |             },
+ ...
+
+error: usage of `contains_key` followed by `insert` on a `HashMap`
+  --> $DIR/entry.rs:85:5
+   |
+LL | /     if !m.contains_key(&k) {
+LL | |         foo();
+LL | |         match 0 {
+LL | |             0 if false => {
+...  |
+LL | |         }
+LL | |     }
+   | |_____^
+   |
+help: try this
+   |
+LL |     m.entry(k).or_insert_with(|| {
+LL |         foo();
+LL |         match 0 {
+LL |             0 if false => {
+LL |                 v
+LL |             },
+ ...
+
+error: usage of `contains_key` followed by `insert` on a `HashMap`
+  --> $DIR/entry.rs:119:5
+   |
+LL | /     if !m.contains_key(&m!(k)) {
+LL | |         m.insert(m!(k), m!(v));
+LL | |     }
+   | |_____^ help: try this: `m.entry(m!(k)).or_insert_with(|| m!(v));`
+
+error: usage of `contains_key` followed by `insert` on a `BTreeMap`
+  --> $DIR/entry.rs:153:5
+   |
+LL | /     if !m.contains_key(&k) {
+LL | |         m.insert(k, v);
+LL | |         foo();
+LL | |     }
+   | |_____^
+   |
+help: try this
+   |
+LL |     if let std::collections::btree_map::Entry::Vacant(e) = m.entry(k) {
+LL |         e.insert(v);
+LL |         foo();
+LL |     }
+   |
+
+error: aborting due to 10 previous errors
+

tests/ui/entry_fixable.fixed

@@ -1,15 +0,0 @@
-// run-rustfix
-
-#![allow(unused, clippy::needless_pass_by_value)]
-#![warn(clippy::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) {
-    m.entry(k).or_insert(v);
-}
-
-fn main() {}

tests/ui/entry_fixable.rs

@@ -1,17 +0,0 @@
-// run-rustfix
-
-#![allow(unused, clippy::needless_pass_by_value)]
-#![warn(clippy::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);
-    }
-}
-
-fn main() {}

tests/ui/entry_fixable.stderr

@@ -1,12 +0,0 @@
-error: usage of `contains_key` followed by `insert` on a `HashMap`
-  --> $DIR/entry_fixable.rs:12:5
-   |
-LL | /     if !m.contains_key(&k) {
-LL | |         m.insert(k, v);
-LL | |     }
-   | |_____^ help: consider using: `m.entry(k).or_insert(v);`
-   |
-   = note: `-D clippy::map-entry` implied by `-D warnings`
-
-error: aborting due to previous error
-

tests/ui/entry_unfixable.rs

@@ -1,73 +0,0 @@
-#![allow(unused, clippy::needless_pass_by_value)]
-#![warn(clippy::map_entry)]
-
-use std::collections::{BTreeMap, HashMap};
-use std::hash::Hash;
-
-fn foo() {}
-
-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
-    };
-}
-
-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)
-    };
-}
-
-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
-    };
-}
-
-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)
-    };
-}
-
-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
-    };
-}
-
-// should not trigger
-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);
-    }
-}
-
-// should not trigger, because the one uses different HashMap from another one
-fn insert_from_different_map<K: Eq + Hash, V>(m: HashMap<K, V>, n: &mut HashMap<K, V>, k: K, v: V) {
-    if !m.contains_key(&k) {
-        n.insert(k, v);
-    }
-}
-
-// should not trigger, because the one uses different HashMap from another one
-fn insert_from_different_map2<K: Eq + Hash, V>(m: &mut HashMap<K, V>, n: &mut HashMap<K, V>, k: K, v: V) {
-    if !m.contains_key(&k) {
-        n.insert(k, v);
-    }
-}
-
-fn main() {}

tests/ui/entry_unfixable.stderr

@@ -1,57 +0,0 @@
-error: usage of `contains_key` followed by `insert` on a `HashMap`
-  --> $DIR/entry_unfixable.rs:10:5
-   |
-LL | /     if !m.contains_key(&k) {
-LL | |         m.insert(k, v)
-LL | |     } else {
-LL | |         None
-LL | |     };
-   | |_____^ consider using `m.entry(k)`
-   |
-   = note: `-D clippy::map-entry` implied by `-D warnings`
-
-error: usage of `contains_key` followed by `insert` on a `HashMap`
-  --> $DIR/entry_unfixable.rs:18:5
-   |
-LL | /     if m.contains_key(&k) {
-LL | |         None
-LL | |     } else {
-LL | |         m.insert(k, v)
-LL | |     };
-   | |_____^ consider using `m.entry(k)`
-
-error: usage of `contains_key` followed by `insert` on a `HashMap`
-  --> $DIR/entry_unfixable.rs:26:5
-   |
-LL | /     if !m.contains_key(&k) {
-LL | |         foo();
-LL | |         m.insert(k, v)
-LL | |     } else {
-LL | |         None
-LL | |     };
-   | |_____^ consider using `m.entry(k)`
-
-error: usage of `contains_key` followed by `insert` on a `HashMap`
-  --> $DIR/entry_unfixable.rs:35:5
-   |
-LL | /     if m.contains_key(&k) {
-LL | |         None
-LL | |     } else {
-LL | |         foo();
-LL | |         m.insert(k, v)
-LL | |     };
-   | |_____^ consider using `m.entry(k)`
-
-error: usage of `contains_key` followed by `insert` on a `BTreeMap`
-  --> $DIR/entry_unfixable.rs:44:5
-   |
-LL | /     if !m.contains_key(&k) {
-LL | |         foo();
-LL | |         m.insert(k, v)
-LL | |     } else {
-LL | |         None
-LL | |     };
-   | |_____^ consider using `m.entry(k)`
-
-error: aborting due to 5 previous errors
-

tests/ui/entry_with_else.fixed

@@ -0,0 +1,73 @@
+// run-rustfix
+
+#![allow(unused, clippy::needless_pass_by_value, clippy::collapsible_if)]
+#![warn(clippy::map_entry)]
+
+use std::collections::{BTreeMap, HashMap};
+use std::hash::Hash;
+
+macro_rules! m {
+    ($e:expr) => {{ $e }};
+}
+
+fn foo() {}
+
+fn insert_if_absent0<K: Eq + Hash + Copy, V: Copy>(m: &mut HashMap<K, V>, k: K, v: V, v2: V) {
+    match m.entry(k) {
+        std::collections::hash_map::Entry::Vacant(e) => {
+            e.insert(v);
+        }
+        std::collections::hash_map::Entry::Occupied(mut e) => {
+            e.insert(v2);
+        }
+    }
+
+    match m.entry(k) {
+        std::collections::hash_map::Entry::Occupied(mut e) => {
+            e.insert(v);
+        }
+        std::collections::hash_map::Entry::Vacant(e) => {
+            e.insert(v2);
+        }
+    }
+
+    if let std::collections::hash_map::Entry::Vacant(e) = m.entry(k) {
+        e.insert(v);
+    } else {
+        foo();
+    }
+
+    if let std::collections::hash_map::Entry::Occupied(mut e) = m.entry(k) {
+        e.insert(v);
+    } else {
+        foo();
+    }
+
+    match m.entry(k) {
+        std::collections::hash_map::Entry::Vacant(e) => {
+            e.insert(v);
+        }
+        std::collections::hash_map::Entry::Occupied(mut e) => {
+            e.insert(v2);
+        }
+    }
+
+    match m.entry(k) {
+        std::collections::hash_map::Entry::Occupied(mut e) => {
+            if true { Some(e.insert(v)) } else { Some(e.insert(v2)) }
+        }
+        std::collections::hash_map::Entry::Vacant(e) => {
+            e.insert(v);
+            None
+        }
+    };
+
+    if let std::collections::hash_map::Entry::Occupied(mut e) = m.entry(k) {
+        foo();
+        Some(e.insert(v))
+    } else {
+        None
+    };
+}
+
+fn main() {}

tests/ui/entry_with_else.rs

@@ -0,0 +1,60 @@
+// run-rustfix
+
+#![allow(unused, clippy::needless_pass_by_value, clippy::collapsible_if)]
+#![warn(clippy::map_entry)]
+
+use std::collections::{BTreeMap, HashMap};
+use std::hash::Hash;
+
+macro_rules! m {
+    ($e:expr) => {{ $e }};
+}
+
+fn foo() {}
+
+fn insert_if_absent0<K: Eq + Hash + Copy, V: Copy>(m: &mut HashMap<K, V>, k: K, v: V, v2: V) {
+    if !m.contains_key(&k) {
+        m.insert(k, v);
+    } else {
+        m.insert(k, v2);
+    }
+
+    if m.contains_key(&k) {
+        m.insert(k, v);
+    } else {
+        m.insert(k, v2);
+    }
+
+    if !m.contains_key(&k) {
+        m.insert(k, v);
+    } else {
+        foo();
+    }
+
+    if !m.contains_key(&k) {
+        foo();
+    } else {
+        m.insert(k, v);
+    }
+
+    if !m.contains_key(&k) {
+        m.insert(k, v);
+    } else {
+        m.insert(k, v2);
+    }
+
+    if m.contains_key(&k) {
+        if true { m.insert(k, v) } else { m.insert(k, v2) }
+    } else {
+        m.insert(k, v)
+    };
+
+    if m.contains_key(&k) {
+        foo();
+        m.insert(k, v)
+    } else {
+        None
+    };
+}
+
+fn main() {}

tests/ui/entry_with_else.stderr

@@ -0,0 +1,142 @@
+error: usage of `contains_key` followed by `insert` on a `HashMap`
+  --> $DIR/entry_with_else.rs:16:5
+   |
+LL | /     if !m.contains_key(&k) {
+LL | |         m.insert(k, v);
+LL | |     } else {
+LL | |         m.insert(k, v2);
+LL | |     }
+   | |_____^
+   |
+   = note: `-D clippy::map-entry` implied by `-D warnings`
+help: try this
+   |
+LL |     match m.entry(k) {
+LL |         std::collections::hash_map::Entry::Vacant(e) => {
+LL |             e.insert(v);
+LL |         }
+LL |         std::collections::hash_map::Entry::Occupied(mut e) => {
+LL |             e.insert(v2);
+ ...
+
+error: usage of `contains_key` followed by `insert` on a `HashMap`
+  --> $DIR/entry_with_else.rs:22:5
+   |
+LL | /     if m.contains_key(&k) {
+LL | |         m.insert(k, v);
+LL | |     } else {
+LL | |         m.insert(k, v2);
+LL | |     }
+   | |_____^
+   |
+help: try this
+   |
+LL |     match m.entry(k) {
+LL |         std::collections::hash_map::Entry::Occupied(mut e) => {
+LL |             e.insert(v);
+LL |         }
+LL |         std::collections::hash_map::Entry::Vacant(e) => {
+LL |             e.insert(v2);
+ ...
+
+error: usage of `contains_key` followed by `insert` on a `HashMap`
+  --> $DIR/entry_with_else.rs:28:5
+   |
+LL | /     if !m.contains_key(&k) {
+LL | |         m.insert(k, v);
+LL | |     } else {
+LL | |         foo();
+LL | |     }
+   | |_____^
+   |
+help: try this
+   |
+LL |     if let std::collections::hash_map::Entry::Vacant(e) = m.entry(k) {
+LL |         e.insert(v);
+LL |     } else {
+LL |         foo();
+LL |     }
+   |
+
+error: usage of `contains_key` followed by `insert` on a `HashMap`
+  --> $DIR/entry_with_else.rs:34:5
+   |
+LL | /     if !m.contains_key(&k) {
+LL | |         foo();
+LL | |     } else {
+LL | |         m.insert(k, v);
+LL | |     }
+   | |_____^
+   |
+help: try this
+   |
+LL |     if let std::collections::hash_map::Entry::Occupied(mut e) = m.entry(k) {
+LL |         e.insert(v);
+LL |     } else {
+LL |         foo();
+LL |     }
+   |
+
+error: usage of `contains_key` followed by `insert` on a `HashMap`
+  --> $DIR/entry_with_else.rs:40:5
+   |
+LL | /     if !m.contains_key(&k) {
+LL | |         m.insert(k, v);
+LL | |     } else {
+LL | |         m.insert(k, v2);
+LL | |     }
+   | |_____^
+   |
+help: try this
+   |
+LL |     match m.entry(k) {
+LL |         std::collections::hash_map::Entry::Vacant(e) => {
+LL |             e.insert(v);
+LL |         }
+LL |         std::collections::hash_map::Entry::Occupied(mut e) => {
+LL |             e.insert(v2);
+ ...
+
+error: usage of `contains_key` followed by `insert` on a `HashMap`
+  --> $DIR/entry_with_else.rs:46:5
+   |
+LL | /     if m.contains_key(&k) {
+LL | |         if true { m.insert(k, v) } else { m.insert(k, v2) }
+LL | |     } else {
+LL | |         m.insert(k, v)
+LL | |     };
+   | |_____^
+   |
+help: try this
+   |
+LL |     match m.entry(k) {
+LL |         std::collections::hash_map::Entry::Occupied(mut e) => {
+LL |             if true { Some(e.insert(v)) } else { Some(e.insert(v2)) }
+LL |         }
+LL |         std::collections::hash_map::Entry::Vacant(e) => {
+LL |             e.insert(v);
+ ...
+
+error: usage of `contains_key` followed by `insert` on a `HashMap`
+  --> $DIR/entry_with_else.rs:52:5
+   |
+LL | /     if m.contains_key(&k) {
+LL | |         foo();
+LL | |         m.insert(k, v)
+LL | |     } else {
+LL | |         None
+LL | |     };
+   | |_____^
+   |
+help: try this
+   |
+LL |     if let std::collections::hash_map::Entry::Occupied(mut e) = m.entry(k) {
+LL |         foo();
+LL |         Some(e.insert(v))
+LL |     } else {
+LL |         None
+LL |     };
+   |
+
+error: aborting due to 7 previous errors
+

tests/ui/string_lit_as_bytes.fixed

@@ -22,7 +22,7 @@ fn str_lit_as_bytes() {
 
     let current_version = env!("CARGO_PKG_VERSION").as_bytes();
 
-    let includestr = include_bytes!("entry_unfixable.rs");
+    let includestr = include_bytes!("string_lit_as_bytes.rs");
 
     let _ = b"string with newline\t\n";
 }

tests/ui/string_lit_as_bytes.rs

@@ -22,7 +22,7 @@ fn str_lit_as_bytes() {
 
     let current_version = env!("CARGO_PKG_VERSION").as_bytes();
 
-    let includestr = include_str!("entry_unfixable.rs").as_bytes();
+    let includestr = include_str!("string_lit_as_bytes.rs").as_bytes();
 
     let _ = "string with newline\t\n".as_bytes();
 }

tests/ui/string_lit_as_bytes.stderr

@@ -27,8 +27,8 @@ LL |     let bs = "lit to owned".to_owned().into_bytes();
 error: calling `as_bytes()` on `include_str!(..)`
   --> $DIR/string_lit_as_bytes.rs:25:22
    |
-LL |     let includestr = include_str!("entry_unfixable.rs").as_bytes();
-   |                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using `include_bytes!(..)` instead: `include_bytes!("entry_unfixable.rs")`
+LL |     let includestr = include_str!("string_lit_as_bytes.rs").as_bytes();
+   |                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using `include_bytes!(..)` instead: `include_bytes!("string_lit_as_bytes.rs")`
 
 error: calling `as_bytes()` on a string literal
   --> $DIR/string_lit_as_bytes.rs:27:13