Type parameter change and type change are now in a multispan suggestion

sinkuu · sinkuu · commit eea30777ddef · 2017-10-17T21:40:46.000+09:00
diff --git a/clippy_lints/src/types.rs b/clippy_lints/src/types.rs
@@ -1453,8 +1453,8 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for InvalidUpcastComparisons {
     }
 }
 
-/// **What it does:** Checks for public `impl` or `fn` missing generalization over
-/// different hashers and implicitly defaulting to the default hashing
+/// **What it does:** Checks for public `impl` or `fn` missing generalization
+/// over different hashers and implicitly defaulting to the default hashing
 /// algorithm (SipHash).
 ///
 /// **Why is this bad?** `HashMap` or `HashSet` with custom hashers cannot be
@@ -1505,26 +1505,29 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for ImplicitHasher {
                 &generics_snip[1..generics_snip.len() - 1]
             };
 
-            db.span_suggestion(
-                generics_suggestion_span,
-                "consider adding a type parameter",
-                format!(
-                    "<{}{}S: ::std::hash::BuildHasher{}>",
-                    generics_snip,
-                    if generics_snip.is_empty() { "" } else { ", " },
-                    if vis.suggestions.is_empty() {
-                        ""
-                    } else {
-                        // request users to add `Default` bound so that generic constructors can be used
-                        " + Default"
-                    },
-                ),
-            );
-
-            db.span_suggestion(
-                target.span(),
-                "...and change the type to",
-                format!("{}<{}, S>", target.type_name(), target.type_arguments(),),
+            multispan_sugg(
+                db,
+                "consider adding a type parameter".to_string(),
+                vec![
+                    (
+                        generics_suggestion_span,
+                        format!(
+                            "<{}{}S: ::std::hash::BuildHasher{}>",
+                            generics_snip,
+                            if generics_snip.is_empty() { "" } else { ", " },
+                            if vis.suggestions.is_empty() {
+                                ""
+                            } else {
+                                // request users to add `Default` bound so that generic constructors can be used
+                                " + Default"
+                            },
+                        ),
+                    ),
+                    (
+                        target.span(),
+                        format!("{}<{}, S>", target.type_name(), target.type_arguments(),),
+                    ),
+                ],
             );
 
             if !vis.suggestions.is_empty() {
diff --git a/tests/ui/implicit_hasher.stderr b/tests/ui/implicit_hasher.stderr
@@ -7,12 +7,8 @@ error: impl for `HashMap` should be generarized over different hashers
    = note: `-D implicit-hasher` implied by `-D warnings`
 help: consider adding a type parameter
    |
-11 | impl<K: Hash + Eq, V, S: ::std::hash::BuildHasher + Default> Foo<i8> for HashMap<K, V> {
+11 | impl<K: Hash + Eq, V, S: ::std::hash::BuildHasher + Default> Foo<i8> for HashMap<K, V, S> {
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-help: ...and change the type to
-   |
-11 | impl<K: Hash + Eq, V> Foo<i8> for HashMap<K, V, S> {
-   |                                   ^^^^^^^^^^^^^^^^
 help: ...and use generic constructor
    |
 17 |         (HashMap::default(), HashMap::with_capacity_and_hasher(10, Default::default()))
@@ -26,12 +22,8 @@ error: impl for `HashMap` should be generarized over different hashers
    |
 help: consider adding a type parameter
    |
-20 | impl<K: Hash + Eq, V, S: ::std::hash::BuildHasher + Default> Foo<i8> for (HashMap<K, V>,) {
+20 | impl<K: Hash + Eq, V, S: ::std::hash::BuildHasher + Default> Foo<i8> for (HashMap<K, V, S>,) {
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-help: ...and change the type to
-   |
-20 | impl<K: Hash + Eq, V> Foo<i8> for (HashMap<K, V, S>,) {
-   |                                    ^^^^^^^^^^^^^^^^
 help: ...and use generic constructor
    |
 22 |         ((HashMap::default(),), (HashMap::with_capacity_and_hasher(10, Default::default()),))
@@ -45,12 +37,8 @@ error: impl for `HashMap` should be generarized over different hashers
    |
 help: consider adding a type parameter
    |
-25 | impl<S: ::std::hash::BuildHasher + Default> Foo<i16> for HashMap<String, String> {
+25 | impl<S: ::std::hash::BuildHasher + Default> Foo<i16> for HashMap<String, String, S> {
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-help: ...and change the type to
-   |
-25 | impl Foo<i16> for HashMap<String, String, S> {
-   |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^
 help: ...and use generic constructor
    |
 27 |         (HashMap::default(), HashMap::with_capacity_and_hasher(10, Default::default()))
@@ -64,12 +52,8 @@ error: impl for `HashSet` should be generarized over different hashers
    |
 help: consider adding a type parameter
    |
-43 | impl<T: Hash + Eq, S: ::std::hash::BuildHasher + Default> Foo<i8> for HashSet<T> {
+43 | impl<T: Hash + Eq, S: ::std::hash::BuildHasher + Default> Foo<i8> for HashSet<T, S> {
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-help: ...and change the type to
-   |
-43 | impl<T: Hash + Eq> Foo<i8> for HashSet<T, S> {
-   |                                ^^^^^^^^^^^^^
 help: ...and use generic constructor
    |
 45 |         (HashSet::default(), HashSet::with_capacity_and_hasher(10, Default::default()))
@@ -83,12 +67,8 @@ error: impl for `HashSet` should be generarized over different hashers
    |
 help: consider adding a type parameter
    |
-48 | impl<S: ::std::hash::BuildHasher + Default> Foo<i16> for HashSet<String> {
+48 | impl<S: ::std::hash::BuildHasher + Default> Foo<i16> for HashSet<String, S> {
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-help: ...and change the type to
-   |
-48 | impl Foo<i16> for HashSet<String, S> {
-   |                   ^^^^^^^^^^^^^^^^^^
 help: ...and use generic constructor
    |
 50 |         (HashSet::default(), HashSet::with_capacity_and_hasher(10, Default::default()))
@@ -102,12 +82,8 @@ error: parameter of type `HashMap` should be generarized over different hashers
    |
 help: consider adding a type parameter
    |
-65 | pub fn foo<S: ::std::hash::BuildHasher>(_map: &mut HashMap<i32, i32>, _set: &mut HashSet<i32>) {
+65 | pub fn foo<S: ::std::hash::BuildHasher>(_map: &mut HashMap<i32, i32, S>, _set: &mut HashSet<i32>) {
    |           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-help: ...and change the type to
-   |
-65 | pub fn foo(_map: &mut HashMap<i32, i32, S>, _set: &mut HashSet<i32>) {
-   |                       ^^^^^^^^^^^^^^^^^^^^
 
 error: parameter of type `HashSet` should be generarized over different hashers
   --> $DIR/implicit_hasher.rs:65:53
@@ -117,12 +93,8 @@ error: parameter of type `HashSet` should be generarized over different hashers
    |
 help: consider adding a type parameter
    |
-65 | pub fn foo<S: ::std::hash::BuildHasher>(_map: &mut HashMap<i32, i32>, _set: &mut HashSet<i32>) {
+65 | pub fn foo<S: ::std::hash::BuildHasher>(_map: &mut HashMap<i32, i32>, _set: &mut HashSet<i32, S>) {
    |           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-help: ...and change the type to
-   |
-65 | pub fn foo(_map: &mut HashMap<i32, i32>, _set: &mut HashSet<i32, S>) {
-   |                                                     ^^^^^^^^^^^^^^^
 
 error: impl for `HashMap` should be generarized over different hashers
   --> $DIR/implicit_hasher.rs:70:43
@@ -135,12 +107,8 @@ error: impl for `HashMap` should be generarized over different hashers
    |
 help: consider adding a type parameter
    |
-70 |         impl<K: Hash + Eq, V, S: ::std::hash::BuildHasher + Default> Foo<u8> for HashMap<K, V> {
+70 |         impl<K: Hash + Eq, V, S: ::std::hash::BuildHasher + Default> Foo<u8> for HashMap<K, V, S> {
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-help: ...and change the type to
-   |
-70 |         impl<K: Hash + Eq, V> Foo<u8> for HashMap<K, V, S> {
-   |                                           ^^^^^^^^^^^^^^^^
 help: ...and use generic constructor
    |
 72 |                 (HashMap::default(), HashMap::with_capacity_and_hasher(10, Default::default()))
@@ -157,12 +125,8 @@ error: parameter of type `HashMap` should be generarized over different hashers
    |
 help: consider adding a type parameter
    |
-78 |         pub fn $name<S: ::std::hash::BuildHasher>(_map: &mut HashMap<i32, i32>, _set: &mut HashSet<i32>) {
+78 |         pub fn $name<S: ::std::hash::BuildHasher>(_map: &mut HashMap<i32, i32, S>, _set: &mut HashSet<i32>) {
    |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-help: ...and change the type to
-   |
-78 |         pub fn $name(_map: &mut HashMap<i32, i32, S>, _set: &mut HashSet<i32>) {
-   |                                 ^^^^^^^^^^^^^^^^^^^^
 
 error: parameter of type `HashSet` should be generarized over different hashers
   --> $DIR/implicit_hasher.rs:78:63
@@ -175,10 +139,6 @@ error: parameter of type `HashSet` should be generarized over different hashers
    |
 help: consider adding a type parameter
    |
-78 |         pub fn $name<S: ::std::hash::BuildHasher>(_map: &mut HashMap<i32, i32>, _set: &mut HashSet<i32>) {
+78 |         pub fn $name<S: ::std::hash::BuildHasher>(_map: &mut HashMap<i32, i32>, _set: &mut HashSet<i32, S>) {
    |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-help: ...and change the type to
-   |
-78 |         pub fn $name(_map: &mut HashMap<i32, i32>, _set: &mut HashSet<i32, S>) {
-   |                                                               ^^^^^^^^^^^^^^^
 

Original file line number	Diff line number	Diff line change
@@ -7,12 +7,8 @@ error: impl for `HashMap` should be generarized over different hashers
`7`	`7`	= note: `-D implicit-hasher` implied by `-D warnings`
`8`	`8`	`help: consider adding a type parameter`
`9`	`9`	`\|`
`10`		`-11 \| impl<K: Hash + Eq, V, S: ::std::hash::BuildHasher + Default> Foo<i8> for HashMap<K, V> {`
	`10`	`+11 \| impl<K: Hash + Eq, V, S: ::std::hash::BuildHasher + Default> Foo<i8> for HashMap<K, V, S> {`
`11`	`11`	`\| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^`
`12`		`-help: ...and change the type to`
`13`		`- \|`
`14`		`-11 \| impl<K: Hash + Eq, V> Foo<i8> for HashMap<K, V, S> {`
`15`		`- \| ^^^^^^^^^^^^^^^^`
`16`	`12`	`help: ...and use generic constructor`
`17`	`13`	`\|`
`18`	`14`	`17 \| (HashMap::default(), HashMap::with_capacity_and_hasher(10, Default::default()))`
@@ -26,12 +22,8 @@ error: impl for `HashMap` should be generarized over different hashers
`26`	`22`	`\|`
`27`	`23`	`help: consider adding a type parameter`
`28`	`24`	`\|`
`29`		`-20 \| impl<K: Hash + Eq, V, S: ::std::hash::BuildHasher + Default> Foo<i8> for (HashMap<K, V>,) {`
	`25`	`+20 \| impl<K: Hash + Eq, V, S: ::std::hash::BuildHasher + Default> Foo<i8> for (HashMap<K, V, S>,) {`
`30`	`26`	`\| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^`
`31`		`-help: ...and change the type to`
`32`		`- \|`
`33`		`-20 \| impl<K: Hash + Eq, V> Foo<i8> for (HashMap<K, V, S>,) {`
`34`		`- \| ^^^^^^^^^^^^^^^^`
`35`	`27`	`help: ...and use generic constructor`
`36`	`28`	`\|`
`37`	`29`	`22 \| ((HashMap::default(),), (HashMap::with_capacity_and_hasher(10, Default::default()),))`
@@ -45,12 +37,8 @@ error: impl for `HashMap` should be generarized over different hashers
`45`	`37`	`\|`
`46`	`38`	`help: consider adding a type parameter`
`47`	`39`	`\|`
`48`		`-25 \| impl<S: ::std::hash::BuildHasher + Default> Foo<i16> for HashMap<String, String> {`
	`40`	`+25 \| impl<S: ::std::hash::BuildHasher + Default> Foo<i16> for HashMap<String, String, S> {`
`49`	`41`	`\| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^`
`50`		`-help: ...and change the type to`
`51`		`- \|`
`52`		`-25 \| impl Foo<i16> for HashMap<String, String, S> {`
`53`		`- \| ^^^^^^^^^^^^^^^^^^^^^^^^^^`
`54`	`42`	`help: ...and use generic constructor`
`55`	`43`	`\|`
`56`	`44`	`27 \| (HashMap::default(), HashMap::with_capacity_and_hasher(10, Default::default()))`
@@ -64,12 +52,8 @@ error: impl for `HashSet` should be generarized over different hashers
`64`	`52`	`\|`
`65`	`53`	`help: consider adding a type parameter`
`66`	`54`	`\|`
`67`		`-43 \| impl<T: Hash + Eq, S: ::std::hash::BuildHasher + Default> Foo<i8> for HashSet<T> {`
	`55`	`+43 \| impl<T: Hash + Eq, S: ::std::hash::BuildHasher + Default> Foo<i8> for HashSet<T, S> {`
`68`	`56`	`\| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^`
`69`		`-help: ...and change the type to`
`70`		`- \|`
`71`		`-43 \| impl<T: Hash + Eq> Foo<i8> for HashSet<T, S> {`
`72`		`- \| ^^^^^^^^^^^^^`
`73`	`57`	`help: ...and use generic constructor`
`74`	`58`	`\|`
`75`	`59`	`45 \| (HashSet::default(), HashSet::with_capacity_and_hasher(10, Default::default()))`
@@ -83,12 +67,8 @@ error: impl for `HashSet` should be generarized over different hashers
`83`	`67`	`\|`
`84`	`68`	`help: consider adding a type parameter`
`85`	`69`	`\|`
`86`		`-48 \| impl<S: ::std::hash::BuildHasher + Default> Foo<i16> for HashSet<String> {`
	`70`	`+48 \| impl<S: ::std::hash::BuildHasher + Default> Foo<i16> for HashSet<String, S> {`
`87`	`71`	`\| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^`
`88`		`-help: ...and change the type to`
`89`		`- \|`
`90`		`-48 \| impl Foo<i16> for HashSet<String, S> {`
`91`		`- \| ^^^^^^^^^^^^^^^^^^`
`92`	`72`	`help: ...and use generic constructor`
`93`	`73`	`\|`
`94`	`74`	`50 \| (HashSet::default(), HashSet::with_capacity_and_hasher(10, Default::default()))`
@@ -102,12 +82,8 @@ error: parameter of type `HashMap` should be generarized over different hashers
`102`	`82`	`\|`
`103`	`83`	`help: consider adding a type parameter`
`104`	`84`	`\|`
`105`		`-65 \| pub fn foo<S: ::std::hash::BuildHasher>(_map: &mut HashMap<i32, i32>, _set: &mut HashSet<i32>) {`
	`85`	`+65 \| pub fn foo<S: ::std::hash::BuildHasher>(_map: &mut HashMap<i32, i32, S>, _set: &mut HashSet<i32>) {`
`106`	`86`	`\| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^`
`107`		`-help: ...and change the type to`
`108`		`- \|`
`109`		`-65 \| pub fn foo(_map: &mut HashMap<i32, i32, S>, _set: &mut HashSet<i32>) {`
`110`		`- \| ^^^^^^^^^^^^^^^^^^^^`
`111`	`87`
`112`	`88`	error: parameter of type `HashSet` should be generarized over different hashers
`113`	`89`	`--> $DIR/implicit_hasher.rs:65:53`
@@ -117,12 +93,8 @@ error: parameter of type `HashSet` should be generarized over different hashers
`117`	`93`	`\|`
`118`	`94`	`help: consider adding a type parameter`
`119`	`95`	`\|`
`120`		`-65 \| pub fn foo<S: ::std::hash::BuildHasher>(_map: &mut HashMap<i32, i32>, _set: &mut HashSet<i32>) {`
	`96`	`+65 \| pub fn foo<S: ::std::hash::BuildHasher>(_map: &mut HashMap<i32, i32>, _set: &mut HashSet<i32, S>) {`
`121`	`97`	`\| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^`
`122`		`-help: ...and change the type to`
`123`		`- \|`
`124`		`-65 \| pub fn foo(_map: &mut HashMap<i32, i32>, _set: &mut HashSet<i32, S>) {`
`125`		`- \| ^^^^^^^^^^^^^^^`
`126`	`98`
`127`	`99`	error: impl for `HashMap` should be generarized over different hashers
`128`	`100`	`--> $DIR/implicit_hasher.rs:70:43`
@@ -135,12 +107,8 @@ error: impl for `HashMap` should be generarized over different hashers
`135`	`107`	`\|`
`136`	`108`	`help: consider adding a type parameter`
`137`	`109`	`\|`
`138`		`-70 \| impl<K: Hash + Eq, V, S: ::std::hash::BuildHasher + Default> Foo<u8> for HashMap<K, V> {`
	`110`	`+70 \| impl<K: Hash + Eq, V, S: ::std::hash::BuildHasher + Default> Foo<u8> for HashMap<K, V, S> {`
`139`	`111`	`\| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^`
`140`		`-help: ...and change the type to`
`141`		`- \|`
`142`		`-70 \| impl<K: Hash + Eq, V> Foo<u8> for HashMap<K, V, S> {`
`143`		`- \| ^^^^^^^^^^^^^^^^`
`144`	`112`	`help: ...and use generic constructor`
`145`	`113`	`\|`
`146`	`114`	`72 \| (HashMap::default(), HashMap::with_capacity_and_hasher(10, Default::default()))`
@@ -157,12 +125,8 @@ error: parameter of type `HashMap` should be generarized over different hashers
`157`	`125`	`\|`
`158`	`126`	`help: consider adding a type parameter`
`159`	`127`	`\|`
`160`		`-78 \| pub fn $name<S: ::std::hash::BuildHasher>(_map: &mut HashMap<i32, i32>, _set: &mut HashSet<i32>) {`
	`128`	`+78 \| pub fn $name<S: ::std::hash::BuildHasher>(_map: &mut HashMap<i32, i32, S>, _set: &mut HashSet<i32>) {`
`161`	`129`	`\| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^`
`162`		`-help: ...and change the type to`
`163`		`- \|`
`164`		`-78 \| pub fn $name(_map: &mut HashMap<i32, i32, S>, _set: &mut HashSet<i32>) {`
`165`		`- \| ^^^^^^^^^^^^^^^^^^^^`
`166`	`130`
`167`	`131`	error: parameter of type `HashSet` should be generarized over different hashers
`168`	`132`	`--> $DIR/implicit_hasher.rs:78:63`
@@ -175,10 +139,6 @@ error: parameter of type `HashSet` should be generarized over different hashers
`175`	`139`	`\|`
`176`	`140`	`help: consider adding a type parameter`
`177`	`141`	`\|`
`178`		`-78 \| pub fn $name<S: ::std::hash::BuildHasher>(_map: &mut HashMap<i32, i32>, _set: &mut HashSet<i32>) {`
	`142`	`+78 \| pub fn $name<S: ::std::hash::BuildHasher>(_map: &mut HashMap<i32, i32>, _set: &mut HashSet<i32, S>) {`
`179`	`143`	`\| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^`
`180`		`-help: ...and change the type to`
`181`		`- \|`
`182`		`-78 \| pub fn $name(_map: &mut HashMap<i32, i32>, _set: &mut HashSet<i32, S>) {`
`183`		`- \| ^^^^^^^^^^^^^^^`
`184`	`144`