Remove noisy suggestion of hash_map #72642

Ayush Kumar Mishra · Ayush Kumar Mishra · commit 968594d7d37d · 2020-06-04T05:09:15.000+05:30
Update src/librustc_resolve/diagnostics.rs Co-authored-by: David Wood <Q0KPU0H1YOEPHRY1R2SN5B5RL@david.davidtw.co> Minor refactoring #72642 Fixed failing test-cases
diff --git a/src/librustc_resolve/diagnostics.rs b/src/librustc_resolve/diagnostics.rs
@@ -680,7 +680,9 @@ impl<'a> Resolver<'a> {
                                 Res::Def(DefKind::Ctor(..), did) => this.parent(did),
                                 _ => res.opt_def_id(),
                             };
-                            candidates.push(ImportSuggestion { did, descr: res.descr(), path });
+                            if candidates.iter().all(|v: &ImportSuggestion| v.did != did) {
+                                candidates.push(ImportSuggestion { did, descr: res.descr(), path });
+                            }
                         }
                     }
                 }
diff --git a/src/test/ui/issues/issue-17546.stderr b/src/test/ui/issues/issue-17546.stderr
@@ -30,11 +30,10 @@ LL |     use std::fmt::Result;
    |
 LL |     use std::io::Result;
    |
-LL |     use std::prelude::v1::Result;
-   |
 LL |     use std::result::Result;
    |
-     and 1 other candidate
+LL |     use std::thread::Result;
+   |
 
 error[E0573]: expected type, found variant `Result`
   --> $DIR/issue-17546.rs:30:13
@@ -48,11 +47,10 @@ LL | use std::fmt::Result;
    |
 LL | use std::io::Result;
    |
-LL | use std::prelude::v1::Result;
-   |
 LL | use std::result::Result;
    |
-     and 1 other candidate
+LL | use std::thread::Result;
+   |
 
 error[E0573]: expected type, found variant `NoResult`
   --> $DIR/issue-17546.rs:35:15
diff --git a/src/test/ui/no-implicit-prelude-nested.stderr b/src/test/ui/no-implicit-prelude-nested.stderr
@@ -15,35 +15,29 @@ error[E0404]: expected trait, found derive macro `Clone`
 LL |         impl Clone for Test {}
    |              ^^^^^ not a trait
    |
-help: consider importing one of these items instead
+help: consider importing this trait instead
    |
 LL |         use std::clone::Clone;
    |
-LL |         use std::prelude::v1::Clone;
-   |
 
 error[E0405]: cannot find trait `Iterator` in this scope
   --> $DIR/no-implicit-prelude-nested.rs:13:14
    |
 LL |         impl Iterator for Test {}
    |              ^^^^^^^^ not found in this scope
    |
-help: consider importing one of these items
+help: consider importing this trait
    |
 LL |         use std::iter::Iterator;
    |
-LL |         use std::prelude::v1::Iterator;
-   |
 
 error[E0405]: cannot find trait `ToString` in this scope
   --> $DIR/no-implicit-prelude-nested.rs:14:14
    |
 LL |         impl ToString for Test {}
    |              ^^^^^^^^ not found in this scope
    |
-help: consider importing one of these items
-   |
-LL |         use std::prelude::v1::ToString;
+help: consider importing this trait
    |
 LL |         use std::string::ToString;
    |
@@ -60,12 +54,10 @@ error[E0425]: cannot find function `drop` in this scope
 LL |             drop(2)
    |             ^^^^ not found in this scope
    |
-help: consider importing one of these items
+help: consider importing this function
    |
 LL |         use std::mem::drop;
    |
-LL |         use std::prelude::v1::drop;
-   |
 
 error[E0405]: cannot find trait `Add` in this scope
   --> $DIR/no-implicit-prelude-nested.rs:23:10
@@ -84,35 +76,29 @@ error[E0404]: expected trait, found derive macro `Clone`
 LL |     impl Clone for Test {}
    |          ^^^^^ not a trait
    |
-help: consider importing one of these items instead
+help: consider importing this trait instead
    |
 LL |     use std::clone::Clone;
    |
-LL |     use std::prelude::v1::Clone;
-   |
 
 error[E0405]: cannot find trait `Iterator` in this scope
   --> $DIR/no-implicit-prelude-nested.rs:25:10
    |
 LL |     impl Iterator for Test {}
    |          ^^^^^^^^ not found in this scope
    |
-help: consider importing one of these items
+help: consider importing this trait
    |
 LL |     use std::iter::Iterator;
    |
-LL |     use std::prelude::v1::Iterator;
-   |
 
 error[E0405]: cannot find trait `ToString` in this scope
   --> $DIR/no-implicit-prelude-nested.rs:26:10
    |
 LL |     impl ToString for Test {}
    |          ^^^^^^^^ not found in this scope
    |
-help: consider importing one of these items
-   |
-LL |     use std::prelude::v1::ToString;
+help: consider importing this trait
    |
 LL |     use std::string::ToString;
    |
@@ -129,12 +115,10 @@ error[E0425]: cannot find function `drop` in this scope
 LL |         drop(2)
    |         ^^^^ not found in this scope
    |
-help: consider importing one of these items
+help: consider importing this function
    |
 LL |     use std::mem::drop;
    |
-LL |     use std::prelude::v1::drop;
-   |
 
 error[E0405]: cannot find trait `Add` in this scope
   --> $DIR/no-implicit-prelude-nested.rs:38:14
@@ -153,35 +137,29 @@ error[E0404]: expected trait, found derive macro `Clone`
 LL |         impl Clone for Test {}
    |              ^^^^^ not a trait
    |
-help: consider importing one of these items instead
+help: consider importing this trait instead
    |
 LL |         use std::clone::Clone;
    |
-LL |         use std::prelude::v1::Clone;
-   |
 
 error[E0405]: cannot find trait `Iterator` in this scope
   --> $DIR/no-implicit-prelude-nested.rs:40:14
    |
 LL |         impl Iterator for Test {}
    |              ^^^^^^^^ not found in this scope
    |
-help: consider importing one of these items
+help: consider importing this trait
    |
 LL |         use std::iter::Iterator;
    |
-LL |         use std::prelude::v1::Iterator;
-   |
 
 error[E0405]: cannot find trait `ToString` in this scope
   --> $DIR/no-implicit-prelude-nested.rs:41:14
    |
 LL |         impl ToString for Test {}
    |              ^^^^^^^^ not found in this scope
    |
-help: consider importing one of these items
-   |
-LL |         use std::prelude::v1::ToString;
+help: consider importing this trait
    |
 LL |         use std::string::ToString;
    |
@@ -198,12 +176,10 @@ error[E0425]: cannot find function `drop` in this scope
 LL |             drop(2)
    |             ^^^^ not found in this scope
    |
-help: consider importing one of these items
+help: consider importing this function
    |
 LL |         use std::mem::drop;
    |
-LL |         use std::prelude::v1::drop;
-   |
 
 error: aborting due to 18 previous errors
 
diff --git a/src/test/ui/no-implicit-prelude.stderr b/src/test/ui/no-implicit-prelude.stderr
@@ -15,35 +15,29 @@ error[E0404]: expected trait, found derive macro `Clone`
 LL | impl Clone for Test {}
    |      ^^^^^ not a trait
    |
-help: consider importing one of these items instead
+help: consider importing this trait instead
    |
 LL | use std::clone::Clone;
    |
-LL | use std::prelude::v1::Clone;
-   |
 
 error[E0405]: cannot find trait `Iterator` in this scope
   --> $DIR/no-implicit-prelude.rs:12:6
    |
 LL | impl Iterator for Test {}
    |      ^^^^^^^^ not found in this scope
    |
-help: consider importing one of these items
+help: consider importing this trait
    |
 LL | use std::iter::Iterator;
    |
-LL | use std::prelude::v1::Iterator;
-   |
 
 error[E0405]: cannot find trait `ToString` in this scope
   --> $DIR/no-implicit-prelude.rs:13:6
    |
 LL | impl ToString for Test {}
    |      ^^^^^^^^ not found in this scope
    |
-help: consider importing one of these items
-   |
-LL | use std::prelude::v1::ToString;
+help: consider importing this trait
    |
 LL | use std::string::ToString;
    |
@@ -60,12 +54,10 @@ error[E0425]: cannot find function `drop` in this scope
 LL |     drop(2)
    |     ^^^^ not found in this scope
    |
-help: consider importing one of these items
+help: consider importing this function
    |
 LL | use std::mem::drop;
    |
-LL | use std::prelude::v1::drop;
-   |
 
 error: aborting due to 6 previous errors
 
diff --git a/src/test/ui/resolve/use_suggestion_placement.stderr b/src/test/ui/resolve/use_suggestion_placement.stderr
@@ -26,12 +26,10 @@ error[E0412]: cannot find type `HashMap` in this scope
 LL |     type Dict<K, V> = HashMap<K, V>;
    |                       ^^^^^^^ not found in this scope
    |
-help: consider importing one of these items
+help: consider importing this struct
    |
 LL | use std::collections::HashMap;
    |
-LL | use std::collections::hash_map::HashMap;
-   |
 
 error: aborting due to 3 previous errors
 

Original file line number	Diff line number	Diff line change
`@@ -680,7 +680,9 @@ impl<'a> Resolver<'a> {`
`680`	`680`	`Res::Def(DefKind::Ctor(..), did) => this.parent(did),`
`681`	`681`	`_ => res.opt_def_id(),`
`682`	`682`	`};`
`683`		`- candidates.push(ImportSuggestion { did, descr: res.descr(), path });`
	`683`	`+ if candidates.iter().all(\|v: &ImportSuggestion\| v.did != did) {`
	`684`	`+ candidates.push(ImportSuggestion { did, descr: res.descr(), path });`
	`685`	`+ }`
`684`	`686`	`}`
`685`	`687`	`}`
`686`	`688`	`}`
Original file line number	Diff line number	Diff line change
`@@ -30,11 +30,10 @@ LL \| use std::fmt::Result;`
`30`	`30`	`\|`
`31`	`31`	`LL \| use std::io::Result;`
`32`	`32`	`\|`
`33`		`-LL \| use std::prelude::v1::Result;`
`34`		`- \|`
`35`	`33`	`LL \| use std::result::Result;`
`36`	`34`	`\|`
`37`		`- and 1 other candidate`
	`35`	`+LL \| use std::thread::Result;`
	`36`	`+ \|`
`38`	`37`
`39`	`38`	error[E0573]: expected type, found variant `Result`
`40`	`39`	`--> $DIR/issue-17546.rs:30:13`
`@@ -48,11 +47,10 @@ LL \| use std::fmt::Result;`
`48`	`47`	`\|`
`49`	`48`	`LL \| use std::io::Result;`
`50`	`49`	`\|`
`51`		`-LL \| use std::prelude::v1::Result;`
`52`		`- \|`
`53`	`50`	`LL \| use std::result::Result;`
`54`	`51`	`\|`
`55`		`- and 1 other candidate`
	`52`	`+LL \| use std::thread::Result;`
	`53`	`+ \|`
`56`	`54`
`57`	`55`	error[E0573]: expected type, found variant `NoResult`
`58`	`56`	`--> $DIR/issue-17546.rs:35:15`
Original file line number	Diff line number	Diff line change
@@ -15,35 +15,29 @@ error[E0404]: expected trait, found derive macro `Clone`
`15`	`15`	`LL \| impl Clone for Test {}`
`16`	`16`	`\| ^^^^^ not a trait`
`17`	`17`	`\|`
`18`		`-help: consider importing one of these items instead`
	`18`	`+help: consider importing this trait instead`
`19`	`19`	`\|`
`20`	`20`	`LL \| use std::clone::Clone;`
`21`	`21`	`\|`
`22`		`-LL \| use std::prelude::v1::Clone;`
`23`		`- \|`
`24`	`22`
`25`	`23`	error[E0405]: cannot find trait `Iterator` in this scope
`26`	`24`	`--> $DIR/no-implicit-prelude-nested.rs:13:14`
`27`	`25`	`\|`
`28`	`26`	`LL \| impl Iterator for Test {}`
`29`	`27`	`\| ^^^^^^^^ not found in this scope`
`30`	`28`	`\|`
`31`		`-help: consider importing one of these items`
	`29`	`+help: consider importing this trait`
`32`	`30`	`\|`
`33`	`31`	`LL \| use std::iter::Iterator;`
`34`	`32`	`\|`
`35`		`-LL \| use std::prelude::v1::Iterator;`
`36`		`- \|`
`37`	`33`
`38`	`34`	error[E0405]: cannot find trait `ToString` in this scope
`39`	`35`	`--> $DIR/no-implicit-prelude-nested.rs:14:14`
`40`	`36`	`\|`
`41`	`37`	`LL \| impl ToString for Test {}`
`42`	`38`	`\| ^^^^^^^^ not found in this scope`
`43`	`39`	`\|`
`44`		`-help: consider importing one of these items`
`45`		`- \|`
`46`		`-LL \| use std::prelude::v1::ToString;`
	`40`	`+help: consider importing this trait`
`47`	`41`	`\|`
`48`	`42`	`LL \| use std::string::ToString;`
`49`	`43`	`\|`
@@ -60,12 +54,10 @@ error[E0425]: cannot find function `drop` in this scope
`60`	`54`	`LL \| drop(2)`
`61`	`55`	`\| ^^^^ not found in this scope`
`62`	`56`	`\|`
`63`		`-help: consider importing one of these items`
	`57`	`+help: consider importing this function`
`64`	`58`	`\|`
`65`	`59`	`LL \| use std::mem::drop;`
`66`	`60`	`\|`
`67`		`-LL \| use std::prelude::v1::drop;`
`68`		`- \|`
`69`	`61`
`70`	`62`	error[E0405]: cannot find trait `Add` in this scope
`71`	`63`	`--> $DIR/no-implicit-prelude-nested.rs:23:10`
@@ -84,35 +76,29 @@ error[E0404]: expected trait, found derive macro `Clone`
`84`	`76`	`LL \| impl Clone for Test {}`
`85`	`77`	`\| ^^^^^ not a trait`
`86`	`78`	`\|`
`87`		`-help: consider importing one of these items instead`
	`79`	`+help: consider importing this trait instead`
`88`	`80`	`\|`
`89`	`81`	`LL \| use std::clone::Clone;`
`90`	`82`	`\|`
`91`		`-LL \| use std::prelude::v1::Clone;`
`92`		`- \|`
`93`	`83`
`94`	`84`	error[E0405]: cannot find trait `Iterator` in this scope
`95`	`85`	`--> $DIR/no-implicit-prelude-nested.rs:25:10`
`96`	`86`	`\|`
`97`	`87`	`LL \| impl Iterator for Test {}`
`98`	`88`	`\| ^^^^^^^^ not found in this scope`
`99`	`89`	`\|`
`100`		`-help: consider importing one of these items`
	`90`	`+help: consider importing this trait`
`101`	`91`	`\|`
`102`	`92`	`LL \| use std::iter::Iterator;`
`103`	`93`	`\|`
`104`		`-LL \| use std::prelude::v1::Iterator;`
`105`		`- \|`
`106`	`94`
`107`	`95`	error[E0405]: cannot find trait `ToString` in this scope
`108`	`96`	`--> $DIR/no-implicit-prelude-nested.rs:26:10`
`109`	`97`	`\|`
`110`	`98`	`LL \| impl ToString for Test {}`
`111`	`99`	`\| ^^^^^^^^ not found in this scope`
`112`	`100`	`\|`
`113`		`-help: consider importing one of these items`
`114`		`- \|`
`115`		`-LL \| use std::prelude::v1::ToString;`
	`101`	`+help: consider importing this trait`
`116`	`102`	`\|`
`117`	`103`	`LL \| use std::string::ToString;`
`118`	`104`	`\|`
@@ -129,12 +115,10 @@ error[E0425]: cannot find function `drop` in this scope
`129`	`115`	`LL \| drop(2)`
`130`	`116`	`\| ^^^^ not found in this scope`
`131`	`117`	`\|`
`132`		`-help: consider importing one of these items`
	`118`	`+help: consider importing this function`
`133`	`119`	`\|`
`134`	`120`	`LL \| use std::mem::drop;`
`135`	`121`	`\|`
`136`		`-LL \| use std::prelude::v1::drop;`
`137`		`- \|`
`138`	`122`
`139`	`123`	error[E0405]: cannot find trait `Add` in this scope
`140`	`124`	`--> $DIR/no-implicit-prelude-nested.rs:38:14`
@@ -153,35 +137,29 @@ error[E0404]: expected trait, found derive macro `Clone`
`153`	`137`	`LL \| impl Clone for Test {}`
`154`	`138`	`\| ^^^^^ not a trait`
`155`	`139`	`\|`
`156`		`-help: consider importing one of these items instead`
	`140`	`+help: consider importing this trait instead`
`157`	`141`	`\|`
`158`	`142`	`LL \| use std::clone::Clone;`
`159`	`143`	`\|`
`160`		`-LL \| use std::prelude::v1::Clone;`
`161`		`- \|`
`162`	`144`
`163`	`145`	error[E0405]: cannot find trait `Iterator` in this scope
`164`	`146`	`--> $DIR/no-implicit-prelude-nested.rs:40:14`
`165`	`147`	`\|`
`166`	`148`	`LL \| impl Iterator for Test {}`
`167`	`149`	`\| ^^^^^^^^ not found in this scope`
`168`	`150`	`\|`
`169`		`-help: consider importing one of these items`
	`151`	`+help: consider importing this trait`
`170`	`152`	`\|`
`171`	`153`	`LL \| use std::iter::Iterator;`
`172`	`154`	`\|`
`173`		`-LL \| use std::prelude::v1::Iterator;`
`174`		`- \|`
`175`	`155`
`176`	`156`	error[E0405]: cannot find trait `ToString` in this scope
`177`	`157`	`--> $DIR/no-implicit-prelude-nested.rs:41:14`
`178`	`158`	`\|`
`179`	`159`	`LL \| impl ToString for Test {}`
`180`	`160`	`\| ^^^^^^^^ not found in this scope`
`181`	`161`	`\|`
`182`		`-help: consider importing one of these items`
`183`		`- \|`
`184`		`-LL \| use std::prelude::v1::ToString;`
	`162`	`+help: consider importing this trait`
`185`	`163`	`\|`
`186`	`164`	`LL \| use std::string::ToString;`
`187`	`165`	`\|`
@@ -198,12 +176,10 @@ error[E0425]: cannot find function `drop` in this scope
`198`	`176`	`LL \| drop(2)`
`199`	`177`	`\| ^^^^ not found in this scope`
`200`	`178`	`\|`
`201`		`-help: consider importing one of these items`
	`179`	`+help: consider importing this function`
`202`	`180`	`\|`
`203`	`181`	`LL \| use std::mem::drop;`
`204`	`182`	`\|`
`205`		`-LL \| use std::prelude::v1::drop;`
`206`		`- \|`
`207`	`183`
`208`	`184`	`error: aborting due to 18 previous errors`
`209`	`185`
Original file line number	Diff line number	Diff line change
@@ -26,12 +26,10 @@ error[E0412]: cannot find type `HashMap` in this scope
`26`	`26`	`LL \| type Dict<K, V> = HashMap<K, V>;`
`27`	`27`	`\| ^^^^^^^ not found in this scope`
`28`	`28`	`\|`
`29`		`-help: consider importing one of these items`
	`29`	`+help: consider importing this struct`
`30`	`30`	`\|`
`31`	`31`	`LL \| use std::collections::HashMap;`
`32`	`32`	`\|`
`33`		`-LL \| use std::collections::hash_map::HashMap;`
`34`		`- \|`
`35`	`33`
`36`	`34`	`error: aborting due to 3 previous errors`
`37`	`35`