slightly improve no return for returning function error

Author: Rageking8

compiler/rustc_hir_analysis/src/check/fn_ctxt/suggestions.rs

@@ -1122,7 +1122,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             } else {
                 err.span_suggestion_short(
                     span_semi,
-                    "remove this semicolon",
+                    "remove this semicolon to return this value",
                     "",
                     Applicability::MachineApplicable,
                 );

src/test/ui/block-result/consider-removing-last-semi.stderr

@@ -7,7 +7,7 @@ LL | pub fn f() -> String {
    |        implicitly returns `()` as its body has no tail or `return` expression
 LL |     0u8;
 LL |     "bla".to_string();
-   |                      - help: remove this semicolon
+   |                      - help: remove this semicolon to return this value
 
 error[E0308]: mismatched types
   --> $DIR/consider-removing-last-semi.rs:8:15
@@ -18,7 +18,7 @@ LL | pub fn g() -> String {
    |        implicitly returns `()` as its body has no tail or `return` expression
 LL |     "this won't work".to_string();
 LL |     "removeme".to_string();
-   |                           - help: remove this semicolon
+   |                           - help: remove this semicolon to return this value
 
 error[E0308]: mismatched types
   --> $DIR/consider-removing-last-semi.rs:13:25
@@ -29,7 +29,7 @@ LL | pub fn macro_tests() -> u32 {
    |        implicitly returns `()` as its body has no tail or `return` expression
 ...
 LL |     mac!();
-   |           - help: remove this semicolon
+   |           - help: remove this semicolon to return this value
 
 error: aborting due to 3 previous errors
 

src/test/ui/block-result/issue-11714.stderr

@@ -7,7 +7,7 @@ LL | fn blah() -> i32 {
    |    implicitly returns `()` as its body has no tail or `return` expression
 ...
 LL |     ;
-   |     - help: remove this semicolon
+   |     - help: remove this semicolon to return this value
 
 error: aborting due to previous error
 

src/test/ui/block-result/issue-13428.stderr

@@ -15,7 +15,7 @@ LL | fn bar() -> String {
    |    implicitly returns `()` as its body has no tail or `return` expression
 LL |     "foobar".to_string()
 LL |     ;
-   |     - help: remove this semicolon
+   |     - help: remove this semicolon to return this value
 
 error: aborting due to 2 previous errors
 

src/test/ui/closures/old-closure-expression-remove-semicolon.fixed

@@ -7,6 +7,6 @@ fn foo() -> i32 {
 fn main() {
     let _x: i32 = {
         //~^ ERROR mismatched types
-        foo() //~ HELP remove this semicolon
+        foo() //~ HELP remove this semicolon to return this value
     };
 }

src/test/ui/closures/old-closure-expression-remove-semicolon.rs

@@ -7,6 +7,6 @@ fn foo() -> i32 {
 fn main() {
     let _x: i32 = {
         //~^ ERROR mismatched types
-        foo(); //~ HELP remove this semicolon
+        foo(); //~ HELP remove this semicolon to return this value
     };
 }

src/test/ui/closures/old-closure-expression-remove-semicolon.stderr

@@ -5,7 +5,7 @@ LL |       let _x: i32 = {
    |  ___________________^
 LL | |
 LL | |         foo();
-   | |              - help: remove this semicolon
+   | |              - help: remove this semicolon to return this value
 LL | |     };
    | |_____^ expected `i32`, found `()`
 

src/test/ui/coercion/coercion-missing-tail-expected-type.stderr

@@ -6,7 +6,7 @@ LL | fn plus_one(x: i32) -> i32 {
    |    |
    |    implicitly returns `()` as its body has no tail or `return` expression
 LL |     x + 1;
-   |          - help: remove this semicolon
+   |          - help: remove this semicolon to return this value
 
 error[E0308]: mismatched types
   --> $DIR/coercion-missing-tail-expected-type.rs:8:13
@@ -16,7 +16,7 @@ LL | fn foo() -> Result<u8, u64> {
    |    |
    |    implicitly returns `()` as its body has no tail or `return` expression
 LL |     Ok(1);
-   |          - help: remove this semicolon
+   |          - help: remove this semicolon to return this value
    |
    = note:   expected enum `Result<u8, u64>`
            found unit type `()`

src/test/ui/issues/issue-6458-4.stderr

@@ -6,7 +6,7 @@ LL | fn foo(b: bool) -> Result<bool,String> {
    |    |
    |    implicitly returns `()` as its body has no tail or `return` expression
 LL |     Err("bar".to_string());
-   |                           - help: remove this semicolon
+   |                           - help: remove this semicolon to return this value
    |
    = note:   expected enum `Result<bool, String>`
            found unit type `()`

src/test/ui/liveness/liveness-return-last-stmt-semi.rs

@@ -1,4 +1,3 @@
-//
 // regression test for #8005
 
 macro_rules! test { () => { fn foo() -> i32 { 1; } } }

src/test/ui/liveness/liveness-return-last-stmt-semi.stderr

@@ -1,31 +1,31 @@
 error[E0308]: mismatched types
-  --> $DIR/liveness-return-last-stmt-semi.rs:7:19
+  --> $DIR/liveness-return-last-stmt-semi.rs:6:19
    |
 LL | fn no_return() -> i32 {}
    |    ---------      ^^^ expected `i32`, found `()`
    |    |
    |    implicitly returns `()` as its body has no tail or `return` expression
 
 error[E0308]: mismatched types
-  --> $DIR/liveness-return-last-stmt-semi.rs:9:19
+  --> $DIR/liveness-return-last-stmt-semi.rs:8:19
    |
 LL | fn bar(x: u32) -> u32 {
    |    ---            ^^^ expected `u32`, found `()`
    |    |
    |    implicitly returns `()` as its body has no tail or `return` expression
 LL |     x * 2;
-   |          - help: remove this semicolon
+   |          - help: remove this semicolon to return this value
 
 error[E0308]: mismatched types
-  --> $DIR/liveness-return-last-stmt-semi.rs:13:19
+  --> $DIR/liveness-return-last-stmt-semi.rs:12:19
    |
 LL | fn baz(x: u64) -> u32 {
    |    ---            ^^^ expected `u32`, found `()`
    |    |
    |    implicitly returns `()` as its body has no tail or `return` expression
 
 error[E0308]: mismatched types
-  --> $DIR/liveness-return-last-stmt-semi.rs:4:41
+  --> $DIR/liveness-return-last-stmt-semi.rs:3:41
    |
 LL | macro_rules! test { () => { fn foo() -> i32 { 1; } } }
    |                                ---      ^^^ expected `i32`, found `()`

src/test/ui/suggestions/match-with-different-arm-types-as-stmt-instead-of-expr.stderr

@@ -7,7 +7,7 @@ LL | fn not_all_paths(a: &str) -> u32 {
    |    implicitly returns `()` as its body has no tail or `return` expression
 ...
 LL |     };
-   |      - help: remove this semicolon
+   |      - help: remove this semicolon to return this value
 
 error[E0308]: `match` arms have incompatible types
   --> $DIR/match-with-different-arm-types-as-stmt-instead-of-expr.rs:26:14