Tweak error for invalid `break expr`

Point at loop head on invalid `break expr`.
Suggest removing `expr` or using label if available.

5 files changed, 119 insertions, 55 deletions

diff --git a/src/test/ui/label/label_misspelled.rs b/src/test/ui/label/label_misspelled.rs
index 7a8ff0360f6..17c709768d5 100644
--- a/src/test/ui/label/label_misspelled.rs
+++ b/src/test/ui/label/label_misspelled.rs
@@ -1,8 +1,4 @@
 fn main() {
-    'LOOP: loop {
-        LOOP;
-        //~^ ERROR cannot find value `LOOP` in this scope
-    };
     'while_loop: while true { //~ WARN denote infinite loops with
         while_loop;
         //~^ ERROR cannot find value `while_loop` in this scope
@@ -15,6 +11,10 @@ fn main() {
         for_loop;
         //~^ ERROR cannot find value `for_loop` in this scope
     };
+    'LOOP: loop {
+        LOOP;
+        //~^ ERROR cannot find value `LOOP` in this scope
+    };
 }
 
 fn foo() {
@@ -25,16 +25,29 @@ fn foo() {
     'while_loop: while true { //~ WARN denote infinite loops with
         break while_loop;
         //~^ ERROR cannot find value `while_loop` in this scope
-        //~| ERROR `break` with value from a `while` loop
     };
     'while_let: while let Some(_) = Some(()) {
         break while_let;
         //~^ ERROR cannot find value `while_let` in this scope
-        //~| ERROR `break` with value from a `while` loop
     }
     'for_loop: for _ in 0..3 {
         break for_loop;
         //~^ ERROR cannot find value `for_loop` in this scope
-        //~| ERROR `break` with value from a `for` loop
+    };
+}
+
+fn bar() {
+    let foo = ();
+    'while_loop: while true { //~ WARN denote infinite loops with
+        break foo;
+        //~^ ERROR `break` with value from a `while` loop
+    };
+    'while_let: while let Some(_) = Some(()) {
+        break foo;
+        //~^ ERROR `break` with value from a `while` loop
+    }
+    'for_loop: for _ in 0..3 {
+        break foo;
+        //~^ ERROR `break` with value from a `for` loop
     };
 }
diff --git a/src/test/ui/label/label_misspelled.stderr b/src/test/ui/label/label_misspelled.stderr
index 7cfb6e8147d..3e99b0ff979 100644
--- a/src/test/ui/label/label_misspelled.stderr
+++ b/src/test/ui/label/label_misspelled.stderr
@@ -1,13 +1,5 @@
-error[E0425]: cannot find value `LOOP` in this scope
-  --> $DIR/label_misspelled.rs:3:9
-   |
-LL |     'LOOP: loop {
-   |     ----- a label with a similar name exists
-LL |         LOOP;
-   |         ^^^^ not found in this scope
-
 error[E0425]: cannot find value `while_loop` in this scope
-  --> $DIR/label_misspelled.rs:7:9
+  --> $DIR/label_misspelled.rs:3:9
    |
 LL |     'while_loop: while true {
    |     ----------- a label with a similar name exists
@@ -15,7 +7,7 @@ LL |         while_loop;
    |         ^^^^^^^^^^ not found in this scope
 
 error[E0425]: cannot find value `while_let` in this scope
-  --> $DIR/label_misspelled.rs:11:9
+  --> $DIR/label_misspelled.rs:7:9
    |
 LL |     'while_let: while let Some(_) = Some(()) {
    |     ---------- a label with a similar name exists
@@ -23,7 +15,7 @@ LL |         while_let;
    |         ^^^^^^^^^ not found in this scope
 
 error[E0425]: cannot find value `for_loop` in this scope
-  --> $DIR/label_misspelled.rs:15:9
+  --> $DIR/label_misspelled.rs:11:9
    |
 LL |     'for_loop: for _ in 0..3 {
    |     --------- a label with a similar name exists
@@ -31,6 +23,14 @@ LL |         for_loop;
    |         ^^^^^^^^ not found in this scope
 
 error[E0425]: cannot find value `LOOP` in this scope
+  --> $DIR/label_misspelled.rs:15:9
+   |
+LL |     'LOOP: loop {
+   |     ----- a label with a similar name exists
+LL |         LOOP;
+   |         ^^^^ not found in this scope
+
+error[E0425]: cannot find value `LOOP` in this scope
   --> $DIR/label_misspelled.rs:22:15
    |
 LL |     'LOOP: loop {
@@ -53,7 +53,7 @@ LL |         break while_loop;
    |               help: use the similarly named label: `'while_loop`
 
 error[E0425]: cannot find value `while_let` in this scope
-  --> $DIR/label_misspelled.rs:31:15
+  --> $DIR/label_misspelled.rs:30:15
    |
 LL |     'while_let: while let Some(_) = Some(()) {
    |     ---------- a label with a similar name exists
@@ -64,7 +64,7 @@ LL |         break while_let;
    |               help: use the similarly named label: `'while_let`
 
 error[E0425]: cannot find value `for_loop` in this scope
-  --> $DIR/label_misspelled.rs:36:15
+  --> $DIR/label_misspelled.rs:34:15
    |
 LL |     'for_loop: for _ in 0..3 {
    |     --------- a label with a similar name exists
@@ -75,7 +75,7 @@ LL |         break for_loop;
    |               help: use the similarly named label: `'for_loop`
 
 warning: denote infinite loops with `loop { ... }`
-  --> $DIR/label_misspelled.rs:6:5
+  --> $DIR/label_misspelled.rs:2:5
    |
 LL |     'while_loop: while true {
    |     ^^^^^^^^^^^^^^^^^^^^^^^ help: use `loop`
@@ -88,40 +88,64 @@ warning: denote infinite loops with `loop { ... }`
 LL |     'while_loop: while true {
    |     ^^^^^^^^^^^^^^^^^^^^^^^ help: use `loop`
 
+warning: denote infinite loops with `loop { ... }`
+  --> $DIR/label_misspelled.rs:41:5
+   |
+LL |     'while_loop: while true {
+   |     ^^^^^^^^^^^^^^^^^^^^^^^ help: use `loop`
+
 error[E0571]: `break` with value from a `while` loop
-  --> $DIR/label_misspelled.rs:26:9
+  --> $DIR/label_misspelled.rs:42:9
    |
-LL |         break while_loop;
-   |         ^^^^^^^^^^^^^^^^ can only break with a value inside `loop` or breakable block
+LL |     'while_loop: while true {
+   |     ----------------------- you can't `break` with a value in a `while` loop
+LL |         break foo;
+   |         ^^^^^^^^^ can only break with a value inside `loop` or breakable block
    |
-help: instead, use `break` on its own without a value inside this `while` loop
+help: use `break` on its own without a value inside this `while` loop
    |
 LL |         break;
    |         ^^^^^
+help: alternatively, you might have meant to use the available loop label
+   |
+LL |         break 'while_loop;
+   |               ^^^^^^^^^^^
 
 error[E0571]: `break` with value from a `while` loop
-  --> $DIR/label_misspelled.rs:31:9
+  --> $DIR/label_misspelled.rs:46:9
    |
-LL |         break while_let;
-   |         ^^^^^^^^^^^^^^^ can only break with a value inside `loop` or breakable block
+LL |     'while_let: while let Some(_) = Some(()) {
+   |     ---------------------------------------- you can't `break` with a value in a `while` loop
+LL |         break foo;
+   |         ^^^^^^^^^ can only break with a value inside `loop` or breakable block
    |
-help: instead, use `break` on its own without a value inside this `while` loop
+help: use `break` on its own without a value inside this `while` loop
    |
 LL |         break;
    |         ^^^^^
+help: alternatively, you might have meant to use the available loop label
+   |
+LL |         break 'while_let;
+   |               ^^^^^^^^^^
 
 error[E0571]: `break` with value from a `for` loop
-  --> $DIR/label_misspelled.rs:36:9
+  --> $DIR/label_misspelled.rs:50:9
    |
-LL |         break for_loop;
-   |         ^^^^^^^^^^^^^^ can only break with a value inside `loop` or breakable block
+LL |     'for_loop: for _ in 0..3 {
+   |     ------------------------ you can't `break` with a value in a `for` loop
+LL |         break foo;
+   |         ^^^^^^^^^ can only break with a value inside `loop` or breakable block
    |
-help: instead, use `break` on its own without a value inside this `for` loop
+help: use `break` on its own without a value inside this `for` loop
    |
 LL |         break;
    |         ^^^^^
+help: alternatively, you might have meant to use the available loop label
+   |
+LL |         break 'for_loop;
+   |               ^^^^^^^^^
 
-error: aborting due to 11 previous errors; 2 warnings emitted
+error: aborting due to 11 previous errors; 3 warnings emitted
 
 Some errors have detailed explanations: E0425, E0571.
 For more information about an error, try `rustc --explain E0425`.
diff --git a/src/test/ui/loops/loop-break-value-no-repeat.stderr b/src/test/ui/loops/loop-break-value-no-repeat.stderr
index ff93e9220e9..1c0d39a6e5a 100644
--- a/src/test/ui/loops/loop-break-value-no-repeat.stderr
+++ b/src/test/ui/loops/loop-break-value-no-repeat.stderr
@@ -1,10 +1,12 @@
 error[E0571]: `break` with value from a `for` loop
   --> $DIR/loop-break-value-no-repeat.rs:12:9
    |
+LL |     for _ in &[1,2,3] {
+   |     ----------------- you can't `break` with a value in a `for` loop
 LL |         break 22
    |         ^^^^^^^^ can only break with a value inside `loop` or breakable block
    |
-help: instead, use `break` on its own without a value inside this `for` loop
+help: use `break` on its own without a value inside this `for` loop
    |
 LL |         break
    |         ^^^^^
diff --git a/src/test/ui/loops/loop-break-value.rs b/src/test/ui/loops/loop-break-value.rs
index 8a080cfdf49..51c9a36a039 100644
--- a/src/test/ui/loops/loop-break-value.rs
+++ b/src/test/ui/loops/loop-break-value.rs
@@ -94,6 +94,5 @@ fn main() {
     'LOOP: for _ in 0 .. 9 {
         break LOOP;
         //~^ ERROR cannot find value `LOOP` in this scope
-        //~| ERROR `break` with value from a `for` loop
     }
 }
diff --git a/src/test/ui/loops/loop-break-value.stderr b/src/test/ui/loops/loop-break-value.stderr
index 27104118a63..c7cf1017d4b 100644
--- a/src/test/ui/loops/loop-break-value.stderr
+++ b/src/test/ui/loops/loop-break-value.stderr
@@ -20,32 +20,48 @@ LL |     'while_loop: while true {
 error[E0571]: `break` with value from a `while` loop
   --> $DIR/loop-break-value.rs:28:9
    |
+LL |     'while_loop: while true {
+   |     ----------------------- you can't `break` with a value in a `while` loop
+LL |         break;
 LL |         break ();
    |         ^^^^^^^^ can only break with a value inside `loop` or breakable block
    |
-help: instead, use `break` on its own without a value inside this `while` loop
+help: use `break` on its own without a value inside this `while` loop
    |
 LL |         break;
    |         ^^^^^
+help: alternatively, you might have meant to use the available loop label
+   |
+LL |         break 'while_loop;
+   |               ^^^^^^^^^^^
 
 error[E0571]: `break` with value from a `while` loop
   --> $DIR/loop-break-value.rs:30:13
    |
+LL |     'while_loop: while true {
+   |     ----------------------- you can't `break` with a value in a `while` loop
+...
 LL |             break 'while_loop 123;
    |             ^^^^^^^^^^^^^^^^^^^^^ can only break with a value inside `loop` or breakable block
    |
-help: instead, use `break` on its own without a value inside this `while` loop
+help: use `break` on its own without a value inside this `while` loop
    |
 LL |             break;
    |             ^^^^^
+help: alternatively, you might have meant to use the available loop label
+   |
+LL |             break 'while_loop 'while_loop;
+   |                               ^^^^^^^^^^^
 
 error[E0571]: `break` with value from a `while` loop
   --> $DIR/loop-break-value.rs:38:12
    |
+LL |     while let Some(_) = Some(()) {
+   |     ---------------------------- you can't `break` with a value in a `while` loop
 LL |         if break () {
    |            ^^^^^^^^ can only break with a value inside `loop` or breakable block
    |
-help: instead, use `break` on its own without a value inside this `while` loop
+help: use `break` on its own without a value inside this `while` loop
    |
 LL |         if break {
    |            ^^^^^
@@ -53,10 +69,12 @@ LL |         if break {
 error[E0571]: `break` with value from a `while` loop
   --> $DIR/loop-break-value.rs:43:9
    |
+LL |     while let Some(_) = Some(()) {
+   |     ---------------------------- you can't `break` with a value in a `while` loop
 LL |         break None;
    |         ^^^^^^^^^^ can only break with a value inside `loop` or breakable block
    |
-help: instead, use `break` on its own without a value inside this `while` loop
+help: use `break` on its own without a value inside this `while` loop
    |
 LL |         break;
    |         ^^^^^
@@ -64,21 +82,30 @@ LL |         break;
 error[E0571]: `break` with value from a `while` loop
   --> $DIR/loop-break-value.rs:49:13
    |
+LL |     'while_let_loop: while let Some(_) = Some(()) {
+   |     --------------------------------------------- you can't `break` with a value in a `while` loop
+LL |         loop {
 LL |             break 'while_let_loop "nope";
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ can only break with a value inside `loop` or breakable block
    |
-help: instead, use `break` on its own without a value inside this `while` loop
+help: use `break` on its own without a value inside this `while` loop
    |
 LL |             break;
    |             ^^^^^
+help: alternatively, you might have meant to use the available loop label
+   |
+LL |             break 'while_let_loop 'while_let_loop;
+   |                                   ^^^^^^^^^^^^^^^
 
 error[E0571]: `break` with value from a `for` loop
   --> $DIR/loop-break-value.rs:56:9
    |
+LL |     for _ in &[1,2,3] {
+   |     ----------------- you can't `break` with a value in a `for` loop
 LL |         break ();
    |         ^^^^^^^^ can only break with a value inside `loop` or breakable block
    |
-help: instead, use `break` on its own without a value inside this `for` loop
+help: use `break` on its own without a value inside this `for` loop
    |
 LL |         break;
    |         ^^^^^
@@ -86,10 +113,13 @@ LL |         break;
 error[E0571]: `break` with value from a `for` loop
   --> $DIR/loop-break-value.rs:57:9
    |
+LL |     for _ in &[1,2,3] {
+   |     ----------------- you can't `break` with a value in a `for` loop
+LL |         break ();
 LL |         break [()];
    |         ^^^^^^^^^^ can only break with a value inside `loop` or breakable block
    |
-help: instead, use `break` on its own without a value inside this `for` loop
+help: use `break` on its own without a value inside this `for` loop
    |
 LL |         break;
    |         ^^^^^
@@ -97,24 +127,20 @@ LL |         break;
 error[E0571]: `break` with value from a `for` loop
   --> $DIR/loop-break-value.rs:64:13
    |
+LL |     'for_loop: for _ in &[1,2,3] {
+   |     ---------------------------- you can't `break` with a value in a `for` loop
+...
 LL |             break 'for_loop Some(17);
    |             ^^^^^^^^^^^^^^^^^^^^^^^^ can only break with a value inside `loop` or breakable block
    |
-help: instead, use `break` on its own without a value inside this `for` loop
+help: use `break` on its own without a value inside this `for` loop
    |
 LL |             break;
    |             ^^^^^
-
-error[E0571]: `break` with value from a `for` loop
-  --> $DIR/loop-break-value.rs:95:9
-   |
-LL |         break LOOP;
-   |         ^^^^^^^^^^ can only break with a value inside `loop` or breakable block
+help: alternatively, you might have meant to use the available loop label
    |
-help: instead, use `break` on its own without a value inside this `for` loop
-   |
-LL |         break;
-   |         ^^^^^
+LL |             break 'for_loop 'for_loop;
+   |                             ^^^^^^^^^
 
 error[E0308]: mismatched types
   --> $DIR/loop-break-value.rs:4:31
@@ -173,7 +199,7 @@ LL |         break;
    |         expected integer, found `()`
    |         help: give it a value of the expected type: `break value`
 
-error: aborting due to 18 previous errors; 1 warning emitted
+error: aborting due to 17 previous errors; 1 warning emitted
 
 Some errors have detailed explanations: E0308, E0425, E0571.
 For more information about an error, try `rustc --explain E0308`.