Auto merge of #32263 - frewsxcv:compiletest-ignored-expected, r=nikomatsakis

Stop ignoring expected note/help messages in compiletest suite.

Original issue: https://github.com/rust-lang/rust/issues/21195

Relevant PR: https://github.com/rust-lang/rust/pull/30778

Prior to this commit, if a compiletest testcase included the text
"HELP:" or "NOTE:" (note the colons), then it would indicate to the
compiletest suite that we should verify "help" and "note" expected
messages.

This commit updates this check to also check "HELP" and "NOTE" (not the
absense of colons) so that we always verify "help" and "note" expected
messages.

46 files changed, 141 insertions, 6 deletions

diff --git a/src/compiletest/runtest.rs b/src/compiletest/runtest.rs
index 8c3ee3fb5f4..be011107c50 100644
--- a/src/compiletest/runtest.rs
+++ b/src/compiletest/runtest.rs
@@ -1013,8 +1013,8 @@ fn check_expected_errors(revision: Option<&str>,
         expected_errors.iter()
                         .fold((false, false),
                               |(acc_help, acc_note), ee|
-                                  (acc_help || ee.kind == "help:", acc_note ||
-                                   ee.kind == "note:"));
+                                  (acc_help || ee.kind == "help:" || ee.kind == "help",
+                                   acc_note || ee.kind == "note:" || ee.kind == "note"));
 
     // Scan and extract our error/warning messages,
     // which look like:
diff --git a/src/test/compile-fail/asm-out-assign-imm.rs b/src/test/compile-fail/asm-out-assign-imm.rs
index 8c8451623d5..c1c72a5519b 100644
--- a/src/test/compile-fail/asm-out-assign-imm.rs
+++ b/src/test/compile-fail/asm-out-assign-imm.rs
@@ -23,6 +23,7 @@ pub fn main() {
     unsafe {
         asm!("mov $1, $0" : "=r"(x) : "r"(5));
         //~^ ERROR re-assignment of immutable variable `x`
+        //~| NOTE in this expansion of asm!
     }
     foo(x);
 }
diff --git a/src/test/compile-fail/borrowck/borrowck-box-insensitivity.rs b/src/test/compile-fail/borrowck/borrowck-box-insensitivity.rs
index c980e77df6f..7c3d632078f 100644
--- a/src/test/compile-fail/borrowck/borrowck-box-insensitivity.rs
+++ b/src/test/compile-fail/borrowck/borrowck-box-insensitivity.rs
@@ -54,80 +54,97 @@ fn borrow_after_move() {
 fn move_after_borrow() {
     let a: Box<_> = box B { x: box 0, y: box 1 };
     let _x = &a.x;
+    //~^ NOTE borrow of `a.x` occurs here
     let _y = a.y; //~ ERROR cannot move
 }
 
 fn copy_after_mut_borrow() {
     let mut a: Box<_> = box A { x: box 0, y: 1 };
     let _x = &mut a.x;
+    //~^ NOTE borrow of `a.x` occurs here
     let _y = a.y; //~ ERROR cannot use
 }
 
 fn move_after_mut_borrow() {
     let mut a: Box<_> = box B { x: box 0, y: box 1 };
     let _x = &mut a.x;
+    //~^ NOTE borrow of `a.x` occurs here
     let _y = a.y; //~ ERROR cannot move
 }
 
 fn borrow_after_mut_borrow() {
     let mut a: Box<_> = box A { x: box 0, y: 1 };
     let _x = &mut a.x;
+    //~^ NOTE previous borrow of `a` occurs here (through borrowing `a.x`);
     let _y = &a.y; //~ ERROR cannot borrow
 }
+//~^ NOTE previous borrow ends here
 
 fn mut_borrow_after_borrow() {
     let mut a: Box<_> = box A { x: box 0, y: 1 };
     let _x = &a.x;
+    //~^ NOTE previous borrow of `a` occurs here (through borrowing `a.x`)
     let _y = &mut a.y; //~ ERROR cannot borrow
 }
+//~^ NOTE previous borrow ends here
 
 fn copy_after_move_nested() {
     let a: Box<_> = box C { x: box A { x: box 0, y: 1 }, y: 2 };
     let _x = a.x.x;
+    //~^ NOTE `a.x.x` moved here because it has type `Box<isize>`, which is moved by default
     let _y = a.y; //~ ERROR use of collaterally moved
 }
 
 fn move_after_move_nested() {
     let a: Box<_> = box D { x: box A { x: box 0, y: 1 }, y: box 2 };
     let _x = a.x.x;
+    //~^ NOTE `a.x.x` moved here because it has type `Box<isize>`, which is moved by default
     let _y = a.y; //~ ERROR use of collaterally moved
 }
 
 fn borrow_after_move_nested() {
     let a: Box<_> = box C { x: box A { x: box 0, y: 1 }, y: 2 };
     let _x = a.x.x;
+    //~^ NOTE `a.x.x` moved here because it has type `Box<isize>`, which is moved by default
     let _y = &a.y; //~ ERROR use of collaterally moved
 }
 
 fn move_after_borrow_nested() {
     let a: Box<_> = box D { x: box A { x: box 0, y: 1 }, y: box 2 };
     let _x = &a.x.x;
+    //~^ NOTE borrow of `a.x.x` occurs here
     let _y = a.y; //~ ERROR cannot move
 }
 
 fn copy_after_mut_borrow_nested() {
     let mut a: Box<_> = box C { x: box A { x: box 0, y: 1 }, y: 2 };
     let _x = &mut a.x.x;
+    //~^ NOTE borrow of `a.x.x` occurs here
     let _y = a.y; //~ ERROR cannot use
 }
 
 fn move_after_mut_borrow_nested() {
     let mut a: Box<_> = box D { x: box A { x: box 0, y: 1 }, y: box 2 };
     let _x = &mut a.x.x;
+    //~^ NOTE borrow of `a.x.x` occurs here
     let _y = a.y; //~ ERROR cannot move
 }
 
 fn borrow_after_mut_borrow_nested() {
     let mut a: Box<_> = box C { x: box A { x: box 0, y: 1 }, y: 2 };
     let _x = &mut a.x.x;
+    //~^ NOTE previous borrow of `a.x.x` occurs here; the mutable borrow prevents
     let _y = &a.y; //~ ERROR cannot borrow
 }
+//~^ NOTE previous borrow ends here
 
 fn mut_borrow_after_borrow_nested() {
     let mut a: Box<_> = box C { x: box A { x: box 0, y: 1 }, y: 2 };
     let _x = &a.x.x;
+    //~^ NOTE previous borrow of `a.x.x` occurs here; the immutable borrow prevents
     let _y = &mut a.y; //~ ERROR cannot borrow
 }
+//~^ NOTE previous borrow ends here
 
 fn main() {
     copy_after_move();
diff --git a/src/test/compile-fail/borrowck/borrowck-let-suggestion.rs b/src/test/compile-fail/borrowck/borrowck-let-suggestion.rs
index d760f3db0c2..7e9d448275d 100644
--- a/src/test/compile-fail/borrowck/borrowck-let-suggestion.rs
+++ b/src/test/compile-fail/borrowck/borrowck-let-suggestion.rs
@@ -12,6 +12,7 @@ fn f() {
     let x = [1].iter(); //~ ERROR borrowed value does not live long enough
                          //~^ NOTE reference must be valid for the block suffix following statement
                          //~^^ HELP consider using a `let` binding to increase its lifetime
+                         //~^^^ NOTE ...but borrowed value is only valid for the statement at 12:4
 }
 
 fn main() {
diff --git a/src/test/compile-fail/borrowck/borrowck-report-with-custom-diagnostic.rs b/src/test/compile-fail/borrowck/borrowck-report-with-custom-diagnostic.rs
index 61bf2c11a1f..2b1ff47ee3d 100644
--- a/src/test/compile-fail/borrowck/borrowck-report-with-custom-diagnostic.rs
+++ b/src/test/compile-fail/borrowck/borrowck-report-with-custom-diagnostic.rs
@@ -13,6 +13,7 @@ fn main() {
     // Original borrow ends at end of function
     let mut x = 1;
     let y = &mut x;
+    //~^ previous borrow of `x` occurs here; the mutable borrow prevents
     let z = &x; //~ ERROR cannot borrow
 }
 //~^ NOTE previous borrow ends here
@@ -23,6 +24,7 @@ fn foo() {
             // Original borrow ends at end of match arm
             let mut x = 1;
             let y = &x;
+            //~^ previous borrow of `x` occurs here; the immutable borrow prevents
             let z = &mut x; //~ ERROR cannot borrow
         }
      //~^ NOTE previous borrow ends here
@@ -35,6 +37,7 @@ fn bar() {
     || {
         let mut x = 1;
         let y = &mut x;
+        //~^ previous borrow of `x` occurs here; the mutable borrow prevents
         let z = &mut x; //~ ERROR cannot borrow
     };
  //~^ NOTE previous borrow ends here
diff --git a/src/test/compile-fail/borrowck/borrowck-vec-pattern-nesting.rs b/src/test/compile-fail/borrowck/borrowck-vec-pattern-nesting.rs
index a69ce0cb365..1a21b03a457 100644
--- a/src/test/compile-fail/borrowck/borrowck-vec-pattern-nesting.rs
+++ b/src/test/compile-fail/borrowck/borrowck-vec-pattern-nesting.rs
@@ -17,6 +17,7 @@ fn a() {
     let mut vec = [box 1, box 2, box 3];
     match vec {
         [box ref _a, _, _] => {
+        //~^ borrow of `vec[..]` occurs here
             vec[0] = box 4; //~ ERROR cannot assign
         }
     }
@@ -27,6 +28,7 @@ fn b() {
     let vec: &mut [Box<isize>] = &mut vec;
     match vec {
         [_b..] => {
+        //~^ borrow of `vec[..]` occurs here
             vec[0] = box 4; //~ ERROR cannot assign
         }
     }
@@ -48,6 +50,7 @@ fn c() {
         _ => {}
     }
     let a = vec[0]; //~ ERROR cannot move out
+    //~^ NOTE attempting to move value to here
 }
 
 fn d() {
@@ -59,6 +62,7 @@ fn d() {
         _ => {}
     }
     let a = vec[0]; //~ ERROR cannot move out
+    //~^ NOTE attempting to move value to here
 }
 
 fn e() {
diff --git a/src/test/compile-fail/cast-as-bool.rs b/src/test/compile-fail/cast-as-bool.rs
index 52a4950022d..4764ae380ff 100644
--- a/src/test/compile-fail/cast-as-bool.rs
+++ b/src/test/compile-fail/cast-as-bool.rs
@@ -12,4 +12,5 @@ fn main() {
     let u = 5 as bool;
     //~^ ERROR cannot cast as `bool`
     //~^^ HELP compare with zero instead
+    //~^^^ HELP run `rustc --explain E0054` to see a detailed explanation
 }
diff --git a/src/test/compile-fail/cast-rfc0401.rs b/src/test/compile-fail/cast-rfc0401.rs
index 8e129722722..b458334006a 100644
--- a/src/test/compile-fail/cast-rfc0401.rs
+++ b/src/test/compile-fail/cast-rfc0401.rs
@@ -61,9 +61,11 @@ fn main()
     let _ = 3 as bool;
     //~^ ERROR cannot cast as `bool`
     //~^^ HELP compare with zero
+    //~^^^ HELP run `rustc --explain E0054` to see a detailed explanation
     let _ = E::A as bool;
     //~^ ERROR cannot cast as `bool`
     //~^^ HELP compare with zero
+    //~^^^ HELP run `rustc --explain E0054` to see a detailed explanation
     let _ = 0x61u32 as char; //~ ERROR only `u8` can be cast
 
     let _ = false as f32;
@@ -90,6 +92,9 @@ fn main()
     let _ = v as *const [u8]; //~ ERROR cannot cast
     let _ = fat_v as *const Foo;
     //~^ ERROR `core::marker::Sized` is not implemented for the type `[u8]`
+    //~^^ HELP run `rustc --explain E0277` to see a detailed explanation
+    //~^^^ NOTE `[u8]` does not have a constant size known at compile-time
+    //~^^^^ NOTE required for the cast to the object type `Foo`
     let _ = foo as *const str; //~ ERROR casting
     let _ = foo as *mut str; //~ ERROR casting
     let _ = main as *mut str; //~ ERROR casting
@@ -102,6 +107,9 @@ fn main()
     let a : *const str = "hello";
     let _ = a as *const Foo;
     //~^ ERROR `core::marker::Sized` is not implemented for the type `str`
+    //~^^ HELP run `rustc --explain E0277` to see a detailed explanation
+    //~^^^ NOTE `str` does not have a constant size known at compile-time
+    //~^^^^ NOTE required for the cast to the object type `Foo`
 
     // check no error cascade
     let _ = main.f as *const u32; //~ ERROR attempted access of field
diff --git a/src/test/compile-fail/fat-ptr-cast.rs b/src/test/compile-fail/fat-ptr-cast.rs
index c920b6c171e..b2fd11d4b39 100644
--- a/src/test/compile-fail/fat-ptr-cast.rs
+++ b/src/test/compile-fail/fat-ptr-cast.rs
@@ -18,6 +18,7 @@ fn main() {
     let q = a.as_ptr();
 
     a as usize; //~ ERROR casting
+    //~^ HELP cast through a raw pointer first
     b as usize; //~ ERROR non-scalar cast
     p as usize;
     //~^ ERROR casting
diff --git a/src/test/compile-fail/feature-gate-negate-unsigned.rs b/src/test/compile-fail/feature-gate-negate-unsigned.rs
index 546fc5e3c60..4330a4cbeab 100644
--- a/src/test/compile-fail/feature-gate-negate-unsigned.rs
+++ b/src/test/compile-fail/feature-gate-negate-unsigned.rs
@@ -23,5 +23,6 @@ const _MAX: usize = -1;
 fn main() {
     let x = 5u8;
     let _y = -x; //~ ERROR unary negation of unsigned integer
+    //~^ HELP use a cast or the `!` operator
     -S; // should not trigger the gate; issue 26840
 }
diff --git a/src/test/compile-fail/issue-11714.rs b/src/test/compile-fail/issue-11714.rs
index 998576097a0..6dde59d4a2e 100644
--- a/src/test/compile-fail/issue-11714.rs
+++ b/src/test/compile-fail/issue-11714.rs
@@ -9,6 +9,7 @@
 // except according to those terms.
 
 fn blah() -> i32 { //~ ERROR not all control paths return a value
+    //~^ HELP run `rustc --explain E0269` to see a detailed explanation
     1
 
     ; //~ HELP consider removing this semicolon:
diff --git a/src/test/compile-fail/issue-13058.rs b/src/test/compile-fail/issue-13058.rs
index 8886dd80be5..503ccbd1cab 100644
--- a/src/test/compile-fail/issue-13058.rs
+++ b/src/test/compile-fail/issue-13058.rs
@@ -40,4 +40,5 @@ fn main() {
 //~| found `(_, _)`
 //~| expected &-ptr
 //~| found tuple
+//~| HELP run `rustc --explain E0308` to see a detailed explanation
 }
diff --git a/src/test/compile-fail/issue-13428.rs b/src/test/compile-fail/issue-13428.rs
index c771970650d..5b8ab08aefc 100644
--- a/src/test/compile-fail/issue-13428.rs
+++ b/src/test/compile-fail/issue-13428.rs
@@ -11,6 +11,7 @@
 // Regression test for #13428
 
 fn foo() -> String {  //~ ERROR not all control paths return a value
+    //~^ HELP run `rustc --explain E0269` to see a detailed explanation
     format!("Hello {}",
             "world")
     // Put the trailing semicolon on its own line to test that the
@@ -19,6 +20,7 @@ fn foo() -> String {  //~ ERROR not all control paths return a value
 }
 
 fn bar() -> String {  //~ ERROR not all control paths return a value
+    //~^ HELP run `rustc --explain E0269` to see a detailed explanation
     "foobar".to_string()
     ;   //~ HELP consider removing this semicolon
 }
diff --git a/src/test/compile-fail/issue-15260.rs b/src/test/compile-fail/issue-15260.rs
index 2228b6d3779..5ec82326d6c 100644
--- a/src/test/compile-fail/issue-15260.rs
+++ b/src/test/compile-fail/issue-15260.rs
@@ -25,6 +25,7 @@ fn main() {
 
     let Foo {
         a, //~ NOTE field `a` previously bound here
+        //~^ NOTE field `a` previously bound here
         a: _, //~ ERROR field `a` bound multiple times in the pattern
         a: x //~ ERROR field `a` bound multiple times in the pattern
     } = Foo { a: 29 };
diff --git a/src/test/compile-fail/issue-16747.rs b/src/test/compile-fail/issue-16747.rs
index dd7e8a869ec..0fdb5f74e82 100644
--- a/src/test/compile-fail/issue-16747.rs
+++ b/src/test/compile-fail/issue-16747.rs
@@ -19,6 +19,7 @@ struct List<'a, T: ListItem<'a>> {
 //~^ ERROR the parameter type `T` may not live long enough
 //~| HELP consider adding an explicit lifetime bound
 //~| NOTE ...so that the reference type `&'a [T]` does not outlive the data it points at
+//~| HELP run `rustc --explain E0309` to see a detailed explanation
 }
 impl<'a, T: ListItem<'a>> Collection for List<'a, T> {
     fn len(&self) -> usize {
diff --git a/src/test/compile-fail/issue-17263.rs b/src/test/compile-fail/issue-17263.rs
index f40d51f1d2f..2320bc02baf 100644
--- a/src/test/compile-fail/issue-17263.rs
+++ b/src/test/compile-fail/issue-17263.rs
@@ -23,3 +23,5 @@ fn main() {
     //~^ ERROR cannot borrow `foo` (here through borrowing `foo.b`) as immutable
     //~^^ NOTE previous borrow of `foo` occurs here (through borrowing `foo.a`)
 }
+//~^ NOTE previous borrow ends here
+//~^^ NOTE previous borrow ends here
diff --git a/src/test/compile-fail/issue-19707.rs b/src/test/compile-fail/issue-19707.rs
index 9affb44b744..814c1a4131d 100644
--- a/src/test/compile-fail/issue-19707.rs
+++ b/src/test/compile-fail/issue-19707.rs
@@ -13,8 +13,10 @@
 
 type foo = fn(&u8, &u8) -> &u8; //~ ERROR missing lifetime specifier
 //~^ HELP the signature does not say whether it is borrowed from argument 1 or argument 2
+//~^^ HELP run `rustc --explain E0106` to see a detailed explanation
 
 fn bar<F: Fn(&u8, &u8) -> &u8>(f: &F) {} //~ ERROR missing lifetime specifier
 //~^ HELP the signature does not say whether it is borrowed from argument 1 or argument 2
+//~^^ HELP run `rustc --explain E0106` to see a detailed explanation
 
 fn main() {}
diff --git a/src/test/compile-fail/issue-21221-1.rs b/src/test/compile-fail/issue-21221-1.rs
index 03dd7b6754a..c53d5a0922e 100644
--- a/src/test/compile-fail/issue-21221-1.rs
+++ b/src/test/compile-fail/issue-21221-1.rs
@@ -55,6 +55,8 @@ impl Mul for Foo {
 //~| HELP `mul1::Mul`
 //~| HELP `mul2::Mul`
 //~| HELP `std::ops::Mul`
+//~| HELP run `rustc --explain E0405` to see a detailed explanation
+//~| HELP you can import several candidates into scope (`use ...;`):
 }
 
 // BEFORE, we got:
@@ -75,17 +77,22 @@ fn getMul() -> Mul {
 //~| HELP `mul3::Mul`
 //~| HELP `mul4::Mul`
 //~| HELP and 2 other candidates
+//~| HELP run `rustc --explain E0412` to see a detailed explanation
+//~| HELP you can import several candidates into scope (`use ...;`):
 }
 
 // Let's also test what happens if the trait doesn't exist:
 impl ThisTraitReallyDoesntExistInAnyModuleReally for Foo {
 //~^ ERROR trait `ThisTraitReallyDoesntExistInAnyModuleReally` is not in scope
+//~^^ HELP run `rustc --explain E0405` to see a detailed explanation
+//~^^^ HELP no candidates by the name of `ThisTraitReallyDoesntExistInAnyModuleReally` found
 }
 
 // Let's also test what happens if there's just one alternative:
 impl Div for Foo {
 //~^ ERROR trait `Div` is not in scope
 //~| HELP `use std::ops::Div;`
+//~| HELP run `rustc --explain E0405` to see a detailed explanation
 }
 
 fn main() {
diff --git a/src/test/compile-fail/issue-21221-2.rs b/src/test/compile-fail/issue-21221-2.rs
index 8c2c27694d9..f031b62214d 100644
--- a/src/test/compile-fail/issue-21221-2.rs
+++ b/src/test/compile-fail/issue-21221-2.rs
@@ -28,3 +28,4 @@ struct Foo;
 impl T for Foo { }
 //~^ ERROR trait `T` is not in scope
 //~| HELP you can to import it into scope: `use foo::bar::T;`.
+//~| HELP run `rustc --explain E0405` to see a detailed explanation
diff --git a/src/test/compile-fail/issue-21221-3.rs b/src/test/compile-fail/issue-21221-3.rs
index ba66496b930..eee2c016451 100644
--- a/src/test/compile-fail/issue-21221-3.rs
+++ b/src/test/compile-fail/issue-21221-3.rs
@@ -25,6 +25,7 @@ struct Foo;
 impl OuterTrait for Foo {}
 //~^ ERROR trait `OuterTrait` is not in scope
 //~| HELP you can to import it into scope: `use issue_21221_3::outer::OuterTrait;`.
+//~| HELP run `rustc --explain E0405` to see a detailed explanation
 fn main() {
     println!("Hello, world!");
 }
diff --git a/src/test/compile-fail/issue-21221-4.rs b/src/test/compile-fail/issue-21221-4.rs
index 8d09510ae09..6a76264dff7 100644
--- a/src/test/compile-fail/issue-21221-4.rs
+++ b/src/test/compile-fail/issue-21221-4.rs
@@ -20,6 +20,7 @@ struct Foo;
 impl T for Foo {}
 //~^ ERROR trait `T` is not in scope
 //~| HELP you can to import it into scope: `use issue_21221_4::T;`.
+//~| HELP run `rustc --explain E0405` to see a detailed explanation
 
 fn main() {
     println!("Hello, world!");
diff --git a/src/test/compile-fail/issue-21600.rs b/src/test/compile-fail/issue-21600.rs
index f9a79dbb9c3..d9dcebfda6a 100644
--- a/src/test/compile-fail/issue-21600.rs
+++ b/src/test/compile-fail/issue-21600.rs
@@ -23,5 +23,8 @@ fn main() {
         call_it(|| x.gen());
         call_it(|| x.gen_mut()); //~ ERROR cannot borrow data mutably in a captured outer
         //~^ ERROR cannot borrow data mutably in a captured outer
+        //~^^ HELP run `rustc --explain E0387` to see a detailed explanation
+        //~^^^ HELP run `rustc --explain E0387` to see a detailed explanation
+        //~^^^^ HELP consider changing this closure to take self by mutable reference
     });
 }
diff --git a/src/test/compile-fail/issue-24036.rs b/src/test/compile-fail/issue-24036.rs
index 3c8a64eaf7d..28eebea749c 100644
--- a/src/test/compile-fail/issue-24036.rs
+++ b/src/test/compile-fail/issue-24036.rs
@@ -14,17 +14,20 @@ fn closure_to_loc() {
     //~^ ERROR mismatched types
     //~| NOTE no two closures, even if identical, have the same type
     //~| HELP consider boxing your closure and/or using it as a trait object
+    //~| HELP run `rustc --explain E0308` to see a detailed explanation
 }
 
 fn closure_from_match() {
     let x = match 1usize {
         1 => |c| c + 1,
         2 => |c| c - 1,
+        //~^ NOTE match arm with an incompatible type
         _ => |c| c - 1
     };
-    //~^^^^^ ERROR match arms have incompatible types
+    //~^^^^^^ ERROR match arms have incompatible types
     //~| NOTE no two closures, even if identical, have the same type
     //~| HELP consider boxing your closure and/or using it as a trait object
+    //~| HELP run `rustc --explain E0308` to see a detailed explanation
 }
 
 fn main() { }
diff --git a/src/test/compile-fail/issue-25385.rs b/src/test/compile-fail/issue-25385.rs
index 4aacb6840e9..51d7baaf3e9 100644
--- a/src/test/compile-fail/issue-25385.rs
+++ b/src/test/compile-fail/issue-25385.rs
@@ -21,4 +21,5 @@ fn main() {
 
     foo!(1i32.foo());
     //~^ ERROR no method named `foo` found for type `i32` in the current scope
+    //~^^ NOTE in this expansion of foo!
 }
diff --git a/src/test/compile-fail/issue-25386.rs b/src/test/compile-fail/issue-25386.rs
index 297d3aacfd5..b2775db5e75 100644
--- a/src/test/compile-fail/issue-25386.rs
+++ b/src/test/compile-fail/issue-25386.rs
@@ -35,6 +35,4 @@ macro_rules! check_ptr_exist {
 fn main() {
     let item = stuff::Item::new();
     println!("{}", check_ptr_exist!(item, name));
-    //~^ NOTE in this expansion of check_ptr_exist!
-    //~^^ NOTE in this expansion of check_ptr_exist!
 }
diff --git a/src/test/compile-fail/issue-25793.rs b/src/test/compile-fail/issue-25793.rs
index fd3e3186bc5..44b3ada97fe 100644
--- a/src/test/compile-fail/issue-25793.rs
+++ b/src/test/compile-fail/issue-25793.rs
@@ -27,6 +27,7 @@ impl HasInfo {
     fn get_other(&mut self) -> usize {
         self.get_size(width!(self))
         //~^ NOTE in this expansion of width!
+        //~| NOTE borrow of `*self` occurs here
     }
 }
 
diff --git a/src/test/compile-fail/issue-26638.rs b/src/test/compile-fail/issue-26638.rs
index 010803bf25b..9cbb64c2311 100644
--- a/src/test/compile-fail/issue-26638.rs
+++ b/src/test/compile-fail/issue-26638.rs
@@ -11,13 +11,18 @@
 fn parse_type(iter: Box<Iterator<Item=&str>+'static>) -> &str { iter.next() }
 //~^ ERROR missing lifetime specifier [E0106]
 //~^^ HELP 2 elided lifetimes
+//~^^^ HELP run `rustc --explain E0106` to see a detailed explanation
 
 fn parse_type_2(iter: fn(&u8)->&u8) -> &str { iter() }
 //~^ ERROR missing lifetime specifier [E0106]
 //~^^ HELP lifetime cannot be derived
+//~^^^ HELP run `rustc --explain E0106` to see a detailed explanation
+//~^^^^ HELP consider giving it an explicit bounded or 'static lifetime
 
 fn parse_type_3() -> &str { unimplemented!() }
 //~^ ERROR missing lifetime specifier [E0106]
 //~^^ HELP no value for it to be borrowed from
+//~^^^ HELP run `rustc --explain E0106` to see a detailed explanation
+//~^^^^ HELP consider giving it a 'static lifetime
 
 fn main() {}
diff --git a/src/test/compile-fail/issue-30302.rs b/src/test/compile-fail/issue-30302.rs
index 26508a47224..56f0b31da0d 100644
--- a/src/test/compile-fail/issue-30302.rs
+++ b/src/test/compile-fail/issue-30302.rs
@@ -18,8 +18,10 @@ fn is_empty<T>(s: Stack<T>) -> bool {
         Nil => true,
 //~^ WARN pattern binding `Nil` is named the same as one of the variants of the type `Stack`
 //~| HELP consider making the path in the pattern qualified: `Stack::Nil`
+//~| HELP run `rustc --explain E0170` to see a detailed explanation
         _ => false
 //~^ ERROR unreachable pattern
+//~| HELP run `rustc --explain E0001` to see a detailed explanation
     }
 }
 
diff --git a/src/test/compile-fail/issue-6702.rs b/src/test/compile-fail/issue-6702.rs
index 66ed817ffa8..6cb825a9be7 100644
--- a/src/test/compile-fail/issue-6702.rs
+++ b/src/test/compile-fail/issue-6702.rs
@@ -16,4 +16,5 @@ struct Monster {
 fn main() {
     let _m = Monster(); //~ ERROR `Monster` is the name of a struct or
     //~^ HELP did you mean to write: `Monster { /* fields */ }`?
+    //~| HELP run `rustc --explain E0423` to see a detailed explanation
 }
diff --git a/src/test/compile-fail/lifetime-elision-return-type-requires-explicit-lifetime.rs b/src/test/compile-fail/lifetime-elision-return-type-requires-explicit-lifetime.rs
index 1fa7284f6b5..be4166e43b5 100644
--- a/src/test/compile-fail/lifetime-elision-return-type-requires-explicit-lifetime.rs
+++ b/src/test/compile-fail/lifetime-elision-return-type-requires-explicit-lifetime.rs
@@ -11,12 +11,15 @@
 // Lifetime annotation needed because we have no arguments.
 fn f() -> &isize {    //~ ERROR missing lifetime specifier
 //~^ HELP there is no value for it to be borrowed from
+//~| HELP run `rustc --explain E0106` to see a detailed explanation
+//~| HELP consider giving it a 'static lifetime
     panic!()
 }
 
 // Lifetime annotation needed because we have two by-reference parameters.
 fn g(_x: &isize, _y: &isize) -> &isize {    //~ ERROR missing lifetime specifier
 //~^ HELP the signature does not say whether it is borrowed from `_x` or `_y`
+//~| HELP run `rustc --explain E0106` to see a detailed explanation
     panic!()
 }
 
@@ -28,11 +31,14 @@ struct Foo<'a> {
 // and one on the reference.
 fn h(_x: &Foo) -> &isize { //~ ERROR missing lifetime specifier
 //~^ HELP the signature does not say which one of `_x`'s 2 elided lifetimes it is borrowed from
+//~| HELP run `rustc --explain E0106` to see a detailed explanation
     panic!()
 }
 
 fn i(_x: isize) -> &isize { //~ ERROR missing lifetime specifier
 //~^ HELP this function's return type contains a borrowed value
+//~| HELP run `rustc --explain E0106` to see a detailed explanation
+//~| HELP consider giving it an explicit bounded or 'static lifetime
     panic!()
 }
 
diff --git a/src/test/compile-fail/lint-group-style.rs b/src/test/compile-fail/lint-group-style.rs
index 59ab5be1572..393e46ab539 100644
--- a/src/test/compile-fail/lint-group-style.rs
+++ b/src/test/compile-fail/lint-group-style.rs
@@ -30,6 +30,7 @@ mod test {
     mod warn {
         #![warn(bad_style)]
         //~^ NOTE lint level defined here
+        //~| NOTE lint level defined here
 
         fn CamelCase() {} //~ WARN function `CamelCase` should have a snake case name
 
diff --git a/src/test/compile-fail/lint-no-drop-on-repr-extern.rs b/src/test/compile-fail/lint-no-drop-on-repr-extern.rs
index 2df57b08f28..91e5065517d 100644
--- a/src/test/compile-fail/lint-no-drop-on-repr-extern.rs
+++ b/src/test/compile-fail/lint-no-drop-on-repr-extern.rs
@@ -15,6 +15,8 @@
 
 #![feature(unsafe_no_drop_flag)]
 #![deny(drop_with_repr_extern)]
+//~^ NOTE lint level defined here
+//~| NOTE lint level defined here
 
 #[repr(C)] struct As { x: Box<i8> }
 #[repr(C)] enum Ae { Ae(Box<i8>), _None }
diff --git a/src/test/compile-fail/lint-unconditional-recursion.rs b/src/test/compile-fail/lint-unconditional-recursion.rs
index 6e3a00746f3..94e189aa47f 100644
--- a/src/test/compile-fail/lint-unconditional-recursion.rs
+++ b/src/test/compile-fail/lint-unconditional-recursion.rs
@@ -9,6 +9,20 @@
 // except according to those terms.
 
 #![deny(unconditional_recursion)]
+//~^ NOTE lint level defined here
+//~| NOTE lint level defined here
+//~| NOTE lint level defined here
+//~| NOTE lint level defined here
+//~| NOTE lint level defined here
+//~| NOTE lint level defined here
+//~| NOTE lint level defined here
+//~| NOTE lint level defined here
+//~| NOTE lint level defined here
+//~| NOTE lint level defined here
+//~| NOTE lint level defined here
+//~| NOTE lint level defined here
+//~| NOTE lint level defined here
+//~| NOTE lint level defined here
 #![allow(dead_code)]
 fn foo() { //~ ERROR function cannot return without recurring
     foo(); //~ NOTE recursive call site
diff --git a/src/test/compile-fail/liveness-return-last-stmt-semi.rs b/src/test/compile-fail/liveness-return-last-stmt-semi.rs
index a4eb1630afe..343622c5c1b 100644
--- a/src/test/compile-fail/liveness-return-last-stmt-semi.rs
+++ b/src/test/compile-fail/liveness-return-last-stmt-semi.rs
@@ -13,14 +13,18 @@
 macro_rules! test { () => { fn foo() -> i32 { 1; } } }
                                            //~^ ERROR not all control paths return a value
                                            //~^^ HELP consider removing this semicolon
+                                           //~^^^ HELP run `rustc --explain E0269` to see a
 
 fn no_return() -> i32 {} //~ ERROR  not all control paths return a value
+                         //~^ HELP run `rustc --explain E0269` to see a detailed explanation
 
 fn bar(x: u32) -> u32 { //~ ERROR  not all control paths return a value
+                        //~^ HELP run `rustc --explain E0269` to see a detailed explanation
     x * 2; //~ HELP consider removing this semicolon
 }
 
 fn baz(x: u64) -> u32 { //~ ERROR  not all control paths return a value
+                        //~^ HELP run `rustc --explain E0269` to see a detailed explanation
     x * 2;
 }
 
diff --git a/src/test/compile-fail/macro-backtrace-nested.rs b/src/test/compile-fail/macro-backtrace-nested.rs
index a429681bb21..c935ccef055 100644
--- a/src/test/compile-fail/macro-backtrace-nested.rs
+++ b/src/test/compile-fail/macro-backtrace-nested.rs
@@ -21,9 +21,11 @@ macro_rules! call_nested_expr {
 
 macro_rules! call_nested_expr_sum {
     () => { 1 + nested_expr!(); } //~ ERROR unresolved name
+                                  //~^ NOTE in this expansion of nested_expr!
 }
 
 fn main() {
     1 + call_nested_expr!(); //~ ERROR unresolved name
+                             //~^ NOTE in this expansion of call_nested_expr!
     call_nested_expr_sum!(); //~ NOTE in this expansion of
 }
diff --git a/src/test/compile-fail/macro-backtrace-println.rs b/src/test/compile-fail/macro-backtrace-println.rs
index 294892662d4..a485b9056de 100644
--- a/src/test/compile-fail/macro-backtrace-println.rs
+++ b/src/test/compile-fail/macro-backtrace-println.rs
@@ -22,7 +22,8 @@ macro_rules! myprint {
 
 macro_rules! myprintln {
     ($fmt:expr) => (myprint!(concat!($fmt, "\n"))); //~ ERROR invalid reference to argument `0`
-                                                    //~^ NOTE in this expansion of
+                                                    //~^ NOTE in this expansion of myprint!
+                                                    //~^^ NOTE in this expansion of concat!
 }
 
 fn main() {
diff --git a/src/test/compile-fail/method-suggestion-no-duplication.rs b/src/test/compile-fail/method-suggestion-no-duplication.rs
index e6f3c8ab317..c8c1447fea3 100644
--- a/src/test/compile-fail/method-suggestion-no-duplication.rs
+++ b/src/test/compile-fail/method-suggestion-no-duplication.rs
@@ -9,6 +9,7 @@
 // except according to those terms.
 
 // issue #21405
+// ignore-tidy-linelength
 
 struct Foo;
 
@@ -19,4 +20,5 @@ fn main() {
     //~^ ERROR no method named `is_empty` found
     //~^^ HELP #1: `core::slice::SliceExt`
     //~^^^ HELP #2: `core::str::StrExt`
+    //~^^^^ HELP items from traits can only be used if the trait is implemented and in scope; the following traits define an item `is_empty`, perhaps you need to implement one of them:
 }
diff --git a/src/test/compile-fail/object-safety-generics.rs b/src/test/compile-fail/object-safety-generics.rs
index 8e3161ef884..5097e3d7b10 100644
--- a/src/test/compile-fail/object-safety-generics.rs
+++ b/src/test/compile-fail/object-safety-generics.rs
@@ -29,6 +29,7 @@ fn make_bar<T:Bar>(t: &T) -> &Bar {
 
 fn make_bar_explicit<T:Bar>(t: &T) -> &Bar {
     //~^ ERROR E0038
+    //~^^ NOTE method `bar` has generic type parameters
     t as &Bar
 }
 
diff --git a/src/test/compile-fail/on-unimplemented.rs b/src/test/compile-fail/on-unimplemented.rs
index c4eb467c4f9..f386e7cdd5a 100644
--- a/src/test/compile-fail/on-unimplemented.rs
+++ b/src/test/compile-fail/on-unimplemented.rs
@@ -34,6 +34,8 @@ pub fn main() {
     let y: Option<Vec<u8>> = collect(x.iter()); // this should give approximately the same error for x.iter().collect()
     //~^ ERROR
     //~^^ NOTE a collection of type `core::option::Option<collections::vec::Vec<u8>>` cannot be built from an iterator over elements of type `&u8`
+    //~^^^ NOTE required by `collect`
     let x: String = foobar(); //~ ERROR
     //~^ NOTE test error `collections::string::String` with `u8` `_` `u32`
+    //~^^ NOTE required by `foobar`
 }
diff --git a/src/test/compile-fail/recursion_limit.rs b/src/test/compile-fail/recursion_limit.rs
index 368269999a2..226a6d57ddb 100644
--- a/src/test/compile-fail/recursion_limit.rs
+++ b/src/test/compile-fail/recursion_limit.rs
@@ -43,4 +43,15 @@ fn main() {
     is_send::<A>();
     //~^ ERROR overflow evaluating
     //~| NOTE consider adding a `#![recursion_limit="20"]` attribute to your crate
+    //~| NOTE required because it appears within the type `A`
+    //~| NOTE required because it appears within the type `B`
+    //~| NOTE required because it appears within the type `C`
+    //~| NOTE required because it appears within the type `D`
+    //~| NOTE required because it appears within the type `E`
+    //~| NOTE required because it appears within the type `F`
+    //~| NOTE required because it appears within the type `G`
+    //~| NOTE required because it appears within the type `H`
+    //~| NOTE required because it appears within the type `I`
+    //~| NOTE required because it appears within the type `J`
+    //~| NOTE required by `is_send`
 }
diff --git a/src/test/compile-fail/ref-suggestion.rs b/src/test/compile-fail/ref-suggestion.rs
index 815f7526632..4625669d5ec 100644
--- a/src/test/compile-fail/ref-suggestion.rs
+++ b/src/test/compile-fail/ref-suggestion.rs
@@ -14,12 +14,14 @@ fn main() {
     //~^ HELP use a `ref` binding as shown
     //~| SUGGESTION let ref y = x;
     x; //~ ERROR use of moved value
+    //~^ HELP run `rustc --explain E0382` to see a detailed explanation
 
     let x = vec![1];
     let mut y = x;
     //~^ HELP use a `ref` binding as shown
     //~| SUGGESTION let ref mut y = x;
     x; //~ ERROR use of moved value
+    //~^ HELP run `rustc --explain E0382` to see a detailed explanation
 
     let x = (Some(vec![1]), ());
 
@@ -30,4 +32,5 @@ fn main() {
         _ => {},
     }
     x; //~ ERROR use of partially moved value
+    //~^ HELP run `rustc --explain E0382` to see a detailed explanation
 }
diff --git a/src/test/compile-fail/suggest-path-instead-of-mod-dot-item.rs b/src/test/compile-fail/suggest-path-instead-of-mod-dot-item.rs
index 1d04679fd11..8877377a6ec 100644
--- a/src/test/compile-fail/suggest-path-instead-of-mod-dot-item.rs
+++ b/src/test/compile-fail/suggest-path-instead-of-mod-dot-item.rs
@@ -27,46 +27,54 @@ fn h1() -> i32 {
     a.I
         //~^ ERROR E0425
         //~| HELP To reference an item from the `a` module, use `a::I`
+        //~| HELP run `rustc --explain E0425` to see a detailed explanation
 }
 
 fn h2() -> i32 {
     a.g()
         //~^ ERROR E0425
         //~| HELP To call a function from the `a` module, use `a::g(..)`
+        //~| HELP run `rustc --explain E0425` to see a detailed explanation
 }
 
 fn h3() -> i32 {
     a.b.J
         //~^ ERROR E0425
         //~| HELP To reference an item from the `a` module, use `a::b`
+        //~| HELP run `rustc --explain E0425` to see a detailed explanation
 }
 
 fn h4() -> i32 {
     a::b.J
         //~^ ERROR E0425
         //~| HELP To reference an item from the `a::b` module, use `a::b::J`
+        //~| HELP run `rustc --explain E0425` to see a detailed explanation
 }
 
 fn h5() -> i32 {
     a.b.f()
         //~^ ERROR E0425
         //~| HELP To reference an item from the `a` module, use `a::b`
+        //~| HELP run `rustc --explain E0425` to see a detailed explanation
 }
 
 fn h6() -> i32 {
     a::b.f()
         //~^ ERROR E0425
         //~| HELP To call a function from the `a::b` module, use `a::b::f(..)`
+        //~| HELP run `rustc --explain E0425` to see a detailed explanation
 }
 
 fn h7() {
     a::b
         //~^ ERROR E0425
         //~| HELP Module `a::b` cannot be the value of an expression
+        //~| HELP run `rustc --explain E0425` to see a detailed explanation
 }
 
 fn h8() -> i32 {
     a::b()
         //~^ ERROR E0425
         //~| HELP No function corresponds to `a::b(..)`
+        //~| HELP run `rustc --explain E0425` to see a detailed explanation
 }
diff --git a/src/test/compile-fail/suggest-private-fields.rs b/src/test/compile-fail/suggest-private-fields.rs
index 8bc8a7a60bd..9c61f618e69 100644
--- a/src/test/compile-fail/suggest-private-fields.rs
+++ b/src/test/compile-fail/suggest-private-fields.rs
@@ -25,6 +25,7 @@ fn main () {
         aa: 20, //~ ERROR structure `xc::B` has no field named `aa`
         //~^ HELP did you mean `a`?
         bb: 20, //~ ERROR structure `xc::B` has no field named `bb`
+        //~^ HELP did you mean `a`?
     };
     // local crate struct
     let l = A {
diff --git a/src/test/compile-fail/trait-object-reference-without-parens-suggestion.rs b/src/test/compile-fail/trait-object-reference-without-parens-suggestion.rs
index fc2ed83b272..29360e58b5b 100644
--- a/src/test/compile-fail/trait-object-reference-without-parens-suggestion.rs
+++ b/src/test/compile-fail/trait-object-reference-without-parens-suggestion.rs
@@ -13,8 +13,10 @@ fn main() {
     //~^ ERROR expected a path
     //~| HELP try adding parentheses
     //~| SUGGESTION let _: &(Copy + 'static);
+    //~| HELP run `rustc --explain E0178` to see a detailed explanation
     let _: &'static Copy + 'static;
     //~^ ERROR expected a path
     //~| HELP try adding parentheses
     //~| SUGGESTION let _: &'static (Copy + 'static);
+    //~| HELP run `rustc --explain E0178` to see a detailed explanation
 }
diff --git a/src/test/compile-fail/use-mod.rs b/src/test/compile-fail/use-mod.rs
index 9cc3c92e2e3..bbb063770c1 100644
--- a/src/test/compile-fail/use-mod.rs
+++ b/src/test/compile-fail/use-mod.rs
@@ -11,6 +11,7 @@
 use foo::bar::{
     self,
 //~^ ERROR `self` import can only appear once in the list
+//~^^ NOTE previous import of `bar` here
     Bar,
     self
 //~^ NOTE another `self` import appears here
diff --git a/src/test/compile-fail/variance-unused-type-param.rs b/src/test/compile-fail/variance-unused-type-param.rs
index 862d842d62c..f7fed32cb5a 100644
--- a/src/test/compile-fail/variance-unused-type-param.rs
+++ b/src/test/compile-fail/variance-unused-type-param.rs
@@ -16,15 +16,18 @@
 struct SomeStruct<A> { x: u32 }
 //~^ ERROR parameter `A` is never used
 //~| HELP PhantomData
+//~| HELP run `rustc --explain E0392` to see a detailed explanation
 
 enum SomeEnum<A> { Nothing }
 //~^ ERROR parameter `A` is never used
 //~| HELP PhantomData
+//~| HELP run `rustc --explain E0392` to see a detailed explanation
 
 // Here T might *appear* used, but in fact it isn't.
 enum ListCell<T> {
 //~^ ERROR parameter `T` is never used
 //~| HELP PhantomData
+//~| HELP run `rustc --explain E0392` to see a detailed explanation
     Cons(Box<ListCell<T>>),
     Nil
 }