Add three point error handling to borrowck

Closes #45988

src/test/ui/nll/capture-ref-in-struct.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// compile-flags:-Znll -Zborrowck=mir
+// compile-flags:-Znll -Zborrowck=mir -Znll-dump-cause
 
 // Test that a structure which tries to store a pointer to `y` into
 // `p` (indirectly) fails to compile.

src/test/ui/nll/capture-ref-in-struct.stderr

@@ -6,6 +6,9 @@ error[E0597]: `y` does not live long enough
 ...
 37 |     }
    |      - borrowed value only lives until here
+38 | 
+39 |     deref(p);
+   |           - borrow later used here
    |
    = note: borrowed value must be valid for lifetime '_#5r...
 

src/test/ui/nll/closure-requirements/escape-argument.rs

@@ -22,7 +22,7 @@
 // basically checking that the MIR type checker correctly enforces the
 // closure signature.
 
-// compile-flags:-Znll -Zborrowck=mir -Zverbose
+// compile-flags:-Znll -Zborrowck=mir -Znll-dump-cause -Zverbose
 
 #![feature(rustc_attrs)]
 

src/test/ui/nll/closure-requirements/escape-argument.stderr

@@ -31,6 +31,9 @@ error[E0597]: `y` does not live long enough
 38 |         //~^ ERROR `y` does not live long enough [E0597]
 39 |     }
    |      - borrowed value only lives until here
+40 | 
+41 |     deref(p);
+   |           - borrow later used here
    |
    = note: borrowed value must be valid for lifetime '_#6r...
 

src/test/ui/nll/closure-requirements/escape-upvar-nested.rs

@@ -15,7 +15,7 @@
 //
 // except that the closure does so via a second closure.
 
-// compile-flags:-Znll -Zborrowck=mir -Zverbose
+// compile-flags:-Znll -Zborrowck=mir -Znll-dump-cause -Zverbose
 
 #![feature(rustc_attrs)]
 

src/test/ui/nll/closure-requirements/escape-upvar-nested.stderr

@@ -58,6 +58,9 @@ error[E0597]: `y` does not live long enough
 ...
 36 |       }
    |        - borrowed value only lives until here
+37 | 
+38 |       deref(p);
+   |             - borrow later used here
    |
    = note: borrowed value must be valid for lifetime '_#4r...
 

src/test/ui/nll/closure-requirements/escape-upvar-ref.rs

@@ -19,7 +19,7 @@
 // `'b`.  This relationship is propagated to the closure creator,
 // which reports an error.
 
-// compile-flags:-Znll -Zborrowck=mir -Zverbose
+// compile-flags:-Znll -Zborrowck=mir -Znll-dump-cause -Zverbose
 
 #![feature(rustc_attrs)]
 

src/test/ui/nll/closure-requirements/escape-upvar-ref.stderr

@@ -35,6 +35,9 @@ error[E0597]: `y` does not live long enough
 ...
 36 |     }
    |      - borrowed value only lives until here
+37 | 
+38 |     deref(p);
+   |           - borrow later used here
    |
    = note: borrowed value must be valid for lifetime '_#4r...
 

src/test/ui/nll/get_default.rs

@@ -13,7 +13,7 @@
 // a variety of errors from the older, AST-based machinery (notably
 // borrowck), and then we get the NLL error at the end.
 
-// compile-flags:-Znll -Zborrowck=compare
+// compile-flags:-Znll -Zborrowck=compare -Znll-dump-cause
 
 struct Map {
 }

src/test/ui/nll/get_default.stderr

@@ -42,6 +42,9 @@ error[E0502]: cannot borrow `*map` as mutable because it is also borrowed as imm
 43 |             Some(v) => {
 44 |                 map.set(String::new()); // Both AST and MIR error here
    |                 ^^^ mutable borrow occurs here
+...
+47 |                 return v;
+   |                        - borrow later used here
 
 error: aborting due to 4 previous errors
 

src/test/ui/nll/maybe-initialized-drop-implicit-fragment-drop.rs

@@ -8,7 +8,8 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-//compile-flags: -Z emit-end-regions -Zborrowck=mir -Z nll
+//compile-flags: -Z emit-end-regions -Zborrowck=mir -Z nll -Znll-dump-cause
+
 
 #![allow(warnings)]
 

src/test/ui/nll/maybe-initialized-drop-implicit-fragment-drop.stderr

@@ -6,6 +6,9 @@ error[E0506]: cannot assign to `x` because it is borrowed
 ...
 31 |     x = 1; //~ ERROR cannot assign to `x` because it is borrowed [E0506]
    |     ^^^^^ assignment to borrowed `x` occurs here
+32 |     // FIXME ^ Should not error in the future with implicit dtors, only manually implemented ones
+33 | }
+   |  - borrow later used here, when `foo` is dropped
 
 error: aborting due to previous error
 

src/test/ui/nll/maybe-initialized-drop-with-fragment.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-//compile-flags: -Z emit-end-regions -Zborrowck=mir -Z nll
+//compile-flags: -Z emit-end-regions -Zborrowck=mir -Znll -Znll-dump-cause
 
 #![allow(warnings)]
 

src/test/ui/nll/maybe-initialized-drop-with-fragment.stderr

@@ -6,6 +6,8 @@ error[E0506]: cannot assign to `x` because it is borrowed
 ...
 31 |     x = 1; //~ ERROR cannot assign to `x` because it is borrowed [E0506]
    |     ^^^^^ assignment to borrowed `x` occurs here
+32 | }
+   |  - borrow later used here, when `foo` is dropped
 
 error: aborting due to previous error
 

src/test/ui/nll/maybe-initialized-drop-with-uninitialized-fragments.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-//compile-flags: -Z emit-end-regions -Zborrowck=mir -Z nll
+//compile-flags: -Z emit-end-regions -Zborrowck=mir -Znll -Znll-dump-cause
 
 #![allow(warnings)]
 

src/test/ui/nll/maybe-initialized-drop-with-uninitialized-fragments.stderr

@@ -6,6 +6,9 @@ error[E0506]: cannot assign to `x` because it is borrowed
 ...
 32 |     x = 1; //~ ERROR cannot assign to `x` because it is borrowed [E0506]
    |     ^^^^^ assignment to borrowed `x` occurs here
+33 |     // FIXME ^ This currently errors and it should not.
+34 | }
+   |  - borrow later used here, when `foo` is dropped
 
 error: aborting due to previous error
 

src/test/ui/nll/maybe-initialized-drop.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-//compile-flags: -Z emit-end-regions -Zborrowck=mir -Z nll
+//compile-flags: -Z emit-end-regions -Zborrowck=mir -Znll -Znll-dump-cause
 
 #![allow(warnings)]
 

src/test/ui/nll/maybe-initialized-drop.stderr

@@ -5,6 +5,8 @@ error[E0506]: cannot assign to `x` because it is borrowed
    |                          ------ borrow of `x` occurs here
 26 |     x = 1; //~ ERROR cannot assign to `x` because it is borrowed [E0506]
    |     ^^^^^ assignment to borrowed `x` occurs here
+27 | }
+   |  - borrow later used here, when `wrap` is dropped
 
 error: aborting due to previous error