Detect long types in E0308 and write them to disk

On type error with long types, print an abridged type and write the full
type to disk.

Print the widest possible short type while still fitting in the
terminal.

10 files changed, 182 insertions, 12 deletions

diff --git a/src/test/ui/diagnostic-width/long-E0308.rs b/src/test/ui/diagnostic-width/long-E0308.rs
new file mode 100644
index 00000000000..22ee1cd8d55
--- /dev/null
+++ b/src/test/ui/diagnostic-width/long-E0308.rs
@@ -0,0 +1,86 @@
+// compile-flags: --diagnostic-width=100
+// normalize-stderr-test: "long-type-\d+" -> "long-type-hash"
+
+struct Atype<T, K>(T, K);
+struct Btype<T, K>(T, K);
+struct Ctype<T, K>(T, K);
+
+fn main() {
+    let x: Atype<
+      Btype<
+        Ctype<
+          Atype<
+            Btype<
+              Ctype<
+                Atype<
+                  Btype<
+                    Ctype<i32, i32>,
+                    i32
+                  >,
+                  i32
+                >,
+                i32
+              >,
+              i32
+            >,
+            i32
+          >,
+          i32
+        >,
+        i32
+      >,
+      i32
+    > = Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(
+        Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(
+            Ok("")
+        ))))))))))))))))))))))))))))))
+    ))))))))))))))))))))))))))))));
+    //~^^^^^ ERROR E0308
+
+    let _ = Some(Ok(Some(Some(Some(Some(Some(Some(Some(Some(Some(Some(Some(Some(Some(Some(Some(
+        Some(Some(Some(Some(Some(Some(Some(Some(Some(Some(Some(Some(Some(Some(Some(Some(Some(Some(
+            Some(Some(Some(Some(Some(Some(Some(Some(Some(Some(Some(Some(Some(Some(Some(Some(Some(
+                Some(Some(Some(Some(Some(Some(Some(Some(Some("")))))))))
+            )))))))))))))))))
+        ))))))))))))))))))
+    ))))))))))))))))) == Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(
+        Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(
+            Ok(Ok(Ok(Ok(Ok(Ok(Ok("")))))))
+        ))))))))))))))))))))))))))))))
+    ))))))))))))))))))))))));
+    //~^^^^^ ERROR E0308
+
+    let x: Atype<
+      Btype<
+        Ctype<
+          Atype<
+            Btype<
+              Ctype<
+                Atype<
+                  Btype<
+                    Ctype<i32, i32>,
+                    i32
+                  >,
+                  i32
+                >,
+                i32
+              >,
+              i32
+            >,
+            i32
+          >,
+          i32
+        >,
+        i32
+      >,
+      i32
+    > = ();
+    //~^ ERROR E0308
+
+    let _: () = Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(
+        Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(
+            Ok(Ok(Ok(Ok(Ok(Ok(Ok("")))))))
+        ))))))))))))))))))))))))))))))
+    ))))))))))))))))))))))));
+    //~^^^^^ ERROR E0308
+}
diff --git a/src/test/ui/diagnostic-width/long-E0308.stderr b/src/test/ui/diagnostic-width/long-E0308.stderr
new file mode 100644
index 00000000000..142e34f7687
--- /dev/null
+++ b/src/test/ui/diagnostic-width/long-E0308.stderr
@@ -0,0 +1,80 @@
+error[E0308]: mismatched types
+  --> $DIR/long-E0308.rs:33:9
+   |
+LL |        let x: Atype<
+   |   ____________-
+LL |  |       Btype<
+LL |  |         Ctype<
+LL |  |           Atype<
+...   |
+LL |  |       i32
+LL |  |     > = Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(...
+   |  |_____-___^
+   | ||_____|
+   | |      expected due to this
+LL | |          Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(...
+LL | |              Ok("")
+LL | |          ))))))))))))))))))))))))))))))
+LL | |      ))))))))))))))))))))))))))))));
+   | |___________________________________^ expected struct `Atype`, found enum `Result`
+   |
+   = note: expected struct `Atype<Btype<Ctype<Atype<Btype<Ctype<..., ...>, ...>, ...>, ...>, ...>, ...>`
+           the full type name has been written to '$TEST_BUILD_DIR/diagnostic-width/long-E0308/long-E0308.long-type-hash.txt'
+                found enum `Result<Result<Result<Result<Result<..., ...>, ...>, ...>, ...>, ...>`
+           the full type name has been written to '$TEST_BUILD_DIR/diagnostic-width/long-E0308/long-E0308.long-type-hash.txt'
+
+error[E0308]: mismatched types
+  --> $DIR/long-E0308.rs:46:26
+   |
+LL |       ))))))))))))))))) == Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok...
+   |  __________________________^
+LL | |         Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(O...
+LL | |             Ok(Ok(Ok(Ok(Ok(Ok(Ok("")))))))
+LL | |         ))))))))))))))))))))))))))))))
+LL | |     ))))))))))))))))))))))));
+   | |____________________________^ expected enum `Option`, found enum `Result`
+   |
+   = note: expected enum `Option<Result<Option<Option<Option<Option<Option<Option<Option<...>>>>>>>, ...>>`
+           the full type name has been written to '$TEST_BUILD_DIR/diagnostic-width/long-E0308/long-E0308.long-type-hash.txt'
+              found enum `Result<Result<Result<Result<Result<..., ...>, ...>, ...>, ...>, ...>`
+           the full type name has been written to '$TEST_BUILD_DIR/diagnostic-width/long-E0308/long-E0308.long-type-hash.txt'
+
+error[E0308]: mismatched types
+  --> $DIR/long-E0308.rs:77:9
+   |
+LL |       let x: Atype<
+   |  ____________-
+LL | |       Btype<
+LL | |         Ctype<
+LL | |           Atype<
+...  |
+LL | |       i32
+LL | |     > = ();
+   | |     -   ^^ expected struct `Atype`, found `()`
+   | |_____|
+   |       expected due to this
+   |
+   = note: expected struct `Atype<Btype<Ctype<Atype<Btype<Ctype<..., ...>, ...>, ...>, ...>, ...>, ...>`
+           the full type name has been written to '$TEST_BUILD_DIR/diagnostic-width/long-E0308/long-E0308.long-type-hash.txt'
+           found unit type `()`
+
+error[E0308]: mismatched types
+  --> $DIR/long-E0308.rs:80:17
+   |
+LL |       let _: () = Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(
+   |  ____________--___^
+   | |            |
+   | |            expected due to this
+LL | |         Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(Ok(O...
+LL | |             Ok(Ok(Ok(Ok(Ok(Ok(Ok("")))))))
+LL | |         ))))))))))))))))))))))))))))))
+LL | |     ))))))))))))))))))))))));
+   | |____________________________^ expected `()`, found enum `Result`
+   |
+   = note: expected unit type `()`
+                   found enum `Result<Result<Result<Result<Result<..., ...>, ...>, ...>, ...>, ...>`
+           the full type name has been written to '$TEST_BUILD_DIR/diagnostic-width/long-E0308/long-E0308.long-type-hash.txt'
+
+error: aborting due to 4 previous errors
+
+For more information about this error, try `rustc --explain E0308`.
diff --git a/src/test/ui/error-codes/E0275.stderr b/src/test/ui/error-codes/E0275.stderr
index 49a4d984af9..8d4f44218bc 100644
--- a/src/test/ui/error-codes/E0275.stderr
+++ b/src/test/ui/error-codes/E0275.stderr
@@ -5,7 +5,7 @@ LL | impl<T> Foo for T where Bar<T>: Foo {}
    |                                 ^^^
    |
    = help: consider increasing the recursion limit by adding a `#![recursion_limit = "256"]` attribute to your crate (`E0275`)
-note: required for `Bar<Bar<Bar<Bar<Bar<Bar<...>>>>>>` to implement `Foo`
+note: required for `Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<Bar<...>>>>>>>>>>>>>>>>>>>>>>>` to implement `Foo`
   --> $DIR/E0275.rs:6:9
    |
 LL | impl<T> Foo for T where Bar<T>: Foo {}
diff --git a/src/test/ui/issues/issue-20413.stderr b/src/test/ui/issues/issue-20413.stderr
index 91509ceace8..0a5867429e2 100644
--- a/src/test/ui/issues/issue-20413.stderr
+++ b/src/test/ui/issues/issue-20413.stderr
@@ -14,7 +14,7 @@ LL | impl<T> Foo for T where NoData<T>: Foo {
    |                                    ^^^
    |
    = help: consider increasing the recursion limit by adding a `#![recursion_limit = "256"]` attribute to your crate (`issue_20413`)
-note: required for `NoData<NoData<NoData<NoData<NoData<NoData<...>>>>>>` to implement `Foo`
+note: required for `NoData<NoData<NoData<NoData<NoData<NoData<NoData<NoData<NoData<NoData<NoData<NoData<NoData<NoData<...>>>>>>>>>>>>>>` to implement `Foo`
   --> $DIR/issue-20413.rs:9:9
    |
 LL | impl<T> Foo for T where NoData<T>: Foo {
@@ -30,13 +30,13 @@ LL | impl<T> Bar for T where EvenLessData<T>: Baz {
    |                                          ^^^
    |
    = help: consider increasing the recursion limit by adding a `#![recursion_limit = "256"]` attribute to your crate (`issue_20413`)
-note: required for `AlmostNoData<EvenLessData<AlmostNoData<EvenLessData<AlmostNoData<EvenLessData<...>>>>>>` to implement `Bar`
+note: required for `AlmostNoData<EvenLessData<AlmostNoData<EvenLessData<AlmostNoData<EvenLessData<AlmostNoData<EvenLessData<...>>>>>>>>` to implement `Bar`
   --> $DIR/issue-20413.rs:28:9
    |
 LL | impl<T> Bar for T where EvenLessData<T>: Baz {
    |         ^^^     ^
    = note: the full type name has been written to '$TEST_BUILD_DIR/issues/issue-20413/issue-20413.long-type-hash.txt'
-note: required for `EvenLessData<AlmostNoData<EvenLessData<AlmostNoData<EvenLessData<AlmostNoData<...>>>>>>` to implement `Baz`
+note: required for `EvenLessData<AlmostNoData<EvenLessData<AlmostNoData<EvenLessData<AlmostNoData<EvenLessData<AlmostNoData<...>>>>>>>>` to implement `Baz`
   --> $DIR/issue-20413.rs:35:9
    |
 LL | impl<T> Baz for T where AlmostNoData<T>: Bar {
@@ -52,13 +52,13 @@ LL | impl<T> Baz for T where AlmostNoData<T>: Bar {
    |                                          ^^^
    |
    = help: consider increasing the recursion limit by adding a `#![recursion_limit = "256"]` attribute to your crate (`issue_20413`)
-note: required for `EvenLessData<AlmostNoData<EvenLessData<AlmostNoData<EvenLessData<AlmostNoData<...>>>>>>` to implement `Baz`
+note: required for `EvenLessData<AlmostNoData<EvenLessData<AlmostNoData<EvenLessData<AlmostNoData<EvenLessData<AlmostNoData<...>>>>>>>>` to implement `Baz`
   --> $DIR/issue-20413.rs:35:9
    |
 LL | impl<T> Baz for T where AlmostNoData<T>: Bar {
    |         ^^^     ^
    = note: the full type name has been written to '$TEST_BUILD_DIR/issues/issue-20413/issue-20413.long-type-hash.txt'
-note: required for `AlmostNoData<EvenLessData<AlmostNoData<EvenLessData<AlmostNoData<EvenLessData<...>>>>>>` to implement `Bar`
+note: required for `AlmostNoData<EvenLessData<AlmostNoData<EvenLessData<AlmostNoData<EvenLessData<AlmostNoData<EvenLessData<...>>>>>>>>` to implement `Bar`
   --> $DIR/issue-20413.rs:28:9
    |
 LL | impl<T> Bar for T where EvenLessData<T>: Baz {
diff --git a/src/test/ui/recursion/issue-83150.stderr b/src/test/ui/recursion/issue-83150.stderr
index 4d00a708313..fc43efff2ea 100644
--- a/src/test/ui/recursion/issue-83150.stderr
+++ b/src/test/ui/recursion/issue-83150.stderr
@@ -12,7 +12,7 @@ LL |     func(&mut iter.map(|x| x + 1))
 error[E0275]: overflow evaluating the requirement `Map<&mut Map<&mut Map<&mut Map<..., ...>, ...>, ...>, ...>: Iterator`
    |
    = help: consider increasing the recursion limit by adding a `#![recursion_limit = "256"]` attribute to your crate (`issue_83150`)
-   = note: required for `&mut Map<&mut Map<&mut Map<..., ...>, ...>, ...>` to implement `Iterator`
+   = note: required for `&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut Map<&mut ..., ...>, ...>, ...>, ...>, ...>, ...>, ...>` to implement `Iterator`
    = note: the full type name has been written to '$TEST_BUILD_DIR/recursion/issue-83150/issue-83150.long-type-hash.txt'
 
 error: aborting due to previous error; 1 warning emitted
diff --git a/src/test/ui/regions/issue-102374.rs b/src/test/ui/regions/issue-102374.rs
index e0a1164211a..fd71248d9cb 100644
--- a/src/test/ui/regions/issue-102374.rs
+++ b/src/test/ui/regions/issue-102374.rs
@@ -1,3 +1,4 @@
+// normalize-stderr-test: "long-type-\d+" -> "long-type-hash"
 use std::cell::Cell;
 
 #[rustfmt::skip]
diff --git a/src/test/ui/regions/issue-102374.stderr b/src/test/ui/regions/issue-102374.stderr
index 31b855c36be..157850693ab 100644
--- a/src/test/ui/regions/issue-102374.stderr
+++ b/src/test/ui/regions/issue-102374.stderr
@@ -1,5 +1,5 @@
 error[E0308]: mismatched types
-  --> $DIR/issue-102374.rs:16:5
+  --> $DIR/issue-102374.rs:17:5
    |
 LL | ) -> i32 {
    |      --- expected `i32` because of return type
@@ -7,7 +7,8 @@ LL |     f
    |     ^ expected `i32`, found fn pointer
    |
    = note:    expected type `i32`
-           found fn pointer `for<'z1, 'a, 'b, 'c, 'd, 'e, 'f, 'g, 'h, 'i, 'j, 'k, 'l, 'm, 'n, 'o, 'p, 'q, 'r, 's, 't, 'u, 'v, 'w, 'x, 'y, 'z, 'z0> fn(Cell<(&'z1 i32, &'a i32, &'b i32, &'c i32, &'d i32, &'e i32, &'f i32, &'g i32, &'h i32, &'i i32, &'j i32, &'k i32, &'l i32, &'m i32, &'n i32, &'o i32, &'p i32, &'q i32, &'r i32, &'s i32, &'t i32, &'u i32, &'v i32, &'w i32, &'x i32, &'y i32, &'z i32, &'z0 i32)>)`
+           found fn pointer `for<'z1, 'a, 'b, 'c, 'd, 'e, 'f, 'g, 'h, 'i, 'j, 'k, 'l, 'm, 'n, 'o, 'p, 'q, 'r, 's, 't, 'u, 'v, 'w, 'x, 'y, 'z, 'z0> fn(Cell<...>)`
+           the full type name has been written to '$TEST_BUILD_DIR/regions/issue-102374/issue-102374.long-type-hash.txt'
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/traits/issue-91949-hangs-on-recursion.stderr b/src/test/ui/traits/issue-91949-hangs-on-recursion.stderr
index a74d2524996..1f18c5daf66 100644
--- a/src/test/ui/traits/issue-91949-hangs-on-recursion.stderr
+++ b/src/test/ui/traits/issue-91949-hangs-on-recursion.stderr
@@ -17,7 +17,7 @@ error[E0275]: overflow evaluating the requirement `(): Sized`
    = help: consider increasing the recursion limit by adding a `#![recursion_limit = "512"]` attribute to your crate (`issue_91949_hangs_on_recursion`)
    = note: required for `std::iter::Empty<()>` to implement `Iterator`
    = note: 171 redundant requirements hidden
-   = note: required for `IteratorOfWrapped<(), Map<IteratorOfWrapped<(), Map<..., ...>>, ...>>` to implement `Iterator`
+   = note: required for `IteratorOfWrapped<(), Map<IteratorOfWrapped<(), Map<IteratorOfWrapped<(), Map<..., ...>>, ...>>, ...>>` to implement `Iterator`
    = note: the full type name has been written to '$TEST_BUILD_DIR/traits/issue-91949-hangs-on-recursion/issue-91949-hangs-on-recursion.long-type-hash.txt'
 
 error: aborting due to previous error; 1 warning emitted
diff --git a/src/test/ui/typeck/return_type_containing_closure.rs b/src/test/ui/typeck/return_type_containing_closure.rs
index 29624e08a2e..ea7b47a5a38 100644
--- a/src/test/ui/typeck/return_type_containing_closure.rs
+++ b/src/test/ui/typeck/return_type_containing_closure.rs
@@ -1,3 +1,4 @@
+// normalize-stderr-test: "long-type-\d+" -> "long-type-hash"
 #[allow(unused)]
 fn foo() { //~ HELP a return type might be missing here
     vec!['a'].iter().map(|c| c)
diff --git a/src/test/ui/typeck/return_type_containing_closure.stderr b/src/test/ui/typeck/return_type_containing_closure.stderr
index 101aee39559..d6c103de3dc 100644
--- a/src/test/ui/typeck/return_type_containing_closure.stderr
+++ b/src/test/ui/typeck/return_type_containing_closure.stderr
@@ -1,11 +1,12 @@
 error[E0308]: mismatched types
-  --> $DIR/return_type_containing_closure.rs:3:5
+  --> $DIR/return_type_containing_closure.rs:4:5
    |
 LL |     vec!['a'].iter().map(|c| c)
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `()`, found struct `Map`
    |
    = note: expected unit type `()`
-                 found struct `Map<std::slice::Iter<'_, char>, [closure@$DIR/return_type_containing_closure.rs:3:26: 3:29]>`
+                 found struct `Map<std::slice::Iter<'_, char>, ...>`
+           the full type name has been written to '$TEST_BUILD_DIR/typeck/return_type_containing_closure/return_type_containing_closure.long-type-hash.txt'
 help: consider using a semicolon here
    |
 LL |     vec!['a'].iter().map(|c| c);