Rollup merge of #47613 - estebank:rustc_on_unimplemented, r=nikomatsakis

Add filtering options to `rustc_on_unimplemented`

- Add filtering options to `rustc_on_unimplemented` for local traits, filtering on `Self` and type arguments.
- Add a way to provide custom notes.
- Tweak binops text.
- Add filter to detect wether `Self` is local or belongs to another crate.
- Add filter to `Iterator` diagnostic for `&str`.

Partly addresses #44755 with a different syntax, as a first approach. Fixes #46216, fixes #37522, CC #34297, #46806.

10 files changed, 97 insertions, 18 deletions

diff --git a/src/test/ui/impl-trait/equality.rs b/src/test/ui/impl-trait/equality.rs
index 36df4f0eb4d..9d9d4cef311 100644
--- a/src/test/ui/impl-trait/equality.rs
+++ b/src/test/ui/impl-trait/equality.rs
@@ -32,7 +32,7 @@ fn sum_to(n: u32) -> impl Foo {
         0
     } else {
         n + sum_to(n - 1)
-        //~^ ERROR the trait bound `u32: std::ops::Add<impl Foo>` is not satisfied
+        //~^ ERROR cannot add `impl Foo` to `u32`
     }
 }
 
diff --git a/src/test/ui/impl-trait/equality.stderr b/src/test/ui/impl-trait/equality.stderr
index 3fc08a0900f..8ec81903803 100644
--- a/src/test/ui/impl-trait/equality.stderr
+++ b/src/test/ui/impl-trait/equality.stderr
@@ -7,7 +7,7 @@ error[E0308]: mismatched types
    = note: expected type `i32`
               found type `u32`
 
-error[E0277]: the trait bound `u32: std::ops::Add<impl Foo>` is not satisfied
+error[E0277]: cannot add `impl Foo` to `u32`
   --> $DIR/equality.rs:34:11
    |
 34 |         n + sum_to(n - 1)
diff --git a/src/test/ui/mismatched_types/binops.rs b/src/test/ui/mismatched_types/binops.rs
index e45616cd67a..5144b59955c 100644
--- a/src/test/ui/mismatched_types/binops.rs
+++ b/src/test/ui/mismatched_types/binops.rs
@@ -9,10 +9,10 @@
 // except according to those terms.
 
 fn main() {
-    1 + Some(1); //~ ERROR is not satisfied
-    2 as usize - Some(1); //~ ERROR is not satisfied
-    3 * (); //~ ERROR is not satisfied
-    4 / ""; //~ ERROR is not satisfied
+    1 + Some(1); //~ ERROR cannot add `std::option::Option<{integer}>` to `{integer}`
+    2 as usize - Some(1); //~ ERROR cannot substract `std::option::Option<{integer}>` from `usize`
+    3 * (); //~ ERROR cannot multiply `()` to `{integer}`
+    4 / ""; //~ ERROR cannot divide `{integer}` by `&str`
     5 < String::new(); //~ ERROR is not satisfied
     6 == Ok(1); //~ ERROR is not satisfied
 }
diff --git a/src/test/ui/mismatched_types/binops.stderr b/src/test/ui/mismatched_types/binops.stderr
index 8541ad52e01..1b7fba05063 100644
--- a/src/test/ui/mismatched_types/binops.stderr
+++ b/src/test/ui/mismatched_types/binops.stderr
@@ -1,31 +1,31 @@
-error[E0277]: the trait bound `{integer}: std::ops::Add<std::option::Option<{integer}>>` is not satisfied
+error[E0277]: cannot add `std::option::Option<{integer}>` to `{integer}`
   --> $DIR/binops.rs:12:7
    |
-12 |     1 + Some(1); //~ ERROR is not satisfied
+12 |     1 + Some(1); //~ ERROR cannot add `std::option::Option<{integer}>` to `{integer}`
    |       ^ no implementation for `{integer} + std::option::Option<{integer}>`
    |
    = help: the trait `std::ops::Add<std::option::Option<{integer}>>` is not implemented for `{integer}`
 
-error[E0277]: the trait bound `usize: std::ops::Sub<std::option::Option<{integer}>>` is not satisfied
+error[E0277]: cannot substract `std::option::Option<{integer}>` from `usize`
   --> $DIR/binops.rs:13:16
    |
-13 |     2 as usize - Some(1); //~ ERROR is not satisfied
+13 |     2 as usize - Some(1); //~ ERROR cannot substract `std::option::Option<{integer}>` from `usize`
    |                ^ no implementation for `usize - std::option::Option<{integer}>`
    |
    = help: the trait `std::ops::Sub<std::option::Option<{integer}>>` is not implemented for `usize`
 
-error[E0277]: the trait bound `{integer}: std::ops::Mul<()>` is not satisfied
+error[E0277]: cannot multiply `()` to `{integer}`
   --> $DIR/binops.rs:14:7
    |
-14 |     3 * (); //~ ERROR is not satisfied
+14 |     3 * (); //~ ERROR cannot multiply `()` to `{integer}`
    |       ^ no implementation for `{integer} * ()`
    |
    = help: the trait `std::ops::Mul<()>` is not implemented for `{integer}`
 
-error[E0277]: the trait bound `{integer}: std::ops::Div<&str>` is not satisfied
+error[E0277]: cannot divide `{integer}` by `&str`
   --> $DIR/binops.rs:15:7
    |
-15 |     4 / ""; //~ ERROR is not satisfied
+15 |     4 / ""; //~ ERROR cannot divide `{integer}` by `&str`
    |       ^ no implementation for `{integer} / &str`
    |
    = help: the trait `std::ops::Div<&str>` is not implemented for `{integer}`
diff --git a/src/test/ui/on-unimplemented/auxiliary/no_debug.rs b/src/test/ui/on-unimplemented/auxiliary/no_debug.rs
new file mode 100644
index 00000000000..0f833c62637
--- /dev/null
+++ b/src/test/ui/on-unimplemented/auxiliary/no_debug.rs
@@ -0,0 +1,14 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+// ignore-tidy-linelength
+
+#![crate_type = "lib"]
+
+pub struct Bar;
diff --git a/src/test/ui/on-unimplemented/no-debug.rs b/src/test/ui/on-unimplemented/no-debug.rs
new file mode 100644
index 00000000000..fff6122c6b3
--- /dev/null
+++ b/src/test/ui/on-unimplemented/no-debug.rs
@@ -0,0 +1,27 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// aux-build:no_debug.rs
+
+extern crate no_debug;
+
+use no_debug::Bar;
+
+struct Foo;
+
+fn main() {
+    println!("{:?} {:?}", Foo, Bar);
+    println!("{} {}", Foo, Bar);
+}
+//~^^^ ERROR `Foo` doesn't implement `std::fmt::Debug`
+//~| ERROR `no_debug::Bar` doesn't implement `std::fmt::Debug`
+//~^^^^ ERROR `Foo` doesn't implement `std::fmt::Display`
+//~| ERROR `no_debug::Bar` doesn't implement `std::fmt::Display`
+
diff --git a/src/test/ui/on-unimplemented/no-debug.stderr b/src/test/ui/on-unimplemented/no-debug.stderr
new file mode 100644
index 00000000000..af5b1e91211
--- /dev/null
+++ b/src/test/ui/on-unimplemented/no-debug.stderr
@@ -0,0 +1,38 @@
+error[E0277]: `Foo` doesn't implement `std::fmt::Debug`
+  --> $DIR/no-debug.rs:20:27
+   |
+20 |     println!("{:?} {:?}", Foo, Bar);
+   |                           ^^^ `Foo` cannot be formatted using `:?`; add `#[derive(Debug)]` or manually implement `std::fmt::Debug`
+   |
+   = help: the trait `std::fmt::Debug` is not implemented for `Foo`
+   = note: required by `std::fmt::Debug::fmt`
+
+error[E0277]: `no_debug::Bar` doesn't implement `std::fmt::Debug`
+  --> $DIR/no-debug.rs:20:32
+   |
+20 |     println!("{:?} {:?}", Foo, Bar);
+   |                                ^^^ `no_debug::Bar` cannot be formatted using `:?` because it doesn't implement `std::fmt::Debug`
+   |
+   = help: the trait `std::fmt::Debug` is not implemented for `no_debug::Bar`
+   = note: required by `std::fmt::Debug::fmt`
+
+error[E0277]: `Foo` doesn't implement `std::fmt::Display`
+  --> $DIR/no-debug.rs:21:23
+   |
+21 |     println!("{} {}", Foo, Bar);
+   |                       ^^^ `Foo` cannot be formatted with the default formatter; try using `:?` instead if you are using a format string
+   |
+   = help: the trait `std::fmt::Display` is not implemented for `Foo`
+   = note: required by `std::fmt::Display::fmt`
+
+error[E0277]: `no_debug::Bar` doesn't implement `std::fmt::Display`
+  --> $DIR/no-debug.rs:21:28
+   |
+21 |     println!("{} {}", Foo, Bar);
+   |                            ^^^ `no_debug::Bar` cannot be formatted with the default formatter; try using `:?` instead if you are using a format string
+   |
+   = help: the trait `std::fmt::Display` is not implemented for `no_debug::Bar`
+   = note: required by `std::fmt::Display::fmt`
+
+error: aborting due to 4 previous errors
+
diff --git a/src/test/ui/span/multiline-span-simple.rs b/src/test/ui/span/multiline-span-simple.rs
index f8e4cbcbf19..dd09534480e 100644
--- a/src/test/ui/span/multiline-span-simple.rs
+++ b/src/test/ui/span/multiline-span-simple.rs
@@ -20,7 +20,7 @@ fn main() {
     let x = 1;
     let y = 2;
     let z = 3;
-    foo(1 as u32 + //~ ERROR not satisfied
+    foo(1 as u32 + //~ ERROR cannot add `()` to `u32`
 
         bar(x,
 
diff --git a/src/test/ui/span/multiline-span-simple.stderr b/src/test/ui/span/multiline-span-simple.stderr
index b068798630e..a18dfeb31d9 100644
--- a/src/test/ui/span/multiline-span-simple.stderr
+++ b/src/test/ui/span/multiline-span-simple.stderr
@@ -1,7 +1,7 @@
-error[E0277]: the trait bound `u32: std::ops::Add<()>` is not satisfied
+error[E0277]: cannot add `()` to `u32`
   --> $DIR/multiline-span-simple.rs:23:18
    |
-23 |     foo(1 as u32 + //~ ERROR not satisfied
+23 |     foo(1 as u32 + //~ ERROR cannot add `()` to `u32`
    |                  ^ no implementation for `u32 + ()`
    |
    = help: the trait `std::ops::Add<()>` is not implemented for `u32`
diff --git a/src/test/ui/suggestions/for-c-in-str.stderr b/src/test/ui/suggestions/for-c-in-str.stderr
index 7a6dc9a5040..88a7b1b49d6 100644
--- a/src/test/ui/suggestions/for-c-in-str.stderr
+++ b/src/test/ui/suggestions/for-c-in-str.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `&str: std::iter::Iterator` is not satisfied
   --> $DIR/for-c-in-str.rs:14:14
    |
 14 |     for c in "asdf" {
-   |              ^^^^^^ `&str` is not an iterator; maybe try calling `.iter()` or a similar method
+   |              ^^^^^^ `&str` is not an iterator; try calling `.chars()` or `.bytes()`
    |
    = help: the trait `std::iter::Iterator` is not implemented for `&str`
    = note: required by `std::iter::IntoIterator::into_iter`