Tweak non-char/numeric in range pattern diagnostic

src/librustc_typeck/check/pat.rs

@@ -380,9 +380,38 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 E0029,
                 "only char and numeric types are allowed in range patterns"
             );
-            err.span_label(span, "ranges require char or numeric types");
+            if !lhs_compat && !rhs_compat {
-            err.note(&format!("start type: {}", self.ty_to_string(lhs_ty)));
+                err.span_label(
-            err.note(&format!("end type: {}", self.ty_to_string(rhs_ty)));
+                    begin.span,
+                    &format!("this is of type `{}` but it should be `char` or numeric", lhs_ty)
+                );
+                err.span_label(
+                    end.span,
+                    &format!("this is of type `{}` but it should be `char` or numeric", rhs_ty)
+                );
+            } else if !lhs_compat {
+                err.span_label(
+                    begin.span,
+                    &format!("this is of type `{}` but it should be `char` or numeric", lhs_ty)
+                );
+                if !rhs_ty.references_error() {
+                    err.span_label(
+                        end.span,
+                        &format!("this is of type `{}`", rhs_ty)
+                    );
+                }
+            } else {
+                err.span_label(
+                    end.span,
+                    &format!("this is of type `{}` but it should be `char` or numeric", rhs_ty)
+                );
+                if !lhs_ty.references_error() {
+                    err.span_label(
+                        begin.span,
+                        &format!("this is of type `{}`", lhs_ty)
+                    );
+                }
+            }
             if self.tcx.sess.teach(&err.get_code().unwrap()) {
                 err.note(
                     "In a match expression, only numbers and characters can be matched \

src/test/ui/error-codes/E0029-teach.stderr

@@ -2,10 +2,11 @@ error[E0029]: only char and numeric types are allowed in range patterns
   --> $DIR/E0029-teach.rs:7:9
    |
 LL |         "hello" ..= "world" => {}
-   |         ^^^^^^^^^^^^^^^^^^^ ranges require char or numeric types
+   |         -------^^^^^-------
+   |         |           |
+   |         |           this is of type `&'static str` but it should be `char` or numeric
+   |         this is of type `&'static str` but it should be `char` or numeric
    |
-   = note: start type: &'static str
-   = note: end type: &'static str
    = note: In a match expression, only numbers and characters can be matched against a range. This is because the compiler checks that the range is non-empty at compile-time, and is unable to evaluate arbitrary comparison functions. If you want to capture values of an orderable type between two end-points, you can use a guard.
 
 error: aborting due to previous error

src/test/ui/error-codes/E0029.stderr

@@ -2,10 +2,10 @@ error[E0029]: only char and numeric types are allowed in range patterns
   --> $DIR/E0029.rs:5:9
    |
 LL |         "hello" ..= "world" => {}
-   |         ^^^^^^^^^^^^^^^^^^^ ranges require char or numeric types
+   |         -------^^^^^-------
-   |
+   |         |           |
-   = note: start type: &'static str
+   |         |           this is of type `&'static str` but it should be `char` or numeric
-   = note: end type: &'static str
+   |         this is of type `&'static str` but it should be `char` or numeric
 
 error: aborting due to previous error
 

src/test/ui/match/match-range-fail.rs

@@ -3,15 +3,16 @@ fn main() {
         "bar" ..= "foo" => { }
     };
     //~^^ ERROR only char and numeric types are allowed in range
-    //~| start type: &'static str
-    //~| end type: &'static str
 
     match "wow" {
         10 ..= "what" => ()
     };
     //~^^ ERROR only char and numeric types are allowed in range
-    //~| start type: {integer}
+
-    //~| end type: &'static str
+    match "wow" {
+        true ..= "what" => {}
+    };
+    //~^^ ERROR only char and numeric types are allowed in range
 
     match 5 {
         'c' ..= 100 => { }

src/test/ui/match/match-range-fail.stderr

@@ -2,22 +2,30 @@ error[E0029]: only char and numeric types are allowed in range patterns
   --> $DIR/match-range-fail.rs:3:9
    |
 LL |         "bar" ..= "foo" => { }
-   |         ^^^^^^^^^^^^^^^ ranges require char or numeric types
+   |         -----^^^^^-----
-   |
+   |         |         |
-   = note: start type: &'static str
+   |         |         this is of type `&'static str` but it should be `char` or numeric
-   = note: end type: &'static str
+   |         this is of type `&'static str` but it should be `char` or numeric
 
 error[E0029]: only char and numeric types are allowed in range patterns
-  --> $DIR/match-range-fail.rs:10:16
+  --> $DIR/match-range-fail.rs:8:16
    |
 LL |         10 ..= "what" => ()
-   |                ^^^^^^ ranges require char or numeric types
+   |         --     ^^^^^^ this is of type `&'static str` but it should be `char` or numeric
+   |         |
+   |         this is of type `{integer}`
+
+error[E0029]: only char and numeric types are allowed in range patterns
+  --> $DIR/match-range-fail.rs:13:9
    |
-   = note: start type: {integer}
+LL |         true ..= "what" => {}
-   = note: end type: &'static str
+   |         ----^^^^^------
+   |         |        |
+   |         |        this is of type `&'static str` but it should be `char` or numeric
+   |         this is of type `bool` but it should be `char` or numeric
 
 error[E0308]: mismatched types
-  --> $DIR/match-range-fail.rs:17:9
+  --> $DIR/match-range-fail.rs:18:9
    |
 LL |         'c' ..= 100 => { }
    |         ^^^^^^^^^^^ expected integer, found char
@@ -25,7 +33,7 @@ LL |         'c' ..= 100 => { }
    = note: expected type `{integer}`
               found type `char`
 
-error: aborting due to 3 previous errors
+error: aborting due to 4 previous errors
 
 Some errors have detailed explanations: E0029, E0308.
 For more information about an error, try `rustc --explain E0029`.

src/test/ui/parser/recover-range-pats.stderr

@@ -401,19 +401,17 @@ error[E0029]: only char and numeric types are allowed in range patterns
   --> $DIR/recover-range-pats.rs:19:12
    |
 LL |     if let true..Y = 0 {}
-   |            ^^^^ ranges require char or numeric types
+   |            ^^^^  - this is of type `u8`
-   |
+   |            |
-   = note: start type: bool
+   |            this is of type `bool` but it should be `char` or numeric
-   = note: end type: u8
 
 error[E0029]: only char and numeric types are allowed in range patterns
   --> $DIR/recover-range-pats.rs:20:15
    |
 LL |     if let X..true = 0 {}
-   |               ^^^^ ranges require char or numeric types
+   |            -  ^^^^ this is of type `bool` but it should be `char` or numeric
-   |
+   |            |
-   = note: start type: u8
+   |            this is of type `u8`
-   = note: end type: bool
 
 error[E0308]: mismatched types
   --> $DIR/recover-range-pats.rs:21:12
@@ -437,19 +435,17 @@ error[E0029]: only char and numeric types are allowed in range patterns
   --> $DIR/recover-range-pats.rs:32:12
    |
 LL |     if let true..=Y = 0 {}
-   |            ^^^^ ranges require char or numeric types
+   |            ^^^^   - this is of type `u8`
-   |
+   |            |
-   = note: start type: bool
+   |            this is of type `bool` but it should be `char` or numeric
-   = note: end type: u8
 
 error[E0029]: only char and numeric types are allowed in range patterns
   --> $DIR/recover-range-pats.rs:33:16
    |
 LL |     if let X..=true = 0 {}
-   |                ^^^^ ranges require char or numeric types
+   |            -   ^^^^ this is of type `bool` but it should be `char` or numeric
-   |
+   |            |
-   = note: start type: u8
+   |            this is of type `u8`
-   = note: end type: bool
 
 error[E0308]: mismatched types
   --> $DIR/recover-range-pats.rs:34:12
@@ -473,19 +469,17 @@ error[E0029]: only char and numeric types are allowed in range patterns
   --> $DIR/recover-range-pats.rs:45:12
    |
 LL |     if let true...Y = 0 {}
-   |            ^^^^ ranges require char or numeric types
+   |            ^^^^   - this is of type `u8`
-   |
+   |            |
-   = note: start type: bool
+   |            this is of type `bool` but it should be `char` or numeric
-   = note: end type: u8
 
 error[E0029]: only char and numeric types are allowed in range patterns
   --> $DIR/recover-range-pats.rs:47:16
    |
 LL |     if let X...true = 0 {}
-   |                ^^^^ ranges require char or numeric types
+   |            -   ^^^^ this is of type `bool` but it should be `char` or numeric
-   |
+   |            |
-   = note: start type: u8
+   |            this is of type `u8`
-   = note: end type: bool
 
 error[E0308]: mismatched types
   --> $DIR/recover-range-pats.rs:49:12
@@ -509,10 +503,7 @@ error[E0029]: only char and numeric types are allowed in range patterns
   --> $DIR/recover-range-pats.rs:60:12
    |
 LL |     if let true.. = 0 {}
-   |            ^^^^ ranges require char or numeric types
+   |            ^^^^ this is of type `bool` but it should be `char` or numeric
-   |
-   = note: start type: bool
-   = note: end type: [type error]
 
 error[E0308]: mismatched types
   --> $DIR/recover-range-pats.rs:62:12
@@ -527,10 +518,7 @@ error[E0029]: only char and numeric types are allowed in range patterns
   --> $DIR/recover-range-pats.rs:70:12
    |
 LL |     if let true..= = 0 {}
-   |            ^^^^ ranges require char or numeric types
+   |            ^^^^ this is of type `bool` but it should be `char` or numeric
-   |
-   = note: start type: bool
-   = note: end type: [type error]
 
 error[E0308]: mismatched types
   --> $DIR/recover-range-pats.rs:72:12
@@ -545,10 +533,7 @@ error[E0029]: only char and numeric types are allowed in range patterns
   --> $DIR/recover-range-pats.rs:82:12
    |
 LL |     if let true... = 0 {}
-   |            ^^^^ ranges require char or numeric types
+   |            ^^^^ this is of type `bool` but it should be `char` or numeric
-   |
-   = note: start type: bool
-   = note: end type: [type error]
 
 error[E0308]: mismatched types
   --> $DIR/recover-range-pats.rs:85:12
@@ -563,10 +548,7 @@ error[E0029]: only char and numeric types are allowed in range patterns
   --> $DIR/recover-range-pats.rs:94:14
    |
 LL |     if let ..true = 0 {}
-   |              ^^^^ ranges require char or numeric types
+   |              ^^^^ this is of type `bool` but it should be `char` or numeric
-   |
-   = note: start type: [type error]
-   = note: end type: bool
 
 error[E0308]: mismatched types
   --> $DIR/recover-range-pats.rs:96:12
@@ -581,10 +563,7 @@ error[E0029]: only char and numeric types are allowed in range patterns
   --> $DIR/recover-range-pats.rs:104:15
    |
 LL |     if let ..=true = 0 {}
-   |               ^^^^ ranges require char or numeric types
+   |               ^^^^ this is of type `bool` but it should be `char` or numeric
-   |
-   = note: start type: [type error]
-   = note: end type: bool
 
 error[E0308]: mismatched types
   --> $DIR/recover-range-pats.rs:106:12
@@ -599,10 +578,7 @@ error[E0029]: only char and numeric types are allowed in range patterns
   --> $DIR/recover-range-pats.rs:116:15
    |
 LL |     if let ...true = 0 {}
-   |               ^^^^ ranges require char or numeric types
+   |               ^^^^ this is of type `bool` but it should be `char` or numeric
-   |
-   = note: start type: [type error]
-   = note: end type: bool
 
 error[E0308]: mismatched types
   --> $DIR/recover-range-pats.rs:119:12

src/test/ui/pattern/patkind-litrange-no-expr.stderr

@@ -7,11 +7,11 @@ LL |     Arith = 1 + 1,
 error[E0029]: only char and numeric types are allowed in range patterns
   --> $DIR/patkind-litrange-no-expr.rs:20:13
    |
+LL |                 $( $value ..= 42 => Some($name::$variant), )* // PatKind::Range
+   |                               -- this is of type `{integer}`
+...
 LL |     Arith = 1 + 1,
-   |             ^^^^^ ranges require char or numeric types
+   |             ^^^^^ this is of type `_` but it should be `char` or numeric
-   |
-   = note: start type: {integer}
-   = note: end type: {integer}
 
 error: aborting due to 2 previous errors
 

src/test/ui/qualified/qualified-path-params.stderr

@@ -8,10 +8,9 @@ error[E0029]: only char and numeric types are allowed in range patterns
   --> $DIR/qualified-path-params.rs:22:15
    |
 LL |         0 ..= <S as Tr>::A::f::<u8> => {}
-   |               ^^^^^^^^^^^^^^^^^^^^^ ranges require char or numeric types
+   |         -     ^^^^^^^^^^^^^^^^^^^^^ this is of type `fn() {S::f::<u8>}` but it should be `char` or numeric
-   |
+   |         |
-   = note: start type: {integer}
+   |         this is of type `{integer}`
-   = note: end type: fn() {S::f::<u8>}
 
 error: aborting due to 2 previous errors