Rollup merge of rust-lang#35373 - oijazsh:E0107, r=jonathandturner

Update E0107 message to new format

Fixes rust-lang#35246 as part of rust-lang#35233.

r? @jonathandturner

Author: eddyb

src/librustc_typeck/astconv.rs

@@ -2273,9 +2273,25 @@ fn check_type_argument_count(tcx: TyCtxt, span: Span, supplied: usize,
 }
 
 fn report_lifetime_number_error(tcx: TyCtxt, span: Span, number: usize, expected: usize) {
-    span_err!(tcx.sess, span, E0107,
-              "wrong number of lifetime parameters: expected {}, found {}",
-              expected, number);
+    let label = if number < expected {
+        if expected == 1 {
+            format!("expected {} lifetime parameter", expected)
+        } else {
+            format!("expected {} lifetime parameters", expected)
+        }
+    } else {
+        let additional = number - expected;
+        if additional == 1 {
+            "unexpected lifetime parameter".to_string()
+        } else {
+            format!("{} unexpected lifetime parameters", additional)
+        }
+    };
+    struct_span_err!(tcx.sess, span, E0107,
+                     "wrong number of lifetime parameters: expected {}, found {}",
+                     expected, number)
+        .span_label(span, &label)
+        .emit();
 }
 
 // A helper struct for conveniently grouping a set of bounds which we pass to

src/test/compile-fail/E0107.rs

@@ -9,16 +9,27 @@
 // except according to those terms.
 
 struct Foo<'a>(&'a str);
+struct Buzz<'a, 'b>(&'a str, &'b str);
 
 enum Bar {
     A,
     B,
     C,
 }
 
-struct Baz<'a> {
-    foo: Foo, //~ ERROR E0107
-    bar: Bar<'a>, //~ ERROR E0107
+struct Baz<'a, 'b, 'c> {
+    foo: Foo,
+    //~^ ERROR E0107
+    //~| expected 1 lifetime parameter
+    buzz: Buzz<'a>,
+    //~^ ERROR E0107
+    //~| expected 2 lifetime parameters
+    bar: Bar<'a>,
+    //~^ ERROR E0107
+    //~| unexpected lifetime parameter
+    foo2: Foo<'a, 'b, 'c>,
+    //~^ ERROR E0107
+    //~| 2 unexpected lifetime parameters
 }
 
 fn main() {