Test lifetimes after types after consts forbidden

Added more complex test and changed error message

src/librustc_ast_passes/ast_validation.rs

@@ -780,13 +780,13 @@ fn validate_generic_param_order<'a>(
         err.span_suggestion(
             span,
             &format!(
-                "reorder the parameters: lifetimes, then types{}",
-                if sess.features_untracked().const_generics
-                    || sess.features_untracked().min_const_generics
-                {
-                    ", then consts"
+                "reorder the parameters: lifetimes{}",
+                if sess.features_untracked().const_generics {
+                    ", then consts and types"
+                } else if sess.features_untracked().min_const_generics {
+                    ", then consts, then types"
                 } else {
-                    ""
+                    ", then types"
                 },
             ),
             ordered_params.clone(),

src/test/ui/const-generics/argument_order.stderr

@@ -2,7 +2,7 @@ error: lifetime parameters must be declared prior to const parameters
   --> $DIR/argument_order.rs:9:32
    |
 LL | struct AlsoBad<const N: usize, 'a, T, 'b, const M: usize, U> {
-   |               -----------------^^-----^^-------------------- help: reorder the parameters: lifetimes, then types, then consts: `<'a, 'b, T, U, const N: usize, const M: usize>`
+   |               -----------------^^-----^^-------------------- help: reorder the parameters: lifetimes, then consts and types: `<'a, 'b, T, U, const N: usize, const M: usize>`
 
 error[E0747]: lifetime provided when a type was expected
   --> $DIR/argument_order.rs:16:23

src/test/ui/const-generics/const-param-before-other-params.stderr

@@ -2,7 +2,7 @@ error: lifetime parameters must be declared prior to const parameters
   --> $DIR/const-param-before-other-params.rs:4:21
    |
 LL | fn bar<const X: (), 'a>(_: &'a ()) {
-   |       --------------^^- help: reorder the parameters: lifetimes, then types, then consts: `<'a, const X: ()>`
+   |       --------------^^- help: reorder the parameters: lifetimes, then consts and types: `<'a, const X: ()>`
 
 error: aborting due to previous error
 

src/test/ui/const-generics/defaults/complex-unord-param.rs

@@ -0,0 +1,28 @@
+// run-pass
+// Checks a complicated usage of unordered params
+
+#![feature(const_generics)]
+#![allow(incomplete_features)]
+#![allow(dead_code)]
+
+struct FixedOutput<'a, const N: usize, T=u32> {
+  out: &'a [T; N],
+}
+
+trait FixedOutputter {
+  fn out(&self) -> FixedOutput<'_, 10>;
+}
+
+struct NestedArrays<'a, const N: usize, A: 'a, const M: usize, T:'a =u32> {
+  args: &'a [&'a [T; M]; N],
+  specifier: A,
+}
+
+fn main() {
+  let array = [1, 2, 3];
+  let nest = [&array];
+  let _ = NestedArrays {
+    args: &nest,
+    specifier: true,
+  };
+}

src/test/ui/const-generics/defaults/intermixed-lifetime.rs

@@ -6,4 +6,7 @@
 struct Foo<const N: usize, 'a, T = u32>(&'a (), T);
 //~^ Error lifetime parameters must be declared prior to const parameters
 
+struct Bar<const N: usize, T = u32, 'a>(&'a (), T);
+//~^ Error lifetime parameters must be declared prior to const parameters
+
 fn main() {}

src/test/ui/const-generics/defaults/intermixed-lifetime.stderr

@@ -2,7 +2,13 @@ error: lifetime parameters must be declared prior to const parameters
   --> $DIR/intermixed-lifetime.rs:6:28
    |
 LL | struct Foo<const N: usize, 'a, T = u32>(&'a (), T);
-   |           -----------------^^---------- help: reorder the parameters: lifetimes, then types, then consts: `<'a, T, const N: usize>`
+   |           -----------------^^---------- help: reorder the parameters: lifetimes, then consts and types: `<'a, T, const N: usize>`
 
-error: aborting due to previous error
+error: lifetime parameters must be declared prior to const parameters
+  --> $DIR/intermixed-lifetime.rs:9:37
+   |
+LL | struct Bar<const N: usize, T = u32, 'a>(&'a (), T);
+   |           --------------------------^^- help: reorder the parameters: lifetimes, then consts and types: `<'a, T, const N: usize>`
+
+error: aborting due to 2 previous errors