Update invalid crate attributes, add help message

tidy run

update invalid crate attributes, improve error

update test outputs

de-capitalise error

update tests

Update invalid crate attributes, add help message

Update - generate span without using BytePos

Add correct dependancies

Update - generate suggestion without BytePos

Tidy run

update tests

Generate Suggestion without BytePos

Add all builtin attributes

add err builtin inner attr at top of crate

fix tests

add err builtin inner attr at top of crate

tidy fix

add err builtin inner attr at top of crate

Author: tom7980

compiler/rustc_passes/src/check_attr.rs

@@ -1953,28 +1953,52 @@ fn is_c_like_enum(item: &Item<'_>) -> bool {
     }
 }
 
+// FIXME: Fix "Cannot determine resolution" error and remove built-in macros
+// from this check.
 fn check_invalid_crate_level_attr(tcx: TyCtxt<'_>, attrs: &[Attribute]) {
+    // Check for builtin attributes at the crate level
+    // which were unsuccessfully resolved due to cannot determine
+    // resolution for the attribute macro error.
     const ATTRS_TO_CHECK: &[Symbol] = &[
         sym::macro_export,
         sym::repr,
         sym::path,
         sym::automatically_derived,
         sym::start,
         sym::rustc_main,
+        sym::derive,
+        sym::test,
+        sym::test_case,
+        sym::global_allocator,
+        sym::bench,
     ];
 
     for attr in attrs {
-        for attr_to_check in ATTRS_TO_CHECK {
-            if attr.has_name(*attr_to_check) {
-                tcx.sess
-                    .struct_span_err(
+        // This function should only be called with crate attributes
+        // which are inner attributes always but lets check to make sure
+        if attr.style == AttrStyle::Inner {
+            for attr_to_check in ATTRS_TO_CHECK {
+                if attr.has_name(*attr_to_check) {
+                    let mut err = tcx.sess.struct_span_err(
                         attr.span,
                         &format!(
                             "`{}` attribute cannot be used at crate level",
                             attr_to_check.to_ident_string()
                         ),
-                    )
-                    .emit();
+                    );
+                    // Only emit an error with a suggestion if we can create a
+                    // string out of the attribute span
+                    if let Ok(src) = tcx.sess.source_map().span_to_snippet(attr.span) {
+                        let replacement = src.replace("#!", "#");
+                        err.span_suggestion_verbose(
+                            attr.span,
+                            "perhaps you meant to use an outer attribute",
+                            replacement,
+                            rustc_errors::Applicability::MachineApplicable,
+                        );
+                    }
+                    err.emit()
+                }
             }
         }
     }

src/test/ui/derives/issue-36617.rs

@@ -1,3 +1,16 @@
 #![derive(Copy)] //~ ERROR cannot determine resolution for the attribute macro `derive`
+//~^ ERROR `derive` attribute cannot be used at crate level
+
+#![test]//~ ERROR cannot determine resolution for the attribute macro `test`
+//~^ ERROR `test` attribute cannot be used at crate level
+
+#![test_case]//~ ERROR cannot determine resolution for the attribute macro `test_case`
+//~^ ERROR `test_case` attribute cannot be used at crate level
+
+#![bench]//~ ERROR cannot determine resolution for the attribute macro `bench`
+//~^ ERROR `bench` attribute cannot be used at crate level
+
+#![global_allocator]//~ ERROR cannot determine resolution for the attribute macro `global_allocator`
+//~^ ERROR `global_allocator` attribute cannot be used at crate level
 
 fn main() {}

src/test/ui/derives/issue-36617.stderr

@@ -6,5 +6,92 @@ LL | #![derive(Copy)]
    |
    = note: import resolution is stuck, try simplifying macro imports
 
-error: aborting due to previous error
+error: cannot determine resolution for the attribute macro `test`
+  --> $DIR/issue-36617.rs:4:4
+   |
+LL | #![test]
+   |    ^^^^
+   |
+   = note: import resolution is stuck, try simplifying macro imports
+
+error: cannot determine resolution for the attribute macro `test_case`
+  --> $DIR/issue-36617.rs:7:4
+   |
+LL | #![test_case]
+   |    ^^^^^^^^^
+   |
+   = note: import resolution is stuck, try simplifying macro imports
+
+error: cannot determine resolution for the attribute macro `bench`
+  --> $DIR/issue-36617.rs:10:4
+   |
+LL | #![bench]
+   |    ^^^^^
+   |
+   = note: import resolution is stuck, try simplifying macro imports
+
+error: cannot determine resolution for the attribute macro `global_allocator`
+  --> $DIR/issue-36617.rs:13:4
+   |
+LL | #![global_allocator]
+   |    ^^^^^^^^^^^^^^^^
+   |
+   = note: import resolution is stuck, try simplifying macro imports
+
+error: `derive` attribute cannot be used at crate level
+  --> $DIR/issue-36617.rs:1:1
+   |
+LL | #![derive(Copy)]
+   | ^^^^^^^^^^^^^^^^
+   |
+help: perhaps you meant to use an outer attribute
+   |
+LL | #[derive(Copy)]
+   | ~~~~~~~~~~~~~~~
+
+error: `test` attribute cannot be used at crate level
+  --> $DIR/issue-36617.rs:4:1
+   |
+LL | #![test]
+   | ^^^^^^^^
+   |
+help: perhaps you meant to use an outer attribute
+   |
+LL | #[test]
+   | ~~~~~~~
+
+error: `test_case` attribute cannot be used at crate level
+  --> $DIR/issue-36617.rs:7:1
+   |
+LL | #![test_case]
+   | ^^^^^^^^^^^^^
+   |
+help: perhaps you meant to use an outer attribute
+   |
+LL | #[test_case]
+   | ~~~~~~~~~~~~
+
+error: `bench` attribute cannot be used at crate level
+  --> $DIR/issue-36617.rs:10:1
+   |
+LL | #![bench]
+   | ^^^^^^^^^
+   |
+help: perhaps you meant to use an outer attribute
+   |
+LL | #[bench]
+   | ~~~~~~~~
+
+error: `global_allocator` attribute cannot be used at crate level
+  --> $DIR/issue-36617.rs:13:1
+   |
+LL | #![global_allocator]
+   | ^^^^^^^^^^^^^^^^^^^^
+   |
+help: perhaps you meant to use an outer attribute
+   |
+LL | #[global_allocator]
+   | ~~~~~~~~~~~~~~~~~~~
+
+error: aborting due to 10 previous errors
 

src/test/ui/feature-gates/issue-43106-gating-of-bench.rs

@@ -6,5 +6,5 @@
 
 #![bench                   = "4100"]
 //~^ ERROR cannot determine resolution for the attribute macro `bench`
-
+//~^^ ERROR `bench` attribute cannot be used at crate level
 fn main() {}

src/test/ui/feature-gates/issue-43106-gating-of-bench.stderr

@@ -6,5 +6,16 @@ LL | #![bench                   = "4100"]
    |
    = note: import resolution is stuck, try simplifying macro imports
 
-error: aborting due to previous error
+error: `bench` attribute cannot be used at crate level
+  --> $DIR/issue-43106-gating-of-bench.rs:7:1
+   |
+LL | #![bench                   = "4100"]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: perhaps you meant to use an outer attribute
+   |
+LL | #[bench                   = "4100"]
+   |
+
+error: aborting due to 2 previous errors
 

src/test/ui/feature-gates/issue-43106-gating-of-builtin-attrs-error.stderr

@@ -129,36 +129,66 @@ error: `macro_export` attribute cannot be used at crate level
    |
 LL | #![macro_export]
    | ^^^^^^^^^^^^^^^^
+   |
+help: perhaps you meant to use an outer attribute
+   |
+LL | #[macro_export]
+   |
 
 error: `rustc_main` attribute cannot be used at crate level
   --> $DIR/issue-43106-gating-of-builtin-attrs-error.rs:14:1
    |
 LL | #![rustc_main]
    | ^^^^^^^^^^^^^^
+   |
+help: perhaps you meant to use an outer attribute
+   |
+LL | #[rustc_main]
+   | ~~~~~~~~~~~~~
 
 error: `start` attribute cannot be used at crate level
   --> $DIR/issue-43106-gating-of-builtin-attrs-error.rs:16:1
    |
 LL | #![start]
    | ^^^^^^^^^
+   |
+help: perhaps you meant to use an outer attribute
+   |
+LL | #[start]
+   |
 
 error: `repr` attribute cannot be used at crate level
   --> $DIR/issue-43106-gating-of-builtin-attrs-error.rs:18:1
    |
 LL | #![repr()]
    | ^^^^^^^^^^
+   |
+help: perhaps you meant to use an outer attribute
+   |
+LL | #[repr()]
+   |
 
 error: `path` attribute cannot be used at crate level
   --> $DIR/issue-43106-gating-of-builtin-attrs-error.rs:20:1
    |
 LL | #![path = "3800"]
    | ^^^^^^^^^^^^^^^^^
+   |
+help: perhaps you meant to use an outer attribute
+   |
+LL | #[path = "3800"]
+   |
 
 error: `automatically_derived` attribute cannot be used at crate level
   --> $DIR/issue-43106-gating-of-builtin-attrs-error.rs:22:1
    |
 LL | #![automatically_derived]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: perhaps you meant to use an outer attribute
+   |
+LL | #[automatically_derived]
+   |
 
 error[E0518]: attribute should be applied to function or closure
   --> $DIR/issue-43106-gating-of-builtin-attrs-error.rs:36:17

src/test/ui/feature-gates/issue-43106-gating-of-test.rs

@@ -3,5 +3,5 @@
 #![allow(soft_unstable)]
 #![test                    = "4200"]
 //~^ ERROR cannot determine resolution for the attribute macro `test`
-
+//~^^ ERROR `test` attribute cannot be used at crate level
 fn main() {}

src/test/ui/feature-gates/issue-43106-gating-of-test.stderr

@@ -6,5 +6,16 @@ LL | #![test                    = "4200"]
    |
    = note: import resolution is stuck, try simplifying macro imports
 
-error: aborting due to previous error
+error: `test` attribute cannot be used at crate level
+  --> $DIR/issue-43106-gating-of-test.rs:4:1
+   |
+LL | #![test                    = "4200"]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: perhaps you meant to use an outer attribute
+   |
+LL | #[test                    = "4200"]
+   |
+
+error: aborting due to 2 previous errors
 

src/test/ui/imports/issue-28134.rs

@@ -2,3 +2,4 @@
 
 #![allow(soft_unstable)]
 #![test] //~ ERROR cannot determine resolution for the attribute macro `test`
+//~^ ERROR 4:1: 4:9: `test` attribute cannot be used at crate level

src/test/ui/imports/issue-28134.stderr

@@ -6,5 +6,16 @@ LL | #![test]
    |
    = note: import resolution is stuck, try simplifying macro imports
 
-error: aborting due to previous error
+error: `test` attribute cannot be used at crate level
+  --> $DIR/issue-28134.rs:4:1
+   |
+LL | #![test]
+   | ^^^^^^^^
+   |
+help: perhaps you meant to use an outer attribute
+   |
+LL | #[test]
+   | ~~~~~~~
+
+error: aborting due to 2 previous errors