Unify wording of "failed to resolve" errors with "cannot find" resolution errors

* Use the same wording for all macro resolution errors
* specify the scope in which the resolution failure happened

Before

```
error[E0433]: failed to resolve: `crate` in paths can only be used in start position
  --> $DIR/crate-path-non-absolute.rs:5:22
   |
LL |         let s = ::m::crate::S;
   |                      ^^^^^ `crate` in paths can only be used in start position
```
after
```
error[E0433]: cannot find module `crate` in module `m`
  --> $DIR/crate-path-non-absolute.rs:5:22
   |
LL |         let s = ::m::crate::S;
   |                      ^^^^^ `crate` in paths can only be used in start position
```

Author: estebank

compiler/rustc_resolve/src/build_reduced_graph.rs

@@ -382,9 +382,15 @@ impl<'a, 'ra, 'tcx> BuildReducedGraphVisitor<'a, 'ra, 'tcx> {
                     PathResult::NonModule(partial_res) => {
                         expected_found_error(partial_res.expect_full_res())
                     }
-                    PathResult::Failed { span, label, suggestion, .. } => {
-                        Err(VisResolutionError::FailedToResolve(span, label, suggestion))
-                    }
+                    PathResult::Failed {
+                        span, label, suggestion, segment_name, item_type, ..
+                    } => Err(VisResolutionError::FailedToResolve(
+                        span,
+                        segment_name,
+                        label,
+                        suggestion,
+                        item_type,
+                    )),
                     PathResult::Indeterminate => Err(VisResolutionError::Indeterminate(path.span)),
                 }
             }

compiler/rustc_resolve/src/diagnostics.rs

@@ -792,9 +792,32 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
             ResolutionError::SelfImportOnlyInImportListWithNonEmptyPrefix => {
                 self.dcx().create_err(errs::SelfImportOnlyInImportListWithNonEmptyPrefix { span })
             }
-            ResolutionError::FailedToResolve { segment, label, suggestion, module } => {
-                let mut err =
-                    struct_span_code_err!(self.dcx(), span, E0433, "failed to resolve: {label}");
+            ResolutionError::FailedToResolve { segment, label, suggestion, module, item_type } => {
+                let mut err = struct_span_code_err!(
+                    self.dcx(),
+                    span,
+                    E0433,
+                    "cannot find {item_type} `{segment}` in {}",
+                    match module {
+                        Some(ModuleOrUniformRoot::CurrentScope) | None => "this scope".to_string(),
+                        Some(ModuleOrUniformRoot::Module(module)) => {
+                            match module.kind {
+                                ModuleKind::Def(_, _, None) => {
+                                    "the crate root".to_string()
+                                }
+                                ModuleKind::Def(kind, def_id, Some(name)) => {
+                                    format!("{} `{name}`", kind.descr(def_id))
+                                }
+                                ModuleKind::Block => "this scope".to_string(),
+                            }
+                        }
+                        Some(ModuleOrUniformRoot::CrateRootAndExternPrelude) => {
+                            "the crate root or the list of imported crates".to_string()
+                        }
+                        Some(ModuleOrUniformRoot::ExternPrelude) =>
+                            "the list of imported crates".to_string(),
+                    },
+                );
                 err.span_label(span, label);
 
                 if let Some((suggestions, msg, applicability)) = suggestion {
@@ -806,7 +829,6 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
                 }
                 if let Some(ModuleOrUniformRoot::Module(module)) = module
                     && let Some(module) = module.opt_def_id()
-                    && let Some(segment) = segment
                 {
                     self.find_cfg_stripped(&mut err, &segment, module);
                 }
@@ -1003,10 +1025,18 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
             VisResolutionError::AncestorOnly(span) => {
                 self.dcx().create_err(errs::AncestorOnly(span))
             }
-            VisResolutionError::FailedToResolve(span, label, suggestion) => self.into_struct_error(
-                span,
-                ResolutionError::FailedToResolve { segment: None, label, suggestion, module: None },
-            ),
+            VisResolutionError::FailedToResolve(span, segment, label, suggestion, item_type) => {
+                self.into_struct_error(
+                    span,
+                    ResolutionError::FailedToResolve {
+                        segment,
+                        label,
+                        suggestion,
+                        module: None,
+                        item_type,
+                    },
+                )
+            }
             VisResolutionError::ExpectedFound(span, path_str, res) => {
                 self.dcx().create_err(errs::ExpectedModuleFound { span, res, path_str })
             }