Emit the usages suggestions as multipart suggestions

Author: Urgau

compiler/rustc_lint/src/lints.rs

@@ -1349,7 +1349,7 @@ pub(crate) struct NonUpperCaseGlobal<'a> {
     #[subdiagnostic]
     pub sub: NonUpperCaseGlobalSub,
     #[subdiagnostic]
-    pub usages: Vec<NonUpperCaseGlobalSub>,
+    pub usages: Option<NonUpperCaseGlobalSubUsages>,
 }
 
 #[derive(Subdiagnostic)]
@@ -1367,6 +1367,23 @@ pub(crate) enum NonUpperCaseGlobalSub {
     },
 }
 
+pub(crate) struct NonUpperCaseGlobalSubUsages {
+    pub(crate) spans: Vec<Span>,
+    pub(crate) replace: String,
+}
+
+impl Subdiagnostic for NonUpperCaseGlobalSubUsages {
+    fn add_to_diag<G: EmissionGuarantee>(self, diag: &mut Diag<'_, G>) {
+        if !self.spans.is_empty() {
+            diag.multipart_suggestion_verbose(
+                crate::fluent_generated::_subdiag::suggestion,
+                self.spans.into_iter().map(|sp| (sp, self.replace.clone())).collect(),
+                Applicability::MaybeIncorrect,
+            );
+        }
+    }
+}
+
 // noop_method_call.rs
 #[derive(LintDiagnostic)]
 #[diag(lint_noop_method_call)]

compiler/rustc_lint/src/nonstandard_style.rs

@@ -14,7 +14,7 @@ use {rustc_ast as ast, rustc_hir as hir};
 
 use crate::lints::{
     NonCamelCaseType, NonCamelCaseTypeSub, NonSnakeCaseDiag, NonSnakeCaseDiagSub,
-    NonUpperCaseGlobal, NonUpperCaseGlobalSub,
+    NonUpperCaseGlobal, NonUpperCaseGlobalSub, NonUpperCaseGlobalSubUsages,
 };
 use crate::{EarlyContext, EarlyLintPass, LateContext, LateLintPass, LintContext};
 
@@ -497,12 +497,10 @@ impl NonUpperCaseGlobals {
 
             // We cannot provide meaningful suggestions
             // if the characters are in the category of "Lowercase Letter".
-            let sub = |span| {
-                if *name != uc {
-                    NonUpperCaseGlobalSub::Suggestion { span, replace: uc.clone() }
-                } else {
-                    NonUpperCaseGlobalSub::Label { span }
-                }
+            let sub = if *name != uc {
+                NonUpperCaseGlobalSub::Suggestion { span: ident.span, replace: uc.clone() }
+            } else {
+                NonUpperCaseGlobalSub::Label { span: ident.span }
             };
 
             struct UsageCollector<'a, 'tcx> {
@@ -531,18 +529,23 @@ impl NonUpperCaseGlobals {
                 }
             }
 
-            let usages = if let Some(did) = did {
+            let usages = if let Some(did) = did
+                && *name != uc
+            {
                 let mut usage_collector = UsageCollector { cx, did, collected: Vec::new() };
                 cx.tcx.hir_walk_toplevel_module(&mut usage_collector);
-                usage_collector.collected.into_iter().map(|span| sub(span)).collect()
+                Some(NonUpperCaseGlobalSubUsages {
+                    spans: usage_collector.collected,
+                    replace: uc.clone(),
+                })
             } else {
-                vec![]
+                None
             };
 
             cx.emit_span_lint(
                 NON_UPPER_CASE_GLOBALS,
                 ident.span,
-                NonUpperCaseGlobal { sort, name, sub: sub(ident.span), usages },
+                NonUpperCaseGlobal { sort, name, sub, usages },
             );
         }
     }

tests/ui/lint/lint-non-uppercase-usages.fixed

@@ -30,10 +30,8 @@ fn foo<const FOO: u32>() {
 
 fn main() {
     let _a = crate::MY_STATIC;
-    //~^ SUGGESTION MY_STATIC
 
     FOO_FOO.set(9);
     //~^ SUGGESTION FOO_FOO
     println!("{}", FOO_FOO.get());
-    //~^ SUGGESTION FOO_FOO
 }

tests/ui/lint/lint-non-uppercase-usages.rs

@@ -30,10 +30,8 @@ fn foo<const foo: u32>() {
 
 fn main() {
     let _a = crate::my_static;
-    //~^ SUGGESTION MY_STATIC
 
     fooFOO.set(9);
     //~^ SUGGESTION FOO_FOO
     println!("{}", fooFOO.get());
-    //~^ SUGGESTION FOO_FOO
 }

tests/ui/lint/lint-non-uppercase-usages.stderr

@@ -12,13 +12,11 @@ LL + const MY_STATIC: u32 = 0;
    |
 help: convert the identifier to upper case
    |
-LL - const LOL: u32 = my_static + 0;
-LL + const LOL: u32 = MY_STATIC + 0;
-   |
-help: convert the identifier to upper case
-   |
-LL -     let _a = crate::my_static;
-LL +     let _a = crate::MY_STATIC;
+LL ~ const LOL: u32 = MY_STATIC + 0;
+LL |
+...
+LL | fn main() {
+LL ~     let _a = crate::MY_STATIC;
    |
 
 warning: constant `fooFOO` should have an upper case name
@@ -34,13 +32,9 @@ LL +     static FOO_FOO: Cell<usize> = unreachable!();
    |
 help: convert the identifier to upper case
    |
-LL -     fooFOO.set(9);
-LL +     FOO_FOO.set(9);
-   |
-help: convert the identifier to upper case
-   |
-LL -     println!("{}", fooFOO.get());
-LL +     println!("{}", FOO_FOO.get());
+LL ~     FOO_FOO.set(9);
+LL |
+LL ~     println!("{}", FOO_FOO.get());
    |
 
 warning: const parameter `foo` should have an upper case name