Check os_str_display MSRV instead of feature

This feature was stabilized, so the FormatArgs lints should check if the MSRV of
the stabilization is met, rather than checking if the feature is enabled.

Author: flip1995

clippy_lints/src/format_args.rs

@@ -15,6 +15,7 @@ use rustc_ast::{
     FormatArgPosition, FormatArgPositionKind, FormatArgsPiece, FormatArgumentKind, FormatCount, FormatOptions,
     FormatPlaceholder, FormatTrait,
 };
+use rustc_attr_parsing::RustcVersion;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_errors::Applicability;
 use rustc_errors::SuggestionStyle::{CompletelyHidden, ShowCode};
@@ -206,17 +207,17 @@ pub struct FormatArgs<'tcx> {
     format_args: FormatArgsStorage,
     msrv: Msrv,
     ignore_mixed: bool,
-    ty_feature_map: FxHashMap<Ty<'tcx>, Option<Symbol>>,
+    ty_msrv_map: FxHashMap<Ty<'tcx>, Option<RustcVersion>>,
 }
 
 impl<'tcx> FormatArgs<'tcx> {
     pub fn new(tcx: TyCtxt<'tcx>, conf: &'static Conf, format_args: FormatArgsStorage) -> Self {
-        let ty_feature_map = make_ty_feature_map(tcx);
+        let ty_msrv_map = make_ty_msrv_map(tcx);
         Self {
             format_args,
             msrv: conf.msrv.clone(),
             ignore_mixed: conf.allow_mixed_uninlined_format_args,
-            ty_feature_map,
+            ty_msrv_map,
         }
     }
 }
@@ -233,7 +234,8 @@ impl<'tcx> LateLintPass<'tcx> for FormatArgs<'tcx> {
                 macro_call: &macro_call,
                 format_args,
                 ignore_mixed: self.ignore_mixed,
-                ty_feature_map: &self.ty_feature_map,
+                msrv: &self.msrv,
+                ty_msrv_map: &self.ty_msrv_map,
             };
 
             linter.check_templates();
@@ -253,7 +255,8 @@ struct FormatArgsExpr<'a, 'tcx> {
     macro_call: &'a MacroCall,
     format_args: &'a rustc_ast::FormatArgs,
     ignore_mixed: bool,
-    ty_feature_map: &'a FxHashMap<Ty<'tcx>, Option<Symbol>>,
+    msrv: &'a Msrv,
+    ty_msrv_map: &'a FxHashMap<Ty<'tcx>, Option<RustcVersion>>,
 }
 
 impl<'tcx> FormatArgsExpr<'_, 'tcx> {
@@ -538,19 +541,19 @@ impl<'tcx> FormatArgsExpr<'_, 'tcx> {
     fn can_display_format(&self, ty: Ty<'tcx>) -> bool {
         let ty = ty.peel_refs();
 
-        if let Some(feature) = self.ty_feature_map.get(&ty)
-            && feature.is_none_or(|feature| self.cx.tcx.features().enabled(feature))
+        if let Some(msrv) = self.ty_msrv_map.get(&ty)
+            && msrv.is_none_or(|msrv| self.msrv.meets(msrv))
         {
             return true;
         }
 
-        // Even if `ty` is not in `self.ty_feature_map`, check whether `ty` implements `Deref` with
-        // a `Target` that is in `self.ty_feature_map`.
+        // Even if `ty` is not in `self.ty_msrv_map`, check whether `ty` implements `Deref` with
+        // a `Target` that is in `self.ty_msrv_map`.
         if let Some(deref_trait_id) = self.cx.tcx.lang_items().deref_trait()
             && implements_trait(self.cx, ty, deref_trait_id, &[])
             && let Some(target_ty) = self.cx.get_associated_type(ty, deref_trait_id, "Target")
-            && let Some(feature) = self.ty_feature_map.get(&target_ty)
-            && feature.is_none_or(|feature| self.cx.tcx.features().enabled(feature))
+            && let Some(msrv) = self.ty_msrv_map.get(&target_ty)
+            && msrv.is_none_or(|msrv| self.msrv.meets(msrv))
         {
             return true;
         }
@@ -559,8 +562,8 @@ impl<'tcx> FormatArgsExpr<'_, 'tcx> {
     }
 }
 
-fn make_ty_feature_map(tcx: TyCtxt<'_>) -> FxHashMap<Ty<'_>, Option<Symbol>> {
-    [(sym::OsStr, Some(Symbol::intern("os_str_display"))), (sym::Path, None)]
+fn make_ty_msrv_map(tcx: TyCtxt<'_>) -> FxHashMap<Ty<'_>, Option<RustcVersion>> {
+    [(sym::OsStr, Some(msrvs::OS_STR_DISPLAY)), (sym::Path, None)]
         .into_iter()
         .filter_map(|(name, feature)| {
             tcx.get_diagnostic_item(name).map(|def_id| {

clippy_utils/src/msrvs.rs

@@ -19,6 +19,7 @@ macro_rules! msrv_aliases {
 
 // names may refer to stabilized feature flags or library items
 msrv_aliases! {
+    1,87,0 { OS_STR_DISPLAY }
     1,84,0 { CONST_OPTION_AS_SLICE }
     1,83,0 { CONST_EXTERN_FN, CONST_FLOAT_BITS_CONV, CONST_FLOAT_CLASSIFY, CONST_MUT_REFS, CONST_UNWRAP }
     1,82,0 { IS_NONE_OR, REPEAT_N, RAW_REF_OP }