Auto merge of rust-lang#13469 - nyurik:apply-ref-option, r=llogiq

Convert `&Option<T>` to `Option<&T>`

Run `ref_option` (rust-lang#13336) on the Clippy's own code, quiet a few hits. Per mentioned video, this may actually improve performance as well.  Switch lint to `pedantic`

----

changelog: [`ref_option`]: upgrade lint to `pedantic`

clippy_lints/src/cargo/common_metadata.rs

@@ -10,27 +10,27 @@ pub(super) fn check(cx: &LateContext<'_>, metadata: &Metadata, ignore_publish: b
         // only run the lint if publish is `None` (`publish = true` or skipped entirely)
         // or if the vector isn't empty (`publish = ["something"]`)
         if package.publish.as_ref().filter(|publish| publish.is_empty()).is_none() || ignore_publish {
-            if is_empty_str(&package.description) {
+            if is_empty_str(package.description.as_ref()) {
                 missing_warning(cx, package, "package.description");
             }
 
-            if is_empty_str(&package.license) && is_empty_str(&package.license_file) {
+            if is_empty_str(package.license.as_ref()) && is_empty_str(package.license_file.as_ref()) {
                 missing_warning(cx, package, "either package.license or package.license_file");
             }
 
-            if is_empty_str(&package.repository) {
+            if is_empty_str(package.repository.as_ref()) {
                 missing_warning(cx, package, "package.repository");
             }
 
-            if is_empty_str(&package.readme) {
+            if is_empty_str(package.readme.as_ref()) {
                 missing_warning(cx, package, "package.readme");
             }
 
-            if is_empty_vec(&package.keywords) {
+            if is_empty_vec(package.keywords.as_ref()) {
                 missing_warning(cx, package, "package.keywords");
             }
 
-            if is_empty_vec(&package.categories) {
+            if is_empty_vec(package.categories.as_ref()) {
                 missing_warning(cx, package, "package.categories");
             }
         }
@@ -42,8 +42,8 @@ fn missing_warning(cx: &LateContext<'_>, package: &cargo_metadata::Package, fiel
     span_lint(cx, CARGO_COMMON_METADATA, DUMMY_SP, message);
 }
 
-fn is_empty_str<T: AsRef<std::ffi::OsStr>>(value: &Option<T>) -> bool {
-    value.as_ref().map_or(true, |s| s.as_ref().is_empty())
+fn is_empty_str<T: AsRef<std::ffi::OsStr>>(value: Option<&T>) -> bool {
+    value.map_or(true, |s| s.as_ref().is_empty())
 }
 
 fn is_empty_vec(value: &[String]) -> bool {

clippy_lints/src/functions/mod.rs

@@ -443,7 +443,7 @@ declare_clippy_lint! {
     /// ```
     #[clippy::version = "1.82.0"]
     pub REF_OPTION,
-    nursery,
+    pedantic,
     "function signature uses `&Option<T>` instead of `Option<&T>`"
 }
 

clippy_lints/src/unnested_or_patterns.rs

@@ -275,12 +275,15 @@ fn transform_with_focus_on_idx(alternatives: &mut ThinVec<P<Pat>>, focus_idx: us
             |k, ps1, idx| matches!(
                 k,
                 TupleStruct(qself2, path2, ps2)
-                    if eq_maybe_qself(qself1, qself2) && eq_path(path1, path2) && eq_pre_post(ps1, ps2, idx)
+                    if eq_maybe_qself(qself1.as_ref(), qself2.as_ref())
+                       && eq_path(path1, path2) && eq_pre_post(ps1, ps2, idx)
             ),
             |k| always_pat!(k, TupleStruct(_, _, ps) => ps),
         ),
         // Transform a record pattern `S { fp_0, ..., fp_n }`.
-        Struct(qself1, path1, fps1, rest1) => extend_with_struct_pat(qself1, path1, fps1, *rest1, start, alternatives),
+        Struct(qself1, path1, fps1, rest1) => {
+            extend_with_struct_pat(qself1.as_ref(), path1, fps1, *rest1, start, alternatives)
+        },
     };
 
     alternatives[focus_idx].kind = focus_kind;
@@ -292,7 +295,7 @@ fn transform_with_focus_on_idx(alternatives: &mut ThinVec<P<Pat>>, focus_idx: us
 /// So when we fixate on some `ident_k: pat_k`, we try to find `ident_k` in the other pattern
 /// and check that all `fp_i` where `i ∈ ((0...n) \ k)` between two patterns are equal.
 fn extend_with_struct_pat(
-    qself1: &Option<P<ast::QSelf>>,
+    qself1: Option<&P<ast::QSelf>>,
     path1: &ast::Path,
     fps1: &mut [ast::PatField],
     rest1: ast::PatFieldsRest,
@@ -307,7 +310,7 @@ fn extend_with_struct_pat(
             |k| {
                 matches!(k, Struct(qself2, path2, fps2, rest2)
                 if rest1 == *rest2 // If one struct pattern has `..` so must the other.
-                && eq_maybe_qself(qself1, qself2)
+                && eq_maybe_qself(qself1, qself2.as_ref())
                 && eq_path(path1, path2)
                 && fps1.len() == fps2.len()
                 && fps1.iter().enumerate().all(|(idx_1, fp1)| {