fix: Specifying reason in expect(clippy::needless_return) no longer t…

…riggers false positive chore: Moved new tests into needless_return.rs chore: Ran cargo uibless Initial commit
rust-lang · Sep 13, 2024 · f5efde7 · f5efde7
1 parent 2b7d80b
commit f5efde7
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Showing 3 changed files with 63 additions and 13 deletions.
diff --git a/clippy_lints/src/returns.rs b/clippy_lints/src/returns.rs
@@ -418,19 +418,29 @@ fn check_final_expr<'tcx>(
             match cx.tcx.hir().attrs(expr.hir_id) {
                 [] => {},
                 [attr] => {
-                    if matches!(Level::from_attr(attr), Some(Level::Expect(_)))
-                        && let metas = attr.meta_item_list()
-                        && let Some(lst) = metas
-                        && let [NestedMetaItem::MetaItem(meta_item)] = lst.as_slice()
-                        && let [tool, lint_name] = meta_item.path.segments.as_slice()
-                        && tool.ident.name == sym::clippy
-                        && matches!(
-                            lint_name.ident.name.as_str(),
-                            "needless_return" | "style" | "all" | "warnings"
-                        )
-                    {
-                        // This is an expectation of the `needless_return` lint
-                    } else {
+                    if !matches!(Level::from_attr(attr), Some(Level::Expect(_))) {
+                        return;
+                    }
+
+                    let Some(metas) = attr.meta_item_list() else {
+                        return;
+                    };
+                    let [NestedMetaItem::MetaItem(meta_item), ..] = metas.as_slice() else {
+                        return;
+                    };
+
+                    let [tool, lint_name] = meta_item.path.segments.as_slice() else {
+                        return;
+                    };
+
+                    if tool.ident.name != sym::clippy {
+                        return;
+                    }
+
+                    if !matches!(
+                        lint_name.ident.name.as_str(),
+                        "needless_return" | "style" | "all" | "warnings"
+                    ) {
                         return;
                     }
                 },

diff --git a/tests/ui/needless_return.fixed b/tests/ui/needless_return.fixed
@@ -360,3 +360,23 @@ fn issue12907() -> String {
 }
 
 fn main() {}
+
+fn a(x: Option<u8>) -> Option<u8> {
+    match x {
+        Some(_) => None,
+        None => {
+            #[expect(clippy::needless_return, reason = "Use early return for errors.")]
+            return None;
+        },
+    }
+}
+
+fn b(x: Option<u8>) -> Option<u8> {
+    match x {
+        Some(_) => None,
+        None => {
+            #[expect(clippy::needless_return)]
+            return None;
+        },
+    }
+}
diff --git a/tests/ui/needless_return.rs b/tests/ui/needless_return.rs
@@ -370,3 +370,23 @@ fn issue12907() -> String {
 }
 
 fn main() {}
+
+fn a(x: Option<u8>) -> Option<u8> {
+    match x {
+        Some(_) => None,
+        None => {
+            #[expect(clippy::needless_return, reason = "Use early return for errors.")]
+            return None;
+        },
+    }
+}
+
+fn b(x: Option<u8>) -> Option<u8> {
+    match x {
+        Some(_) => None,
+        None => {
+            #[expect(clippy::needless_return)]
+            return None;
+        },
+    }
+}