new lint unnecessary_map_or

Author: Jacherr

CHANGELOG.md

@@ -5740,6 +5740,7 @@ Released 2018-09-13
 [`unnecessary_lazy_evaluations`]: https://rust-lang.github.io/rust-clippy/master/index.html#unnecessary_lazy_evaluations
 [`unnecessary_literal_unwrap`]: https://rust-lang.github.io/rust-clippy/master/index.html#unnecessary_literal_unwrap
 [`unnecessary_map_on_constructor`]: https://rust-lang.github.io/rust-clippy/master/index.html#unnecessary_map_on_constructor
+[`unnecessary_map_or`]: https://rust-lang.github.io/rust-clippy/master/index.html#unnecessary_map_or
 [`unnecessary_mut_passed`]: https://rust-lang.github.io/rust-clippy/master/index.html#unnecessary_mut_passed
 [`unnecessary_operation`]: https://rust-lang.github.io/rust-clippy/master/index.html#unnecessary_operation
 [`unnecessary_owned_empty_strings`]: https://rust-lang.github.io/rust-clippy/master/index.html#unnecessary_owned_empty_strings

clippy_dev/src/setup/vscode.rs

@@ -84,7 +84,7 @@ fn delete_vs_task_file(path: &Path) -> bool {
 /// It may fail silently.
 fn try_delete_vs_directory_if_empty() {
     let path = Path::new(VSCODE_DIR);
-    if path.read_dir().map_or(false, |mut iter| iter.next().is_none()) {
+    if path.read_dir().is_ok_and(|mut iter| iter.next().is_none()) {
         // The directory is empty. We just try to delete it but allow a silence
         // fail as an empty `.vscode` directory is still valid
         let _silence_result = fs::remove_dir(path);

clippy_lints/src/attrs/useless_attribute.rs

@@ -16,7 +16,7 @@ pub(super) fn check(cx: &LateContext<'_>, item: &Item<'_>, attrs: &[Attribute])
             return;
         }
         if let Some(lint_list) = &attr.meta_item_list() {
-            if attr.ident().map_or(false, |ident| is_lint_level(ident.name, attr.id)) {
+            if attr.ident().is_some_and(|ident| is_lint_level(ident.name, attr.id)) {
                 for lint in lint_list {
                     match item.kind {
                         ItemKind::Use(..) => {
@@ -25,7 +25,7 @@ pub(super) fn check(cx: &LateContext<'_>, item: &Item<'_>, attrs: &[Attribute])
                                 || is_word(lint, sym!(unreachable_pub))
                                 || is_word(lint, sym!(unused))
                                 || is_word(lint, sym!(unused_import_braces))
-                                || extract_clippy_lint(lint).map_or(false, |s| {
+                                || extract_clippy_lint(lint).is_some_and(|s| {
                                     matches!(
                                         s.as_str(),
                                         "wildcard_imports"

clippy_lints/src/attrs/utils.rs

@@ -50,7 +50,7 @@ fn is_relevant_block(cx: &LateContext<'_>, typeck_results: &ty::TypeckResults<'_
         block
             .expr
             .as_ref()
-            .map_or(false, |e| is_relevant_expr(cx, typeck_results, e)),
+            .is_some_and(|e| is_relevant_expr(cx, typeck_results, e)),
         |stmt| match &stmt.kind {
             StmtKind::Local(_) => true,
             StmtKind::Expr(expr) | StmtKind::Semi(expr) => is_relevant_expr(cx, typeck_results, expr),
@@ -60,7 +60,7 @@ fn is_relevant_block(cx: &LateContext<'_>, typeck_results: &ty::TypeckResults<'_
 }
 
 fn is_relevant_expr(cx: &LateContext<'_>, typeck_results: &ty::TypeckResults<'_>, expr: &Expr<'_>) -> bool {
-    if macro_backtrace(expr.span).last().map_or(false, |macro_call| {
+    if macro_backtrace(expr.span).last().is_some_and(|macro_call| {
         is_panic(cx, macro_call.def_id) || cx.tcx.item_name(macro_call.def_id) == sym::unreachable
     }) {
         return false;

clippy_lints/src/bool_assert_comparison.rs

@@ -60,7 +60,7 @@ fn is_impl_not_trait_with_bool_out<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>) -
                 trait_id,
             )
         })
-        .map_or(false, |assoc_item| {
+        .is_some_and(|assoc_item| {
             let proj = Ty::new_projection(cx.tcx, assoc_item.def_id, cx.tcx.mk_args_trait(ty, []));
             let nty = cx.tcx.normalize_erasing_regions(cx.param_env, proj);
 

clippy_lints/src/booleans.rs

@@ -577,7 +577,7 @@ fn implements_ord(cx: &LateContext<'_>, expr: &Expr<'_>) -> bool {
     let ty = cx.typeck_results().expr_ty(expr);
     cx.tcx
         .get_diagnostic_item(sym::Ord)
-        .map_or(false, |id| implements_trait(cx, ty, id, &[]))
+        .is_some_and(|id| implements_trait(cx, ty, id, &[]))
 }
 
 struct NotSimplificationVisitor<'a, 'tcx> {

clippy_lints/src/box_default.rs

@@ -50,7 +50,7 @@ impl LateLintPass<'_> for BoxDefault {
             // And that method is `new`
             && seg.ident.name == sym::new
             // And the call is that of a `Box` method
-            && path_def_id(cx, ty).map_or(false, |id| Some(id) == cx.tcx.lang_items().owned_box())
+            && path_def_id(cx, ty).is_some_and(|id| Some(id) == cx.tcx.lang_items().owned_box())
             // And the single argument to the call is another function call
             // This is the `T::default()` of `Box::new(T::default())`
             && let ExprKind::Call(arg_path, inner_call_args) = arg.kind
@@ -60,6 +60,7 @@ impl LateLintPass<'_> for BoxDefault {
             // or that we are inside a `vec!` macro expansion
             && (expr.span.eq_ctxt(arg.span) || is_local_vec_expn(cx, arg, expr))
             // And the argument is equivalent to `Default::default()`
+            && path_def_id(cx, ty).is_some_and(|id| Some(id) == cx.tcx.lang_items().owned_box())
             && is_default_equivalent(cx, arg)
         {
             span_lint_and_sugg(
@@ -118,9 +119,9 @@ fn explicit_default_type<'a>(arg_path: &'a Expr<'_>) -> Option<&'a Ty<'a>> {
 }
 
 fn is_local_vec_expn(cx: &LateContext<'_>, expr: &Expr<'_>, ref_expr: &Expr<'_>) -> bool {
-    macro_backtrace(expr.span).next().map_or(false, |call| {
-        cx.tcx.is_diagnostic_item(sym::vec_macro, call.def_id) && call.span.eq_ctxt(ref_expr.span)
-    })
+    macro_backtrace(expr.span)
+        .next()
+        .is_some_and(|call| cx.tcx.is_diagnostic_item(sym::vec_macro, call.def_id) && call.span.eq_ctxt(ref_expr.span))
 }
 
 #[derive(Default)]

clippy_lints/src/casts/unnecessary_cast.rs

@@ -159,8 +159,7 @@ pub(super) fn check<'tcx>(
         // The same is true if the expression encompassing the cast expression is a unary
         // expression or an addressof expression.
         let needs_block = matches!(cast_expr.kind, ExprKind::Unary(..) | ExprKind::AddrOf(..))
-            || get_parent_expr(cx, expr)
-                .map_or(false, |e| matches!(e.kind, ExprKind::Unary(..) | ExprKind::AddrOf(..)));
+            || get_parent_expr(cx, expr).is_some_and(|e| matches!(e.kind, ExprKind::Unary(..) | ExprKind::AddrOf(..)));
 
         span_lint_and_sugg(
             cx,

clippy_lints/src/comparison_chain.rs

@@ -110,7 +110,7 @@ impl<'tcx> LateLintPass<'tcx> for ComparisonChain {
                 let is_ord = cx
                     .tcx
                     .get_diagnostic_item(sym::Ord)
-                    .map_or(false, |id| implements_trait(cx, ty, id, &[]));
+                    .is_some_and(|id| implements_trait(cx, ty, id, &[]));
 
                 if !is_ord {
                     return;

clippy_lints/src/copies.rs

@@ -272,7 +272,7 @@ fn lint_branches_sharing_code<'tcx>(
         let span = span.with_hi(last_block.span.hi());
         // Improve formatting if the inner block has indention (i.e. normal Rust formatting)
         let test_span = Span::new(span.lo() - BytePos(4), span.lo(), span.ctxt(), span.parent());
-        let span = if snippet_opt(cx, test_span).map_or(false, |snip| snip == "    ") {
+        let span = if snippet_opt(cx, test_span).is_some_and(|snip| snip == "    ") {
             span.with_lo(test_span.lo())
         } else {
             span
@@ -353,7 +353,7 @@ fn eq_binding_names(s: &Stmt<'_>, names: &[(HirId, Symbol)]) -> bool {
         let mut i = 0usize;
         let mut res = true;
         l.pat.each_binding_or_first(&mut |_, _, _, name| {
-            if names.get(i).map_or(false, |&(_, n)| n == name.name) {
+            if names.get(i).is_some_and(|&(_, n)| n == name.name) {
                 i += 1;
             } else {
                 res = false;
@@ -397,12 +397,10 @@ fn eq_stmts(
         let new_bindings = &moved_bindings[old_count..];
         blocks
             .iter()
-            .all(|b| get_stmt(b).map_or(false, |s| eq_binding_names(s, new_bindings)))
+            .all(|b| get_stmt(b).is_some_and(|s| eq_binding_names(s, new_bindings)))
     } else {
         true
-    }) && blocks
-        .iter()
-        .all(|b| get_stmt(b).map_or(false, |s| eq.eq_stmt(s, stmt)))
+    }) && blocks.iter().all(|b| get_stmt(b).is_some_and(|s| eq.eq_stmt(s, stmt)))
 }
 
 #[expect(clippy::too_many_lines)]
@@ -459,9 +457,7 @@ fn scan_block_for_eq<'tcx>(
     //     x + 50
     let expr_hash_eq = if let Some(e) = block.expr {
         let hash = hash_expr(cx, e);
-        blocks
-            .iter()
-            .all(|b| b.expr.map_or(false, |e| hash_expr(cx, e) == hash))
+        blocks.iter().all(|b| b.expr.is_some_and(|e| hash_expr(cx, e) == hash))
     } else {
         blocks.iter().all(|b| b.expr.is_none())
     };
@@ -522,7 +518,7 @@ fn scan_block_for_eq<'tcx>(
         });
     if let Some(e) = block.expr {
         for block in blocks {
-            if block.expr.map_or(false, |expr| !eq.eq_expr(expr, e)) {
+            if block.expr.is_some_and(|expr| !eq.eq_expr(expr, e)) {
                 moved_locals.truncate(moved_locals_at_start);
                 return BlockEq {
                     start_end_eq,
@@ -541,7 +537,7 @@ fn scan_block_for_eq<'tcx>(
 }
 
 fn check_for_warn_of_moved_symbol(cx: &LateContext<'_>, symbols: &[(HirId, Symbol)], if_expr: &Expr<'_>) -> bool {
-    get_enclosing_block(cx, if_expr.hir_id).map_or(false, |block| {
+    get_enclosing_block(cx, if_expr.hir_id).is_some_and(|block| {
         let ignore_span = block.span.shrink_to_lo().to(if_expr.span);
 
         symbols