Simplify some conditions

compiler/rustc_ast_passes/src/ast_validation.rs

@@ -623,13 +623,12 @@ fn visit_ty_common(&mut self, ty: &'a Ty) {
     fn maybe_lint_missing_abi(&mut self, span: Span, id: NodeId) {
         // FIXME(davidtwco): This is a hack to detect macros which produce spans of the
         // call site which do not have a macro backtrace. See #61963.
-        let is_macro_callsite = self
+        if self
             .session
             .source_map()
             .span_to_snippet(span)
-            .map(|snippet| snippet.starts_with("#["))
-            .unwrap_or(true);
-        if !is_macro_callsite {
+            .is_ok_and(|snippet| !snippet.starts_with("#["))
+        {
             self.lint_buffer.buffer_lint_with_diagnostic(
                 MISSING_ABI,
                 id,

compiler/rustc_expand/src/config.rs

@@ -445,7 +445,7 @@ pub(crate) fn cfg_true(&self, attr: &Attribute) -> (bool, Option<MetaItem>) {
     /// If attributes are not allowed on expressions, emit an error for `attr`
     #[instrument(level = "trace", skip(self))]
     pub(crate) fn maybe_emit_expr_attr_err(&self, attr: &Attribute) {
-        if !self.features.map_or(true, |features| features.stmt_expr_attributes) {
+        if self.features.is_some_and(|features| !features.stmt_expr_attributes) {
             let mut err = feature_err(
                 &self.sess.parse_sess,
                 sym::stmt_expr_attributes,

compiler/rustc_hir_analysis/src/coherence/inherent_impls_overlap.rs

@@ -140,7 +140,7 @@ fn check_for_overlapping_inherent_impls(
         impl1_def_id: DefId,
         impl2_def_id: DefId,
     ) {
-        traits::overlapping_impls(
+        let maybe_overlap = traits::overlapping_impls(
             self.tcx,
             impl1_def_id,
             impl2_def_id,
@@ -148,11 +148,11 @@ fn check_for_overlapping_inherent_impls(
             // inherent impls without warning.
             SkipLeakCheck::Yes,
             overlap_mode,
-        )
-        .map_or(true, |overlap| {
+        );
+
+        if let Some(overlap) = maybe_overlap {
             self.check_for_common_items_in_impls(impl1_def_id, impl2_def_id, overlap);
-            false
-        });
+        }
     }
 
     fn check_item(&mut self, id: hir::ItemId) {

compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs

@@ -955,9 +955,9 @@ enum SuggestionText {
                         //   - f(0, 1,)
                         //   + f()
                         if only_extras_so_far
-                            && errors
+                            && !errors
                                 .peek()
-                                .map_or(true, |next_error| !matches!(next_error, Error::Extra(_)))
+                                .is_some_and(|next_error| matches!(next_error, Error::Extra(_)))
                         {
                             let next = provided_arg_tys
                                 .get(arg_idx + 1)

compiler/rustc_middle/src/lint.rs

@@ -388,10 +388,11 @@ fn struct_lint_level_impl(
             // it'll become a hard error, so we have to emit *something*. Also,
             // if this lint occurs in the expansion of a macro from an external crate,
             // allow individual lints to opt-out from being reported.
-            let not_future_incompatible =
-                future_incompatible.map(|f| f.reason.edition().is_some()).unwrap_or(true);
-            if not_future_incompatible && !lint.report_in_external_macro {
+            let incompatible = future_incompatible.is_some_and(|f| f.reason.edition().is_none());
+
+            if !incompatible && !lint.report_in_external_macro {
                 err.cancel();
+
                 // Don't continue further, since we don't want to have
                 // `diag_span_note_once` called for a diagnostic that isn't emitted.
                 return;

compiler/rustc_mir_transform/src/coverage/graph.rs

@@ -387,7 +387,7 @@ pub fn set_edge_counter_from(
             // If the BCB has an edge counter (to be injected into a new `BasicBlock`), it can also
             // have an expression (to be injected into an existing `BasicBlock` represented by this
             // `BasicCoverageBlock`).
-            if !self.counter_kind.as_ref().map_or(true, |c| c.is_expression()) {
+            if self.counter_kind.as_ref().is_some_and(|c| !c.is_expression()) {
                 return Error::from_string(format!(
                     "attempt to add an incoming edge counter from {:?} when the target BCB already \
                     has a `Counter`",

compiler/rustc_mir_transform/src/coverage/spans.rs

@@ -480,9 +480,10 @@ fn push_refined_span(&mut self, covspan: CoverageSpan) {
 
     fn check_invoked_macro_name_span(&mut self) {
         if let Some(visible_macro) = self.curr().visible_macro(self.body_span) {
-            if self.prev_expn_span.map_or(true, |prev_expn_span| {
-                self.curr().expn_span.ctxt() != prev_expn_span.ctxt()
-            }) {
+            if !self
+                .prev_expn_span
+                .is_some_and(|prev_expn_span| self.curr().expn_span.ctxt() == prev_expn_span.ctxt())
+            {
                 let merged_prefix_len = self.curr_original_span.lo() - self.curr().span.lo();
                 let after_macro_bang =
                     merged_prefix_len + BytePos(visible_macro.as_str().len() as u32 + 1);

compiler/rustc_parse/src/parser/attr.rs

@@ -422,15 +422,12 @@ fn parse_meta_item_inner(&mut self) -> PResult<'a, ast::NestedMetaItem> {
     }
 }
 
-pub fn maybe_needs_tokens(attrs: &[ast::Attribute]) -> bool {
-    // One of the attributes may either itself be a macro,
-    // or expand to macro attributes (`cfg_attr`).
-    attrs.iter().any(|attr| {
-        if attr.is_doc_comment() {
-            return false;
-        }
-        attr.ident().map_or(true, |ident| {
-            ident.name == sym::cfg_attr || !rustc_feature::is_builtin_attr_name(ident.name)
+/// The attributes are complete if all attributes are either a doc comment or a builtin attribute other than `cfg_attr`
+pub fn is_complete(attrs: &[ast::Attribute]) -> bool {
+    attrs.iter().all(|attr| {
+        attr.is_doc_comment()
+            || attr.ident().is_some_and(|ident| {
+                ident.name != sym::cfg_attr && rustc_feature::is_builtin_attr_name(ident.name)
             })
     })
 }

compiler/rustc_parse/src/parser/attr_wrapper.rs

@@ -61,8 +61,8 @@ pub fn is_empty(&self) -> bool {
         self.attrs.is_empty()
     }
 
-    pub fn maybe_needs_tokens(&self) -> bool {
-        crate::parser::attr::maybe_needs_tokens(&self.attrs)
+    pub fn is_complete(&self) -> bool {
+        crate::parser::attr::is_complete(&self.attrs)
     }
 }
 
@@ -201,7 +201,7 @@ pub fn collect_tokens_trailing_token<R: HasAttrs + HasTokens>(
         //    by definition
         if matches!(force_collect, ForceCollect::No)
             // None of our outer attributes can require tokens (e.g. a proc-macro)
-            && !attrs.maybe_needs_tokens()
+            && attrs.is_complete()
             // If our target supports custom inner attributes, then we cannot bail
             // out early, since we may need to capture tokens for a custom inner attribute
             // invocation.
@@ -244,9 +244,9 @@ pub fn collect_tokens_trailing_token<R: HasAttrs + HasTokens>(
         // Now that we've parsed an AST node, we have more information available.
         if matches!(force_collect, ForceCollect::No)
             // We now have inner attributes available, so this check is more precise
-            // than `attrs.maybe_needs_tokens()` at the start of the function.
+            // than `attrs.is_complete()` at the start of the function.
             // As a result, we don't need to check `R::SUPPORTS_CUSTOM_INNER_ATTRS`
-            && !crate::parser::attr::maybe_needs_tokens(ret.attrs())
+            && crate::parser::attr::is_complete(ret.attrs())
             // Subtle: We call `has_cfg_or_cfg_attr` with the attrs from `ret`.
             // This ensures that we consider inner attributes (e.g. `#![cfg]`),
             // which require us to have tokens available

compiler/rustc_resolve/src/late/diagnostics.rs

@@ -2182,10 +2182,9 @@ pub(crate) fn maybe_report_lifetime_uses(
                 None => {
                     debug!(?param.ident, ?param.ident.span);
                     let deletion_span = deletion_span();
-                    // the give lifetime originates from expanded code so we won't be able to remove it #104432
-                    let lifetime_only_in_expanded_code =
-                        deletion_span.map(|sp| sp.in_derive_expansion()).unwrap_or(true);
-                    if !lifetime_only_in_expanded_code {
+
+                    // if the lifetime originates from expanded code, we won't be able to remove it #104432
+                    if deletion_span.is_some_and(|sp| !sp.in_derive_expansion()) {
                         self.r.lint_buffer.buffer_lint_with_diagnostic(
                             lint::builtin::UNUSED_LIFETIMES,
                             param.id,

compiler/rustc_session/src/parse.rs

@@ -51,13 +51,6 @@ pub fn ungate_last(&self, feature: Symbol, span: Span) {
         debug_assert_eq!(span, removed_span);
     }
 
-    /// Is the provided `feature` gate ungated currently?
-    ///
-    /// Using this is discouraged unless you have a really good reason to.
-    pub fn is_ungated(&self, feature: Symbol) -> bool {
-        self.spans.borrow().get(&feature).map_or(true, |spans| spans.is_empty())
-    }
-
     /// Prepend the given set of `spans` onto the set in `self`.
     pub fn merge(&self, mut spans: FxHashMap<Symbol, Vec<Span>>) {
         let mut inner = self.spans.borrow_mut();