From bda83e6543fa89fd64efafdfb93924fede792850 Mon Sep 17 00:00:00 2001 From: Takayuki Maeda Date: Sun, 10 Jul 2022 03:18:56 +0900 Subject: [PATCH] avoid some `&str` to `String` conversions --- compiler/rustc_borrowck/src/diagnostics/mod.rs | 8 ++++---- compiler/rustc_middle/src/mir/mod.rs | 8 +++----- compiler/rustc_mir_transform/src/check_packed_ref.rs | 4 +--- compiler/rustc_resolve/src/diagnostics.rs | 5 +---- compiler/rustc_resolve/src/late/diagnostics.rs | 6 ++---- compiler/rustc_span/src/hygiene.rs | 3 +-- .../rustc_trait_selection/src/traits/specialize/mod.rs | 2 +- compiler/rustc_typeck/src/check/_match.rs | 2 +- compiler/rustc_typeck/src/check/demand.rs | 4 ++-- compiler/rustc_typeck/src/check/op.rs | 4 ++-- compiler/rustc_typeck/src/hir_wf_check.rs | 2 +- compiler/rustc_typeck/src/lib.rs | 5 ++--- .../src/structured_errors/wrong_number_of_generic_args.rs | 4 ++-- 13 files changed, 23 insertions(+), 34 deletions(-) diff --git a/compiler/rustc_borrowck/src/diagnostics/mod.rs b/compiler/rustc_borrowck/src/diagnostics/mod.rs index 6fea6941085..d296a1a0ac6 100644 --- a/compiler/rustc_borrowck/src/diagnostics/mod.rs +++ b/compiler/rustc_borrowck/src/diagnostics/mod.rs @@ -597,16 +597,16 @@ impl UseSpans<'_> { } /// Describe the span associated with a use of a place. - pub(super) fn describe(&self) -> String { + pub(super) fn describe(&self) -> &str { match *self { UseSpans::ClosureUse { generator_kind, .. } => { if generator_kind.is_some() { - " in generator".to_string() + " in generator" } else { - " in closure".to_string() + " in closure" } } - _ => String::new(), + _ => "", } } diff --git a/compiler/rustc_middle/src/mir/mod.rs b/compiler/rustc_middle/src/mir/mod.rs index e7d7317456c..fa3d05e2f81 100644 --- a/compiler/rustc_middle/src/mir/mod.rs +++ b/compiler/rustc_middle/src/mir/mod.rs @@ -1929,12 +1929,10 @@ impl BorrowKind { } } - pub fn describe_mutability(&self) -> String { + pub fn describe_mutability(&self) -> &str { match *self { - BorrowKind::Shared | BorrowKind::Shallow | BorrowKind::Unique => { - "immutable".to_string() - } - BorrowKind::Mut { .. } => "mutable".to_string(), + BorrowKind::Shared | BorrowKind::Shallow | BorrowKind::Unique => "immutable", + BorrowKind::Mut { .. } => "mutable", } } } diff --git a/compiler/rustc_mir_transform/src/check_packed_ref.rs b/compiler/rustc_mir_transform/src/check_packed_ref.rs index 4bf66cd4c9f..2eb38941f1a 100644 --- a/compiler/rustc_mir_transform/src/check_packed_ref.rs +++ b/compiler/rustc_mir_transform/src/check_packed_ref.rs @@ -39,13 +39,11 @@ fn unsafe_derive_on_repr_packed(tcx: TyCtxt<'_>, def_id: LocalDefId) { let message = if tcx.generics_of(def_id).own_requires_monomorphization() { "`#[derive]` can't be used on a `#[repr(packed)]` struct with \ type or const parameters (error E0133)" - .to_string() } else { "`#[derive]` can't be used on a `#[repr(packed)]` struct that \ does not derive Copy (error E0133)" - .to_string() }; - lint.build(&message).emit(); + lint.build(message).emit(); }); } diff --git a/compiler/rustc_resolve/src/diagnostics.rs b/compiler/rustc_resolve/src/diagnostics.rs index 0f58206eee9..072a52079e3 100644 --- a/compiler/rustc_resolve/src/diagnostics.rs +++ b/compiler/rustc_resolve/src/diagnostics.rs @@ -928,10 +928,7 @@ impl<'a> Resolver<'a> { "generic parameters with a default cannot use \ forward declared identifiers" ); - err.span_label( - span, - "defaulted generic parameters cannot be forward declared".to_string(), - ); + err.span_label(span, "defaulted generic parameters cannot be forward declared"); err } ResolutionError::ParamInTyOfConstParam(name) => { diff --git a/compiler/rustc_resolve/src/late/diagnostics.rs b/compiler/rustc_resolve/src/late/diagnostics.rs index 03cb1cfcfc9..677d7036b2f 100644 --- a/compiler/rustc_resolve/src/late/diagnostics.rs +++ b/compiler/rustc_resolve/src/late/diagnostics.rs @@ -349,10 +349,8 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> { err.code(rustc_errors::error_code!(E0424)); err.span_label(span, match source { - PathSource::Pat => "`self` value is a keyword and may not be bound to variables or shadowed" - .to_string(), - _ => "`self` value is a keyword only available in methods with a `self` parameter" - .to_string(), + PathSource::Pat => "`self` value is a keyword and may not be bound to variables or shadowed", + _ => "`self` value is a keyword only available in methods with a `self` parameter", }); if let Some((fn_kind, span)) = &self.diagnostic_metadata.current_function { // The current function has a `self' parameter, but we were unable to resolve diff --git a/compiler/rustc_span/src/hygiene.rs b/compiler/rustc_span/src/hygiene.rs index 955db72157c..3df4dfb74b3 100644 --- a/compiler/rustc_span/src/hygiene.rs +++ b/compiler/rustc_span/src/hygiene.rs @@ -629,8 +629,7 @@ pub fn debug_hygiene_data(verbose: bool) -> String { if verbose { format!("{:#?}", data) } else { - let mut s = String::from(""); - s.push_str("Expansions:"); + let mut s = String::from("Expansions:"); let mut debug_expn_data = |(id, expn_data): (&ExpnId, &ExpnData)| { s.push_str(&format!( "\n{:?}: parent: {:?}, call_site_ctxt: {:?}, def_site_ctxt: {:?}, kind: {:?}", diff --git a/compiler/rustc_trait_selection/src/traits/specialize/mod.rs b/compiler/rustc_trait_selection/src/traits/specialize/mod.rs index a80354897d6..13848d37890 100644 --- a/compiler/rustc_trait_selection/src/traits/specialize/mod.rs +++ b/compiler/rustc_trait_selection/src/traits/specialize/mod.rs @@ -406,7 +406,7 @@ fn report_conflicting_impls( let mut err = err.build(&msg); match tcx.span_of_impl(overlap.with_impl) { Ok(span) => { - err.span_label(span, "first implementation here".to_string()); + err.span_label(span, "first implementation here"); err.span_label( impl_span, diff --git a/compiler/rustc_typeck/src/check/_match.rs b/compiler/rustc_typeck/src/check/_match.rs index deaadf0e5c8..79e402b542a 100644 --- a/compiler/rustc_typeck/src/check/_match.rs +++ b/compiler/rustc_typeck/src/check/_match.rs @@ -263,7 +263,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { } else if let ExprKind::Block(block, _) = &then_expr.kind && let Some(expr) = &block.expr { - err.span_label(expr.span, "found here".to_string()); + err.span_label(expr.span, "found here"); } err.note("`if` expressions without `else` evaluate to `()`"); err.help("consider adding an `else` block that evaluates to the expected type"); diff --git a/compiler/rustc_typeck/src/check/demand.rs b/compiler/rustc_typeck/src/check/demand.rs index 53ca027bb57..eb7e52c5ed3 100644 --- a/compiler/rustc_typeck/src/check/demand.rs +++ b/compiler/rustc_typeck/src/check/demand.rs @@ -317,9 +317,9 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { .tcx .is_diagnostic_item(sym::Result, expected_adt.did()) { - vec!["Ok(())".to_string()] + vec!["Ok(())"] } else if self.tcx.is_diagnostic_item(sym::Option, expected_adt.did()) { - vec!["None".to_string(), "Some(())".to_string()] + vec!["None", "Some(())"] } else { return; }; diff --git a/compiler/rustc_typeck/src/check/op.rs b/compiler/rustc_typeck/src/check/op.rs index 42893789957..0887c27ea36 100644 --- a/compiler/rustc_typeck/src/check/op.rs +++ b/compiler/rustc_typeck/src/check/op.rs @@ -565,9 +565,9 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { .is_ok() { let (variable_snippet, applicability) = if !fn_sig.inputs().is_empty() { - ("( /* arguments */ )".to_string(), Applicability::HasPlaceholders) + ("( /* arguments */ )", Applicability::HasPlaceholders) } else { - ("()".to_string(), Applicability::MaybeIncorrect) + ("()", Applicability::MaybeIncorrect) }; err.span_suggestion_verbose( diff --git a/compiler/rustc_typeck/src/hir_wf_check.rs b/compiler/rustc_typeck/src/hir_wf_check.rs index 4392b9aada9..5117dc49fb5 100644 --- a/compiler/rustc_typeck/src/hir_wf_check.rs +++ b/compiler/rustc_typeck/src/hir_wf_check.rs @@ -86,7 +86,7 @@ fn diagnostic_hir_wf_check<'tcx>( let errors = fulfill.select_all_or_error(&infcx); if !errors.is_empty() { - tracing::debug!("Wf-check got errors for {:?}: {:?}", ty, errors); + debug!("Wf-check got errors for {:?}: {:?}", ty, errors); for error in errors { if error.obligation.predicate == self.predicate { // Save the cause from the greatest depth - this corresponds diff --git a/compiler/rustc_typeck/src/lib.rs b/compiler/rustc_typeck/src/lib.rs index 08c194ec0b6..dd712fd7ed7 100644 --- a/compiler/rustc_typeck/src/lib.rs +++ b/compiler/rustc_typeck/src/lib.rs @@ -252,7 +252,7 @@ fn check_main_fn_ty(tcx: TyCtxt<'_>, main_def_id: DefId) { let mut diag = struct_span_err!(tcx.sess, generics_param_span.unwrap_or(main_span), E0131, "{}", msg); if let Some(generics_param_span) = generics_param_span { - let label = "`main` cannot have generic parameters".to_string(); + let label = "`main` cannot have generic parameters"; diag.span_label(generics_param_span, label); } diag.emit(); @@ -307,8 +307,7 @@ fn check_main_fn_ty(tcx: TyCtxt<'_>, main_def_id: DefId) { let return_ty_span = main_fn_return_type_span(tcx, main_def_id).unwrap_or(main_span); if !return_ty.bound_vars().is_empty() { let msg = "`main` function return type is not allowed to have generic \ - parameters" - .to_owned(); + parameters"; struct_span_err!(tcx.sess, return_ty_span, E0131, "{}", msg).emit(); error = true; } diff --git a/compiler/rustc_typeck/src/structured_errors/wrong_number_of_generic_args.rs b/compiler/rustc_typeck/src/structured_errors/wrong_number_of_generic_args.rs index 72a32dade4e..265a57c3929 100644 --- a/compiler/rustc_typeck/src/structured_errors/wrong_number_of_generic_args.rs +++ b/compiler/rustc_typeck/src/structured_errors/wrong_number_of_generic_args.rs @@ -126,8 +126,8 @@ impl<'a, 'tcx> WrongNumberOfGenericArgs<'a, 'tcx> { } } - fn kind(&self) -> String { - if self.missing_lifetimes() { "lifetime".to_string() } else { "generic".to_string() } + fn kind(&self) -> &str { + if self.missing_lifetimes() { "lifetime" } else { "generic" } } fn num_provided_args(&self) -> usize {