From 8e9422f94e6717721ffbad50862fcef9822c2537 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Esteban=20K=C3=BCber?= Date: Fri, 31 Jan 2025 20:36:44 +0000 Subject: [PATCH] Make comma separated lists of anything easier to make for errors Provide a new function `listify`, meant to be used in cases similar to `pluralize!`. When you have a slice of arbitrary elements that need to be presented to the user, `listify` allows you to turn that into a list of comma separated strings. This reduces a lot of redundant logic that happens often in diagnostics. --- .../rustc_borrowck/src/diagnostics/mod.rs | 20 ++++---- compiler/rustc_builtin_macros/src/format.rs | 18 ++++---- compiler/rustc_errors/src/lib.rs | 14 +----- .../src/hir_ty_lowering/errors.rs | 46 ++++--------------- compiler/rustc_hir_typeck/src/demand.rs | 20 ++++---- compiler/rustc_hir_typeck/src/expr.rs | 35 +++++--------- .../rustc_hir_typeck/src/fn_ctxt/checks.rs | 12 +++-- .../src/fn_ctxt/suggestions.rs | 14 ++---- compiler/rustc_lint_defs/src/lib.rs | 17 +++++++ compiler/rustc_middle/src/ty/diagnostics.rs | 16 +++---- compiler/rustc_privacy/src/lib.rs | 24 ++-------- 11 files changed, 88 insertions(+), 148 deletions(-) diff --git a/compiler/rustc_borrowck/src/diagnostics/mod.rs b/compiler/rustc_borrowck/src/diagnostics/mod.rs index bd6f77156ca99..d13b4bde5765f 100644 --- a/compiler/rustc_borrowck/src/diagnostics/mod.rs +++ b/compiler/rustc_borrowck/src/diagnostics/mod.rs @@ -4,7 +4,7 @@ use std::collections::BTreeMap; use rustc_abi::{FieldIdx, VariantIdx}; use rustc_data_structures::fx::FxIndexMap; -use rustc_errors::{Applicability, Diag, EmissionGuarantee, MultiSpan}; +use rustc_errors::{Applicability, Diag, EmissionGuarantee, MultiSpan, listify}; use rustc_hir::def::{CtorKind, Namespace}; use rustc_hir::{self as hir, CoroutineKind, LangItem}; use rustc_index::IndexSlice; @@ -29,7 +29,7 @@ use rustc_trait_selection::error_reporting::InferCtxtErrorExt; use rustc_trait_selection::error_reporting::traits::call_kind::{CallDesugaringKind, call_kind}; use rustc_trait_selection::infer::InferCtxtExt; use rustc_trait_selection::traits::{ - FulfillmentErrorCode, type_known_to_meet_bound_modulo_regions, + FulfillmentError, FulfillmentErrorCode, type_known_to_meet_bound_modulo_regions, }; use tracing::debug; @@ -1436,17 +1436,15 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> { error.obligation.predicate, ) } - [errors @ .., last] => { + _ => { format!( "you could `clone` the value and consume it, if the \ - following trait bounds could be satisfied: \ - {} and `{}`", - errors - .iter() - .map(|e| format!("`{}`", e.obligation.predicate)) - .collect::>() - .join(", "), - last.obligation.predicate, + following trait bounds could be satisfied: {}", + listify(&errors, |e: &FulfillmentError<'tcx>| format!( + "`{}`", + e.obligation.predicate + )) + .unwrap(), ) } }; diff --git a/compiler/rustc_builtin_macros/src/format.rs b/compiler/rustc_builtin_macros/src/format.rs index 7c746bd719f31..90447da66807b 100644 --- a/compiler/rustc_builtin_macros/src/format.rs +++ b/compiler/rustc_builtin_macros/src/format.rs @@ -8,7 +8,9 @@ use rustc_ast::{ token, }; use rustc_data_structures::fx::FxHashSet; -use rustc_errors::{Applicability, Diag, MultiSpan, PResult, SingleLabelManySpans}; +use rustc_errors::{ + Applicability, Diag, MultiSpan, PResult, SingleLabelManySpans, listify, pluralize, +}; use rustc_expand::base::*; use rustc_lint_defs::builtin::NAMED_ARGUMENTS_USED_POSITIONALLY; use rustc_lint_defs::{BufferedEarlyLint, BuiltinLintDiag, LintId}; @@ -975,15 +977,11 @@ fn report_invalid_references( } else { MultiSpan::from_spans(invalid_refs.iter().filter_map(|&(_, span, _, _)| span).collect()) }; - let arg_list = if let &[index] = &indexes[..] { - format!("argument {index}") - } else { - let tail = indexes.pop().unwrap(); - format!( - "arguments {head} and {tail}", - head = indexes.into_iter().map(|i| i.to_string()).collect::>().join(", ") - ) - }; + let arg_list = format!( + "argument{} {}", + pluralize!(indexes.len()), + listify(&indexes, |i: &usize| i.to_string()).unwrap_or_default() + ); e = ecx.dcx().struct_span_err( span, format!("invalid reference to positional {arg_list} ({num_args_desc})"), diff --git a/compiler/rustc_errors/src/lib.rs b/compiler/rustc_errors/src/lib.rs index 549729548f537..a6458c9ffdcdb 100644 --- a/compiler/rustc_errors/src/lib.rs +++ b/compiler/rustc_errors/src/lib.rs @@ -65,7 +65,7 @@ pub use rustc_error_messages::{ SubdiagMessage, fallback_fluent_bundle, fluent_bundle, }; use rustc_lint_defs::LintExpectationId; -pub use rustc_lint_defs::{Applicability, pluralize}; +pub use rustc_lint_defs::{Applicability, listify, pluralize}; use rustc_macros::{Decodable, Encodable}; pub use rustc_span::ErrorGuaranteed; pub use rustc_span::fatal_error::{FatalError, FatalErrorMarker}; @@ -1999,18 +1999,6 @@ pub fn a_or_an(s: &str) -> &'static str { } } -/// Grammatical tool for displaying messages to end users in a nice form. -/// -/// Take a list ["a", "b", "c"] and output a display friendly version "a, b and c" -pub fn display_list_with_comma_and(v: &[T]) -> String { - match v { - [] => "".to_string(), - [a] => a.to_string(), - [a, b] => format!("{a} and {b}"), - [a, v @ ..] => format!("{a}, {}", display_list_with_comma_and(v)), - } -} - #[derive(Clone, Copy, PartialEq, Hash, Debug)] pub enum TerminalUrl { No, diff --git a/compiler/rustc_hir_analysis/src/hir_ty_lowering/errors.rs b/compiler/rustc_hir_analysis/src/hir_ty_lowering/errors.rs index 36b214b6ae734..79aa2f4b8ccd2 100644 --- a/compiler/rustc_hir_analysis/src/hir_ty_lowering/errors.rs +++ b/compiler/rustc_hir_analysis/src/hir_ty_lowering/errors.rs @@ -3,7 +3,7 @@ use rustc_data_structures::sorted_map::SortedMap; use rustc_data_structures::unord::UnordMap; use rustc_errors::codes::*; use rustc_errors::{ - Applicability, Diag, ErrorGuaranteed, MultiSpan, pluralize, struct_span_code_err, + Applicability, Diag, ErrorGuaranteed, MultiSpan, listify, pluralize, struct_span_code_err, }; use rustc_hir as hir; use rustc_hir::def::{DefKind, Res}; @@ -808,14 +808,10 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ { .map(|(trait_, mut assocs)| { assocs.sort(); let trait_ = trait_.print_trait_sugared(); - format!("{} in `{trait_}`", match &assocs[..] { - [] => String::new(), - [only] => format!("`{only}`"), - [assocs @ .., last] => format!( - "{} and `{last}`", - assocs.iter().map(|a| format!("`{a}`")).collect::>().join(", ") - ), - }) + format!( + "{} in `{trait_}`", + listify(&assocs[..], |a| format!("`{a}`")).unwrap_or_default() + ) }) .collect::>(); names.sort(); @@ -1075,18 +1071,8 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ { } }) .collect(); - let this_type = match &types_and_spans[..] { - [.., _, (last, _)] => format!( - "{} and {last}", - types_and_spans[..types_and_spans.len() - 1] - .iter() - .map(|(x, _)| x.as_str()) - .intersperse(", ") - .collect::() - ), - [(only, _)] => only.to_string(), - [] => bug!("expected one segment to deny"), - }; + let this_type = listify(&types_and_spans, |(t, _)| t.to_string()) + .expect("expected one segment to deny"); let arg_spans: Vec = segments .clone() @@ -1102,21 +1088,9 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ { ProhibitGenericsArg::Infer => kinds.push("generic"), }); - let (kind, s) = match kinds[..] { - [.., _, last] => ( - format!( - "{} and {last}", - kinds[..kinds.len() - 1] - .iter() - .map(|&x| x) - .intersperse(", ") - .collect::() - ), - "s", - ), - [only] => (only.to_string(), ""), - [] => bug!("expected at least one generic to prohibit"), - }; + let s = pluralize!(kinds.len()); + let kind = + listify(&kinds, |k| k.to_string()).expect("expected at least one generic to prohibit"); let last_span = *arg_spans.last().unwrap(); let span: MultiSpan = arg_spans.into(); let mut err = struct_span_code_err!( diff --git a/compiler/rustc_hir_typeck/src/demand.rs b/compiler/rustc_hir_typeck/src/demand.rs index bc0766705854a..85e949952f8de 100644 --- a/compiler/rustc_hir_typeck/src/demand.rs +++ b/compiler/rustc_hir_typeck/src/demand.rs @@ -1,4 +1,4 @@ -use rustc_errors::{Applicability, Diag, MultiSpan}; +use rustc_errors::{Applicability, Diag, MultiSpan, listify}; use rustc_hir as hir; use rustc_hir::def::Res; use rustc_hir::intravisit::Visitor; @@ -1016,18 +1016,14 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { }, self.tcx.def_path_str(candidate.item.container_id(self.tcx)) ), - [.., last] if other_methods_in_scope.len() < 5 => { + _ if other_methods_in_scope.len() < 5 => { format!( - "the methods of the same name on {} and `{}`", - other_methods_in_scope[..other_methods_in_scope.len() - 1] - .iter() - .map(|c| format!( - "`{}`", - self.tcx.def_path_str(c.item.container_id(self.tcx)) - )) - .collect::>() - .join(", "), - self.tcx.def_path_str(last.item.container_id(self.tcx)) + "the methods of the same name on {}", + listify( + &other_methods_in_scope[..other_methods_in_scope.len() - 1], + |c| format!("`{}`", self.tcx.def_path_str(c.item.container_id(self.tcx))) + ) + .unwrap_or_default(), ) } _ => format!( diff --git a/compiler/rustc_hir_typeck/src/expr.rs b/compiler/rustc_hir_typeck/src/expr.rs index f79667e59bae1..0582a7dcee171 100644 --- a/compiler/rustc_hir_typeck/src/expr.rs +++ b/compiler/rustc_hir_typeck/src/expr.rs @@ -11,7 +11,7 @@ use rustc_data_structures::stack::ensure_sufficient_stack; use rustc_data_structures::unord::UnordMap; use rustc_errors::codes::*; use rustc_errors::{ - Applicability, Diag, ErrorGuaranteed, MultiSpan, StashKey, Subdiagnostic, pluralize, + Applicability, Diag, ErrorGuaranteed, MultiSpan, StashKey, Subdiagnostic, listify, pluralize, struct_span_code_err, }; use rustc_hir::def::{CtorKind, DefKind, Res}; @@ -2190,13 +2190,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { } if !missing_mandatory_fields.is_empty() { let s = pluralize!(missing_mandatory_fields.len()); - let fields: Vec<_> = - missing_mandatory_fields.iter().map(|f| format!("`{f}`")).collect(); - let fields = match &fields[..] { - [] => unreachable!(), - [only] => only.to_string(), - [start @ .., last] => format!("{} and {last}", start.join(", ")), - }; + let fields = listify(&missing_mandatory_fields, |f| format!("`{f}`")).unwrap(); self.dcx() .struct_span_err( span.shrink_to_hi(), @@ -2553,25 +2547,20 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { .partition(|field| field.2); err.span_labels(used_private_fields.iter().map(|(_, span, _)| *span), "private field"); if !remaining_private_fields.is_empty() { - let remaining_private_fields_len = remaining_private_fields.len(); - let names = match &remaining_private_fields - .iter() - .map(|(name, _, _)| name) - .collect::>()[..] - { - _ if remaining_private_fields_len > 6 => String::new(), - [name] => format!("`{name}` "), - [names @ .., last] => { - let names = names.iter().map(|name| format!("`{name}`")).collect::>(); - format!("{} and `{last}` ", names.join(", ")) - } - [] => bug!("expected at least one private field to report"), + let names = if remaining_private_fields.len() > 6 { + String::new() + } else { + format!( + "{} ", + listify(&remaining_private_fields, |(name, _, _)| format!("`{name}`")) + .expect("expected at least one private field to report") + ) }; err.note(format!( "{}private field{s} {names}that {were} not provided", if used_fields.is_empty() { "" } else { "...and other " }, - s = pluralize!(remaining_private_fields_len), - were = pluralize!("was", remaining_private_fields_len), + s = pluralize!(remaining_private_fields.len()), + were = pluralize!("was", remaining_private_fields.len()), )); } diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs index fb5fc109ce467..bbe653714962e 100644 --- a/compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs +++ b/compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs @@ -4,8 +4,7 @@ use itertools::Itertools; use rustc_data_structures::fx::FxIndexSet; use rustc_errors::codes::*; use rustc_errors::{ - Applicability, Diag, ErrorGuaranteed, MultiSpan, StashKey, a_or_an, - display_list_with_comma_and, pluralize, + Applicability, Diag, ErrorGuaranteed, MultiSpan, StashKey, a_or_an, listify, pluralize, }; use rustc_hir::def::{CtorOf, DefKind, Res}; use rustc_hir::def_id::DefId; @@ -2462,7 +2461,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { param.span, format!( "{} need{} to match the {} type of this parameter", - display_list_with_comma_and(&other_param_matched_names), + listify(&other_param_matched_names, |n| n.to_string()) + .unwrap_or_default(), pluralize!(if other_param_matched_names.len() == 1 { 0 } else { @@ -2477,7 +2477,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { format!( "this parameter needs to match the {} type of {}", matched_ty, - display_list_with_comma_and(&other_param_matched_names), + listify(&other_param_matched_names, |n| n.to_string()) + .unwrap_or_default(), ), ); } @@ -2523,7 +2524,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { generic_param.span, format!( "{} {} reference this parameter `{}`", - display_list_with_comma_and(¶m_idents_matching), + listify(¶m_idents_matching, |n| n.to_string()) + .unwrap_or_default(), if param_idents_matching.len() == 2 { "both" } else { "all" }, generic_param.name.ident().name, ), diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs index 60f9265bfcc0d..beddbf971fd3e 100644 --- a/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs +++ b/compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs @@ -4,7 +4,7 @@ use core::iter; use hir::def_id::LocalDefId; use rustc_ast::util::parser::ExprPrecedence; use rustc_data_structures::packed::Pu128; -use rustc_errors::{Applicability, Diag, MultiSpan}; +use rustc_errors::{Applicability, Diag, MultiSpan, listify}; use rustc_hir::def::{CtorKind, CtorOf, DefKind, Res}; use rustc_hir::lang_items::LangItem; use rustc_hir::{ @@ -1836,16 +1836,12 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { error.obligation.predicate, )); } - [errors @ .., last] => { + _ => { diag.help(format!( "`Clone` is not implemented because the following trait bounds \ - could not be satisfied: {} and `{}`", - errors - .iter() - .map(|e| format!("`{}`", e.obligation.predicate)) - .collect::>() - .join(", "), - last.obligation.predicate, + could not be satisfied: {}", + listify(&errors, |e| format!("`{}`", e.obligation.predicate)) + .unwrap(), )); } } diff --git a/compiler/rustc_lint_defs/src/lib.rs b/compiler/rustc_lint_defs/src/lib.rs index 3f1e98556ef0c..7ffe4e4e4901c 100644 --- a/compiler/rustc_lint_defs/src/lib.rs +++ b/compiler/rustc_lint_defs/src/lib.rs @@ -42,6 +42,23 @@ macro_rules! pluralize { }; } +/// Grammatical tool for displaying messages to end users in a nice form. +/// +/// Take a list of items and a function to turn those items into a `String`, and output a display +/// friendly comma separated list of those items. +// FIXME(estebank): this needs to be changed to go through the translation machinery. +pub fn listify(list: &[T], fmt: impl Fn(&T) -> String) -> Option { + Some(match list { + [only] => fmt(&only), + [others @ .., last] => format!( + "{} and {}", + others.iter().map(|i| fmt(i)).collect::>().join(", "), + fmt(&last), + ), + [] => return None, + }) +} + /// Indicates the confidence in the correctness of a suggestion. /// /// All suggestions are marked with an `Applicability`. Tools use the applicability of a suggestion diff --git a/compiler/rustc_middle/src/ty/diagnostics.rs b/compiler/rustc_middle/src/ty/diagnostics.rs index b4b66a8133a33..cb218a27e6237 100644 --- a/compiler/rustc_middle/src/ty/diagnostics.rs +++ b/compiler/rustc_middle/src/ty/diagnostics.rs @@ -5,7 +5,7 @@ use std::ops::ControlFlow; use rustc_data_structures::fx::FxHashMap; use rustc_errors::{ - Applicability, Diag, DiagArgValue, IntoDiagArg, into_diag_arg_using_display, pluralize, + Applicability, Diag, DiagArgValue, IntoDiagArg, into_diag_arg_using_display, listify, pluralize, }; use rustc_hir::def::DefKind; use rustc_hir::def_id::DefId; @@ -362,11 +362,8 @@ pub fn suggest_constraining_type_params<'a>( let n = trait_names.len(); let stable = if all_stable { "" } else { "unstable " }; let trait_ = if all_known { format!("trait{}", pluralize!(n)) } else { String::new() }; - format!("{stable}{trait_}{}", match &trait_names[..] { - [t] => format!(" {t}"), - [ts @ .., last] => format!(" {} and {last}", ts.join(", ")), - [] => return false, - },) + let Some(trait_names) = listify(&trait_names, |n| n.to_string()) else { return false }; + format!("{stable}{trait_} {trait_names}") } else { // We're more explicit when there's a mix of stable and unstable traits. let mut trait_names = constraints @@ -378,10 +375,9 @@ pub fn suggest_constraining_type_params<'a>( .collect::>(); trait_names.sort(); trait_names.dedup(); - match &trait_names[..] { - [t] => t.to_string(), - [ts @ .., last] => format!("{} and {last}", ts.join(", ")), - [] => return false, + match listify(&trait_names, |t| t.to_string()) { + Some(names) => names, + None => return false, } }; let constraint = constraint.join(" + "); diff --git a/compiler/rustc_privacy/src/lib.rs b/compiler/rustc_privacy/src/lib.rs index d19df08519d26..3842b7035e537 100644 --- a/compiler/rustc_privacy/src/lib.rs +++ b/compiler/rustc_privacy/src/lib.rs @@ -24,7 +24,7 @@ use rustc_ast::MacroDef; use rustc_ast::visit::{VisitorResult, try_visit}; use rustc_data_structures::fx::FxHashSet; use rustc_data_structures::intern::Interned; -use rustc_errors::MultiSpan; +use rustc_errors::{MultiSpan, listify}; use rustc_hir::def::{DefKind, Res}; use rustc_hir::def_id::{CRATE_DEF_ID, DefId, LocalDefId, LocalModDefId}; use rustc_hir::intravisit::{self, InferKind, Visitor}; @@ -958,29 +958,15 @@ impl<'tcx> NamePrivacyVisitor<'tcx> { // | ^^ field `gamma` is private # `fields.2` is `false` // Get the list of all private fields for the main message. - let field_names: Vec<_> = fields.iter().map(|(name, _, _)| name).collect(); - let field_names = match &field_names[..] { - [] => return, - [name] => format!("`{name}`"), - [fields @ .., last] => format!( - "{} and `{last}`", - fields.iter().map(|f| format!("`{f}`")).collect::>().join(", "), - ), - }; + let Some(field_names) = listify(&fields[..], |(n, _, _)| format!("`{n}`")) else { return }; let span: MultiSpan = fields.iter().map(|(_, span, _)| *span).collect::>().into(); // Get the list of all private fields when pointing at the `..rest`. let rest_field_names: Vec<_> = fields.iter().filter(|(_, _, is_present)| !is_present).map(|(n, _, _)| n).collect(); let rest_len = rest_field_names.len(); - let rest_field_names = match &rest_field_names[..] { - [] => String::new(), - [name] => format!("`{name}`"), - [fields @ .., last] => format!( - "{} and `{last}`", - fields.iter().map(|f| format!("`{f}`")).collect::>().join(", "), - ), - }; + let rest_field_names = + listify(&rest_field_names[..], |n| format!("`{n}`")).unwrap_or_default(); // Get all the labels for each field or `..rest` in the primary MultiSpan. let labels = fields .iter() @@ -1005,7 +991,7 @@ impl<'tcx> NamePrivacyVisitor<'tcx> { } else { None }, - field_names: field_names.clone(), + field_names, variant_descr: def.variant_descr(), def_path_str: self.tcx.def_path_str(def.did()), labels,