From 2b8060578a4a7dafc74f782850c86762ec05857a Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Le=C3=B3n=20Orell=20Valerian=20Liehr?= Date: Mon, 19 Feb 2024 14:25:33 +0100 Subject: [PATCH] AST: Refactor type alias where clauses --- compiler/rustc_ast/src/ast.rs | 32 +++++++++++++------ compiler/rustc_ast/src/mut_visit.rs | 12 +++---- compiler/rustc_ast_lowering/src/item.rs | 19 +++++------ .../rustc_ast_passes/src/ast_validation.rs | 27 ++++++++-------- .../rustc_ast_pretty/src/pprust/state/item.rs | 15 +++------ .../src/deriving/generic/mod.rs | 6 +--- compiler/rustc_parse/src/parser/item.rs | 17 ++++++---- src/tools/rustfmt/src/items.rs | 30 ++++------------- 8 files changed, 73 insertions(+), 85 deletions(-) diff --git a/compiler/rustc_ast/src/ast.rs b/compiler/rustc_ast/src/ast.rs index 4ae18b4cf4854..31dd358ad51f4 100644 --- a/compiler/rustc_ast/src/ast.rs +++ b/compiler/rustc_ast/src/ast.rs @@ -403,9 +403,10 @@ impl Default for Generics { /// A where-clause in a definition. #[derive(Clone, Encodable, Decodable, Debug)] pub struct WhereClause { - /// `true` if we ate a `where` token: this can happen - /// if we parsed no predicates (e.g. `struct Foo where {}`). - /// This allows us to pretty-print accurately. + /// `true` if we ate a `where` token. + /// + /// This can happen if we parsed no predicates, e.g., `struct Foo where {}`. + /// This allows us to pretty-print accurately and provide correct suggestion diagnostics. pub has_where_token: bool, pub predicates: ThinVec, pub span: Span, @@ -3007,18 +3008,29 @@ pub struct Trait { /// /// If there is no where clause, then this is `false` with `DUMMY_SP`. #[derive(Copy, Clone, Encodable, Decodable, Debug, Default)] -pub struct TyAliasWhereClause(pub bool, pub Span); +pub struct TyAliasWhereClause { + pub has_where_token: bool, + pub span: Span, +} + +/// The span information for the two where clauses on a `TyAlias`. +#[derive(Copy, Clone, Encodable, Decodable, Debug, Default)] +pub struct TyAliasWhereClauses { + /// Before the equals sign. + pub before: TyAliasWhereClause, + /// After the equals sign. + pub after: TyAliasWhereClause, + /// The index in `TyAlias.generics.where_clause.predicates` that would split + /// into predicates from the where clause before the equals sign and the ones + /// from the where clause after the equals sign. + pub split: usize, +} #[derive(Clone, Encodable, Decodable, Debug)] pub struct TyAlias { pub defaultness: Defaultness, pub generics: Generics, - /// The span information for the two where clauses (before equals, after equals) - pub where_clauses: (TyAliasWhereClause, TyAliasWhereClause), - /// The index in `generics.where_clause.predicates` that would split into - /// predicates from the where clause before the equals and the predicates - /// from the where clause after the equals - pub where_predicates_split: usize, + pub where_clauses: TyAliasWhereClauses, pub bounds: GenericBounds, pub ty: Option>, } diff --git a/compiler/rustc_ast/src/mut_visit.rs b/compiler/rustc_ast/src/mut_visit.rs index 60bc21c6441fc..2faf3228d551e 100644 --- a/compiler/rustc_ast/src/mut_visit.rs +++ b/compiler/rustc_ast/src/mut_visit.rs @@ -1079,8 +1079,8 @@ pub fn noop_visit_item_kind(kind: &mut ItemKind, vis: &mut T) { }) => { visit_defaultness(defaultness, vis); vis.visit_generics(generics); - vis.visit_span(&mut where_clauses.0.1); - vis.visit_span(&mut where_clauses.1.1); + vis.visit_span(&mut where_clauses.before.span); + vis.visit_span(&mut where_clauses.after.span); visit_bounds(bounds, vis); visit_opt(ty, |ty| vis.visit_ty(ty)); } @@ -1163,8 +1163,8 @@ pub fn noop_flat_map_assoc_item( }) => { visit_defaultness(defaultness, visitor); visitor.visit_generics(generics); - visitor.visit_span(&mut where_clauses.0.1); - visitor.visit_span(&mut where_clauses.1.1); + visitor.visit_span(&mut where_clauses.before.span); + visitor.visit_span(&mut where_clauses.after.span); visit_bounds(bounds, visitor); visit_opt(ty, |ty| visitor.visit_ty(ty)); } @@ -1257,8 +1257,8 @@ pub fn noop_flat_map_foreign_item( }) => { visit_defaultness(defaultness, visitor); visitor.visit_generics(generics); - visitor.visit_span(&mut where_clauses.0.1); - visitor.visit_span(&mut where_clauses.1.1); + visitor.visit_span(&mut where_clauses.before.span); + visitor.visit_span(&mut where_clauses.after.span); visit_bounds(bounds, visitor); visit_opt(ty, |ty| visitor.visit_ty(ty)); } diff --git a/compiler/rustc_ast_lowering/src/item.rs b/compiler/rustc_ast_lowering/src/item.rs index 87ed47648c813..01b1e6fcaff64 100644 --- a/compiler/rustc_ast_lowering/src/item.rs +++ b/compiler/rustc_ast_lowering/src/item.rs @@ -33,19 +33,20 @@ pub(super) struct ItemLowerer<'a, 'hir> { /// clause if it exists. fn add_ty_alias_where_clause( generics: &mut ast::Generics, - mut where_clauses: (TyAliasWhereClause, TyAliasWhereClause), + mut where_clauses: TyAliasWhereClauses, prefer_first: bool, ) { if !prefer_first { - where_clauses = (where_clauses.1, where_clauses.0); - } - if where_clauses.0.0 || !where_clauses.1.0 { - generics.where_clause.has_where_token = where_clauses.0.0; - generics.where_clause.span = where_clauses.0.1; - } else { - generics.where_clause.has_where_token = where_clauses.1.0; - generics.where_clause.span = where_clauses.1.1; + (where_clauses.before, where_clauses.after) = (where_clauses.after, where_clauses.before); } + let where_clause = + if where_clauses.before.has_where_token || !where_clauses.after.has_where_token { + where_clauses.before + } else { + where_clauses.after + }; + generics.where_clause.has_where_token = where_clause.has_where_token; + generics.where_clause.span = where_clause.span; } impl<'a, 'hir> ItemLowerer<'a, 'hir> { diff --git a/compiler/rustc_ast_passes/src/ast_validation.rs b/compiler/rustc_ast_passes/src/ast_validation.rs index 8c9ad83608761..a53f83bbcdc9a 100644 --- a/compiler/rustc_ast_passes/src/ast_validation.rs +++ b/compiler/rustc_ast_passes/src/ast_validation.rs @@ -139,14 +139,14 @@ impl<'a> AstValidator<'a> { ty_alias: &TyAlias, ) -> Result<(), errors::WhereClauseBeforeTypeAlias> { let before_predicates = - ty_alias.generics.where_clause.predicates.split_at(ty_alias.where_predicates_split).0; + ty_alias.generics.where_clause.predicates.split_at(ty_alias.where_clauses.split).0; if ty_alias.ty.is_none() || before_predicates.is_empty() { return Ok(()); } let mut state = State::new(); - if !ty_alias.where_clauses.1.0 { + if !ty_alias.where_clauses.after.has_where_token { state.space(); state.word_space("where"); } else { @@ -161,13 +161,13 @@ impl<'a> AstValidator<'a> { state.print_where_predicate(p); } - let span = ty_alias.where_clauses.0.1; + let span = ty_alias.where_clauses.before.span; Err(errors::WhereClauseBeforeTypeAlias { span, sugg: errors::WhereClauseBeforeTypeAliasSugg { left: span, snippet: state.s.eof(), - right: ty_alias.where_clauses.1.1.shrink_to_hi(), + right: ty_alias.where_clauses.after.span.shrink_to_hi(), }, }) } @@ -457,8 +457,7 @@ impl<'a> AstValidator<'a> { fn check_foreign_ty_genericless( &self, generics: &Generics, - before_where_clause: &TyAliasWhereClause, - after_where_clause: &TyAliasWhereClause, + where_clauses: &TyAliasWhereClauses, ) { let cannot_have = |span, descr, remove_descr| { self.dcx().emit_err(errors::ExternTypesCannotHave { @@ -473,14 +472,14 @@ impl<'a> AstValidator<'a> { cannot_have(generics.span, "generic parameters", "generic parameters"); } - let check_where_clause = |where_clause: &TyAliasWhereClause| { - if let TyAliasWhereClause(true, where_clause_span) = where_clause { - cannot_have(*where_clause_span, "`where` clauses", "`where` clause"); + let check_where_clause = |where_clause: TyAliasWhereClause| { + if where_clause.has_where_token { + cannot_have(where_clause.span, "`where` clauses", "`where` clause"); } }; - check_where_clause(before_where_clause); - check_where_clause(after_where_clause); + check_where_clause(where_clauses.before); + check_where_clause(where_clauses.after); } fn check_foreign_kind_bodyless(&self, ident: Ident, kind: &str, body: Option) { @@ -1122,9 +1121,9 @@ impl<'a> Visitor<'a> for AstValidator<'a> { if let Err(err) = self.check_type_alias_where_clause_location(ty_alias) { self.dcx().emit_err(err); } - } else if where_clauses.1.0 { + } else if where_clauses.after.has_where_token { self.dcx().emit_err(errors::WhereClauseAfterTypeAlias { - span: where_clauses.1.1, + span: where_clauses.after.span, help: self.session.is_nightly_build().then_some(()), }); } @@ -1154,7 +1153,7 @@ impl<'a> Visitor<'a> for AstValidator<'a> { self.check_defaultness(fi.span, *defaultness); self.check_foreign_kind_bodyless(fi.ident, "type", ty.as_ref().map(|b| b.span)); self.check_type_no_bounds(bounds, "`extern` blocks"); - self.check_foreign_ty_genericless(generics, &where_clauses.0, &where_clauses.1); + self.check_foreign_ty_genericless(generics, where_clauses); self.check_foreign_item_ascii_only(fi.ident); } ForeignItemKind::Static(_, _, body) => { diff --git a/compiler/rustc_ast_pretty/src/pprust/state/item.rs b/compiler/rustc_ast_pretty/src/pprust/state/item.rs index 584f01e16c2c3..13f27c1c95c2e 100644 --- a/compiler/rustc_ast_pretty/src/pprust/state/item.rs +++ b/compiler/rustc_ast_pretty/src/pprust/state/item.rs @@ -43,7 +43,6 @@ impl<'a> State<'a> { defaultness, generics, where_clauses, - where_predicates_split, bounds, ty, }) => { @@ -51,7 +50,6 @@ impl<'a> State<'a> { ident, generics, *where_clauses, - *where_predicates_split, bounds, ty.as_deref(), vis, @@ -108,15 +106,14 @@ impl<'a> State<'a> { &mut self, ident: Ident, generics: &ast::Generics, - where_clauses: (ast::TyAliasWhereClause, ast::TyAliasWhereClause), - where_predicates_split: usize, + where_clauses: ast::TyAliasWhereClauses, bounds: &ast::GenericBounds, ty: Option<&ast::Ty>, vis: &ast::Visibility, defaultness: ast::Defaultness, ) { let (before_predicates, after_predicates) = - generics.where_clause.predicates.split_at(where_predicates_split); + generics.where_clause.predicates.split_at(where_clauses.split); self.head(""); self.print_visibility(vis); self.print_defaultness(defaultness); @@ -127,13 +124,13 @@ impl<'a> State<'a> { self.word_nbsp(":"); self.print_type_bounds(bounds); } - self.print_where_clause_parts(where_clauses.0.0, before_predicates); + self.print_where_clause_parts(where_clauses.before.has_where_token, before_predicates); if let Some(ty) = ty { self.space(); self.word_space("="); self.print_type(ty); } - self.print_where_clause_parts(where_clauses.1.0, after_predicates); + self.print_where_clause_parts(where_clauses.after.has_where_token, after_predicates); self.word(";"); self.end(); // end inner head-block self.end(); // end outer head-block @@ -249,7 +246,6 @@ impl<'a> State<'a> { defaultness, generics, where_clauses, - where_predicates_split, bounds, ty, }) => { @@ -257,7 +253,6 @@ impl<'a> State<'a> { item.ident, generics, *where_clauses, - *where_predicates_split, bounds, ty.as_deref(), &item.vis, @@ -536,7 +531,6 @@ impl<'a> State<'a> { defaultness, generics, where_clauses, - where_predicates_split, bounds, ty, }) => { @@ -544,7 +538,6 @@ impl<'a> State<'a> { ident, generics, *where_clauses, - *where_predicates_split, bounds, ty.as_deref(), vis, diff --git a/compiler/rustc_builtin_macros/src/deriving/generic/mod.rs b/compiler/rustc_builtin_macros/src/deriving/generic/mod.rs index 3ee4fded74999..eb664b571ba85 100644 --- a/compiler/rustc_builtin_macros/src/deriving/generic/mod.rs +++ b/compiler/rustc_builtin_macros/src/deriving/generic/mod.rs @@ -601,11 +601,7 @@ impl<'a> TraitDef<'a> { kind: ast::AssocItemKind::Type(Box::new(ast::TyAlias { defaultness: ast::Defaultness::Final, generics: Generics::default(), - where_clauses: ( - ast::TyAliasWhereClause::default(), - ast::TyAliasWhereClause::default(), - ), - where_predicates_split: 0, + where_clauses: ast::TyAliasWhereClauses::default(), bounds: Vec::new(), ty: Some(type_def.to_ty(cx, self.span, type_ident, generics)), })), diff --git a/compiler/rustc_parse/src/parser/item.rs b/compiler/rustc_parse/src/parser/item.rs index a678194372e9b..d8587f1340a1a 100644 --- a/compiler/rustc_parse/src/parser/item.rs +++ b/compiler/rustc_parse/src/parser/item.rs @@ -971,11 +971,17 @@ impl<'a> Parser<'a> { let after_where_clause = self.parse_where_clause()?; - let where_clauses = ( - TyAliasWhereClause(before_where_clause.has_where_token, before_where_clause.span), - TyAliasWhereClause(after_where_clause.has_where_token, after_where_clause.span), - ); - let where_predicates_split = before_where_clause.predicates.len(); + let where_clauses = TyAliasWhereClauses { + before: TyAliasWhereClause { + has_where_token: before_where_clause.has_where_token, + span: before_where_clause.span, + }, + after: TyAliasWhereClause { + has_where_token: after_where_clause.has_where_token, + span: after_where_clause.span, + }, + split: before_where_clause.predicates.len(), + }; let mut predicates = before_where_clause.predicates; predicates.extend(after_where_clause.predicates); let where_clause = WhereClause { @@ -994,7 +1000,6 @@ impl<'a> Parser<'a> { defaultness, generics, where_clauses, - where_predicates_split, bounds, ty, })), diff --git a/src/tools/rustfmt/src/items.rs b/src/tools/rustfmt/src/items.rs index b57be8c10549e..f6f51fbd8eaf9 100644 --- a/src/tools/rustfmt/src/items.rs +++ b/src/tools/rustfmt/src/items.rs @@ -1651,8 +1651,7 @@ struct TyAliasRewriteInfo<'c, 'g>( &'c RewriteContext<'c>, Indent, &'g ast::Generics, - (ast::TyAliasWhereClause, ast::TyAliasWhereClause), - usize, + ast::TyAliasWhereClauses, symbol::Ident, Span, ); @@ -1672,7 +1671,6 @@ pub(crate) fn rewrite_type_alias<'a, 'b>( ref bounds, ref ty, where_clauses, - where_predicates_split, } = *ty_alias_kind; let ty_opt = ty.as_ref(); let (ident, vis) = match visitor_kind { @@ -1680,15 +1678,7 @@ pub(crate) fn rewrite_type_alias<'a, 'b>( AssocTraitItem(i) | AssocImplItem(i) => (i.ident, &i.vis), ForeignItem(i) => (i.ident, &i.vis), }; - let rw_info = &TyAliasRewriteInfo( - context, - indent, - generics, - where_clauses, - where_predicates_split, - ident, - span, - ); + let rw_info = &TyAliasRewriteInfo(context, indent, generics, where_clauses, ident, span); let op_ty = opaque_ty(ty); // Type Aliases are formatted slightly differently depending on the context // in which they appear, whether they are opaque, and whether they are associated. @@ -1724,19 +1714,11 @@ fn rewrite_ty( vis: &ast::Visibility, ) -> Option { let mut result = String::with_capacity(128); - let TyAliasRewriteInfo( - context, - indent, - generics, - where_clauses, - where_predicates_split, - ident, - span, - ) = *rw_info; + let TyAliasRewriteInfo(context, indent, generics, where_clauses, ident, span) = *rw_info; let (before_where_predicates, after_where_predicates) = generics .where_clause .predicates - .split_at(where_predicates_split); + .split_at(where_clauses.split); if !after_where_predicates.is_empty() { return None; } @@ -1771,7 +1753,7 @@ fn rewrite_ty( let where_clause_str = rewrite_where_clause( context, before_where_predicates, - where_clauses.0.1, + where_clauses.before.span, context.config.brace_style(), Shape::legacy(where_budget, indent), false, @@ -1795,7 +1777,7 @@ fn rewrite_ty( let comment_span = context .snippet_provider .opt_span_before(span, "=") - .map(|op_lo| mk_sp(where_clauses.0.1.hi(), op_lo)); + .map(|op_lo| mk_sp(where_clauses.before.span.hi(), op_lo)); let lhs = match comment_span { Some(comment_span)