minor: Simplify impl-ty parse validation

This commit is contained in:
Lukas Wirth 2025-03-25 09:58:17 +01:00
parent 749fde9017
commit 389323ca09
4 changed files with 75 additions and 56 deletions

View file

@ -4,6 +4,7 @@
mod block;
use itertools::Itertools;
use rowan::Direction;
use rustc_lexer::unescape::{self, Mode, unescape_mixed, unescape_unicode};
@ -37,7 +38,8 @@ pub(crate) fn validate(root: &SyntaxNode, errors: &mut Vec<SyntaxError>) {
ast::FnPtrType(it) => validate_trait_object_fn_ptr_ret_ty(it, errors),
ast::MacroRules(it) => validate_macro_rules(it, errors),
ast::LetExpr(it) => validate_let_expr(it, errors),
ast::ImplTraitType(it) => validate_impl_object_ty(it, errors),
ast::DynTraitType(it) => errors.extend(validate_trait_object_ty(it)),
ast::ImplTraitType(it) => errors.extend(validate_impl_object_ty(it)),
_ => (),
}
}
@ -316,87 +318,104 @@ fn validate_path_keywords(segment: ast::PathSegment, errors: &mut Vec<SyntaxErro
}
fn validate_trait_object_ref_ty(ty: ast::RefType, errors: &mut Vec<SyntaxError>) {
if let Some(ast::Type::DynTraitType(ty)) = ty.ty() {
if let Some(err) = validate_trait_object_ty(ty) {
errors.push(err);
match ty.ty() {
Some(ast::Type::DynTraitType(ty)) => {
if let Some(err) = validate_trait_object_ty_plus(ty) {
errors.push(err);
}
}
Some(ast::Type::ImplTraitType(ty)) => {
if let Some(err) = validate_impl_object_ty_plus(ty) {
errors.push(err);
}
}
_ => (),
}
}
fn validate_trait_object_ptr_ty(ty: ast::PtrType, errors: &mut Vec<SyntaxError>) {
if let Some(ast::Type::DynTraitType(ty)) = ty.ty() {
if let Some(err) = validate_trait_object_ty(ty) {
errors.push(err);
match ty.ty() {
Some(ast::Type::DynTraitType(ty)) => {
if let Some(err) = validate_trait_object_ty_plus(ty) {
errors.push(err);
}
}
Some(ast::Type::ImplTraitType(ty)) => {
if let Some(err) = validate_impl_object_ty_plus(ty) {
errors.push(err);
}
}
_ => (),
}
}
fn validate_trait_object_fn_ptr_ret_ty(ty: ast::FnPtrType, errors: &mut Vec<SyntaxError>) {
if let Some(ast::Type::DynTraitType(ty)) = ty.ret_type().and_then(|ty| ty.ty()) {
if let Some(err) = validate_trait_object_ty(ty) {
errors.push(err);
match ty.ret_type().and_then(|ty| ty.ty()) {
Some(ast::Type::DynTraitType(ty)) => {
if let Some(err) = validate_trait_object_ty_plus(ty) {
errors.push(err);
}
}
Some(ast::Type::ImplTraitType(ty)) => {
if let Some(err) = validate_impl_object_ty_plus(ty) {
errors.push(err);
}
}
_ => (),
}
}
fn validate_trait_object_ty(ty: ast::DynTraitType) -> Option<SyntaxError> {
let tbl = ty.type_bound_list()?;
let bounds_count = tbl.bounds().count();
let no_bounds = tbl.bounds().filter_map(|it| it.ty()).next().is_none();
match bounds_count {
0 => Some(SyntaxError::new(
match no_bounds {
true => Some(SyntaxError::new(
"At least one trait is required for an object type",
ty.syntax().text_range(),
)),
_ if bounds_count > 1 => {
let dyn_token = ty.dyn_token()?;
let preceding_token =
algo::skip_trivia_token(dyn_token.prev_token()?, Direction::Prev)?;
if !matches!(preceding_token.kind(), T!['('] | T![<] | T![=]) {
return Some(SyntaxError::new("ambiguous `+` in a type", ty.syntax().text_range()));
}
None
}
_ => None,
false => None,
}
}
fn validate_impl_object_ty(ty: ast::ImplTraitType, errors: &mut Vec<SyntaxError>) {
let Some(bound_list) = ty.type_bound_list() else {
errors.push(SyntaxError::new(
"At least one trait must be specified",
fn validate_impl_object_ty(ty: ast::ImplTraitType) -> Option<SyntaxError> {
let tbl = ty.type_bound_list()?;
let no_bounds = tbl.bounds().filter_map(|it| it.ty()).next().is_none();
match no_bounds {
true => Some(SyntaxError::new(
"At least one trait is required for an object type",
ty.syntax().text_range(),
));
return;
};
let bounds: Vec<_> = bound_list.bounds().collect();
if !bounds.iter().any(|b| !matches!(b.kind(), ast::TypeBoundKind::Lifetime(_))) {
errors.push(SyntaxError::new(
"At least one trait must be specified",
ty.syntax().text_range(),
));
return;
)),
false => None,
}
}
if bounds.len() == 1 {
return;
// FIXME: This is not a validation error, this is a context dependent parse error
fn validate_trait_object_ty_plus(ty: ast::DynTraitType) -> Option<SyntaxError> {
let dyn_token = ty.dyn_token()?;
let preceding_token = algo::skip_trivia_token(dyn_token.prev_token()?, Direction::Prev)?;
let tbl = ty.type_bound_list()?;
let more_than_one_bound = tbl.bounds().next_tuple::<(_, _)>().is_some();
if more_than_one_bound && !matches!(preceding_token.kind(), T!['('] | T![<] | T![=]) {
Some(SyntaxError::new("ambiguous `+` in a type", ty.syntax().text_range()))
} else {
None
}
}
let Some(preceding_token) = ty
.impl_token()
.and_then(|token| token.prev_token())
.and_then(|prev| algo::skip_trivia_token(prev, Direction::Prev))
else {
return;
};
// FIXME: This is not a validation error, this is a context dependent parse error
fn validate_impl_object_ty_plus(ty: ast::ImplTraitType) -> Option<SyntaxError> {
let dyn_token = ty.impl_token()?;
let preceding_token = algo::skip_trivia_token(dyn_token.prev_token()?, Direction::Prev)?;
let tbl = ty.type_bound_list()?;
let more_than_one_bound = tbl.bounds().next_tuple::<(_, _)>().is_some();
if !matches!(preceding_token.kind(), T!['('] | T![<] | T![=])
&& matches!(preceding_token.kind(), T![&])
{
errors.push(SyntaxError::new("ambiguous `+` in a type", ty.syntax().text_range()));
if more_than_one_bound && !matches!(preceding_token.kind(), T!['('] | T![<] | T![=]) {
Some(SyntaxError::new("ambiguous `+` in a type", ty.syntax().text_range()))
} else {
None
}
}

View file

@ -20,4 +20,4 @@ SOURCE_FILE@0..16
STMT_LIST@14..16
L_CURLY@14..15 "{"
R_CURLY@15..16 "}"
error 8..12: At least one trait must be specified
error 8..12: At least one trait is required for an object type

View file

@ -22,4 +22,4 @@ SOURCE_FILE@0..17
STMT_LIST@15..17
L_CURLY@15..16 "{"
R_CURLY@16..17 "}"
error 9..13: At least one trait must be specified
error 9..13: At least one trait is required for an object type

View file

@ -26,4 +26,4 @@ SOURCE_FILE@0..20
STMT_LIST@18..20
L_CURLY@18..19 "{"
R_CURLY@19..20 "}"
error 9..16: At least one trait must be specified
error 9..16: At least one trait is required for an object type