diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/libsyntax/parse/parser/item.rs | 28 | ||||
| -rw-r--r-- | src/test/ui/traits/trait-alias/trait-alias-syntax-fail.rs | 3 | ||||
| -rw-r--r-- | src/test/ui/traits/trait-alias/trait-alias-syntax-fail.stderr | 22 |
3 files changed, 40 insertions, 13 deletions
diff --git a/src/libsyntax/parse/parser/item.rs b/src/libsyntax/parse/parser/item.rs index 73bd80e2a21..01dc0c21d4d 100644 --- a/src/libsyntax/parse/parser/item.rs +++ b/src/libsyntax/parse/parser/item.rs @@ -211,7 +211,7 @@ impl<'a> Parser<'a> { { // UNSAFE TRAIT ITEM self.bump(); // `unsafe` - let info = self.parse_item_trait(Unsafety::Unsafe)?; + let info = self.parse_item_trait(lo, Unsafety::Unsafe)?; return self.mk_item_with_info(attrs, lo, vis, info); } @@ -289,7 +289,7 @@ impl<'a> Parser<'a> { && self.is_keyword_ahead(1, &[kw::Trait])) { // TRAIT ITEM - let info = self.parse_item_trait(Unsafety::Normal)?; + let info = self.parse_item_trait(lo, Unsafety::Normal)?; return self.mk_item_with_info(attrs, lo, vis, info); } @@ -780,7 +780,7 @@ impl<'a> Parser<'a> { } /// Parses `auto? trait Foo { ... }` or `trait Foo = Bar;`. - fn parse_item_trait(&mut self, unsafety: Unsafety) -> PResult<'a, ItemInfo> { + fn parse_item_trait(&mut self, lo: Span, unsafety: Unsafety) -> PResult<'a, ItemInfo> { // Parse optional `auto` prefix. let is_auto = if self.eat_keyword(kw::Auto) { IsAuto::Yes @@ -793,29 +793,41 @@ impl<'a> Parser<'a> { let mut tps = self.parse_generics()?; // Parse optional colon and supertrait bounds. - let bounds = if self.eat(&token::Colon) { + let had_colon = self.eat(&token::Colon); + let span_at_colon = self.prev_span; + let bounds = if had_colon { self.parse_generic_bounds(Some(self.prev_span))? } else { Vec::new() }; + let span_before_eq = self.prev_span; if self.eat(&token::Eq) { // It's a trait alias. + if had_colon { + let span = span_at_colon.to(span_before_eq); + self.struct_span_err(span, "bounds are not allowed on trait aliases") + .emit(); + } + let bounds = self.parse_generic_bounds(None)?; tps.where_clause = self.parse_where_clause()?; self.expect(&token::Semi)?; + + let whole_span = lo.to(self.prev_span); if is_auto == IsAuto::Yes { let msg = "trait aliases cannot be `auto`"; - self.struct_span_err(self.prev_span, msg) - .span_label(self.prev_span, msg) + self.struct_span_err(whole_span, msg) + .span_label(whole_span, msg) .emit(); } if unsafety != Unsafety::Normal { let msg = "trait aliases cannot be `unsafe`"; - self.struct_span_err(self.prev_span, msg) - .span_label(self.prev_span, msg) + self.struct_span_err(whole_span, msg) + .span_label(whole_span, msg) .emit(); } + Ok((ident, ItemKind::TraitAlias(tps, bounds), None)) } else { // It's a normal trait. diff --git a/src/test/ui/traits/trait-alias/trait-alias-syntax-fail.rs b/src/test/ui/traits/trait-alias/trait-alias-syntax-fail.rs index 5948d45b698..039bbce8c1e 100644 --- a/src/test/ui/traits/trait-alias/trait-alias-syntax-fail.rs +++ b/src/test/ui/traits/trait-alias/trait-alias-syntax-fail.rs @@ -4,4 +4,7 @@ trait Foo {} auto trait A = Foo; //~ ERROR trait aliases cannot be `auto` unsafe trait B = Foo; //~ ERROR trait aliases cannot be `unsafe` +trait C: Ord = Eq; //~ ERROR bounds are not allowed on trait aliases +trait D: = Eq; //~ ERROR bounds are not allowed on trait aliases + fn main() {} diff --git a/src/test/ui/traits/trait-alias/trait-alias-syntax-fail.stderr b/src/test/ui/traits/trait-alias/trait-alias-syntax-fail.stderr index f456a2d778c..18c22133bc7 100644 --- a/src/test/ui/traits/trait-alias/trait-alias-syntax-fail.stderr +++ b/src/test/ui/traits/trait-alias/trait-alias-syntax-fail.stderr @@ -1,14 +1,26 @@ error: trait aliases cannot be `auto` - --> $DIR/trait-alias-syntax-fail.rs:4:19 + --> $DIR/trait-alias-syntax-fail.rs:4:1 | LL | auto trait A = Foo; - | ^ trait aliases cannot be `auto` + | ^^^^^^^^^^^^^^^^^^^ trait aliases cannot be `auto` error: trait aliases cannot be `unsafe` - --> $DIR/trait-alias-syntax-fail.rs:5:21 + --> $DIR/trait-alias-syntax-fail.rs:5:1 | LL | unsafe trait B = Foo; - | ^ trait aliases cannot be `unsafe` + | ^^^^^^^^^^^^^^^^^^^^^ trait aliases cannot be `unsafe` -error: aborting due to 2 previous errors +error: bounds are not allowed on trait aliases + --> $DIR/trait-alias-syntax-fail.rs:7:8 + | +LL | trait C: Ord = Eq; + | ^^^^^ + +error: bounds are not allowed on trait aliases + --> $DIR/trait-alias-syntax-fail.rs:8:8 + | +LL | trait D: = Eq; + | ^ + +error: aborting due to 4 previous errors |