diff --git a/src/librustc_front/print/pprust.rs b/src/librustc_front/print/pprust.rs index d4a52a5ed8eb0..940145aa4173b 100644 --- a/src/librustc_front/print/pprust.rs +++ b/src/librustc_front/print/pprust.rs @@ -1218,34 +1218,34 @@ impl<'a> State<'a> { fields: &[hir::Field], wth: &Option>) -> io::Result<()> { try!(self.print_path(path, true, 0)); - if !(fields.is_empty() && wth.is_none()) { - try!(word(&mut self.s, "{")); - try!(self.commasep_cmnt( - Consistent, - &fields[..], - |s, field| { - try!(s.ibox(indent_unit)); - try!(s.print_ident(field.ident.node)); - try!(s.word_space(":")); - try!(s.print_expr(&*field.expr)); - s.end() - }, - |f| f.span)); - match *wth { - Some(ref expr) => { - try!(self.ibox(indent_unit)); - if !fields.is_empty() { - try!(word(&mut self.s, ",")); - try!(space(&mut self.s)); - } - try!(word(&mut self.s, "..")); - try!(self.print_expr(&**expr)); - try!(self.end()); + try!(word(&mut self.s, "{")); + try!(self.commasep_cmnt( + Consistent, + &fields[..], + |s, field| { + try!(s.ibox(indent_unit)); + try!(s.print_ident(field.ident.node)); + try!(s.word_space(":")); + try!(s.print_expr(&*field.expr)); + s.end() + }, + |f| f.span)); + match *wth { + Some(ref expr) => { + try!(self.ibox(indent_unit)); + if !fields.is_empty() { + try!(word(&mut self.s, ",")); + try!(space(&mut self.s)); } - _ => try!(word(&mut self.s, ",")), + try!(word(&mut self.s, "..")); + try!(self.print_expr(&**expr)); + try!(self.end()); + } + _ => if !fields.is_empty() { + try!(word(&mut self.s, ",")) } - try!(word(&mut self.s, "}")); } + try!(word(&mut self.s, "}")); Ok(()) } diff --git a/src/librustc_typeck/check/mod.rs b/src/librustc_typeck/check/mod.rs index e5dbfdf176739..6f1e2e283e7a2 100644 --- a/src/librustc_typeck/check/mod.rs +++ b/src/librustc_typeck/check/mod.rs @@ -1473,14 +1473,14 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { _ => return None }; - if let ty::VariantKind::Dict = variant.kind() { + let var_kind = variant.kind(); + if var_kind == ty::VariantKind::Dict || var_kind == ty::VariantKind::Unit { Some((adt, variant)) } else { None } } - pub fn write_nil(&self, node_id: ast::NodeId) { self.write_ty(node_id, self.tcx().mk_nil()); } diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs index b6650b6f94420..a7978babcb7e1 100644 --- a/src/libsyntax/parse/parser.rs +++ b/src/libsyntax/parse/parser.rs @@ -2231,14 +2231,6 @@ impl<'a> Parser<'a> { &[token::CloseDelim(token::Brace)])); } - if fields.is_empty() && base.is_none() { - let last_span = self.last_span; - self.span_err(last_span, - "structure literal must either \ - have at least one field or use \ - structure update syntax"); - } - hi = self.span.hi; try!(self.expect(&token::CloseDelim(token::Brace))); ex = ExprStruct(pth, fields, base); @@ -4713,14 +4705,14 @@ impl<'a> Parser<'a> { (Vec::new(), Some(ast::DUMMY_NODE_ID)) } else { // If we see: `struct Foo where T: Copy { ... }` - (try!(self.parse_record_struct_body(&class_name)), None) + (try!(self.parse_record_struct_body()), None) } // No `where` so: `struct Foo;` } else if try!(self.eat(&token::Semi) ){ (Vec::new(), Some(ast::DUMMY_NODE_ID)) // Record-style struct definition } else if self.token == token::OpenDelim(token::Brace) { - let fields = try!(self.parse_record_struct_body(&class_name)); + let fields = try!(self.parse_record_struct_body()); (fields, None) // Tuple-style struct definition with optional where-clause. } else if self.token == token::OpenDelim(token::Paren) { @@ -4740,20 +4732,13 @@ impl<'a> Parser<'a> { None)) } - pub fn parse_record_struct_body(&mut self, - class_name: &ast::Ident) -> PResult> { + pub fn parse_record_struct_body(&mut self) -> PResult> { let mut fields = Vec::new(); if try!(self.eat(&token::OpenDelim(token::Brace)) ){ while self.token != token::CloseDelim(token::Brace) { fields.push(try!(self.parse_struct_decl_field(true))); } - if fields.is_empty() { - return Err(self.fatal(&format!("unit-like struct definition should be \ - written as `struct {};`", - class_name))); - } - try!(self.bump()); } else { let token_str = self.this_token_to_string(); diff --git a/src/libsyntax/print/pprust.rs b/src/libsyntax/print/pprust.rs index b00ff85051c9a..1d22c83122e51 100644 --- a/src/libsyntax/print/pprust.rs +++ b/src/libsyntax/print/pprust.rs @@ -1855,34 +1855,34 @@ impl<'a> State<'a> { fields: &[ast::Field], wth: &Option>) -> io::Result<()> { try!(self.print_path(path, true, 0)); - if !(fields.is_empty() && wth.is_none()) { - try!(word(&mut self.s, "{")); - try!(self.commasep_cmnt( - Consistent, - &fields[..], - |s, field| { - try!(s.ibox(indent_unit)); - try!(s.print_ident(field.ident.node)); - try!(s.word_space(":")); - try!(s.print_expr(&*field.expr)); - s.end() - }, - |f| f.span)); - match *wth { - Some(ref expr) => { - try!(self.ibox(indent_unit)); - if !fields.is_empty() { - try!(word(&mut self.s, ",")); - try!(space(&mut self.s)); - } - try!(word(&mut self.s, "..")); - try!(self.print_expr(&**expr)); - try!(self.end()); + try!(word(&mut self.s, "{")); + try!(self.commasep_cmnt( + Consistent, + &fields[..], + |s, field| { + try!(s.ibox(indent_unit)); + try!(s.print_ident(field.ident.node)); + try!(s.word_space(":")); + try!(s.print_expr(&*field.expr)); + s.end() + }, + |f| f.span)); + match *wth { + Some(ref expr) => { + try!(self.ibox(indent_unit)); + if !fields.is_empty() { + try!(word(&mut self.s, ",")); + try!(space(&mut self.s)); } - _ => try!(word(&mut self.s, ",")), + try!(word(&mut self.s, "..")); + try!(self.print_expr(&**expr)); + try!(self.end()); + } + _ => if !fields.is_empty() { + try!(word(&mut self.s, ",")) } - try!(word(&mut self.s, "}")); } + try!(word(&mut self.s, "}")); Ok(()) } diff --git a/src/test/parse-fail/struct-no-fields-2.rs b/src/test/compile-fail/empty-struct-with-braces-1.rs similarity index 62% rename from src/test/parse-fail/struct-no-fields-2.rs rename to src/test/compile-fail/empty-struct-with-braces-1.rs index 1e6169f285b5c..bfe72856a2e17 100644 --- a/src/test/parse-fail/struct-no-fields-2.rs +++ b/src/test/compile-fail/empty-struct-with-braces-1.rs @@ -1,4 +1,4 @@ -// Copyright 2013 The Rust Project Developers. See the COPYRIGHT +// Copyright 2015 The Rust Project Developers. See the COPYRIGHT // file at the top-level directory of this distribution and at // http://rust-lang.org/COPYRIGHT. // @@ -8,13 +8,10 @@ // option. This file may not be copied, modified, or distributed // except according to those terms. -// compile-flags: -Z parse-only +// Empty struct defined with braces shouldn't add names into value namespace -struct Foo; +struct Empty {} -fn f2() { - let _end_stmt = Foo { }; - //~^ ERROR: structure literal must either have at least one field +fn main() { + let e = Empty; //~ ERROR `Empty` is the name of a struct or struct variant } - -fn main() {} diff --git a/src/test/parse-fail/struct-no-fields-3.rs b/src/test/compile-fail/empty-struct-with-braces-2.rs similarity index 52% rename from src/test/parse-fail/struct-no-fields-3.rs rename to src/test/compile-fail/empty-struct-with-braces-2.rs index 8e72151ffe979..7e5a87fe1a44e 100644 --- a/src/test/parse-fail/struct-no-fields-3.rs +++ b/src/test/compile-fail/empty-struct-with-braces-2.rs @@ -1,4 +1,4 @@ -// Copyright 2013 The Rust Project Developers. See the COPYRIGHT +// Copyright 2015 The Rust Project Developers. See the COPYRIGHT // file at the top-level directory of this distribution and at // http://rust-lang.org/COPYRIGHT. // @@ -8,13 +8,17 @@ // option. This file may not be copied, modified, or distributed // except according to those terms. -// compile-flags: -Z parse-only +// Empty struct defined with braces shouldn't add names into value namespace -struct Foo; +#![deny(warnings)] -fn g3() { - let _mid_tuple = (Foo { }, 2); - //~^ ERROR: structure literal must either have at least one field -} +struct Empty {} + +fn main() { + let e = Empty {}; -fn main() {} + match e { + Empty => () //~ ERROR unused variable: `Empty` + //~^ ERROR variable `Empty` should have a snake case name such as `empty` + } +} diff --git a/src/test/compile-fail/issue-27831.rs b/src/test/compile-fail/issue-27831.rs index 336368cf8a49d..533387c576008 100644 --- a/src/test/compile-fail/issue-27831.rs +++ b/src/test/compile-fail/issue-27831.rs @@ -22,8 +22,8 @@ fn main() { let Foo { .. } = x; //~ ERROR `Foo` does not name a struct let x = Bar; - Bar { ..x }; //~ ERROR `Bar` does not name a structure - let Bar { .. } = x; //~ ERROR `Bar` does not name a struct + Bar { ..x }; + let Bar { .. } = x; match Enum::Bar { Enum::Bar { .. } //~ ERROR `Enum::Bar` does not name a struct diff --git a/src/test/parse-fail/struct-no-fields-4.rs b/src/test/parse-fail/struct-no-fields-4.rs deleted file mode 100644 index 6e55baf06cedf..0000000000000 --- a/src/test/parse-fail/struct-no-fields-4.rs +++ /dev/null @@ -1,20 +0,0 @@ -// Copyright 2013 The Rust Project Developers. See the COPYRIGHT -// file at the top-level directory of this distribution and at -// http://rust-lang.org/COPYRIGHT. -// -// Licensed under the Apache License, Version 2.0 or the MIT license -// , at your -// option. This file may not be copied, modified, or distributed -// except according to those terms. - -// compile-flags: -Z parse-only - -struct Foo; - -fn h4() { - let _end_of_tuple = (3, Foo { }); - //~^ ERROR: structure literal must either have at least one field -} - -fn main() {} diff --git a/src/test/parse-fail/struct-no-fields-5.rs b/src/test/parse-fail/struct-no-fields-5.rs deleted file mode 100644 index 5f92d98606693..0000000000000 --- a/src/test/parse-fail/struct-no-fields-5.rs +++ /dev/null @@ -1,20 +0,0 @@ -// Copyright 2013 The Rust Project Developers. See the COPYRIGHT -// file at the top-level directory of this distribution and at -// http://rust-lang.org/COPYRIGHT. -// -// Licensed under the Apache License, Version 2.0 or the MIT license -// , at your -// option. This file may not be copied, modified, or distributed -// except according to those terms. - -// compile-flags: -Z parse-only - -struct Foo; - -fn i5() { - let _end_of_block = { Foo { } }; - //~^ ERROR: structure literal must either have at least one field -} - -fn main() {} diff --git a/src/test/run-pass/empty-struct-with-braces.rs b/src/test/run-pass/empty-struct-with-braces.rs new file mode 100644 index 0000000000000..a96c1e5b10c4b --- /dev/null +++ b/src/test/run-pass/empty-struct-with-braces.rs @@ -0,0 +1,31 @@ +// Copyright 2015 The Rust Project Developers. See the COPYRIGHT +// file at the top-level directory of this distribution and at +// http://rust-lang.org/COPYRIGHT. +// +// Licensed under the Apache License, Version 2.0 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +// Empty struct defined with braces add names into type namespace +// Empty struct defined without braces add names into both type and value namespaces + +struct Empty1 {} +struct Empty2; + +fn main() { + let e1: Empty1 = Empty1 {}; + let e2: Empty2 = Empty2 {}; + let e2: Empty2 = Empty2; + + match e1 { + Empty1 {} => () + } + match e2 { + Empty2 {} => () + } + match e2 { + Empty2 => () + } +} diff --git a/src/test/parse-fail/struct-no-fields.rs b/src/test/run-pass/issue-16819.rs similarity index 67% rename from src/test/parse-fail/struct-no-fields.rs rename to src/test/run-pass/issue-16819.rs index fa5065b763027..fb35ce33157d6 100644 --- a/src/test/parse-fail/struct-no-fields.rs +++ b/src/test/run-pass/issue-16819.rs @@ -1,4 +1,4 @@ -// Copyright 2012 The Rust Project Developers. See the COPYRIGHT +// Copyright 2015 The Rust Project Developers. See the COPYRIGHT // file at the top-level directory of this distribution and at // http://rust-lang.org/COPYRIGHT. // @@ -8,9 +8,13 @@ // option. This file may not be copied, modified, or distributed // except according to those terms. -// compile-flags: -Z parse-only +//`#[cfg]` on struct field permits empty unusable struct -struct Foo {} -//~^ ERROR: unit-like struct definition should be written as `struct Foo;` +struct S { + #[cfg(untrue)] + a: int, +} -fn main() {} +fn main() { + let s = S {}; +}