From 63ee3fe566762781d1e60f190014b416f99fed36 Mon Sep 17 00:00:00 2001
From: Keegan McAllister <kmcallister@mozilla.com>
Date: Fri, 6 Mar 2015 12:56:28 -0800
Subject: [PATCH 1/3] Consolidate ExpansionConfig feature tests
---
src/libsyntax/ext/expand.rs | 60 +++++++++++++------------------------
1 file changed, 20 insertions(+), 40 deletions(-)
diff --git a/src/libsyntax/ext/expand.rs b/src/libsyntax/ext/expand.rs
index d48108f17ff9a..84b0299925211 100644
--- a/src/libsyntax/ext/expand.rs
+++ b/src/libsyntax/ext/expand.rs
@@ -1447,6 +1447,19 @@ pub struct ExpansionConfig<'feat> {
pub recursion_limit: usize,
}
+macro_rules! feature_tests {
+ ($( fn $getter:ident = $field:ident, )*) => {
+ $(
+ pub fn $getter(&self) -> bool {
+ match self.features {
+ Some(&Features { $field: true, .. }) => true,
+ _ => false,
+ }
+ }
+ )*
+ }
+}
+
impl<'feat> ExpansionConfig<'feat> {
pub fn default(crate_name: String) -> ExpansionConfig<'static> {
ExpansionConfig {
@@ -1456,46 +1469,13 @@ impl<'feat> ExpansionConfig<'feat> {
}
}
- pub fn enable_quotes(&self) -> bool {
- match self.features {
- Some(&Features { allow_quote: true, .. }) => true,
- _ => false,
- }
- }
-
- pub fn enable_asm(&self) -> bool {
- match self.features {
- Some(&Features { allow_asm: true, .. }) => true,
- _ => false,
- }
- }
-
- pub fn enable_log_syntax(&self) -> bool {
- match self.features {
- Some(&Features { allow_log_syntax: true, .. }) => true,
- _ => false,
- }
- }
-
- pub fn enable_concat_idents(&self) -> bool {
- match self.features {
- Some(&Features { allow_concat_idents: true, .. }) => true,
- _ => false,
- }
- }
-
- pub fn enable_trace_macros(&self) -> bool {
- match self.features {
- Some(&Features { allow_trace_macros: true, .. }) => true,
- _ => false,
- }
- }
-
- pub fn enable_allow_internal_unstable(&self) -> bool {
- match self.features {
- Some(&Features { allow_internal_unstable: true, .. }) => true,
- _ => false
- }
+ feature_tests! {
+ fn enable_quotes = allow_quote,
+ fn enable_asm = allow_asm,
+ fn enable_log_syntax = allow_log_syntax,
+ fn enable_concat_idents = allow_concat_idents,
+ fn enable_trace_macros = allow_trace_macros,
+ fn enable_allow_internal_unstable = allow_internal_unstable,
}
}
From e60e6f0693adfd03340dff31023c7517dc3af1b5 Mon Sep 17 00:00:00 2001
From: Keegan McAllister <kmcallister@mozilla.com>
Date: Fri, 6 Mar 2015 15:10:20 -0800
Subject: [PATCH 2/3] Check gated attributes before and after macro expansion
This is important because attributes can affect expansion.
---
src/libsyntax/feature_gate.rs | 75 ++++++++++---------
src/test/compile-fail/deprecated-phase.rs | 2 +
...ng-items.rs => feature-gate-intrinsics.rs} | 4 -
.../compile-fail/feature-gate-lang-items.rs | 15 ++++
src/test/compile-fail/linkage1.rs | 1 -
src/test/compile-fail/malformed-plugin-1.rs | 1 +
src/test/compile-fail/malformed-plugin-2.rs | 1 +
src/test/compile-fail/malformed-plugin-3.rs | 1 +
.../plugin-extern-crate-attr-deprecated.rs | 2 +
.../compile-fail/reserved-attr-on-macro.rs | 18 +++++
src/test/run-pass-fulldeps/macro-crate.rs | 2 +-
11 files changed, 79 insertions(+), 43 deletions(-)
rename src/test/compile-fail/{feature-gate-intrinsics-and-lang-items.rs => feature-gate-intrinsics.rs} (89%)
create mode 100644 src/test/compile-fail/feature-gate-lang-items.rs
create mode 100644 src/test/compile-fail/reserved-attr-on-macro.rs
diff --git a/src/libsyntax/feature_gate.rs b/src/libsyntax/feature_gate.rs
index c6a94b26a0a51..eff86757fd0b2 100644
--- a/src/libsyntax/feature_gate.rs
+++ b/src/libsyntax/feature_gate.rs
@@ -196,6 +196,7 @@ pub const KNOWN_ATTRIBUTES: &'static [(&'static str, AttributeType)] = &[
("no_mangle", Normal),
("no_link", Normal),
("derive", Normal),
+ ("deriving", Normal), // deprecation err in expansion
("should_fail", Normal),
("should_panic", Normal),
("ignore", Normal),
@@ -235,6 +236,9 @@ pub const KNOWN_ATTRIBUTES: &'static [(&'static str, AttributeType)] = &[
"the `#[rustc_move_fragments]` attribute \
is an experimental feature")),
+ ("allow_internal_unstable", Gated("allow_internal_unstable",
+ EXPLAIN_ALLOW_INTERNAL_UNSTABLE)),
+
// FIXME: #14408 whitelist docs since rustdoc looks at them
("doc", Whitelisted),
@@ -369,6 +373,33 @@ impl<'a> Context<'a> {
fn has_feature(&self, feature: &str) -> bool {
self.features.iter().any(|&n| n == feature)
}
+
+ fn check_attribute(&self, attr: &ast::Attribute) {
+ debug!("check_attribute(attr = {:?})", attr);
+ let name = &*attr.name();
+ for &(n, ty) in KNOWN_ATTRIBUTES {
+ if n == name {
+ if let Gated(gate, desc) = ty {
+ self.gate_feature(gate, attr.span, desc);
+ }
+ debug!("check_attribute: {:?} is known, {:?}", name, ty);
+ return;
+ }
+ }
+ if name.starts_with("rustc_") {
+ self.gate_feature("rustc_attrs", attr.span,
+ "unless otherwise specified, attributes \
+ with the prefix `rustc_` \
+ are reserved for internal compiler diagnostics");
+ } else {
+ self.gate_feature("custom_attribute", attr.span,
+ format!("The attribute `{}` is currently \
+ unknown to the the compiler and \
+ may have meaning \
+ added to it in the future",
+ name).as_slice());
+ }
+ }
}
pub fn emit_feature_err(diag: &SpanHandler, feature: &str, span: Span, explain: &str) {
@@ -436,10 +467,7 @@ impl<'a, 'v> Visitor<'v> for MacroVisitor<'a> {
}
fn visit_attribute(&mut self, attr: &'v ast::Attribute) {
- if attr.name() == "allow_internal_unstable" {
- self.context.gate_feature("allow_internal_unstable", attr.span,
- EXPLAIN_ALLOW_INTERNAL_UNSTABLE)
- }
+ self.context.check_attribute(attr);
}
}
@@ -456,6 +484,12 @@ impl<'a> PostExpansionVisitor<'a> {
}
impl<'a, 'v> Visitor<'v> for PostExpansionVisitor<'a> {
+ fn visit_attribute(&mut self, attr: &ast::Attribute) {
+ if !self.context.cm.span_allows_unstable(attr.span) {
+ self.context.check_attribute(attr);
+ }
+ }
+
fn visit_name(&mut self, sp: Span, name: ast::Name) {
if !token::get_name(name).is_ascii() {
self.gate_feature("non_ascii_idents", sp,
@@ -556,12 +590,6 @@ impl<'a, 'v> Visitor<'v> for PostExpansionVisitor<'a> {
}
fn visit_foreign_item(&mut self, i: &ast::ForeignItem) {
- if attr::contains_name(&i.attrs, "linkage") {
- self.gate_feature("linkage", i.span,
- "the `linkage` attribute is experimental \
- and not portable across platforms")
- }
-
let links_to_llvm = match attr::first_attr_value_str_by_name(&i.attrs,
"link_name") {
Some(val) => val.starts_with("llvm."),
@@ -636,33 +664,6 @@ impl<'a, 'v> Visitor<'v> for PostExpansionVisitor<'a> {
visit::walk_expr(self, e);
}
- fn visit_attribute(&mut self, attr: &ast::Attribute) {
- debug!("visit_attribute(attr = {:?})", attr);
- let name = &*attr.name();
- for &(n, ty) in KNOWN_ATTRIBUTES {
- if n == name {
- if let Gated(gate, desc) = ty {
- self.gate_feature(gate, attr.span, desc);
- }
- debug!("visit_attribute: {:?} is known, {:?}", name, ty);
- return;
- }
- }
- if name.starts_with("rustc_") {
- self.gate_feature("rustc_attrs", attr.span,
- "unless otherwise specified, attributes \
- with the prefix `rustc_` \
- are reserved for internal compiler diagnostics");
- } else {
- self.gate_feature("custom_attribute", attr.span,
- format!("The attribute `{}` is currently \
- unknown to the the compiler and \
- may have meaning \
- added to it in the future",
- name).as_slice());
- }
- }
-
fn visit_pat(&mut self, pattern: &ast::Pat) {
match pattern.node {
ast::PatVec(_, Some(_), ref last) if !last.is_empty() => {
diff --git a/src/test/compile-fail/deprecated-phase.rs b/src/test/compile-fail/deprecated-phase.rs
index 1401494d987a2..22fc4a94cd25a 100644
--- a/src/test/compile-fail/deprecated-phase.rs
+++ b/src/test/compile-fail/deprecated-phase.rs
@@ -8,6 +8,8 @@
// option. This file may not be copied, modified, or distributed
// except according to those terms.
+#![feature(custom_attribute)]
+
#[phase(blah)]
//~^ ERROR #[phase] is deprecated
extern crate foo;
diff --git a/src/test/compile-fail/feature-gate-intrinsics-and-lang-items.rs b/src/test/compile-fail/feature-gate-intrinsics.rs
similarity index 89%
rename from src/test/compile-fail/feature-gate-intrinsics-and-lang-items.rs
rename to src/test/compile-fail/feature-gate-intrinsics.rs
index 986d52b1787ec..a4c09b21c90a6 100644
--- a/src/test/compile-fail/feature-gate-intrinsics-and-lang-items.rs
+++ b/src/test/compile-fail/feature-gate-intrinsics.rs
@@ -8,9 +8,6 @@
// option. This file may not be copied, modified, or distributed
// except according to those terms.
-#[lang="foo"] //~ ERROR language items are subject to change
-trait Foo {}
-
extern "rust-intrinsic" { //~ ERROR intrinsics are subject to change
fn bar();
}
@@ -20,4 +17,3 @@ extern "rust-intrinsic" fn baz() { //~ ERROR intrinsics are subject to change
fn main() {
}
-
diff --git a/src/test/compile-fail/feature-gate-lang-items.rs b/src/test/compile-fail/feature-gate-lang-items.rs
new file mode 100644
index 0000000000000..0435ff4c332d5
--- /dev/null
+++ b/src/test/compile-fail/feature-gate-lang-items.rs
@@ -0,0 +1,15 @@
+// Copyright 2014 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 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#[lang="foo"] //~ ERROR language items are subject to change
+trait Foo {}
+
+fn main() {
+}
diff --git a/src/test/compile-fail/linkage1.rs b/src/test/compile-fail/linkage1.rs
index 35f93c13fb5e2..555cc2b9a7aad 100644
--- a/src/test/compile-fail/linkage1.rs
+++ b/src/test/compile-fail/linkage1.rs
@@ -11,5 +11,4 @@
extern {
#[linkage = "extern_weak"] static foo: isize;
//~^ ERROR: the `linkage` attribute is experimental and not portable
- //~^^ ERROR: the `linkage` attribute is experimental and not portable
}
diff --git a/src/test/compile-fail/malformed-plugin-1.rs b/src/test/compile-fail/malformed-plugin-1.rs
index 254a797ef1cd0..214a5e5e3eb11 100644
--- a/src/test/compile-fail/malformed-plugin-1.rs
+++ b/src/test/compile-fail/malformed-plugin-1.rs
@@ -8,6 +8,7 @@
// option. This file may not be copied, modified, or distributed
// except according to those terms.
+#![feature(plugin)]
#![plugin] //~ ERROR malformed plugin attribute
fn main() {}
diff --git a/src/test/compile-fail/malformed-plugin-2.rs b/src/test/compile-fail/malformed-plugin-2.rs
index 884087b7bc534..1b112608beeb2 100644
--- a/src/test/compile-fail/malformed-plugin-2.rs
+++ b/src/test/compile-fail/malformed-plugin-2.rs
@@ -8,6 +8,7 @@
// option. This file may not be copied, modified, or distributed
// except according to those terms.
+#![feature(plugin)]
#![plugin="bleh"] //~ ERROR malformed plugin attribute
fn main() {}
diff --git a/src/test/compile-fail/malformed-plugin-3.rs b/src/test/compile-fail/malformed-plugin-3.rs
index 4885bb901df68..0c948831de217 100644
--- a/src/test/compile-fail/malformed-plugin-3.rs
+++ b/src/test/compile-fail/malformed-plugin-3.rs
@@ -8,6 +8,7 @@
// option. This file may not be copied, modified, or distributed
// except according to those terms.
+#![feature(plugin)]
#![plugin(foo="bleh")] //~ ERROR malformed plugin attribute
fn main() {}
diff --git a/src/test/compile-fail/plugin-extern-crate-attr-deprecated.rs b/src/test/compile-fail/plugin-extern-crate-attr-deprecated.rs
index ccda5cbdceba6..efa352e386d4d 100644
--- a/src/test/compile-fail/plugin-extern-crate-attr-deprecated.rs
+++ b/src/test/compile-fail/plugin-extern-crate-attr-deprecated.rs
@@ -8,6 +8,8 @@
// option. This file may not be copied, modified, or distributed
// except according to those terms.
+#![feature(plugin)]
+
#[plugin] //~ ERROR #[plugin] on `extern crate` is deprecated
//~^ HELP use a crate attribute instead, i.e. #![plugin(std)]
extern crate std;
diff --git a/src/test/compile-fail/reserved-attr-on-macro.rs b/src/test/compile-fail/reserved-attr-on-macro.rs
new file mode 100644
index 0000000000000..db8f82a70e103
--- /dev/null
+++ b/src/test/compile-fail/reserved-attr-on-macro.rs
@@ -0,0 +1,18 @@
+// 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 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#[rustc_attribute_should_be_reserved] //~ ERROR attributes with the prefix `rustc_` are reserved
+macro_rules! foo {
+ () => (());
+}
+
+fn main() {
+ foo!();
+}
diff --git a/src/test/run-pass-fulldeps/macro-crate.rs b/src/test/run-pass-fulldeps/macro-crate.rs
index 58ccd79b7121d..7a2846c31b663 100644
--- a/src/test/run-pass-fulldeps/macro-crate.rs
+++ b/src/test/run-pass-fulldeps/macro-crate.rs
@@ -11,7 +11,7 @@
// aux-build:macro_crate_test.rs
// ignore-stage1
-#![feature(plugin)]
+#![feature(plugin, custom_attribute)]
#![plugin(macro_crate_test)]
#[macro_use] #[no_link]
From 491054f08e2aaaa8438f1a9943f115dad9da1c6b Mon Sep 17 00:00:00 2001
From: Keegan McAllister <kmcallister@mozilla.com>
Date: Fri, 6 Mar 2015 13:15:54 -0800
Subject: [PATCH 3/3] Make #[derive(Anything)] into sugar for
#[derive_Anything]
This is a hack, but I don't think we can do much better as long as `derive` is
running at the syntax expansion phase.
If the custom_derive feature gate is enabled, this works with user-defined
traits and syntax extensions. Without the gate, you can't use e.g. #[derive_Clone]
directly, so this does not change the stable language.
This commit also cleans up the deriving code somewhat, and forbids some
previously-meaningless attribute syntax. For this reason it's technically a
[breaking-change]
---
src/doc/reference.md | 4 +
src/libsyntax/ext/base.rs | 6 +-
src/libsyntax/ext/deriving/bounds.rs | 45 ++--
src/libsyntax/ext/deriving/mod.rs | 212 ++++++++++--------
src/libsyntax/ext/expand.rs | 1 +
src/libsyntax/feature_gate.rs | 14 ++
src/test/auxiliary/custom_derive_plugin.rs | 74 ++++++
src/test/compile-fail/deriving-bounds.rs | 6 +-
.../deriving-meta-unknown-trait.rs | 3 +-
.../compile-fail/malformed-derive-entry.rs | 25 +++
src/test/compile-fail/single-derive-attr.rs | 15 ++
src/test/run-pass-fulldeps/derive-totalsum.rs | 59 +++++
src/test/run-pass/deprecated-derive.rs | 15 ++
.../run-pass/single-derive-attr-with-gate.rs | 18 ++
14 files changed, 372 insertions(+), 125 deletions(-)
create mode 100644 src/test/auxiliary/custom_derive_plugin.rs
create mode 100644 src/test/compile-fail/malformed-derive-entry.rs
create mode 100644 src/test/compile-fail/single-derive-attr.rs
create mode 100644 src/test/run-pass-fulldeps/derive-totalsum.rs
create mode 100644 src/test/run-pass/deprecated-derive.rs
create mode 100644 src/test/run-pass/single-derive-attr-with-gate.rs
diff --git a/src/doc/reference.md b/src/doc/reference.md
index 95ccc71532a34..a772d98583e49 100644
--- a/src/doc/reference.md
+++ b/src/doc/reference.md
@@ -2429,6 +2429,10 @@ The currently implemented features of the reference compiler are:
so that new attributes can be added in a bacwards compatible
manner (RFC 572).
+* `custom_derive` - Allows the use of `#[derive(Foo,Bar)]` as sugar for
+ `#[derive_Foo] #[derive_Bar]`, which can be user-defined syntax
+ extensions.
+
* `intrinsics` - Allows use of the "rust-intrinsics" ABI. Compiler intrinsics
are inherently unstable and no promise about them is made.
diff --git a/src/libsyntax/ext/base.rs b/src/libsyntax/ext/base.rs
index 5513b44235d2c..8aeafe419daa9 100644
--- a/src/libsyntax/ext/base.rs
+++ b/src/libsyntax/ext/base.rs
@@ -491,10 +491,8 @@ fn initial_syntax_expander_table<'feat>(ecfg: &expand::ExpansionConfig<'feat>)
syntax_expanders.insert(intern("log_syntax"),
builtin_normal_expander(
ext::log_syntax::expand_syntax_ext));
- syntax_expanders.insert(intern("derive"),
- Decorator(Box::new(ext::deriving::expand_meta_derive)));
- syntax_expanders.insert(intern("deriving"),
- Decorator(Box::new(ext::deriving::expand_deprecated_deriving)));
+
+ ext::deriving::register_all(&mut syntax_expanders);
if ecfg.enable_quotes() {
// Quasi-quoting expanders
diff --git a/src/libsyntax/ext/deriving/bounds.rs b/src/libsyntax/ext/deriving/bounds.rs
index 93098484ae013..e408c99935d1c 100644
--- a/src/libsyntax/ext/deriving/bounds.rs
+++ b/src/libsyntax/ext/deriving/bounds.rs
@@ -8,47 +8,34 @@
// option. This file may not be copied, modified, or distributed
// except according to those terms.
-use ast::{MetaItem, MetaWord, Item};
+use ast::{MetaItem, Item};
use codemap::Span;
use ext::base::ExtCtxt;
use ext::deriving::generic::*;
use ext::deriving::generic::ty::*;
use ptr::P;
-pub fn expand_deriving_bound<F>(cx: &mut ExtCtxt,
- span: Span,
- mitem: &MetaItem,
- item: &Item,
- push: F) where
+pub fn expand_deriving_unsafe_bound<F>(cx: &mut ExtCtxt,
+ span: Span,
+ _: &MetaItem,
+ _: &Item,
+ _: F) where
F: FnOnce(P<Item>),
{
- let name = match mitem.node {
- MetaWord(ref tname) => {
- match &tname[..] {
- "Copy" => "Copy",
- "Send" | "Sync" => {
- return cx.span_err(span,
- &format!("{} is an unsafe trait and it \
- should be implemented explicitly",
- *tname))
- }
- ref tname => {
- cx.span_bug(span,
- &format!("expected built-in trait name but \
- found {}", *tname))
- }
- }
- },
- _ => {
- return cx.span_err(span, "unexpected value in deriving, expected \
- a trait")
- }
- };
+ cx.span_err(span, "this unsafe trait should be implemented explicitly");
+}
+pub fn expand_deriving_copy<F>(cx: &mut ExtCtxt,
+ span: Span,
+ mitem: &MetaItem,
+ item: &Item,
+ push: F) where
+ F: FnOnce(P<Item>),
+{
let path = Path::new(vec![
if cx.use_std { "std" } else { "core" },
"marker",
- name
+ "Copy",
]);
let trait_def = TraitDef {
diff --git a/src/libsyntax/ext/deriving/mod.rs b/src/libsyntax/ext/deriving/mod.rs
index 973c8f5fa1e0b..2631c28cf2fe9 100644
--- a/src/libsyntax/ext/deriving/mod.rs
+++ b/src/libsyntax/ext/deriving/mod.rs
@@ -1,4 +1,4 @@
-// Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
+// Copyright 2012-2015 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
@@ -13,9 +13,13 @@
//! FIXME (#2810): hygiene. Search for "__" strings (in other files too). We also assume "extra" is
//! the standard library, and "std" is the core library.
-use ast::{Item, MetaItem, MetaList, MetaNameValue, MetaWord};
-use ext::base::ExtCtxt;
+use ast::{Item, MetaItem, MetaWord};
+use attr::AttrMetaMethods;
+use ext::base::{ExtCtxt, SyntaxEnv, Decorator, ItemDecorator, Modifier};
+use ext::build::AstBuilder;
+use feature_gate;
use codemap::Span;
+use parse::token::{intern, intern_and_get_ident};
use ptr::P;
macro_rules! pathvec {
@@ -74,101 +78,133 @@ pub mod totalord;
pub mod generic;
-pub fn expand_deprecated_deriving(cx: &mut ExtCtxt,
- span: Span,
- _: &MetaItem,
- _: &Item,
- _: &mut FnMut(P<Item>)) {
+fn expand_deprecated_deriving(cx: &mut ExtCtxt,
+ span: Span,
+ _: &MetaItem,
+ _: &Item,
+ _: &mut FnMut(P<Item>)) {
cx.span_err(span, "`deriving` has been renamed to `derive`");
}
-pub fn expand_meta_derive(cx: &mut ExtCtxt,
- _span: Span,
- mitem: &MetaItem,
- item: &Item,
- push: &mut FnMut(P<Item>)) {
- match mitem.node {
- MetaNameValue(_, ref l) => {
- cx.span_err(l.span, "unexpected value in `derive`");
+fn expand_derive(cx: &mut ExtCtxt,
+ _: Span,
+ mitem: &MetaItem,
+ item: P<Item>) -> P<Item> {
+ item.map(|mut item| {
+ if mitem.value_str().is_some() {
+ cx.span_err(mitem.span, "unexpected value in `derive`");
}
- MetaWord(_) => {
+
+ let traits = mitem.meta_item_list().unwrap_or(&[]);
+ if traits.is_empty() {
cx.span_warn(mitem.span, "empty trait list in `derive`");
}
- MetaList(_, ref titems) if titems.len() == 0 => {
- cx.span_warn(mitem.span, "empty trait list in `derive`");
+
+ for titem in traits.iter().rev() {
+ let tname = match titem.node {
+ MetaWord(ref tname) => tname,
+ _ => {
+ cx.span_err(titem.span, "malformed `derive` entry");
+ continue;
+ }
+ };
+
+ if !(is_builtin_trait(tname) || cx.ecfg.enable_custom_derive()) {
+ feature_gate::emit_feature_err(&cx.parse_sess.span_diagnostic,
+ "custom_derive",
+ titem.span,
+ feature_gate::EXPLAIN_CUSTOM_DERIVE);
+ continue;
+ }
+
+ // #[derive(Foo, Bar)] expands to #[derive_Foo] #[derive_Bar]
+ item.attrs.push(cx.attribute(titem.span, cx.meta_word(titem.span,
+ intern_and_get_ident(&format!("derive_{}", tname)))));
}
- MetaList(_, ref titems) => {
- for titem in titems.iter().rev() {
- match titem.node {
- MetaNameValue(ref tname, _) |
- MetaList(ref tname, _) |
- MetaWord(ref tname) => {
- macro_rules! expand {
- ($func:path) => ($func(cx, titem.span, &**titem, item,
- |i| push(i)))
- }
-
- match &tname[..] {
- "Clone" => expand!(clone::expand_deriving_clone),
-
- "Hash" => expand!(hash::expand_deriving_hash),
-
- "RustcEncodable" => {
- expand!(encodable::expand_deriving_rustc_encodable)
- }
- "RustcDecodable" => {
- expand!(decodable::expand_deriving_rustc_decodable)
- }
- "Encodable" => {
- cx.span_warn(titem.span,
- "derive(Encodable) is deprecated \
- in favor of derive(RustcEncodable)");
-
- expand!(encodable::expand_deriving_encodable)
- }
- "Decodable" => {
- cx.span_warn(titem.span,
- "derive(Decodable) is deprecated \
- in favor of derive(RustcDecodable)");
-
- expand!(decodable::expand_deriving_decodable)
- }
-
- "PartialEq" => expand!(eq::expand_deriving_eq),
- "Eq" => expand!(totaleq::expand_deriving_totaleq),
- "PartialOrd" => expand!(ord::expand_deriving_ord),
- "Ord" => expand!(totalord::expand_deriving_totalord),
-
- "Rand" => expand!(rand::expand_deriving_rand),
-
- "Show" => {
- cx.span_warn(titem.span,
- "derive(Show) is deprecated \
- in favor of derive(Debug)");
-
- expand!(show::expand_deriving_show)
- },
-
- "Debug" => expand!(show::expand_deriving_show),
-
- "Default" => expand!(default::expand_deriving_default),
-
- "FromPrimitive" => expand!(primitive::expand_deriving_from_primitive),
-
- "Send" => expand!(bounds::expand_deriving_bound),
- "Sync" => expand!(bounds::expand_deriving_bound),
- "Copy" => expand!(bounds::expand_deriving_bound),
-
- ref tname => {
- cx.span_err(titem.span,
- &format!("unknown `derive` \
- trait: `{}`",
- *tname));
- }
- };
+
+ item
+ })
+}
+
+macro_rules! derive_traits {
+ ($( $name:expr => $func:path, )*) => {
+ pub fn register_all(env: &mut SyntaxEnv) {
+ // Define the #[derive_*] extensions.
+ $({
+ struct DeriveExtension;
+
+ impl ItemDecorator for DeriveExtension {
+ fn expand(&self,
+ ecx: &mut ExtCtxt,
+ sp: Span,
+ mitem: &MetaItem,
+ item: &Item,
+ push: &mut FnMut(P<Item>)) {
+ warn_if_deprecated(ecx, sp, $name);
+ $func(ecx, sp, mitem, item, |i| push(i));
}
}
+
+ env.insert(intern(concat!("derive_", $name)),
+ Decorator(Box::new(DeriveExtension)));
+ })*
+
+ env.insert(intern("derive"),
+ Modifier(Box::new(expand_derive)));
+ env.insert(intern("deriving"),
+ Decorator(Box::new(expand_deprecated_deriving)));
+ }
+
+ fn is_builtin_trait(name: &str) -> bool {
+ match name {
+ $( $name )|* => true,
+ _ => false,
}
}
}
}
+
+derive_traits! {
+ "Clone" => clone::expand_deriving_clone,
+
+ "Hash" => hash::expand_deriving_hash,
+
+ "RustcEncodable" => encodable::expand_deriving_rustc_encodable,
+
+ "RustcDecodable" => decodable::expand_deriving_rustc_decodable,
+
+ "PartialEq" => eq::expand_deriving_eq,
+ "Eq" => totaleq::expand_deriving_totaleq,
+ "PartialOrd" => ord::expand_deriving_ord,
+ "Ord" => totalord::expand_deriving_totalord,
+
+ "Rand" => rand::expand_deriving_rand,
+
+ "Debug" => show::expand_deriving_show,
+
+ "Default" => default::expand_deriving_default,
+
+ "FromPrimitive" => primitive::expand_deriving_from_primitive,
+
+ "Send" => bounds::expand_deriving_unsafe_bound,
+ "Sync" => bounds::expand_deriving_unsafe_bound,
+ "Copy" => bounds::expand_deriving_copy,
+
+ // deprecated
+ "Show" => show::expand_deriving_show,
+ "Encodable" => encodable::expand_deriving_encodable,
+ "Decodable" => decodable::expand_deriving_decodable,
+}
+
+#[inline] // because `name` is a compile-time constant
+fn warn_if_deprecated(ecx: &mut ExtCtxt, sp: Span, name: &str) {
+ if let Some(replacement) = match name {
+ "Show" => Some("Debug"),
+ "Encodable" => Some("RustcEncodable"),
+ "Decodable" => Some("RustcDecodable"),
+ _ => None,
+ } {
+ ecx.span_warn(sp, &format!("derive({}) is deprecated in favor of derive({})",
+ name, replacement));
+ }
+}
diff --git a/src/libsyntax/ext/expand.rs b/src/libsyntax/ext/expand.rs
index 84b0299925211..db8819ef82c2e 100644
--- a/src/libsyntax/ext/expand.rs
+++ b/src/libsyntax/ext/expand.rs
@@ -1476,6 +1476,7 @@ impl<'feat> ExpansionConfig<'feat> {
fn enable_concat_idents = allow_concat_idents,
fn enable_trace_macros = allow_trace_macros,
fn enable_allow_internal_unstable = allow_internal_unstable,
+ fn enable_custom_derive = allow_custom_derive,
}
}
diff --git a/src/libsyntax/feature_gate.rs b/src/libsyntax/feature_gate.rs
index eff86757fd0b2..425c517cb29fd 100644
--- a/src/libsyntax/feature_gate.rs
+++ b/src/libsyntax/feature_gate.rs
@@ -137,6 +137,10 @@ const KNOWN_FEATURES: &'static [(&'static str, &'static str, Status)] = &[
// Allows the use of custom attributes; RFC 572
("custom_attribute", "1.0.0", Active),
+ // Allows the use of #[derive(Anything)] as sugar for
+ // #[derive_Anything].
+ ("custom_derive", "1.0.0", Active),
+
// Allows the use of rustc_* attributes; RFC 572
("rustc_attrs", "1.0.0", Active),
@@ -319,6 +323,7 @@ pub struct Features {
pub allow_concat_idents: bool,
pub allow_trace_macros: bool,
pub allow_internal_unstable: bool,
+ pub allow_custom_derive: bool,
pub old_orphan_check: bool,
pub simd_ffi: bool,
pub unmarked_api: bool,
@@ -340,6 +345,7 @@ impl Features {
allow_concat_idents: false,
allow_trace_macros: false,
allow_internal_unstable: false,
+ allow_custom_derive: false,
old_orphan_check: false,
simd_ffi: false,
unmarked_api: false,
@@ -391,6 +397,10 @@ impl<'a> Context<'a> {
"unless otherwise specified, attributes \
with the prefix `rustc_` \
are reserved for internal compiler diagnostics");
+ } else if name.starts_with("derive_") {
+ self.gate_feature("custom_derive", attr.span,
+ "attributes of the form `#[derive_*]` are reserved
+ for the compiler");
} else {
self.gate_feature("custom_attribute", attr.span,
format!("The attribute `{}` is currently \
@@ -432,6 +442,9 @@ pub const EXPLAIN_TRACE_MACROS: &'static str =
pub const EXPLAIN_ALLOW_INTERNAL_UNSTABLE: &'static str =
"allow_internal_unstable side-steps feature gating and stability checks";
+pub const EXPLAIN_CUSTOM_DERIVE: &'static str =
+ "`#[derive]` for custom traits is not stable enough for use and is subject to change";
+
struct MacroVisitor<'a> {
context: &'a Context<'a>
}
@@ -780,6 +793,7 @@ fn check_crate_inner<F>(cm: &CodeMap, span_handler: &SpanHandler, krate: &ast::C
allow_concat_idents: cx.has_feature("concat_idents"),
allow_trace_macros: cx.has_feature("trace_macros"),
allow_internal_unstable: cx.has_feature("allow_internal_unstable"),
+ allow_custom_derive: cx.has_feature("custom_derive"),
old_orphan_check: cx.has_feature("old_orphan_check"),
simd_ffi: cx.has_feature("simd_ffi"),
unmarked_api: cx.has_feature("unmarked_api"),
diff --git a/src/test/auxiliary/custom_derive_plugin.rs b/src/test/auxiliary/custom_derive_plugin.rs
new file mode 100644
index 0000000000000..e268896480480
--- /dev/null
+++ b/src/test/auxiliary/custom_derive_plugin.rs
@@ -0,0 +1,74 @@
+// 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 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// force-host
+
+#![feature(plugin_registrar)]
+#![feature(box_syntax)]
+#![feature(rustc_private)]
+
+extern crate syntax;
+extern crate rustc;
+
+use syntax::ast;
+use syntax::codemap::Span;
+use syntax::ext::base::{Decorator, ExtCtxt};
+use syntax::ext::build::AstBuilder;
+use syntax::ext::deriving::generic::{cs_fold, TraitDef, MethodDef, combine_substructure};
+use syntax::ext::deriving::generic::ty::{Literal, LifetimeBounds, Path, borrowed_explicit_self};
+use syntax::parse::token;
+use syntax::ptr::P;
+use rustc::plugin::Registry;
+
+#[plugin_registrar]
+pub fn plugin_registrar(reg: &mut Registry) {
+ reg.register_syntax_extension(
+ token::intern("derive_TotalSum"),
+ Decorator(box expand));
+}
+
+fn expand(cx: &mut ExtCtxt,
+ span: Span,
+ mitem: &ast::MetaItem,
+ item: &ast::Item,
+ push: &mut FnMut(P<ast::Item>)) {
+ let trait_def = TraitDef {
+ span: span,
+ attributes: vec![],
+ path: Path::new(vec!["TotalSum"]),
+ additional_bounds: vec![],
+ generics: LifetimeBounds::empty(),
+ associated_types: vec![],
+ methods: vec![
+ MethodDef {
+ name: "total_sum",
+ generics: LifetimeBounds::empty(),
+ explicit_self: borrowed_explicit_self(),
+ args: vec![],
+ ret_ty: Literal(Path::new_local("isize")),
+ attributes: vec![],
+ combine_substructure: combine_substructure(box |cx, span, substr| {
+ let zero = cx.expr_int(span, 0);
+ cs_fold(false,
+ |cx, span, subexpr, field, _| {
+ cx.expr_binary(span, ast::BiAdd, subexpr,
+ cx.expr_method_call(span, field,
+ token::str_to_ident("total_sum"), vec![]))
+ },
+ zero,
+ box |cx, span, _, _| { cx.span_bug(span, "wtf??"); },
+ cx, span, substr)
+ }),
+ },
+ ],
+ };
+
+ trait_def.expand(cx, mitem, item, |i| push(i))
+}
diff --git a/src/test/compile-fail/deriving-bounds.rs b/src/test/compile-fail/deriving-bounds.rs
index c0bcbb284a15e..72d06274de471 100644
--- a/src/test/compile-fail/deriving-bounds.rs
+++ b/src/test/compile-fail/deriving-bounds.rs
@@ -8,12 +8,12 @@
// option. This file may not be copied, modified, or distributed
// except according to those terms.
-#[derive(Copy(Bad))]
-//~^ ERROR unexpected value in deriving, expected a trait
+#[derive(Send)]
+//~^ ERROR this unsafe trait should be implemented explicitly
struct Test;
#[derive(Sync)]
-//~^ ERROR Sync is an unsafe trait and it should be implemented explicitly
+//~^ ERROR this unsafe trait should be implemented explicitly
struct Test1;
pub fn main() {}
diff --git a/src/test/compile-fail/deriving-meta-unknown-trait.rs b/src/test/compile-fail/deriving-meta-unknown-trait.rs
index 6b85656bdd9e6..e223499469355 100644
--- a/src/test/compile-fail/deriving-meta-unknown-trait.rs
+++ b/src/test/compile-fail/deriving-meta-unknown-trait.rs
@@ -8,7 +8,8 @@
// option. This file may not be copied, modified, or distributed
// except according to those terms.
-#[derive(Eqr)] //~ ERROR unknown `derive` trait: `Eqr`
+#[derive(Eqr)]
+//~^ ERROR `#[derive]` for custom traits is not stable enough for use and is subject to change
struct Foo;
pub fn main() {}
diff --git a/src/test/compile-fail/malformed-derive-entry.rs b/src/test/compile-fail/malformed-derive-entry.rs
new file mode 100644
index 0000000000000..62dbc21495a54
--- /dev/null
+++ b/src/test/compile-fail/malformed-derive-entry.rs
@@ -0,0 +1,25 @@
+// 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 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#[derive(Copy(Bad))]
+//~^ ERROR malformed `derive` entry
+struct Test1;
+
+#[derive(Copy="bad")]
+//~^ ERROR malformed `derive` entry
+struct Test2;
+
+#[derive()]
+//~^ WARNING empty trait list
+struct Test3;
+
+#[derive]
+//~^ WARNING empty trait list
+struct Test4;
diff --git a/src/test/compile-fail/single-derive-attr.rs b/src/test/compile-fail/single-derive-attr.rs
new file mode 100644
index 0000000000000..0b1b3141f5bf7
--- /dev/null
+++ b/src/test/compile-fail/single-derive-attr.rs
@@ -0,0 +1,15 @@
+// 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 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#[derive_Clone]
+//~^ ERROR attributes of the form `#[derive_*]` are reserved
+struct Test;
+
+pub fn main() {}
diff --git a/src/test/run-pass-fulldeps/derive-totalsum.rs b/src/test/run-pass-fulldeps/derive-totalsum.rs
new file mode 100644
index 0000000000000..848b2425e4496
--- /dev/null
+++ b/src/test/run-pass-fulldeps/derive-totalsum.rs
@@ -0,0 +1,59 @@
+// 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 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// aux-build:custom_derive_plugin.rs
+// ignore-stage1
+
+#![feature(plugin, custom_derive)]
+#![plugin(custom_derive_plugin)]
+
+trait TotalSum {
+ fn total_sum(&self) -> isize;
+}
+
+impl TotalSum for isize {
+ fn total_sum(&self) -> isize {
+ *self
+ }
+}
+
+struct Seven;
+
+impl TotalSum for Seven {
+ fn total_sum(&self) -> isize {
+ 7
+ }
+}
+
+#[derive(TotalSum)]
+struct Foo {
+ seven: Seven,
+ bar: Bar,
+ baz: isize,
+}
+
+#[derive(TotalSum)]
+struct Bar {
+ quux: isize,
+ bleh: isize,
+}
+
+
+pub fn main() {
+ let v = Foo {
+ seven: Seven,
+ bar: Bar {
+ quux: 9,
+ bleh: 3,
+ },
+ baz: 80,
+ };
+ assert_eq!(v.total_sum(), 99);
+}
diff --git a/src/test/run-pass/deprecated-derive.rs b/src/test/run-pass/deprecated-derive.rs
new file mode 100644
index 0000000000000..494d62c773770
--- /dev/null
+++ b/src/test/run-pass/deprecated-derive.rs
@@ -0,0 +1,15 @@
+// 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 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#[derive(Show)]
+//~^ WARNING derive(Show) is deprecated
+struct Test1;
+
+fn main() { }
diff --git a/src/test/run-pass/single-derive-attr-with-gate.rs b/src/test/run-pass/single-derive-attr-with-gate.rs
new file mode 100644
index 0000000000000..cc5d8fc78911d
--- /dev/null
+++ b/src/test/run-pass/single-derive-attr-with-gate.rs
@@ -0,0 +1,18 @@
+// 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 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![feature(custom_derive)]
+
+#[derive_Clone]
+struct Test;
+
+pub fn main() {
+ Test.clone();
+}