From 33e3da831c8b517c94d85599edf2bcd259128181 Mon Sep 17 00:00:00 2001 From: Jeffrey Seyfried Date: Sat, 15 Oct 2016 20:50:30 +0000 Subject: [PATCH] Use the macro namespace for custom derives. --- src/librustc/middle/cstore.rs | 3 +- src/librustc_metadata/macro_import.rs | 3 +- src/librustc_resolve/build_reduced_graph.rs | 51 +++++++++++---------- src/librustc_resolve/lib.rs | 3 -- src/librustc_resolve/macros.rs | 6 +-- src/libsyntax/ext/base.rs | 4 +- src/libsyntax/ext/expand.rs | 15 +++++- src/libsyntax_ext/deriving/mod.rs | 24 +++++++--- 8 files changed, 62 insertions(+), 47 deletions(-) diff --git a/src/librustc/middle/cstore.rs b/src/librustc/middle/cstore.rs index dfd6256c357..b54862ae0ad 100644 --- a/src/librustc/middle/cstore.rs +++ b/src/librustc/middle/cstore.rs @@ -35,7 +35,6 @@ use session::Session; use session::search_paths::PathKind; use util::nodemap::{NodeSet, DefIdMap}; use std::path::PathBuf; -use std::rc::Rc; use syntax::ast; use syntax::attr; use syntax::ext::base::MultiItemModifier; @@ -425,7 +424,7 @@ pub struct LoadedMacro { pub enum LoadedMacroKind { Def(ast::MacroDef), - CustomDerive(String, Rc), + CustomDerive(String, Box), } pub trait CrateLoader { diff --git a/src/librustc_metadata/macro_import.rs b/src/librustc_metadata/macro_import.rs index 7cd03b2d5b9..3b1b2a4cd27 100644 --- a/src/librustc_metadata/macro_import.rs +++ b/src/librustc_metadata/macro_import.rs @@ -11,7 +11,6 @@ //! Used by `rustc` when loading a crate with exported macros. use std::collections::HashSet; -use std::rc::Rc; use std::env; use std::mem; @@ -212,7 +211,7 @@ impl<'a> CrateLoader<'a> { fn register_custom_derive(&mut self, trait_name: &str, expand: fn(TokenStream) -> TokenStream) { - let derive = Rc::new(CustomDerive::new(expand)); + let derive = Box::new(CustomDerive::new(expand)); self.0.push(LoadedMacro { kind: LoadedMacroKind::CustomDerive(trait_name.to_string(), derive), import_site: self.1, diff --git a/src/librustc_resolve/build_reduced_graph.rs b/src/librustc_resolve/build_reduced_graph.rs index 5600669d45f..dac9e57be32 100644 --- a/src/librustc_resolve/build_reduced_graph.rs +++ b/src/librustc_resolve/build_reduced_graph.rs @@ -36,7 +36,7 @@ use syntax::parse::token; use syntax::ast::{self, Block, ForeignItem, ForeignItemKind, Item, ItemKind}; use syntax::ast::{Mutability, StmtKind, TraitItem, TraitItemKind}; use syntax::ast::{Variant, ViewPathGlob, ViewPathList, ViewPathSimple}; -use syntax::ext::base::{MultiItemModifier, Resolver as SyntaxResolver}; +use syntax::ext::base::{SyntaxExtension, Resolver as SyntaxResolver}; use syntax::ext::hygiene::Mark; use syntax::feature_gate::{self, emit_feature_err}; use syntax::ext::tt::macro_rules; @@ -195,22 +195,25 @@ impl<'b> Resolver<'b> { // We need to error on `#[macro_use] extern crate` when it isn't at the // crate root, because `$crate` won't work properly. let is_crate_root = self.current_module.parent.is_none(); + let import_macro = |this: &mut Self, name, ext, span| { + let shadowing = this.builtin_macros.insert(name, Rc::new(ext)).is_some(); + if shadowing && expansion != Mark::root() { + let msg = format!("`{}` is already in scope", name); + this.session.struct_span_err(span, &msg) + .note("macro-expanded `#[macro_use]`s may not shadow \ + existing macros (see RFC 1560)") + .emit(); + } + }; + + let mut custom_derive_crate = false; for loaded_macro in self.crate_loader.load_macros(item, is_crate_root) { match loaded_macro.kind { LoadedMacroKind::Def(mut def) => { - let name = def.ident.name; if def.use_locally { - let ext = - Rc::new(macro_rules::compile(&self.session.parse_sess, &def)); - if self.builtin_macros.insert(name, ext).is_some() && - expansion != Mark::root() { - let msg = format!("`{}` is already in scope", name); - self.session.struct_span_err(loaded_macro.import_site, &msg) - .note("macro-expanded `#[macro_use]`s may not shadow \ - existing macros (see RFC 1560)") - .emit(); - } - self.macro_names.insert(name); + self.macro_names.insert(def.ident.name); + let ext = macro_rules::compile(&self.session.parse_sess, &def); + import_macro(self, def.ident.name, ext, loaded_macro.import_site); } if def.export { def.id = self.next_node_id(); @@ -218,10 +221,19 @@ impl<'b> Resolver<'b> { } } LoadedMacroKind::CustomDerive(name, ext) => { - self.insert_custom_derive(&name, ext, item.span); + custom_derive_crate = true; + let ext = SyntaxExtension::CustomDerive(ext); + import_macro(self, token::intern(&name), ext, loaded_macro.import_site); } } } + + if custom_derive_crate && !self.session.features.borrow().proc_macro { + let issue = feature_gate::GateIssue::Language; + let msg = "loading custom derive macro crates is experimentally supported"; + emit_feature_err(&self.session.parse_sess, "proc_macro", item.span, issue, msg); + } + self.crate_loader.process_item(item, &self.definitions); // n.b. we don't need to look at the path option here, because cstore already did @@ -504,17 +516,6 @@ impl<'b> Resolver<'b> { false } - - fn insert_custom_derive(&mut self, name: &str, ext: Rc, sp: Span) { - if !self.session.features.borrow().proc_macro { - let sess = &self.session.parse_sess; - let msg = "loading custom derive macro crates is experimentally supported"; - emit_feature_err(sess, "proc_macro", sp, feature_gate::GateIssue::Language, msg); - } - if self.derive_modes.insert(token::intern(name), ext).is_some() { - self.session.span_err(sp, &format!("cannot shadow existing derive mode `{}`", name)); - } - } } pub struct BuildReducedGraphVisitor<'a, 'b: 'a> { diff --git a/src/librustc_resolve/lib.rs b/src/librustc_resolve/lib.rs index 6db844c1d03..21641a17bbf 100644 --- a/src/librustc_resolve/lib.rs +++ b/src/librustc_resolve/lib.rs @@ -53,7 +53,6 @@ use rustc::ty; use rustc::hir::{Freevar, FreevarMap, TraitCandidate, TraitMap, GlobMap}; use rustc::util::nodemap::{NodeMap, NodeSet, FnvHashMap, FnvHashSet}; -use syntax::ext::base::MultiItemModifier; use syntax::ext::hygiene::Mark; use syntax::ast::{self, FloatTy}; use syntax::ast::{CRATE_NODE_ID, Name, NodeId, IntTy, UintTy}; @@ -1080,7 +1079,6 @@ pub struct Resolver<'a> { new_import_semantics: bool, // true if `#![feature(item_like_imports)]` pub exported_macros: Vec, - pub derive_modes: FnvHashMap>, crate_loader: &'a mut CrateLoader, macro_names: FnvHashSet, builtin_macros: FnvHashMap>, @@ -1271,7 +1269,6 @@ impl<'a> Resolver<'a> { new_import_semantics: session.features.borrow().item_like_imports, exported_macros: Vec::new(), - derive_modes: FnvHashMap(), crate_loader: crate_loader, macro_names: FnvHashSet(), builtin_macros: FnvHashMap(), diff --git a/src/librustc_resolve/macros.rs b/src/librustc_resolve/macros.rs index 6741197b79c..cf5ea236b3e 100644 --- a/src/librustc_resolve/macros.rs +++ b/src/librustc_resolve/macros.rs @@ -17,7 +17,7 @@ use std::cell::Cell; use std::rc::Rc; use syntax::ast; use syntax::errors::DiagnosticBuilder; -use syntax::ext::base::{self, Determinacy, MultiModifier, MultiDecorator, MultiItemModifier}; +use syntax::ext::base::{self, Determinacy, MultiModifier, MultiDecorator}; use syntax::ext::base::{NormalTT, SyntaxExtension}; use syntax::ext::expand::Expansion; use syntax::ext::hygiene::Mark; @@ -186,10 +186,6 @@ impl<'a> base::Resolver for Resolver<'a> { } }) } - - fn resolve_derive_mode(&mut self, ident: ast::Ident) -> Option> { - self.derive_modes.get(&ident.name).cloned() - } } impl<'a> Resolver<'a> { diff --git a/src/libsyntax/ext/base.rs b/src/libsyntax/ext/base.rs index 99b883d26d8..11c6f87a655 100644 --- a/src/libsyntax/ext/base.rs +++ b/src/libsyntax/ext/base.rs @@ -508,6 +508,8 @@ pub enum SyntaxExtension { /// the block. /// IdentTT(Box, Option, bool), + + CustomDerive(Box), } pub type NamedSyntaxExtension = (Name, SyntaxExtension); @@ -524,7 +526,6 @@ pub trait Resolver { fn find_attr_invoc(&mut self, attrs: &mut Vec) -> Option; fn resolve_macro(&mut self, scope: Mark, path: &ast::Path, force: bool) -> Result, Determinacy>; - fn resolve_derive_mode(&mut self, ident: ast::Ident) -> Option>; } #[derive(Copy, Clone, Debug)] @@ -545,7 +546,6 @@ impl Resolver for DummyResolver { fn add_expansions_at_stmt(&mut self, _id: ast::NodeId, _macros: Vec) {} fn find_attr_invoc(&mut self, _attrs: &mut Vec) -> Option { None } - fn resolve_derive_mode(&mut self, _ident: ast::Ident) -> Option> { None } fn resolve_macro(&mut self, _scope: Mark, _path: &ast::Path, _force: bool) -> Result, Determinacy> { Err(Determinacy::Determined) diff --git a/src/libsyntax/ext/expand.rs b/src/libsyntax/ext/expand.rs index 3a5b3ab8328..6aeb46fd522 100644 --- a/src/libsyntax/ext/expand.rs +++ b/src/libsyntax/ext/expand.rs @@ -364,7 +364,15 @@ impl<'a, 'b> MacroExpander<'a, 'b> { let tok_result = mac.expand(self.cx, attr.span, attr_toks, item_toks); self.parse_expansion(tok_result, kind, name, attr.span) } - _ => unreachable!(), + SyntaxExtension::CustomDerive(_) => { + self.cx.span_err(attr.span, &format!("`{}` is a derive mode", name)); + kind.dummy(attr.span) + } + _ => { + let msg = &format!("macro `{}` may not be used in attributes", name); + self.cx.span_err(attr.span, &msg); + kind.dummy(attr.span) + } } } @@ -439,6 +447,11 @@ impl<'a, 'b> MacroExpander<'a, 'b> { return kind.dummy(span); } + SyntaxExtension::CustomDerive(..) => { + self.cx.span_err(path.span, &format!("`{}` is a derive mode", extname)); + return kind.dummy(span); + } + SyntaxExtension::ProcMacro(ref expandfun) => { if ident.name != keywords::Invalid.name() { let msg = diff --git a/src/libsyntax_ext/deriving/mod.rs b/src/libsyntax_ext/deriving/mod.rs index 9f99919c895..07401d59a15 100644 --- a/src/libsyntax_ext/deriving/mod.rs +++ b/src/libsyntax_ext/deriving/mod.rs @@ -12,7 +12,7 @@ use syntax::ast::{self, MetaItem}; use syntax::attr::HasAttrs; -use syntax::ext::base::{Annotatable, ExtCtxt}; +use syntax::ext::base::{Annotatable, ExtCtxt, SyntaxExtension}; use syntax::ext::build::AstBuilder; use syntax::feature_gate; use syntax::codemap; @@ -158,10 +158,14 @@ pub fn expand_derive(cx: &mut ExtCtxt, let tword = titem.word().unwrap(); let tname = tword.name(); - let derive_mode = ast::Ident::with_empty_ctxt(intern(&tname)); - let derive_mode = cx.resolver.resolve_derive_mode(derive_mode); - if is_builtin_trait(&tname) || derive_mode.is_some() { - return true + if is_builtin_trait(&tname) || { + let derive_mode = + ast::Path::from_ident(titem.span, ast::Ident::with_empty_ctxt(intern(&tname))); + cx.resolver.resolve_macro(cx.current_expansion.mark, &derive_mode, false).map(|ext| { + if let SyntaxExtension::CustomDerive(_) = *ext { true } else { false } + }).unwrap_or(false) + } { + return true; } if !cx.ecfg.enable_custom_derive() { @@ -216,7 +220,9 @@ pub fn expand_derive(cx: &mut ExtCtxt, .next(); if let Some((i, titem)) = macros_11_derive { let tname = ast::Ident::with_empty_ctxt(intern(&titem.name().unwrap())); - let ext = cx.resolver.resolve_derive_mode(tname).unwrap(); + let path = ast::Path::from_ident(titem.span, tname); + let ext = cx.resolver.resolve_macro(cx.current_expansion.mark, &path, false).unwrap(); + traits.remove(i); if traits.len() > 0 { item = item.map(|mut i| { @@ -232,7 +238,11 @@ pub fn expand_derive(cx: &mut ExtCtxt, intern_and_get_ident("derive"), vec![titem]); let item = Annotatable::Item(item); - return ext.expand(cx, mitem.span, &mitem, item) + if let SyntaxExtension::CustomDerive(ref ext) = *ext { + return ext.expand(cx, mitem.span, &mitem, item); + } else { + unreachable!() + } } // Ok, at this point we know that there are no old-style `#[derive_Foo]` nor