1185 lines
40 KiB
Rust
1185 lines
40 KiB
Rust
use crate::expand::{self, AstFragment, Invocation};
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use syntax::ast::{self, NodeId, Attribute, Name, PatKind};
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use syntax::attr::{self, HasAttrs, Stability, Deprecation};
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use syntax::source_map::SourceMap;
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use syntax::edition::Edition;
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use syntax::mut_visit::{self, MutVisitor};
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use syntax::parse::{self, parser, DirectoryOwnership};
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use syntax::parse::token;
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use syntax::ptr::P;
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use syntax::sess::ParseSess;
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use syntax::symbol::{kw, sym, Ident, Symbol};
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use syntax::{ThinVec, MACRO_ARGUMENTS};
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use syntax::tokenstream::{self, TokenStream};
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use syntax::visit::Visitor;
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crate use syntax::expand::SpecialDerives;
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use errors::{DiagnosticBuilder, DiagnosticId};
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use smallvec::{smallvec, SmallVec};
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use syntax_pos::{FileName, Span, MultiSpan, DUMMY_SP};
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use syntax_pos::hygiene::{AstPass, ExpnId, ExpnData, ExpnKind};
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use rustc_data_structures::fx::FxHashMap;
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use rustc_data_structures::sync::{self, Lrc};
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use std::iter;
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use std::path::PathBuf;
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use std::rc::Rc;
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use std::default::Default;
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crate use syntax_pos::hygiene::MacroKind;
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#[derive(Debug,Clone)]
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pub enum Annotatable {
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Item(P<ast::Item>),
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TraitItem(P<ast::TraitItem>),
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ImplItem(P<ast::ImplItem>),
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ForeignItem(P<ast::ForeignItem>),
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Stmt(P<ast::Stmt>),
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Expr(P<ast::Expr>),
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Arm(ast::Arm),
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Field(ast::Field),
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FieldPat(ast::FieldPat),
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GenericParam(ast::GenericParam),
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Param(ast::Param),
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StructField(ast::StructField),
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Variant(ast::Variant),
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}
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impl HasAttrs for Annotatable {
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fn attrs(&self) -> &[Attribute] {
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match *self {
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Annotatable::Item(ref item) => &item.attrs,
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Annotatable::TraitItem(ref trait_item) => &trait_item.attrs,
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Annotatable::ImplItem(ref impl_item) => &impl_item.attrs,
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Annotatable::ForeignItem(ref foreign_item) => &foreign_item.attrs,
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Annotatable::Stmt(ref stmt) => stmt.attrs(),
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Annotatable::Expr(ref expr) => &expr.attrs,
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Annotatable::Arm(ref arm) => &arm.attrs,
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Annotatable::Field(ref field) => &field.attrs,
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Annotatable::FieldPat(ref fp) => &fp.attrs,
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Annotatable::GenericParam(ref gp) => &gp.attrs,
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Annotatable::Param(ref p) => &p.attrs,
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Annotatable::StructField(ref sf) => &sf.attrs,
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Annotatable::Variant(ref v) => &v.attrs(),
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}
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}
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fn visit_attrs<F: FnOnce(&mut Vec<Attribute>)>(&mut self, f: F) {
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match self {
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Annotatable::Item(item) => item.visit_attrs(f),
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Annotatable::TraitItem(trait_item) => trait_item.visit_attrs(f),
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Annotatable::ImplItem(impl_item) => impl_item.visit_attrs(f),
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Annotatable::ForeignItem(foreign_item) => foreign_item.visit_attrs(f),
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Annotatable::Stmt(stmt) => stmt.visit_attrs(f),
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Annotatable::Expr(expr) => expr.visit_attrs(f),
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Annotatable::Arm(arm) => arm.visit_attrs(f),
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Annotatable::Field(field) => field.visit_attrs(f),
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Annotatable::FieldPat(fp) => fp.visit_attrs(f),
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Annotatable::GenericParam(gp) => gp.visit_attrs(f),
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Annotatable::Param(p) => p.visit_attrs(f),
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Annotatable::StructField(sf) => sf.visit_attrs(f),
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Annotatable::Variant(v) => v.visit_attrs(f),
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}
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}
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}
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impl Annotatable {
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pub fn span(&self) -> Span {
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match *self {
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Annotatable::Item(ref item) => item.span,
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Annotatable::TraitItem(ref trait_item) => trait_item.span,
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Annotatable::ImplItem(ref impl_item) => impl_item.span,
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Annotatable::ForeignItem(ref foreign_item) => foreign_item.span,
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Annotatable::Stmt(ref stmt) => stmt.span,
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Annotatable::Expr(ref expr) => expr.span,
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Annotatable::Arm(ref arm) => arm.span,
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Annotatable::Field(ref field) => field.span,
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Annotatable::FieldPat(ref fp) => fp.pat.span,
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Annotatable::GenericParam(ref gp) => gp.ident.span,
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Annotatable::Param(ref p) => p.span,
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Annotatable::StructField(ref sf) => sf.span,
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Annotatable::Variant(ref v) => v.span,
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}
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}
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pub fn visit_with<'a, V: Visitor<'a>>(&'a self, visitor: &mut V) {
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match self {
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Annotatable::Item(item) => visitor.visit_item(item),
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Annotatable::TraitItem(trait_item) => visitor.visit_trait_item(trait_item),
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Annotatable::ImplItem(impl_item) => visitor.visit_impl_item(impl_item),
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Annotatable::ForeignItem(foreign_item) => visitor.visit_foreign_item(foreign_item),
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Annotatable::Stmt(stmt) => visitor.visit_stmt(stmt),
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Annotatable::Expr(expr) => visitor.visit_expr(expr),
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Annotatable::Arm(arm) => visitor.visit_arm(arm),
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Annotatable::Field(field) => visitor.visit_field(field),
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Annotatable::FieldPat(fp) => visitor.visit_field_pattern(fp),
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Annotatable::GenericParam(gp) => visitor.visit_generic_param(gp),
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Annotatable::Param(p) => visitor.visit_param(p),
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Annotatable::StructField(sf) =>visitor.visit_struct_field(sf),
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Annotatable::Variant(v) => visitor.visit_variant(v),
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}
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}
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pub fn expect_item(self) -> P<ast::Item> {
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match self {
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Annotatable::Item(i) => i,
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_ => panic!("expected Item")
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}
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}
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pub fn map_item_or<F, G>(self, mut f: F, mut or: G) -> Annotatable
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where F: FnMut(P<ast::Item>) -> P<ast::Item>,
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G: FnMut(Annotatable) -> Annotatable
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{
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match self {
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Annotatable::Item(i) => Annotatable::Item(f(i)),
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_ => or(self)
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}
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}
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pub fn expect_trait_item(self) -> ast::TraitItem {
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match self {
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Annotatable::TraitItem(i) => i.into_inner(),
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_ => panic!("expected Item")
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}
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}
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pub fn expect_impl_item(self) -> ast::ImplItem {
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match self {
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Annotatable::ImplItem(i) => i.into_inner(),
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_ => panic!("expected Item")
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}
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}
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pub fn expect_foreign_item(self) -> ast::ForeignItem {
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match self {
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Annotatable::ForeignItem(i) => i.into_inner(),
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_ => panic!("expected foreign item")
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}
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}
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pub fn expect_stmt(self) -> ast::Stmt {
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match self {
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Annotatable::Stmt(stmt) => stmt.into_inner(),
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_ => panic!("expected statement"),
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}
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}
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pub fn expect_expr(self) -> P<ast::Expr> {
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match self {
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Annotatable::Expr(expr) => expr,
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_ => panic!("expected expression"),
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}
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}
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pub fn expect_arm(self) -> ast::Arm {
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match self {
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Annotatable::Arm(arm) => arm,
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_ => panic!("expected match arm")
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}
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}
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pub fn expect_field(self) -> ast::Field {
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match self {
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Annotatable::Field(field) => field,
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_ => panic!("expected field")
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}
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}
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pub fn expect_field_pattern(self) -> ast::FieldPat {
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match self {
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Annotatable::FieldPat(fp) => fp,
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_ => panic!("expected field pattern")
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}
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}
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pub fn expect_generic_param(self) -> ast::GenericParam {
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match self {
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Annotatable::GenericParam(gp) => gp,
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_ => panic!("expected generic parameter")
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}
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}
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pub fn expect_param(self) -> ast::Param {
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match self {
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Annotatable::Param(param) => param,
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_ => panic!("expected parameter")
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}
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}
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pub fn expect_struct_field(self) -> ast::StructField {
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match self {
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Annotatable::StructField(sf) => sf,
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_ => panic!("expected struct field")
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}
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}
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pub fn expect_variant(self) -> ast::Variant {
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match self {
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Annotatable::Variant(v) => v,
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_ => panic!("expected variant")
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}
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}
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pub fn derive_allowed(&self) -> bool {
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match *self {
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Annotatable::Item(ref item) => match item.kind {
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ast::ItemKind::Struct(..) |
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ast::ItemKind::Enum(..) |
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ast::ItemKind::Union(..) => true,
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_ => false,
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},
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_ => false,
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}
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}
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}
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// `meta_item` is the annotation, and `item` is the item being modified.
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// FIXME Decorators should follow the same pattern too.
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pub trait MultiItemModifier {
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fn expand(&self,
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ecx: &mut ExtCtxt<'_>,
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span: Span,
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meta_item: &ast::MetaItem,
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item: Annotatable)
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-> Vec<Annotatable>;
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}
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impl<F, T> MultiItemModifier for F
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where F: Fn(&mut ExtCtxt<'_>, Span, &ast::MetaItem, Annotatable) -> T,
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T: Into<Vec<Annotatable>>,
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{
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fn expand(&self,
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ecx: &mut ExtCtxt<'_>,
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span: Span,
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meta_item: &ast::MetaItem,
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item: Annotatable)
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-> Vec<Annotatable> {
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(*self)(ecx, span, meta_item, item).into()
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}
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}
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impl Into<Vec<Annotatable>> for Annotatable {
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fn into(self) -> Vec<Annotatable> {
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vec![self]
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}
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}
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pub trait ProcMacro {
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fn expand<'cx>(&self,
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ecx: &'cx mut ExtCtxt<'_>,
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span: Span,
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ts: TokenStream)
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-> TokenStream;
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}
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impl<F> ProcMacro for F
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where F: Fn(TokenStream) -> TokenStream
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{
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fn expand<'cx>(&self,
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_ecx: &'cx mut ExtCtxt<'_>,
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_span: Span,
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ts: TokenStream)
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-> TokenStream {
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// FIXME setup implicit context in TLS before calling self.
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(*self)(ts)
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}
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}
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pub trait AttrProcMacro {
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fn expand<'cx>(&self,
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ecx: &'cx mut ExtCtxt<'_>,
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span: Span,
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annotation: TokenStream,
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annotated: TokenStream)
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-> TokenStream;
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}
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impl<F> AttrProcMacro for F
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where F: Fn(TokenStream, TokenStream) -> TokenStream
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{
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fn expand<'cx>(&self,
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_ecx: &'cx mut ExtCtxt<'_>,
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_span: Span,
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annotation: TokenStream,
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annotated: TokenStream)
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-> TokenStream {
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// FIXME setup implicit context in TLS before calling self.
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(*self)(annotation, annotated)
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}
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}
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/// Represents a thing that maps token trees to Macro Results
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pub trait TTMacroExpander {
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fn expand<'cx>(
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&self,
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ecx: &'cx mut ExtCtxt<'_>,
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span: Span,
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input: TokenStream,
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) -> Box<dyn MacResult+'cx>;
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}
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pub type MacroExpanderFn =
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for<'cx> fn(&'cx mut ExtCtxt<'_>, Span, TokenStream)
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-> Box<dyn MacResult+'cx>;
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impl<F> TTMacroExpander for F
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where F: for<'cx> Fn(&'cx mut ExtCtxt<'_>, Span, TokenStream)
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-> Box<dyn MacResult+'cx>
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{
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fn expand<'cx>(
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&self,
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ecx: &'cx mut ExtCtxt<'_>,
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span: Span,
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mut input: TokenStream,
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) -> Box<dyn MacResult+'cx> {
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struct AvoidInterpolatedIdents;
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impl MutVisitor for AvoidInterpolatedIdents {
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fn visit_tt(&mut self, tt: &mut tokenstream::TokenTree) {
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if let tokenstream::TokenTree::Token(token) = tt {
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if let token::Interpolated(nt) = &token.kind {
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if let token::NtIdent(ident, is_raw) = **nt {
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*tt = tokenstream::TokenTree::token(
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token::Ident(ident.name, is_raw), ident.span
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);
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}
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}
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}
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mut_visit::noop_visit_tt(tt, self)
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}
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fn visit_mac(&mut self, mac: &mut ast::Mac) {
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mut_visit::noop_visit_mac(mac, self)
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}
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}
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AvoidInterpolatedIdents.visit_tts(&mut input);
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(*self)(ecx, span, input)
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}
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}
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// Use a macro because forwarding to a simple function has type system issues
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macro_rules! make_stmts_default {
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($me:expr) => {
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$me.make_expr().map(|e| smallvec![ast::Stmt {
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id: ast::DUMMY_NODE_ID,
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span: e.span,
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kind: ast::StmtKind::Expr(e),
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}])
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}
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}
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/// The result of a macro expansion. The return values of the various
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/// methods are spliced into the AST at the callsite of the macro.
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pub trait MacResult {
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/// Creates an expression.
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fn make_expr(self: Box<Self>) -> Option<P<ast::Expr>> {
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None
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}
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/// Creates zero or more items.
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fn make_items(self: Box<Self>) -> Option<SmallVec<[P<ast::Item>; 1]>> {
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None
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}
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/// Creates zero or more impl items.
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fn make_impl_items(self: Box<Self>) -> Option<SmallVec<[ast::ImplItem; 1]>> {
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None
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}
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/// Creates zero or more trait items.
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fn make_trait_items(self: Box<Self>) -> Option<SmallVec<[ast::TraitItem; 1]>> {
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None
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}
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/// Creates zero or more items in an `extern {}` block
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fn make_foreign_items(self: Box<Self>) -> Option<SmallVec<[ast::ForeignItem; 1]>> { None }
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/// Creates a pattern.
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fn make_pat(self: Box<Self>) -> Option<P<ast::Pat>> {
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None
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}
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/// Creates zero or more statements.
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///
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/// By default this attempts to create an expression statement,
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/// returning None if that fails.
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fn make_stmts(self: Box<Self>) -> Option<SmallVec<[ast::Stmt; 1]>> {
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make_stmts_default!(self)
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}
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fn make_ty(self: Box<Self>) -> Option<P<ast::Ty>> {
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None
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}
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fn make_arms(self: Box<Self>) -> Option<SmallVec<[ast::Arm; 1]>> {
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None
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}
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fn make_fields(self: Box<Self>) -> Option<SmallVec<[ast::Field; 1]>> {
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None
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}
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fn make_field_patterns(self: Box<Self>) -> Option<SmallVec<[ast::FieldPat; 1]>> {
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None
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}
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fn make_generic_params(self: Box<Self>) -> Option<SmallVec<[ast::GenericParam; 1]>> {
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None
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}
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fn make_params(self: Box<Self>) -> Option<SmallVec<[ast::Param; 1]>> {
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None
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}
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fn make_struct_fields(self: Box<Self>) -> Option<SmallVec<[ast::StructField; 1]>> {
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None
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}
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fn make_variants(self: Box<Self>) -> Option<SmallVec<[ast::Variant; 1]>> {
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None
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}
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}
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macro_rules! make_MacEager {
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( $( $fld:ident: $t:ty, )* ) => {
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/// `MacResult` implementation for the common case where you've already
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/// built each form of AST that you might return.
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#[derive(Default)]
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pub struct MacEager {
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$(
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pub $fld: Option<$t>,
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)*
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}
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impl MacEager {
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$(
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pub fn $fld(v: $t) -> Box<dyn MacResult> {
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Box::new(MacEager {
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$fld: Some(v),
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..Default::default()
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})
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}
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)*
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}
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}
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}
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make_MacEager! {
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expr: P<ast::Expr>,
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pat: P<ast::Pat>,
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items: SmallVec<[P<ast::Item>; 1]>,
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impl_items: SmallVec<[ast::ImplItem; 1]>,
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trait_items: SmallVec<[ast::TraitItem; 1]>,
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foreign_items: SmallVec<[ast::ForeignItem; 1]>,
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stmts: SmallVec<[ast::Stmt; 1]>,
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ty: P<ast::Ty>,
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}
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impl MacResult for MacEager {
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fn make_expr(self: Box<Self>) -> Option<P<ast::Expr>> {
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self.expr
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}
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fn make_items(self: Box<Self>) -> Option<SmallVec<[P<ast::Item>; 1]>> {
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self.items
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}
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fn make_impl_items(self: Box<Self>) -> Option<SmallVec<[ast::ImplItem; 1]>> {
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self.impl_items
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}
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fn make_trait_items(self: Box<Self>) -> Option<SmallVec<[ast::TraitItem; 1]>> {
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self.trait_items
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}
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fn make_foreign_items(self: Box<Self>) -> Option<SmallVec<[ast::ForeignItem; 1]>> {
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self.foreign_items
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}
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fn make_stmts(self: Box<Self>) -> Option<SmallVec<[ast::Stmt; 1]>> {
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match self.stmts.as_ref().map_or(0, |s| s.len()) {
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0 => make_stmts_default!(self),
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_ => self.stmts,
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}
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|
}
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|
|
fn make_pat(self: Box<Self>) -> Option<P<ast::Pat>> {
|
|
if let Some(p) = self.pat {
|
|
return Some(p);
|
|
}
|
|
if let Some(e) = self.expr {
|
|
if let ast::ExprKind::Lit(_) = e.kind {
|
|
return Some(P(ast::Pat {
|
|
id: ast::DUMMY_NODE_ID,
|
|
span: e.span,
|
|
kind: PatKind::Lit(e),
|
|
}));
|
|
}
|
|
}
|
|
None
|
|
}
|
|
|
|
fn make_ty(self: Box<Self>) -> Option<P<ast::Ty>> {
|
|
self.ty
|
|
}
|
|
}
|
|
|
|
/// Fill-in macro expansion result, to allow compilation to continue
|
|
/// after hitting errors.
|
|
#[derive(Copy, Clone)]
|
|
pub struct DummyResult {
|
|
is_error: bool,
|
|
span: Span,
|
|
}
|
|
|
|
impl DummyResult {
|
|
/// Creates a default MacResult that can be anything.
|
|
///
|
|
/// Use this as a return value after hitting any errors and
|
|
/// calling `span_err`.
|
|
pub fn any(span: Span) -> Box<dyn MacResult+'static> {
|
|
Box::new(DummyResult { is_error: true, span })
|
|
}
|
|
|
|
/// Same as `any`, but must be a valid fragment, not error.
|
|
pub fn any_valid(span: Span) -> Box<dyn MacResult+'static> {
|
|
Box::new(DummyResult { is_error: false, span })
|
|
}
|
|
|
|
/// A plain dummy expression.
|
|
pub fn raw_expr(sp: Span, is_error: bool) -> P<ast::Expr> {
|
|
P(ast::Expr {
|
|
id: ast::DUMMY_NODE_ID,
|
|
kind: if is_error { ast::ExprKind::Err } else { ast::ExprKind::Tup(Vec::new()) },
|
|
span: sp,
|
|
attrs: ThinVec::new(),
|
|
})
|
|
}
|
|
|
|
/// A plain dummy pattern.
|
|
pub fn raw_pat(sp: Span) -> ast::Pat {
|
|
ast::Pat {
|
|
id: ast::DUMMY_NODE_ID,
|
|
kind: PatKind::Wild,
|
|
span: sp,
|
|
}
|
|
}
|
|
|
|
/// A plain dummy type.
|
|
pub fn raw_ty(sp: Span, is_error: bool) -> P<ast::Ty> {
|
|
P(ast::Ty {
|
|
id: ast::DUMMY_NODE_ID,
|
|
kind: if is_error { ast::TyKind::Err } else { ast::TyKind::Tup(Vec::new()) },
|
|
span: sp
|
|
})
|
|
}
|
|
}
|
|
|
|
impl MacResult for DummyResult {
|
|
fn make_expr(self: Box<DummyResult>) -> Option<P<ast::Expr>> {
|
|
Some(DummyResult::raw_expr(self.span, self.is_error))
|
|
}
|
|
|
|
fn make_pat(self: Box<DummyResult>) -> Option<P<ast::Pat>> {
|
|
Some(P(DummyResult::raw_pat(self.span)))
|
|
}
|
|
|
|
fn make_items(self: Box<DummyResult>) -> Option<SmallVec<[P<ast::Item>; 1]>> {
|
|
Some(SmallVec::new())
|
|
}
|
|
|
|
fn make_impl_items(self: Box<DummyResult>) -> Option<SmallVec<[ast::ImplItem; 1]>> {
|
|
Some(SmallVec::new())
|
|
}
|
|
|
|
fn make_trait_items(self: Box<DummyResult>) -> Option<SmallVec<[ast::TraitItem; 1]>> {
|
|
Some(SmallVec::new())
|
|
}
|
|
|
|
fn make_foreign_items(self: Box<Self>) -> Option<SmallVec<[ast::ForeignItem; 1]>> {
|
|
Some(SmallVec::new())
|
|
}
|
|
|
|
fn make_stmts(self: Box<DummyResult>) -> Option<SmallVec<[ast::Stmt; 1]>> {
|
|
Some(smallvec![ast::Stmt {
|
|
id: ast::DUMMY_NODE_ID,
|
|
kind: ast::StmtKind::Expr(DummyResult::raw_expr(self.span, self.is_error)),
|
|
span: self.span,
|
|
}])
|
|
}
|
|
|
|
fn make_ty(self: Box<DummyResult>) -> Option<P<ast::Ty>> {
|
|
Some(DummyResult::raw_ty(self.span, self.is_error))
|
|
}
|
|
|
|
fn make_arms(self: Box<DummyResult>) -> Option<SmallVec<[ast::Arm; 1]>> {
|
|
Some(SmallVec::new())
|
|
}
|
|
|
|
fn make_fields(self: Box<DummyResult>) -> Option<SmallVec<[ast::Field; 1]>> {
|
|
Some(SmallVec::new())
|
|
}
|
|
|
|
fn make_field_patterns(self: Box<DummyResult>) -> Option<SmallVec<[ast::FieldPat; 1]>> {
|
|
Some(SmallVec::new())
|
|
}
|
|
|
|
fn make_generic_params(self: Box<DummyResult>) -> Option<SmallVec<[ast::GenericParam; 1]>> {
|
|
Some(SmallVec::new())
|
|
}
|
|
|
|
fn make_params(self: Box<DummyResult>) -> Option<SmallVec<[ast::Param; 1]>> {
|
|
Some(SmallVec::new())
|
|
}
|
|
|
|
fn make_struct_fields(self: Box<DummyResult>) -> Option<SmallVec<[ast::StructField; 1]>> {
|
|
Some(SmallVec::new())
|
|
}
|
|
|
|
fn make_variants(self: Box<DummyResult>) -> Option<SmallVec<[ast::Variant; 1]>> {
|
|
Some(SmallVec::new())
|
|
}
|
|
}
|
|
|
|
/// A syntax extension kind.
|
|
pub enum SyntaxExtensionKind {
|
|
/// A token-based function-like macro.
|
|
Bang(
|
|
/// An expander with signature TokenStream -> TokenStream.
|
|
Box<dyn ProcMacro + sync::Sync + sync::Send>,
|
|
),
|
|
|
|
/// An AST-based function-like macro.
|
|
LegacyBang(
|
|
/// An expander with signature TokenStream -> AST.
|
|
Box<dyn TTMacroExpander + sync::Sync + sync::Send>,
|
|
),
|
|
|
|
/// A token-based attribute macro.
|
|
Attr(
|
|
/// An expander with signature (TokenStream, TokenStream) -> TokenStream.
|
|
/// The first TokenSteam is the attribute itself, the second is the annotated item.
|
|
/// The produced TokenSteam replaces the input TokenSteam.
|
|
Box<dyn AttrProcMacro + sync::Sync + sync::Send>,
|
|
),
|
|
|
|
/// An AST-based attribute macro.
|
|
LegacyAttr(
|
|
/// An expander with signature (AST, AST) -> AST.
|
|
/// The first AST fragment is the attribute itself, the second is the annotated item.
|
|
/// The produced AST fragment replaces the input AST fragment.
|
|
Box<dyn MultiItemModifier + sync::Sync + sync::Send>,
|
|
),
|
|
|
|
/// A trivial attribute "macro" that does nothing,
|
|
/// only keeps the attribute and marks it as inert,
|
|
/// thus making it ineligible for further expansion.
|
|
NonMacroAttr {
|
|
/// Suppresses the `unused_attributes` lint for this attribute.
|
|
mark_used: bool,
|
|
},
|
|
|
|
/// A token-based derive macro.
|
|
Derive(
|
|
/// An expander with signature TokenStream -> TokenStream (not yet).
|
|
/// The produced TokenSteam is appended to the input TokenSteam.
|
|
Box<dyn MultiItemModifier + sync::Sync + sync::Send>,
|
|
),
|
|
|
|
/// An AST-based derive macro.
|
|
LegacyDerive(
|
|
/// An expander with signature AST -> AST.
|
|
/// The produced AST fragment is appended to the input AST fragment.
|
|
Box<dyn MultiItemModifier + sync::Sync + sync::Send>,
|
|
),
|
|
}
|
|
|
|
/// A struct representing a macro definition in "lowered" form ready for expansion.
|
|
pub struct SyntaxExtension {
|
|
/// A syntax extension kind.
|
|
pub kind: SyntaxExtensionKind,
|
|
/// Span of the macro definition.
|
|
pub span: Span,
|
|
/// Whitelist of unstable features that are treated as stable inside this macro.
|
|
pub allow_internal_unstable: Option<Lrc<[Symbol]>>,
|
|
/// Suppresses the `unsafe_code` lint for code produced by this macro.
|
|
pub allow_internal_unsafe: bool,
|
|
/// Enables the macro helper hack (`ident!(...)` -> `$crate::ident!(...)`) for this macro.
|
|
pub local_inner_macros: bool,
|
|
/// The macro's stability info.
|
|
pub stability: Option<Stability>,
|
|
/// The macro's deprecation info.
|
|
pub deprecation: Option<Deprecation>,
|
|
/// Names of helper attributes registered by this macro.
|
|
pub helper_attrs: Vec<Symbol>,
|
|
/// Edition of the crate in which this macro is defined.
|
|
pub edition: Edition,
|
|
/// Built-in macros have a couple of special properties like availability
|
|
/// in `#[no_implicit_prelude]` modules, so we have to keep this flag.
|
|
pub is_builtin: bool,
|
|
/// We have to identify macros providing a `Copy` impl early for compatibility reasons.
|
|
pub is_derive_copy: bool,
|
|
}
|
|
|
|
impl SyntaxExtension {
|
|
/// Returns which kind of macro calls this syntax extension.
|
|
pub fn macro_kind(&self) -> MacroKind {
|
|
match self.kind {
|
|
SyntaxExtensionKind::Bang(..) |
|
|
SyntaxExtensionKind::LegacyBang(..) => MacroKind::Bang,
|
|
SyntaxExtensionKind::Attr(..) |
|
|
SyntaxExtensionKind::LegacyAttr(..) |
|
|
SyntaxExtensionKind::NonMacroAttr { .. } => MacroKind::Attr,
|
|
SyntaxExtensionKind::Derive(..) |
|
|
SyntaxExtensionKind::LegacyDerive(..) => MacroKind::Derive,
|
|
}
|
|
}
|
|
|
|
/// Constructs a syntax extension with default properties.
|
|
pub fn default(kind: SyntaxExtensionKind, edition: Edition) -> SyntaxExtension {
|
|
SyntaxExtension {
|
|
span: DUMMY_SP,
|
|
allow_internal_unstable: None,
|
|
allow_internal_unsafe: false,
|
|
local_inner_macros: false,
|
|
stability: None,
|
|
deprecation: None,
|
|
helper_attrs: Vec::new(),
|
|
edition,
|
|
is_builtin: false,
|
|
is_derive_copy: false,
|
|
kind,
|
|
}
|
|
}
|
|
|
|
/// Constructs a syntax extension with the given properties
|
|
/// and other properties converted from attributes.
|
|
pub fn new(
|
|
sess: &ParseSess,
|
|
kind: SyntaxExtensionKind,
|
|
span: Span,
|
|
helper_attrs: Vec<Symbol>,
|
|
edition: Edition,
|
|
name: Name,
|
|
attrs: &[ast::Attribute],
|
|
) -> SyntaxExtension {
|
|
let allow_internal_unstable = attr::allow_internal_unstable(
|
|
&attrs, &sess.span_diagnostic,
|
|
).map(|features| features.collect::<Vec<Symbol>>().into());
|
|
|
|
let mut local_inner_macros = false;
|
|
if let Some(macro_export) = attr::find_by_name(attrs, sym::macro_export) {
|
|
if let Some(l) = macro_export.meta_item_list() {
|
|
local_inner_macros = attr::list_contains_name(&l, sym::local_inner_macros);
|
|
}
|
|
}
|
|
|
|
let is_builtin = attr::contains_name(attrs, sym::rustc_builtin_macro);
|
|
|
|
SyntaxExtension {
|
|
kind,
|
|
span,
|
|
allow_internal_unstable,
|
|
allow_internal_unsafe: attr::contains_name(attrs, sym::allow_internal_unsafe),
|
|
local_inner_macros,
|
|
stability: attr::find_stability(&sess, attrs, span),
|
|
deprecation: attr::find_deprecation(&sess, attrs, span),
|
|
helper_attrs,
|
|
edition,
|
|
is_builtin,
|
|
is_derive_copy: is_builtin && name == sym::Copy,
|
|
}
|
|
}
|
|
|
|
pub fn dummy_bang(edition: Edition) -> SyntaxExtension {
|
|
fn expander<'cx>(_: &'cx mut ExtCtxt<'_>, span: Span, _: TokenStream)
|
|
-> Box<dyn MacResult + 'cx> {
|
|
DummyResult::any(span)
|
|
}
|
|
SyntaxExtension::default(SyntaxExtensionKind::LegacyBang(Box::new(expander)), edition)
|
|
}
|
|
|
|
pub fn dummy_derive(edition: Edition) -> SyntaxExtension {
|
|
fn expander(_: &mut ExtCtxt<'_>, _: Span, _: &ast::MetaItem, _: Annotatable)
|
|
-> Vec<Annotatable> {
|
|
Vec::new()
|
|
}
|
|
SyntaxExtension::default(SyntaxExtensionKind::Derive(Box::new(expander)), edition)
|
|
}
|
|
|
|
pub fn non_macro_attr(mark_used: bool, edition: Edition) -> SyntaxExtension {
|
|
SyntaxExtension::default(SyntaxExtensionKind::NonMacroAttr { mark_used }, edition)
|
|
}
|
|
|
|
pub fn expn_data(&self, parent: ExpnId, call_site: Span, descr: Symbol) -> ExpnData {
|
|
ExpnData {
|
|
kind: ExpnKind::Macro(self.macro_kind(), descr),
|
|
parent,
|
|
call_site,
|
|
def_site: self.span,
|
|
allow_internal_unstable: self.allow_internal_unstable.clone(),
|
|
allow_internal_unsafe: self.allow_internal_unsafe,
|
|
local_inner_macros: self.local_inner_macros,
|
|
edition: self.edition,
|
|
}
|
|
}
|
|
}
|
|
|
|
pub type NamedSyntaxExtension = (Name, SyntaxExtension);
|
|
|
|
/// Result of resolving a macro invocation.
|
|
pub enum InvocationRes {
|
|
Single(Lrc<SyntaxExtension>),
|
|
DeriveContainer(Vec<Lrc<SyntaxExtension>>),
|
|
}
|
|
|
|
/// Error type that denotes indeterminacy.
|
|
pub struct Indeterminate;
|
|
|
|
pub trait Resolver {
|
|
fn next_node_id(&mut self) -> NodeId;
|
|
|
|
fn resolve_dollar_crates(&mut self);
|
|
fn visit_ast_fragment_with_placeholders(&mut self, expn_id: ExpnId, fragment: &AstFragment);
|
|
fn register_builtin_macro(&mut self, ident: ast::Ident, ext: SyntaxExtension);
|
|
|
|
fn expansion_for_ast_pass(
|
|
&mut self,
|
|
call_site: Span,
|
|
pass: AstPass,
|
|
features: &[Symbol],
|
|
parent_module_id: Option<NodeId>,
|
|
) -> ExpnId;
|
|
|
|
fn resolve_imports(&mut self);
|
|
|
|
fn resolve_macro_invocation(
|
|
&mut self, invoc: &Invocation, eager_expansion_root: ExpnId, force: bool
|
|
) -> Result<InvocationRes, Indeterminate>;
|
|
|
|
fn check_unused_macros(&mut self);
|
|
|
|
fn has_derives(&self, expn_id: ExpnId, derives: SpecialDerives) -> bool;
|
|
fn add_derives(&mut self, expn_id: ExpnId, derives: SpecialDerives);
|
|
}
|
|
|
|
#[derive(Clone)]
|
|
pub struct ModuleData {
|
|
pub mod_path: Vec<ast::Ident>,
|
|
pub directory: PathBuf,
|
|
}
|
|
|
|
#[derive(Clone)]
|
|
pub struct ExpansionData {
|
|
pub id: ExpnId,
|
|
pub depth: usize,
|
|
pub module: Rc<ModuleData>,
|
|
pub directory_ownership: DirectoryOwnership,
|
|
pub prior_type_ascription: Option<(Span, bool)>,
|
|
}
|
|
|
|
/// One of these is made during expansion and incrementally updated as we go;
|
|
/// when a macro expansion occurs, the resulting nodes have the `backtrace()
|
|
/// -> expn_data` of their expansion context stored into their span.
|
|
pub struct ExtCtxt<'a> {
|
|
pub parse_sess: &'a ParseSess,
|
|
pub ecfg: expand::ExpansionConfig<'a>,
|
|
pub root_path: PathBuf,
|
|
pub resolver: &'a mut dyn Resolver,
|
|
pub current_expansion: ExpansionData,
|
|
pub expansions: FxHashMap<Span, Vec<String>>,
|
|
}
|
|
|
|
impl<'a> ExtCtxt<'a> {
|
|
pub fn new(parse_sess: &'a ParseSess,
|
|
ecfg: expand::ExpansionConfig<'a>,
|
|
resolver: &'a mut dyn Resolver)
|
|
-> ExtCtxt<'a> {
|
|
ExtCtxt {
|
|
parse_sess,
|
|
ecfg,
|
|
root_path: PathBuf::new(),
|
|
resolver,
|
|
current_expansion: ExpansionData {
|
|
id: ExpnId::root(),
|
|
depth: 0,
|
|
module: Rc::new(ModuleData { mod_path: Vec::new(), directory: PathBuf::new() }),
|
|
directory_ownership: DirectoryOwnership::Owned { relative: None },
|
|
prior_type_ascription: None,
|
|
},
|
|
expansions: FxHashMap::default(),
|
|
}
|
|
}
|
|
|
|
/// Returns a `Folder` for deeply expanding all macros in an AST node.
|
|
pub fn expander<'b>(&'b mut self) -> expand::MacroExpander<'b, 'a> {
|
|
expand::MacroExpander::new(self, false)
|
|
}
|
|
|
|
/// Returns a `Folder` that deeply expands all macros and assigns all `NodeId`s in an AST node.
|
|
/// Once `NodeId`s are assigned, the node may not be expanded, removed, or otherwise modified.
|
|
pub fn monotonic_expander<'b>(&'b mut self) -> expand::MacroExpander<'b, 'a> {
|
|
expand::MacroExpander::new(self, true)
|
|
}
|
|
pub fn new_parser_from_tts(&self, stream: TokenStream) -> parser::Parser<'a> {
|
|
parse::stream_to_parser(self.parse_sess, stream, MACRO_ARGUMENTS)
|
|
}
|
|
pub fn source_map(&self) -> &'a SourceMap { self.parse_sess.source_map() }
|
|
pub fn parse_sess(&self) -> &'a ParseSess { self.parse_sess }
|
|
pub fn cfg(&self) -> &ast::CrateConfig { &self.parse_sess.config }
|
|
pub fn call_site(&self) -> Span {
|
|
self.current_expansion.id.expn_data().call_site
|
|
}
|
|
|
|
/// Equivalent of `Span::def_site` from the proc macro API,
|
|
/// except that the location is taken from the span passed as an argument.
|
|
pub fn with_def_site_ctxt(&self, span: Span) -> Span {
|
|
span.with_def_site_ctxt(self.current_expansion.id)
|
|
}
|
|
|
|
/// Equivalent of `Span::call_site` from the proc macro API,
|
|
/// except that the location is taken from the span passed as an argument.
|
|
pub fn with_call_site_ctxt(&self, span: Span) -> Span {
|
|
span.with_call_site_ctxt(self.current_expansion.id)
|
|
}
|
|
|
|
/// Equivalent of `Span::mixed_site` from the proc macro API,
|
|
/// except that the location is taken from the span passed as an argument.
|
|
pub fn with_mixed_site_ctxt(&self, span: Span) -> Span {
|
|
span.with_mixed_site_ctxt(self.current_expansion.id)
|
|
}
|
|
|
|
/// Returns span for the macro which originally caused the current expansion to happen.
|
|
///
|
|
/// Stops backtracing at include! boundary.
|
|
pub fn expansion_cause(&self) -> Option<Span> {
|
|
let mut expn_id = self.current_expansion.id;
|
|
let mut last_macro = None;
|
|
loop {
|
|
let expn_data = expn_id.expn_data();
|
|
// Stop going up the backtrace once include! is encountered
|
|
if expn_data.is_root() || expn_data.kind.descr() == sym::include {
|
|
break;
|
|
}
|
|
expn_id = expn_data.call_site.ctxt().outer_expn();
|
|
last_macro = Some(expn_data.call_site);
|
|
}
|
|
last_macro
|
|
}
|
|
|
|
pub fn struct_span_warn<S: Into<MultiSpan>>(&self,
|
|
sp: S,
|
|
msg: &str)
|
|
-> DiagnosticBuilder<'a> {
|
|
self.parse_sess.span_diagnostic.struct_span_warn(sp, msg)
|
|
}
|
|
pub fn struct_span_err<S: Into<MultiSpan>>(&self,
|
|
sp: S,
|
|
msg: &str)
|
|
-> DiagnosticBuilder<'a> {
|
|
self.parse_sess.span_diagnostic.struct_span_err(sp, msg)
|
|
}
|
|
pub fn struct_span_fatal<S: Into<MultiSpan>>(&self,
|
|
sp: S,
|
|
msg: &str)
|
|
-> DiagnosticBuilder<'a> {
|
|
self.parse_sess.span_diagnostic.struct_span_fatal(sp, msg)
|
|
}
|
|
|
|
/// Emit `msg` attached to `sp`, and stop compilation immediately.
|
|
///
|
|
/// `span_err` should be strongly preferred where-ever possible:
|
|
/// this should *only* be used when:
|
|
///
|
|
/// - continuing has a high risk of flow-on errors (e.g., errors in
|
|
/// declaring a macro would cause all uses of that macro to
|
|
/// complain about "undefined macro"), or
|
|
/// - there is literally nothing else that can be done (however,
|
|
/// in most cases one can construct a dummy expression/item to
|
|
/// substitute; we never hit resolve/type-checking so the dummy
|
|
/// value doesn't have to match anything)
|
|
pub fn span_fatal<S: Into<MultiSpan>>(&self, sp: S, msg: &str) -> ! {
|
|
self.parse_sess.span_diagnostic.span_fatal(sp, msg).raise();
|
|
}
|
|
|
|
/// Emit `msg` attached to `sp`, without immediately stopping
|
|
/// compilation.
|
|
///
|
|
/// Compilation will be stopped in the near future (at the end of
|
|
/// the macro expansion phase).
|
|
pub fn span_err<S: Into<MultiSpan>>(&self, sp: S, msg: &str) {
|
|
self.parse_sess.span_diagnostic.span_err(sp, msg);
|
|
}
|
|
pub fn span_err_with_code<S: Into<MultiSpan>>(&self, sp: S, msg: &str, code: DiagnosticId) {
|
|
self.parse_sess.span_diagnostic.span_err_with_code(sp, msg, code);
|
|
}
|
|
pub fn span_warn<S: Into<MultiSpan>>(&self, sp: S, msg: &str) {
|
|
self.parse_sess.span_diagnostic.span_warn(sp, msg);
|
|
}
|
|
pub fn span_bug<S: Into<MultiSpan>>(&self, sp: S, msg: &str) -> ! {
|
|
self.parse_sess.span_diagnostic.span_bug(sp, msg);
|
|
}
|
|
pub fn trace_macros_diag(&mut self) {
|
|
for (sp, notes) in self.expansions.iter() {
|
|
let mut db = self.parse_sess.span_diagnostic.span_note_diag(*sp, "trace_macro");
|
|
for note in notes {
|
|
db.note(note);
|
|
}
|
|
db.emit();
|
|
}
|
|
// Fixme: does this result in errors?
|
|
self.expansions.clear();
|
|
}
|
|
pub fn bug(&self, msg: &str) -> ! {
|
|
self.parse_sess.span_diagnostic.bug(msg);
|
|
}
|
|
pub fn trace_macros(&self) -> bool {
|
|
self.ecfg.trace_mac
|
|
}
|
|
pub fn set_trace_macros(&mut self, x: bool) {
|
|
self.ecfg.trace_mac = x
|
|
}
|
|
pub fn ident_of(&self, st: &str, sp: Span) -> ast::Ident {
|
|
ast::Ident::from_str_and_span(st, sp)
|
|
}
|
|
pub fn std_path(&self, components: &[Symbol]) -> Vec<ast::Ident> {
|
|
let def_site = self.with_def_site_ctxt(DUMMY_SP);
|
|
iter::once(Ident::new(kw::DollarCrate, def_site))
|
|
.chain(components.iter().map(|&s| Ident::with_dummy_span(s)))
|
|
.collect()
|
|
}
|
|
pub fn name_of(&self, st: &str) -> ast::Name {
|
|
Symbol::intern(st)
|
|
}
|
|
|
|
pub fn check_unused_macros(&mut self) {
|
|
self.resolver.check_unused_macros();
|
|
}
|
|
|
|
/// Resolves a path mentioned inside Rust code.
|
|
///
|
|
/// This unifies the logic used for resolving `include_X!`, and `#[doc(include)]` file paths.
|
|
///
|
|
/// Returns an absolute path to the file that `path` refers to.
|
|
pub fn resolve_path(
|
|
&self,
|
|
path: impl Into<PathBuf>,
|
|
span: Span,
|
|
) -> Result<PathBuf, DiagnosticBuilder<'a>> {
|
|
let path = path.into();
|
|
|
|
// Relative paths are resolved relative to the file in which they are found
|
|
// after macro expansion (that is, they are unhygienic).
|
|
if !path.is_absolute() {
|
|
let callsite = span.source_callsite();
|
|
let mut result = match self.source_map().span_to_unmapped_path(callsite) {
|
|
FileName::Real(path) => path,
|
|
FileName::DocTest(path, _) => path,
|
|
other => return Err(self.struct_span_err(
|
|
span,
|
|
&format!("cannot resolve relative path in non-file source `{}`", other),
|
|
)),
|
|
};
|
|
result.pop();
|
|
result.push(path);
|
|
Ok(result)
|
|
} else {
|
|
Ok(path)
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Extracts a string literal from the macro expanded version of `expr`,
|
|
/// emitting `err_msg` if `expr` is not a string literal. This does not stop
|
|
/// compilation on error, merely emits a non-fatal error and returns `None`.
|
|
pub fn expr_to_spanned_string<'a>(
|
|
cx: &'a mut ExtCtxt<'_>,
|
|
expr: P<ast::Expr>,
|
|
err_msg: &str,
|
|
) -> Result<(Symbol, ast::StrStyle, Span), Option<DiagnosticBuilder<'a>>> {
|
|
// Perform eager expansion on the expression.
|
|
// We want to be able to handle e.g., `concat!("foo", "bar")`.
|
|
let expr = cx.expander().fully_expand_fragment(AstFragment::Expr(expr)).make_expr();
|
|
|
|
Err(match expr.kind {
|
|
ast::ExprKind::Lit(ref l) => match l.kind {
|
|
ast::LitKind::Str(s, style) => return Ok((s, style, expr.span)),
|
|
ast::LitKind::Err(_) => None,
|
|
_ => Some(cx.struct_span_err(l.span, err_msg))
|
|
},
|
|
ast::ExprKind::Err => None,
|
|
_ => Some(cx.struct_span_err(expr.span, err_msg))
|
|
})
|
|
}
|
|
|
|
pub fn expr_to_string(cx: &mut ExtCtxt<'_>, expr: P<ast::Expr>, err_msg: &str)
|
|
-> Option<(Symbol, ast::StrStyle)> {
|
|
expr_to_spanned_string(cx, expr, err_msg)
|
|
.map_err(|err| err.map(|mut err| err.emit()))
|
|
.ok()
|
|
.map(|(symbol, style, _)| (symbol, style))
|
|
}
|
|
|
|
/// Non-fatally assert that `tts` is empty. Note that this function
|
|
/// returns even when `tts` is non-empty, macros that *need* to stop
|
|
/// compilation should call
|
|
/// `cx.parse_sess.span_diagnostic.abort_if_errors()` (this should be
|
|
/// done as rarely as possible).
|
|
pub fn check_zero_tts(cx: &ExtCtxt<'_>,
|
|
sp: Span,
|
|
tts: TokenStream,
|
|
name: &str) {
|
|
if !tts.is_empty() {
|
|
cx.span_err(sp, &format!("{} takes no arguments", name));
|
|
}
|
|
}
|
|
|
|
/// Interpreting `tts` as a comma-separated sequence of expressions,
|
|
/// expect exactly one string literal, or emit an error and return `None`.
|
|
pub fn get_single_str_from_tts(cx: &mut ExtCtxt<'_>,
|
|
sp: Span,
|
|
tts: TokenStream,
|
|
name: &str)
|
|
-> Option<String> {
|
|
let mut p = cx.new_parser_from_tts(tts);
|
|
if p.token == token::Eof {
|
|
cx.span_err(sp, &format!("{} takes 1 argument", name));
|
|
return None
|
|
}
|
|
let ret = panictry!(p.parse_expr());
|
|
let _ = p.eat(&token::Comma);
|
|
|
|
if p.token != token::Eof {
|
|
cx.span_err(sp, &format!("{} takes 1 argument", name));
|
|
}
|
|
expr_to_string(cx, ret, "argument must be a string literal").map(|(s, _)| {
|
|
s.to_string()
|
|
})
|
|
}
|
|
|
|
/// Extracts comma-separated expressions from `tts`. If there is a
|
|
/// parsing error, emit a non-fatal error and return `None`.
|
|
pub fn get_exprs_from_tts(cx: &mut ExtCtxt<'_>,
|
|
sp: Span,
|
|
tts: TokenStream) -> Option<Vec<P<ast::Expr>>> {
|
|
let mut p = cx.new_parser_from_tts(tts);
|
|
let mut es = Vec::new();
|
|
while p.token != token::Eof {
|
|
let expr = panictry!(p.parse_expr());
|
|
|
|
// Perform eager expansion on the expression.
|
|
// We want to be able to handle e.g., `concat!("foo", "bar")`.
|
|
let expr = cx.expander().fully_expand_fragment(AstFragment::Expr(expr)).make_expr();
|
|
|
|
es.push(expr);
|
|
if p.eat(&token::Comma) {
|
|
continue;
|
|
}
|
|
if p.token != token::Eof {
|
|
cx.span_err(sp, "expected token: `,`");
|
|
return None;
|
|
}
|
|
}
|
|
Some(es)
|
|
}
|