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Diffstat (limited to 'src/libsyntax_expand/build.rs')
| -rw-r--r-- | src/libsyntax_expand/build.rs | 640 |
1 files changed, 640 insertions, 0 deletions
diff --git a/src/libsyntax_expand/build.rs b/src/libsyntax_expand/build.rs new file mode 100644 index 00000000000..105ffe3ee8a --- /dev/null +++ b/src/libsyntax_expand/build.rs @@ -0,0 +1,640 @@ +use crate::base::ExtCtxt; + +use syntax::ast::{self, Ident, Expr, BlockCheckMode, UnOp, PatKind}; +use syntax::attr; +use syntax::source_map::{respan, Spanned}; +use syntax::ptr::P; +use syntax::symbol::{kw, sym, Symbol}; +use syntax::ThinVec; + +use syntax_pos::{Pos, Span}; + +impl<'a> ExtCtxt<'a> { + pub fn path(&self, span: Span, strs: Vec<ast::Ident> ) -> ast::Path { + self.path_all(span, false, strs, vec![]) + } + pub fn path_ident(&self, span: Span, id: ast::Ident) -> ast::Path { + self.path(span, vec![id]) + } + pub fn path_global(&self, span: Span, strs: Vec<ast::Ident> ) -> ast::Path { + self.path_all(span, true, strs, vec![]) + } + pub fn path_all(&self, + span: Span, + global: bool, + mut idents: Vec<ast::Ident> , + args: Vec<ast::GenericArg>) + -> ast::Path { + assert!(!idents.is_empty()); + let add_root = global && !idents[0].is_path_segment_keyword(); + let mut segments = Vec::with_capacity(idents.len() + add_root as usize); + if add_root { + segments.push(ast::PathSegment::path_root(span)); + } + let last_ident = idents.pop().unwrap(); + segments.extend(idents.into_iter().map(|ident| { + ast::PathSegment::from_ident(ident.with_span_pos(span)) + })); + let args = if !args.is_empty() { + ast::AngleBracketedArgs { args, constraints: Vec::new(), span }.into() + } else { + None + }; + segments.push(ast::PathSegment { + ident: last_ident.with_span_pos(span), + id: ast::DUMMY_NODE_ID, + args, + }); + ast::Path { span, segments } + } + + pub fn ty_mt(&self, ty: P<ast::Ty>, mutbl: ast::Mutability) -> ast::MutTy { + ast::MutTy { + ty, + mutbl, + } + } + + pub fn ty(&self, span: Span, kind: ast::TyKind) -> P<ast::Ty> { + P(ast::Ty { + id: ast::DUMMY_NODE_ID, + span, + kind, + }) + } + + pub fn ty_path(&self, path: ast::Path) -> P<ast::Ty> { + self.ty(path.span, ast::TyKind::Path(None, path)) + } + + // Might need to take bounds as an argument in the future, if you ever want + // to generate a bounded existential trait type. + pub fn ty_ident(&self, span: Span, ident: ast::Ident) + -> P<ast::Ty> { + self.ty_path(self.path_ident(span, ident)) + } + + pub fn anon_const(&self, span: Span, kind: ast::ExprKind) -> ast::AnonConst { + ast::AnonConst { + id: ast::DUMMY_NODE_ID, + value: P(ast::Expr { + id: ast::DUMMY_NODE_ID, + kind, + span, + attrs: ThinVec::new(), + }) + } + } + + pub fn const_ident(&self, span: Span, ident: ast::Ident) -> ast::AnonConst { + self.anon_const(span, ast::ExprKind::Path(None, self.path_ident(span, ident))) + } + + pub fn ty_rptr(&self, + span: Span, + ty: P<ast::Ty>, + lifetime: Option<ast::Lifetime>, + mutbl: ast::Mutability) + -> P<ast::Ty> { + self.ty(span, + ast::TyKind::Rptr(lifetime, self.ty_mt(ty, mutbl))) + } + + pub fn ty_ptr(&self, + span: Span, + ty: P<ast::Ty>, + mutbl: ast::Mutability) + -> P<ast::Ty> { + self.ty(span, + ast::TyKind::Ptr(self.ty_mt(ty, mutbl))) + } + + pub fn typaram(&self, + span: Span, + ident: ast::Ident, + attrs: Vec<ast::Attribute>, + bounds: ast::GenericBounds, + default: Option<P<ast::Ty>>) -> ast::GenericParam { + ast::GenericParam { + ident: ident.with_span_pos(span), + id: ast::DUMMY_NODE_ID, + attrs: attrs.into(), + bounds, + kind: ast::GenericParamKind::Type { + default, + }, + is_placeholder: false + } + } + + pub fn trait_ref(&self, path: ast::Path) -> ast::TraitRef { + ast::TraitRef { + path, + ref_id: ast::DUMMY_NODE_ID, + } + } + + pub fn poly_trait_ref(&self, span: Span, path: ast::Path) -> ast::PolyTraitRef { + ast::PolyTraitRef { + bound_generic_params: Vec::new(), + trait_ref: self.trait_ref(path), + span, + } + } + + pub fn trait_bound(&self, path: ast::Path) -> ast::GenericBound { + ast::GenericBound::Trait(self.poly_trait_ref(path.span, path), + ast::TraitBoundModifier::None) + } + + pub fn lifetime(&self, span: Span, ident: ast::Ident) -> ast::Lifetime { + ast::Lifetime { id: ast::DUMMY_NODE_ID, ident: ident.with_span_pos(span) } + } + + pub fn lifetime_def(&self, + span: Span, + ident: ast::Ident, + attrs: Vec<ast::Attribute>, + bounds: ast::GenericBounds) + -> ast::GenericParam { + let lifetime = self.lifetime(span, ident); + ast::GenericParam { + ident: lifetime.ident, + id: lifetime.id, + attrs: attrs.into(), + bounds, + kind: ast::GenericParamKind::Lifetime, + is_placeholder: false + } + } + + pub fn stmt_expr(&self, expr: P<ast::Expr>) -> ast::Stmt { + ast::Stmt { + id: ast::DUMMY_NODE_ID, + span: expr.span, + kind: ast::StmtKind::Expr(expr), + } + } + + pub fn stmt_let(&self, sp: Span, mutbl: bool, ident: ast::Ident, + ex: P<ast::Expr>) -> ast::Stmt { + let pat = if mutbl { + let binding_mode = ast::BindingMode::ByValue(ast::Mutability::Mutable); + self.pat_ident_binding_mode(sp, ident, binding_mode) + } else { + self.pat_ident(sp, ident) + }; + let local = P(ast::Local { + pat, + ty: None, + init: Some(ex), + id: ast::DUMMY_NODE_ID, + span: sp, + attrs: ThinVec::new(), + }); + ast::Stmt { + id: ast::DUMMY_NODE_ID, + kind: ast::StmtKind::Local(local), + span: sp, + } + } + + // Generates `let _: Type;`, which is usually used for type assertions. + pub fn stmt_let_type_only(&self, span: Span, ty: P<ast::Ty>) -> ast::Stmt { + let local = P(ast::Local { + pat: self.pat_wild(span), + ty: Some(ty), + init: None, + id: ast::DUMMY_NODE_ID, + span, + attrs: ThinVec::new(), + }); + ast::Stmt { + id: ast::DUMMY_NODE_ID, + kind: ast::StmtKind::Local(local), + span, + } + } + + pub fn stmt_item(&self, sp: Span, item: P<ast::Item>) -> ast::Stmt { + ast::Stmt { + id: ast::DUMMY_NODE_ID, + kind: ast::StmtKind::Item(item), + span: sp, + } + } + + pub fn block_expr(&self, expr: P<ast::Expr>) -> P<ast::Block> { + self.block(expr.span, vec![ast::Stmt { + id: ast::DUMMY_NODE_ID, + span: expr.span, + kind: ast::StmtKind::Expr(expr), + }]) + } + pub fn block(&self, span: Span, stmts: Vec<ast::Stmt>) -> P<ast::Block> { + P(ast::Block { + stmts, + id: ast::DUMMY_NODE_ID, + rules: BlockCheckMode::Default, + span, + }) + } + + pub fn expr(&self, span: Span, kind: ast::ExprKind) -> P<ast::Expr> { + P(ast::Expr { + id: ast::DUMMY_NODE_ID, + kind, + span, + attrs: ThinVec::new(), + }) + } + + pub fn expr_path(&self, path: ast::Path) -> P<ast::Expr> { + self.expr(path.span, ast::ExprKind::Path(None, path)) + } + + pub fn expr_ident(&self, span: Span, id: ast::Ident) -> P<ast::Expr> { + self.expr_path(self.path_ident(span, id)) + } + pub fn expr_self(&self, span: Span) -> P<ast::Expr> { + self.expr_ident(span, Ident::with_dummy_span(kw::SelfLower)) + } + + pub fn expr_binary(&self, sp: Span, op: ast::BinOpKind, + lhs: P<ast::Expr>, rhs: P<ast::Expr>) -> P<ast::Expr> { + self.expr(sp, ast::ExprKind::Binary(Spanned { node: op, span: sp }, lhs, rhs)) + } + + pub fn expr_deref(&self, sp: Span, e: P<ast::Expr>) -> P<ast::Expr> { + self.expr(sp, ast::ExprKind::Unary(UnOp::Deref, e)) + } + + pub fn expr_addr_of(&self, sp: Span, e: P<ast::Expr>) -> P<ast::Expr> { + self.expr(sp, ast::ExprKind::AddrOf(ast::Mutability::Immutable, e)) + } + + pub fn expr_call( + &self, span: Span, expr: P<ast::Expr>, args: Vec<P<ast::Expr>>, + ) -> P<ast::Expr> { + self.expr(span, ast::ExprKind::Call(expr, args)) + } + pub fn expr_call_ident(&self, span: Span, id: ast::Ident, + args: Vec<P<ast::Expr>>) -> P<ast::Expr> { + self.expr(span, ast::ExprKind::Call(self.expr_ident(span, id), args)) + } + pub fn expr_call_global(&self, sp: Span, fn_path: Vec<ast::Ident> , + args: Vec<P<ast::Expr>> ) -> P<ast::Expr> { + let pathexpr = self.expr_path(self.path_global(sp, fn_path)); + self.expr_call(sp, pathexpr, args) + } + pub fn expr_method_call(&self, span: Span, + expr: P<ast::Expr>, + ident: ast::Ident, + mut args: Vec<P<ast::Expr>> ) -> P<ast::Expr> { + args.insert(0, expr); + let segment = ast::PathSegment::from_ident(ident.with_span_pos(span)); + self.expr(span, ast::ExprKind::MethodCall(segment, args)) + } + pub fn expr_block(&self, b: P<ast::Block>) -> P<ast::Expr> { + self.expr(b.span, ast::ExprKind::Block(b, None)) + } + pub fn field_imm(&self, span: Span, ident: Ident, e: P<ast::Expr>) -> ast::Field { + ast::Field { + ident: ident.with_span_pos(span), + expr: e, + span, + is_shorthand: false, + attrs: ThinVec::new(), + id: ast::DUMMY_NODE_ID, + is_placeholder: false, + } + } + pub fn expr_struct( + &self, span: Span, path: ast::Path, fields: Vec<ast::Field> + ) -> P<ast::Expr> { + self.expr(span, ast::ExprKind::Struct(path, fields, None)) + } + pub fn expr_struct_ident(&self, span: Span, + id: ast::Ident, fields: Vec<ast::Field>) -> P<ast::Expr> { + self.expr_struct(span, self.path_ident(span, id), fields) + } + + pub fn expr_lit(&self, span: Span, lit_kind: ast::LitKind) -> P<ast::Expr> { + let lit = ast::Lit::from_lit_kind(lit_kind, span); + self.expr(span, ast::ExprKind::Lit(lit)) + } + pub fn expr_usize(&self, span: Span, i: usize) -> P<ast::Expr> { + self.expr_lit(span, ast::LitKind::Int(i as u128, + ast::LitIntType::Unsigned(ast::UintTy::Usize))) + } + pub fn expr_u32(&self, sp: Span, u: u32) -> P<ast::Expr> { + self.expr_lit(sp, ast::LitKind::Int(u as u128, + ast::LitIntType::Unsigned(ast::UintTy::U32))) + } + pub fn expr_bool(&self, sp: Span, value: bool) -> P<ast::Expr> { + self.expr_lit(sp, ast::LitKind::Bool(value)) + } + + pub fn expr_vec(&self, sp: Span, exprs: Vec<P<ast::Expr>>) -> P<ast::Expr> { + self.expr(sp, ast::ExprKind::Array(exprs)) + } + pub fn expr_vec_slice(&self, sp: Span, exprs: Vec<P<ast::Expr>>) -> P<ast::Expr> { + self.expr_addr_of(sp, self.expr_vec(sp, exprs)) + } + pub fn expr_str(&self, sp: Span, s: Symbol) -> P<ast::Expr> { + self.expr_lit(sp, ast::LitKind::Str(s, ast::StrStyle::Cooked)) + } + + pub fn expr_cast(&self, sp: Span, expr: P<ast::Expr>, ty: P<ast::Ty>) -> P<ast::Expr> { + self.expr(sp, ast::ExprKind::Cast(expr, ty)) + } + + pub fn expr_some(&self, sp: Span, expr: P<ast::Expr>) -> P<ast::Expr> { + let some = self.std_path(&[sym::option, sym::Option, sym::Some]); + self.expr_call_global(sp, some, vec![expr]) + } + + pub fn expr_tuple(&self, sp: Span, exprs: Vec<P<ast::Expr>>) -> P<ast::Expr> { + self.expr(sp, ast::ExprKind::Tup(exprs)) + } + + pub fn expr_fail(&self, span: Span, msg: Symbol) -> P<ast::Expr> { + let loc = self.source_map().lookup_char_pos(span.lo()); + let expr_file = self.expr_str(span, Symbol::intern(&loc.file.name.to_string())); + let expr_line = self.expr_u32(span, loc.line as u32); + let expr_col = self.expr_u32(span, loc.col.to_usize() as u32 + 1); + let expr_loc_tuple = self.expr_tuple(span, vec![expr_file, expr_line, expr_col]); + let expr_loc_ptr = self.expr_addr_of(span, expr_loc_tuple); + self.expr_call_global( + span, + [sym::std, sym::rt, sym::begin_panic].iter().map(|s| Ident::new(*s, span)).collect(), + vec![ + self.expr_str(span, msg), + expr_loc_ptr]) + } + + pub fn expr_unreachable(&self, span: Span) -> P<ast::Expr> { + self.expr_fail(span, Symbol::intern("internal error: entered unreachable code")) + } + + pub fn expr_ok(&self, sp: Span, expr: P<ast::Expr>) -> P<ast::Expr> { + let ok = self.std_path(&[sym::result, sym::Result, sym::Ok]); + self.expr_call_global(sp, ok, vec![expr]) + } + + pub fn expr_try(&self, sp: Span, head: P<ast::Expr>) -> P<ast::Expr> { + let ok = self.std_path(&[sym::result, sym::Result, sym::Ok]); + let ok_path = self.path_global(sp, ok); + let err = self.std_path(&[sym::result, sym::Result, sym::Err]); + let err_path = self.path_global(sp, err); + + let binding_variable = self.ident_of("__try_var", sp); + let binding_pat = self.pat_ident(sp, binding_variable); + let binding_expr = self.expr_ident(sp, binding_variable); + + // `Ok(__try_var)` pattern + let ok_pat = self.pat_tuple_struct(sp, ok_path, vec![binding_pat.clone()]); + + // `Err(__try_var)` (pattern and expression respectively) + let err_pat = self.pat_tuple_struct(sp, err_path.clone(), vec![binding_pat]); + let err_inner_expr = self.expr_call(sp, self.expr_path(err_path), + vec![binding_expr.clone()]); + // `return Err(__try_var)` + let err_expr = self.expr(sp, ast::ExprKind::Ret(Some(err_inner_expr))); + + // `Ok(__try_var) => __try_var` + let ok_arm = self.arm(sp, ok_pat, binding_expr); + // `Err(__try_var) => return Err(__try_var)` + let err_arm = self.arm(sp, err_pat, err_expr); + + // `match head { Ok() => ..., Err() => ... }` + self.expr_match(sp, head, vec![ok_arm, err_arm]) + } + + + pub fn pat(&self, span: Span, kind: PatKind) -> P<ast::Pat> { + P(ast::Pat { id: ast::DUMMY_NODE_ID, kind, span }) + } + pub fn pat_wild(&self, span: Span) -> P<ast::Pat> { + self.pat(span, PatKind::Wild) + } + pub fn pat_lit(&self, span: Span, expr: P<ast::Expr>) -> P<ast::Pat> { + self.pat(span, PatKind::Lit(expr)) + } + pub fn pat_ident(&self, span: Span, ident: ast::Ident) -> P<ast::Pat> { + let binding_mode = ast::BindingMode::ByValue(ast::Mutability::Immutable); + self.pat_ident_binding_mode(span, ident, binding_mode) + } + + pub fn pat_ident_binding_mode(&self, + span: Span, + ident: ast::Ident, + bm: ast::BindingMode) -> P<ast::Pat> { + let pat = PatKind::Ident(bm, ident.with_span_pos(span), None); + self.pat(span, pat) + } + pub fn pat_path(&self, span: Span, path: ast::Path) -> P<ast::Pat> { + self.pat(span, PatKind::Path(None, path)) + } + pub fn pat_tuple_struct(&self, span: Span, path: ast::Path, + subpats: Vec<P<ast::Pat>>) -> P<ast::Pat> { + self.pat(span, PatKind::TupleStruct(path, subpats)) + } + pub fn pat_struct(&self, span: Span, path: ast::Path, + field_pats: Vec<ast::FieldPat>) -> P<ast::Pat> { + self.pat(span, PatKind::Struct(path, field_pats, false)) + } + pub fn pat_tuple(&self, span: Span, pats: Vec<P<ast::Pat>>) -> P<ast::Pat> { + self.pat(span, PatKind::Tuple(pats)) + } + + pub fn pat_some(&self, span: Span, pat: P<ast::Pat>) -> P<ast::Pat> { + let some = self.std_path(&[sym::option, sym::Option, sym::Some]); + let path = self.path_global(span, some); + self.pat_tuple_struct(span, path, vec![pat]) + } + + pub fn pat_none(&self, span: Span) -> P<ast::Pat> { + let some = self.std_path(&[sym::option, sym::Option, sym::None]); + let path = self.path_global(span, some); + self.pat_path(span, path) + } + + pub fn pat_ok(&self, span: Span, pat: P<ast::Pat>) -> P<ast::Pat> { + let some = self.std_path(&[sym::result, sym::Result, sym::Ok]); + let path = self.path_global(span, some); + self.pat_tuple_struct(span, path, vec![pat]) + } + + pub fn pat_err(&self, span: Span, pat: P<ast::Pat>) -> P<ast::Pat> { + let some = self.std_path(&[sym::result, sym::Result, sym::Err]); + let path = self.path_global(span, some); + self.pat_tuple_struct(span, path, vec![pat]) + } + + pub fn arm(&self, span: Span, pat: P<ast::Pat>, expr: P<ast::Expr>) -> ast::Arm { + ast::Arm { + attrs: vec![], + pat, + guard: None, + body: expr, + span, + id: ast::DUMMY_NODE_ID, + is_placeholder: false, + } + } + + pub fn arm_unreachable(&self, span: Span) -> ast::Arm { + self.arm(span, self.pat_wild(span), self.expr_unreachable(span)) + } + + pub fn expr_match(&self, span: Span, arg: P<ast::Expr>, arms: Vec<ast::Arm>) -> P<Expr> { + self.expr(span, ast::ExprKind::Match(arg, arms)) + } + + pub fn expr_if(&self, span: Span, cond: P<ast::Expr>, + then: P<ast::Expr>, els: Option<P<ast::Expr>>) -> P<ast::Expr> { + let els = els.map(|x| self.expr_block(self.block_expr(x))); + self.expr(span, ast::ExprKind::If(cond, self.block_expr(then), els)) + } + + pub fn lambda_fn_decl(&self, + span: Span, + fn_decl: P<ast::FnDecl>, + body: P<ast::Expr>, + fn_decl_span: Span) // span of the `|...|` part + -> P<ast::Expr> { + self.expr(span, ast::ExprKind::Closure(ast::CaptureBy::Ref, + ast::IsAsync::NotAsync, + ast::Movability::Movable, + fn_decl, + body, + fn_decl_span)) + } + + pub fn lambda(&self, + span: Span, + ids: Vec<ast::Ident>, + body: P<ast::Expr>) + -> P<ast::Expr> { + let fn_decl = self.fn_decl( + ids.iter().map(|id| self.param(span, *id, self.ty(span, ast::TyKind::Infer))).collect(), + ast::FunctionRetTy::Default(span)); + + // FIXME -- We are using `span` as the span of the `|...|` + // part of the lambda, but it probably (maybe?) corresponds to + // the entire lambda body. Probably we should extend the API + // here, but that's not entirely clear. + self.expr(span, ast::ExprKind::Closure(ast::CaptureBy::Ref, + ast::IsAsync::NotAsync, + ast::Movability::Movable, + fn_decl, + body, + span)) + } + + pub fn lambda0(&self, span: Span, body: P<ast::Expr>) -> P<ast::Expr> { + self.lambda(span, Vec::new(), body) + } + + pub fn lambda1(&self, span: Span, body: P<ast::Expr>, ident: ast::Ident) -> P<ast::Expr> { + self.lambda(span, vec![ident], body) + } + + pub fn lambda_stmts_1(&self, span: Span, stmts: Vec<ast::Stmt>, + ident: ast::Ident) -> P<ast::Expr> { + self.lambda1(span, self.expr_block(self.block(span, stmts)), ident) + } + + pub fn param(&self, span: Span, ident: ast::Ident, ty: P<ast::Ty>) -> ast::Param { + let arg_pat = self.pat_ident(span, ident); + ast::Param { + attrs: ThinVec::default(), + id: ast::DUMMY_NODE_ID, + pat: arg_pat, + span, + ty, + is_placeholder: false, + } + } + + // FIXME: unused `self` + pub fn fn_decl(&self, inputs: Vec<ast::Param>, output: ast::FunctionRetTy) -> P<ast::FnDecl> { + P(ast::FnDecl { + inputs, + output, + }) + } + + pub fn item(&self, span: Span, name: Ident, + attrs: Vec<ast::Attribute>, kind: ast::ItemKind) -> P<ast::Item> { + // FIXME: Would be nice if our generated code didn't violate + // Rust coding conventions + P(ast::Item { + ident: name, + attrs, + id: ast::DUMMY_NODE_ID, + kind, + vis: respan(span.shrink_to_lo(), ast::VisibilityKind::Inherited), + span, + tokens: None, + }) + } + + pub fn variant(&self, span: Span, ident: Ident, tys: Vec<P<ast::Ty>> ) -> ast::Variant { + let fields: Vec<_> = tys.into_iter().map(|ty| { + ast::StructField { + span: ty.span, + ty, + ident: None, + vis: respan(span.shrink_to_lo(), ast::VisibilityKind::Inherited), + attrs: Vec::new(), + id: ast::DUMMY_NODE_ID, + is_placeholder: false, + } + }).collect(); + + let vdata = if fields.is_empty() { + ast::VariantData::Unit(ast::DUMMY_NODE_ID) + } else { + ast::VariantData::Tuple(fields, ast::DUMMY_NODE_ID) + }; + + ast::Variant { + attrs: Vec::new(), + data: vdata, + disr_expr: None, + id: ast::DUMMY_NODE_ID, + ident, + span, + is_placeholder: false, + } + } + + pub fn item_static(&self, + span: Span, + name: Ident, + ty: P<ast::Ty>, + mutbl: ast::Mutability, + expr: P<ast::Expr>) + -> P<ast::Item> { + self.item(span, name, Vec::new(), ast::ItemKind::Static(ty, mutbl, expr)) + } + + pub fn item_const(&self, + span: Span, + name: Ident, + ty: P<ast::Ty>, + expr: P<ast::Expr>) + -> P<ast::Item> { + self.item(span, name, Vec::new(), ast::ItemKind::Const(ty, expr)) + } + + pub fn attribute(&self, mi: ast::MetaItem) -> ast::Attribute { + attr::mk_attr_outer(mi) + } + + pub fn meta_word(&self, sp: Span, w: ast::Name) -> ast::MetaItem { + attr::mk_word_item(Ident::new(w, sp)) + } +} |