933 lines
31 KiB
Rust
933 lines
31 KiB
Rust
// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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use ast::{blk, crate, expr_, expr_mac, mac_invoc_tt};
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use ast::{item_mac, stmt_, stmt_mac, stmt_expr, stmt_semi};
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use ast::{illegal_ctxt};
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use ast;
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use ast_util::{new_rename, new_mark, resolve};
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use attr;
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use codemap;
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use codemap::{span, ExpnInfo, NameAndSpan};
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use ext::base::*;
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use fold::*;
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use parse;
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use parse::{parse_item_from_source_str};
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use parse::token::{ident_to_str, intern};
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use visit;
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use visit::Visitor;
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use std::vec;
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pub fn expand_expr(extsbox: @mut SyntaxEnv,
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cx: @ExtCtxt,
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e: &expr_,
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s: span,
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fld: @ast_fold,
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orig: @fn(&expr_, span, @ast_fold) -> (expr_, span))
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-> (expr_, span) {
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match *e {
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// expr_mac should really be expr_ext or something; it's the
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// entry-point for all syntax extensions.
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expr_mac(ref mac) => {
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match (*mac).node {
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// Token-tree macros:
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mac_invoc_tt(ref pth, ref tts) => {
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if (pth.idents.len() > 1u) {
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cx.span_fatal(
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pth.span,
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fmt!("expected macro name without module \
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separators"));
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}
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let extname = &pth.idents[0];
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let extnamestr = ident_to_str(extname);
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// leaving explicit deref here to highlight unbox op:
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match (*extsbox).find(&extname.name) {
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None => {
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cx.span_fatal(
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pth.span,
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fmt!("macro undefined: '%s'", extnamestr))
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}
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Some(@SE(NormalTT(SyntaxExpanderTT{
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expander: exp,
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span: exp_sp
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}))) => {
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cx.bt_push(ExpnInfo {
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call_site: s,
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callee: NameAndSpan {
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name: extnamestr,
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span: exp_sp,
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},
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});
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let expanded = match exp(cx, mac.span, *tts) {
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MRExpr(e) => e,
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MRAny(expr_maker,_,_) => expr_maker(),
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_ => {
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cx.span_fatal(
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pth.span,
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fmt!(
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"non-expr macro in expr pos: %s",
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extnamestr
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)
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)
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}
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};
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//keep going, outside-in
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let fully_expanded =
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copy fld.fold_expr(expanded).node;
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cx.bt_pop();
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(fully_expanded, s)
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}
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_ => {
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cx.span_fatal(
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pth.span,
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fmt!("'%s' is not a tt-style macro", extnamestr)
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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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_ => orig(e, s, fld)
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}
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}
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// This is a secondary mechanism for invoking syntax extensions on items:
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// "decorator" attributes, such as #[auto_encode]. These are invoked by an
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// attribute prefixing an item, and are interpreted by feeding the item
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// through the named attribute _as a syntax extension_ and splicing in the
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// resulting item vec into place in favour of the decorator. Note that
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// these do _not_ work for macro extensions, just ItemDecorator ones.
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//
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// NB: there is some redundancy between this and expand_item, below, and
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// they might benefit from some amount of semantic and language-UI merger.
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pub fn expand_mod_items(extsbox: @mut SyntaxEnv,
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cx: @ExtCtxt,
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module_: &ast::_mod,
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fld: @ast_fold,
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orig: @fn(&ast::_mod, @ast_fold) -> ast::_mod)
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-> ast::_mod {
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// Fold the contents first:
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let module_ = orig(module_, fld);
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// For each item, look through the attributes. If any of them are
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// decorated with "item decorators", then use that function to transform
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// the item into a new set of items.
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let new_items = do vec::flat_map(module_.items) |item| {
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do item.attrs.rev_iter().fold(~[*item]) |items, attr| {
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let mname = attr::get_attr_name(attr);
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match (*extsbox).find(&intern(mname)) {
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Some(@SE(ItemDecorator(dec_fn))) => {
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cx.bt_push(ExpnInfo {
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call_site: attr.span,
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callee: NameAndSpan {
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name: mname,
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span: None
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}
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});
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let r = dec_fn(cx, attr.span, attr.node.value, items);
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cx.bt_pop();
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r
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},
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_ => items,
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}
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}
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};
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ast::_mod { items: new_items, ..module_ }
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}
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// eval $e with a new exts frame:
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macro_rules! with_exts_frame (
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($extsboxexpr:expr,$macros_escape:expr,$e:expr) =>
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({let extsbox = $extsboxexpr;
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let oldexts = *extsbox;
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*extsbox = oldexts.push_frame();
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extsbox.insert(intern(special_block_name),
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@BlockInfo(BlockInfo{macros_escape:$macros_escape,pending_renames:@mut ~[]}));
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let result = $e;
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*extsbox = oldexts;
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result
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})
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)
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static special_block_name : &'static str = " block";
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// When we enter a module, record it, for the sake of `module!`
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pub fn expand_item(extsbox: @mut SyntaxEnv,
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cx: @ExtCtxt,
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it: @ast::item,
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fld: @ast_fold,
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orig: @fn(@ast::item, @ast_fold) -> Option<@ast::item>)
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-> Option<@ast::item> {
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// need to do expansion first... it might turn out to be a module.
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let maybe_it = match it.node {
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ast::item_mac(*) => expand_item_mac(extsbox, cx, it, fld),
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_ => Some(it)
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};
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match maybe_it {
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Some(it) => {
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match it.node {
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ast::item_mod(_) | ast::item_foreign_mod(_) => {
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cx.mod_push(it.ident);
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let macro_escape = contains_macro_escape(it.attrs);
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let result = with_exts_frame!(extsbox,macro_escape,orig(it,fld));
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cx.mod_pop();
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result
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}
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_ => orig(it,fld)
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}
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}
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None => None
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}
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}
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// does this attribute list contain "macro_escape" ?
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pub fn contains_macro_escape (attrs: &[ast::attribute]) -> bool {
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attrs.iter().any(|attr| "macro_escape" == attr::get_attr_name(attr))
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}
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// Support for item-position macro invocations, exactly the same
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// logic as for expression-position macro invocations.
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pub fn expand_item_mac(extsbox: @mut SyntaxEnv,
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cx: @ExtCtxt, it: @ast::item,
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fld: @ast_fold)
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-> Option<@ast::item> {
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let (pth, tts) = match it.node {
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item_mac(codemap::spanned { node: mac_invoc_tt(ref pth, ref tts), _}) => {
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(pth, copy *tts)
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}
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_ => cx.span_bug(it.span, "invalid item macro invocation")
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};
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let extname = &pth.idents[0];
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let extnamestr = ident_to_str(extname);
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let expanded = match (*extsbox).find(&extname.name) {
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None => cx.span_fatal(pth.span,
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fmt!("macro undefined: '%s!'", extnamestr)),
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Some(@SE(NormalTT(ref expand))) => {
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if it.ident != parse::token::special_idents::invalid {
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cx.span_fatal(pth.span,
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fmt!("macro %s! expects no ident argument, \
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given '%s'", extnamestr,
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ident_to_str(&it.ident)));
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}
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cx.bt_push(ExpnInfo {
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call_site: it.span,
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callee: NameAndSpan {
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name: extnamestr,
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span: expand.span
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}
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});
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((*expand).expander)(cx, it.span, tts)
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}
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Some(@SE(IdentTT(ref expand))) => {
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if it.ident == parse::token::special_idents::invalid {
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cx.span_fatal(pth.span,
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fmt!("macro %s! expects an ident argument",
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extnamestr));
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}
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cx.bt_push(ExpnInfo {
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call_site: it.span,
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callee: NameAndSpan {
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name: extnamestr,
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span: expand.span
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}
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});
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((*expand).expander)(cx, it.span, it.ident, tts)
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}
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_ => cx.span_fatal(
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it.span, fmt!("%s! is not legal in item position", extnamestr))
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};
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let maybe_it = match expanded {
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MRItem(it) => fld.fold_item(it),
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MRExpr(_) => cx.span_fatal(pth.span,
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fmt!("expr macro in item position: %s", extnamestr)),
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MRAny(_, item_maker, _) => item_maker().chain(|i| {fld.fold_item(i)}),
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MRDef(ref mdef) => {
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insert_macro(*extsbox,intern(mdef.name), @SE((*mdef).ext));
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None
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}
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};
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cx.bt_pop();
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return maybe_it;
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}
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// insert a macro into the innermost frame that doesn't have the
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// macro_escape tag.
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fn insert_macro(exts: SyntaxEnv, name: ast::Name, transformer: @Transformer) {
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let is_non_escaping_block =
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|t : &@Transformer| -> bool{
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match t {
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&@BlockInfo(BlockInfo {macros_escape:false,_}) => true,
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&@BlockInfo(BlockInfo {_}) => false,
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_ => fail!(fmt!("special identifier %? was bound to a non-BlockInfo",
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special_block_name))
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}
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};
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exts.insert_into_frame(name,transformer,intern(special_block_name),
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is_non_escaping_block)
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}
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// expand a stmt
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pub fn expand_stmt(extsbox: @mut SyntaxEnv,
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cx: @ExtCtxt,
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s: &stmt_,
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sp: span,
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fld: @ast_fold,
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orig: @fn(&stmt_, span, @ast_fold)
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-> (Option<stmt_>, span))
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-> (Option<stmt_>, span) {
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let (mac, pth, tts, semi) = match *s {
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stmt_mac(ref mac, semi) => {
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match mac.node {
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mac_invoc_tt(ref pth, ref tts) => {
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(copy *mac, pth, copy *tts, semi)
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}
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}
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}
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_ => return orig(s, sp, fld)
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};
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if (pth.idents.len() > 1u) {
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cx.span_fatal(
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pth.span,
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fmt!("expected macro name without module \
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separators"));
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}
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let extname = &pth.idents[0];
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let extnamestr = ident_to_str(extname);
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let (fully_expanded, sp) = match (*extsbox).find(&extname.name) {
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None =>
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cx.span_fatal(pth.span, fmt!("macro undefined: '%s'", extnamestr)),
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Some(@SE(NormalTT(
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SyntaxExpanderTT{expander: exp, span: exp_sp}))) => {
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cx.bt_push(ExpnInfo {
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call_site: sp,
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callee: NameAndSpan { name: extnamestr, span: exp_sp }
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});
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let expanded = match exp(cx, mac.span, tts) {
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MRExpr(e) =>
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@codemap::spanned { node: stmt_expr(e, cx.next_id()),
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span: e.span},
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MRAny(_,_,stmt_mkr) => stmt_mkr(),
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_ => cx.span_fatal(
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pth.span,
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fmt!("non-stmt macro in stmt pos: %s", extnamestr))
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};
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//keep going, outside-in
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let fully_expanded = match fld.fold_stmt(expanded) {
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Some(stmt) => {
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let fully_expanded = &stmt.node;
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cx.bt_pop();
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copy *fully_expanded
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}
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None => {
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cx.span_fatal(pth.span,
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"macro didn't expand to a statement")
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}
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};
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(fully_expanded, sp)
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}
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_ => {
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cx.span_fatal(pth.span,
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fmt!("'%s' is not a tt-style macro", extnamestr))
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}
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};
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(match fully_expanded {
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stmt_expr(e, stmt_id) if semi => Some(stmt_semi(e, stmt_id)),
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_ => { Some(fully_expanded) } /* might already have a semi */
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}, sp)
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}
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// return a visitor that extracts the pat_ident paths
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// from a given pattern and puts them in a mutable
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// array (passed in to the traversal)
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pub fn new_name_finder() -> @Visitor<@mut ~[ast::ident]> {
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let default_visitor = visit::default_visitor();
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@Visitor{
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visit_pat : |p:@ast::pat,
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(ident_accum, v): (@mut ~[ast::ident], visit::vt<@mut ~[ast::ident]>)| {
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match *p {
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// we found a pat_ident!
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ast::pat{id:_, node: ast::pat_ident(_,ref path,ref inner), span:_} => {
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match path {
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// a path of length one:
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&ast::Path{global: false,idents: [id], span:_,rp:_,types:_} =>
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ident_accum.push(id),
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// I believe these must be enums...
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_ => ()
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}
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// visit optional subpattern of pat_ident:
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for inner.iter().advance |subpat: &@ast::pat| {
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(v.visit_pat)(*subpat, (ident_accum, v))
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}
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}
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// use the default traversal for non-pat_idents
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_ => visit::visit_pat(p,(ident_accum,v))
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}
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},
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.. *default_visitor
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}
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}
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pub fn expand_block(extsbox: @mut SyntaxEnv,
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_cx: @ExtCtxt,
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blk: &blk,
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fld: @ast_fold,
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orig: @fn(&blk, @ast_fold) -> blk)
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-> blk {
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// see note below about treatment of exts table
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with_exts_frame!(extsbox,false,orig(blk,fld))
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}
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// get the (innermost) BlockInfo from an exts stack
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fn get_block_info(exts : SyntaxEnv) -> BlockInfo {
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match exts.find_in_topmost_frame(&intern(special_block_name)) {
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Some(@BlockInfo(bi)) => bi,
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_ => fail!(fmt!("special identifier %? was bound to a non-BlockInfo",
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@" block"))
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}
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}
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|
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// given a mutable list of renames, return a tree-folder that applies those
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// renames.
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fn renames_to_fold(renames : @mut ~[(ast::ident,ast::Name)]) -> @ast_fold {
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let afp = default_ast_fold();
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let f_pre = @AstFoldFns {
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fold_ident: |id,_| {
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// the individual elements are memoized... it would
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// also be possible to memoize on the whole list at once.
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let new_ctxt = renames.iter().fold(id.ctxt,|ctxt,&(from,to)| {
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new_rename(from,to,ctxt)
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});
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ast::ident{name:id.name,ctxt:new_ctxt}
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},
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.. *afp
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};
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make_fold(f_pre)
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}
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// perform a bunch of renames
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fn apply_pending_renames(folder : @ast_fold, stmt : ast::stmt) -> @ast::stmt {
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match folder.fold_stmt(&stmt) {
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Some(s) => s,
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None => fail!(fmt!("renaming of stmt produced None"))
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}
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}
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|
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pub fn new_span(cx: @ExtCtxt, sp: span) -> span {
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/* this discards information in the case of macro-defining macros */
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return span {lo: sp.lo, hi: sp.hi, expn_info: cx.backtrace()};
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}
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// FIXME (#2247): this is a moderately bad kludge to inject some macros into
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// the default compilation environment. It would be much nicer to use
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// a mechanism like syntax_quote to ensure hygiene.
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pub fn std_macros() -> @str {
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return
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@"mod __std_macros {
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#[macro_escape];
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#[doc(hidden)];
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macro_rules! ignore (($($x:tt)*) => (()))
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macro_rules! error (
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|
($arg:expr) => (
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__log(1u32, fmt!( \"%?\", $arg ))
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);
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($( $arg:expr ),+) => (
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__log(1u32, fmt!( $($arg),+ ))
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)
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)
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macro_rules! warn (
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($arg:expr) => (
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__log(2u32, fmt!( \"%?\", $arg ))
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);
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($( $arg:expr ),+) => (
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__log(2u32, fmt!( $($arg),+ ))
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)
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)
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macro_rules! info (
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($arg:expr) => (
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__log(3u32, fmt!( \"%?\", $arg ))
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);
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($( $arg:expr ),+) => (
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__log(3u32, fmt!( $($arg),+ ))
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)
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)
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// conditionally define debug!, but keep it type checking even
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// in non-debug builds.
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macro_rules! __debug (
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($arg:expr) => (
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__log(4u32, fmt!( \"%?\", $arg ))
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);
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($( $arg:expr ),+) => (
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__log(4u32, fmt!( $($arg),+ ))
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)
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)
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#[cfg(debug)]
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#[macro_escape]
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mod debug_macro {
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macro_rules! debug (($($arg:expr),*) => {
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__debug!($($arg),*)
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})
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}
|
|
|
|
#[cfg(not(debug))]
|
|
#[macro_escape]
|
|
mod debug_macro {
|
|
macro_rules! debug (($($arg:expr),*) => {
|
|
if false { __debug!($($arg),*) }
|
|
})
|
|
}
|
|
|
|
macro_rules! fail(
|
|
() => (
|
|
fail!(\"explicit failure\")
|
|
);
|
|
($msg:expr) => (
|
|
::std::sys::FailWithCause::fail_with($msg, file!(), line!())
|
|
);
|
|
($( $arg:expr ),+) => (
|
|
::std::sys::FailWithCause::fail_with(fmt!( $($arg),+ ), file!(), line!())
|
|
)
|
|
)
|
|
|
|
macro_rules! assert(
|
|
($cond:expr) => {
|
|
if !$cond {
|
|
::std::sys::FailWithCause::fail_with(
|
|
~\"assertion failed: \" + stringify!($cond), file!(), line!())
|
|
}
|
|
};
|
|
($cond:expr, $msg:expr) => {
|
|
if !$cond {
|
|
::std::sys::FailWithCause::fail_with($msg, file!(), line!())
|
|
}
|
|
};
|
|
($cond:expr, $( $arg:expr ),+) => {
|
|
if !$cond {
|
|
::std::sys::FailWithCause::fail_with(fmt!( $($arg),+ ), file!(), line!())
|
|
}
|
|
}
|
|
)
|
|
|
|
macro_rules! assert_eq (
|
|
($given:expr , $expected:expr) => (
|
|
{
|
|
let given_val = $given;
|
|
let expected_val = $expected;
|
|
// check both directions of equality....
|
|
if !((given_val == expected_val) && (expected_val == given_val)) {
|
|
fail!(\"assertion failed: `(left == right) && (right == \
|
|
left)` (left: `%?`, right: `%?`)\", given_val, expected_val);
|
|
}
|
|
}
|
|
)
|
|
)
|
|
|
|
macro_rules! assert_approx_eq (
|
|
($given:expr , $expected:expr) => (
|
|
{
|
|
use std::cmp::ApproxEq;
|
|
|
|
let given_val = $given;
|
|
let expected_val = $expected;
|
|
// check both directions of equality....
|
|
if !(
|
|
given_val.approx_eq(&expected_val) &&
|
|
expected_val.approx_eq(&given_val)
|
|
) {
|
|
fail!(\"left: %? does not approximately equal right: %?\",
|
|
given_val, expected_val);
|
|
}
|
|
}
|
|
);
|
|
($given:expr , $expected:expr , $epsilon:expr) => (
|
|
{
|
|
use std::cmp::ApproxEq;
|
|
|
|
let given_val = $given;
|
|
let expected_val = $expected;
|
|
let epsilon_val = $epsilon;
|
|
// check both directions of equality....
|
|
if !(
|
|
given_val.approx_eq_eps(&expected_val, &epsilon_val) &&
|
|
expected_val.approx_eq_eps(&given_val, &epsilon_val)
|
|
) {
|
|
fail!(\"left: %? does not approximately equal right: %? with epsilon: %?\",
|
|
given_val, expected_val, epsilon_val);
|
|
}
|
|
}
|
|
)
|
|
)
|
|
|
|
macro_rules! condition (
|
|
|
|
{ pub $c:ident: $in:ty -> $out:ty; } => {
|
|
|
|
pub mod $c {
|
|
#[allow(non_uppercase_statics)];
|
|
static key: ::std::local_data::Key<
|
|
@::std::condition::Handler<$in, $out>> =
|
|
&::std::local_data::Key;
|
|
|
|
pub static cond :
|
|
::std::condition::Condition<$in,$out> =
|
|
::std::condition::Condition {
|
|
name: stringify!($c),
|
|
key: key
|
|
};
|
|
}
|
|
};
|
|
|
|
{ $c:ident: $in:ty -> $out:ty; } => {
|
|
|
|
// FIXME (#6009): remove mod's `pub` below once variant above lands.
|
|
pub mod $c {
|
|
#[allow(non_uppercase_statics)];
|
|
static key: ::std::local_data::Key<
|
|
@::std::condition::Handler<$in, $out>> =
|
|
&::std::local_data::Key;
|
|
|
|
pub static cond :
|
|
::std::condition::Condition<$in,$out> =
|
|
::std::condition::Condition {
|
|
name: stringify!($c),
|
|
key: key
|
|
};
|
|
}
|
|
}
|
|
)
|
|
|
|
//
|
|
// A scheme-style conditional that helps to improve code clarity in some instances when
|
|
// the `if`, `else if`, and `else` keywords obscure predicates undesirably.
|
|
//
|
|
// # Example
|
|
//
|
|
// ~~~
|
|
// let clamped =
|
|
// if x > mx { mx }
|
|
// else if x < mn { mn }
|
|
// else { x };
|
|
// ~~~
|
|
//
|
|
// Using `cond!`, the above could be written as:
|
|
//
|
|
// ~~~
|
|
// let clamped = cond!(
|
|
// (x > mx) { mx }
|
|
// (x < mn) { mn }
|
|
// _ { x }
|
|
// );
|
|
// ~~~
|
|
//
|
|
// The optional default case is denoted by `_`.
|
|
//
|
|
macro_rules! cond (
|
|
( $(($pred:expr) $body:block)+ _ $default:block ) => (
|
|
$(if $pred $body else)+
|
|
$default
|
|
);
|
|
// for if the default case was ommitted
|
|
( $(($pred:expr) $body:block)+ ) => (
|
|
$(if $pred $body)else+
|
|
);
|
|
)
|
|
|
|
macro_rules! printf (
|
|
($arg:expr) => (
|
|
print(fmt!(\"%?\", $arg))
|
|
);
|
|
($( $arg:expr ),+) => (
|
|
print(fmt!($($arg),+))
|
|
)
|
|
)
|
|
|
|
macro_rules! printfln (
|
|
($arg:expr) => (
|
|
println(fmt!(\"%?\", $arg))
|
|
);
|
|
($( $arg:expr ),+) => (
|
|
println(fmt!($($arg),+))
|
|
)
|
|
)
|
|
}";
|
|
}
|
|
|
|
// add a bunch of macros as though they were placed at the head of the
|
|
// program (ick). This should run before cfg stripping.
|
|
pub fn inject_std_macros(parse_sess: @mut parse::ParseSess,
|
|
cfg: ast::crate_cfg, c: &crate) -> @crate {
|
|
let sm = match parse_item_from_source_str(@"<std-macros>",
|
|
std_macros(),
|
|
copy cfg,
|
|
~[],
|
|
parse_sess) {
|
|
Some(item) => item,
|
|
None => fail!("expected core macros to parse correctly")
|
|
};
|
|
|
|
let injecter = @AstFoldFns {
|
|
fold_mod: |modd, _| {
|
|
// just inject the std macros at the start of the first
|
|
// module in the crate (i.e the crate file itself.)
|
|
let items = vec::append(~[sm], modd.items);
|
|
ast::_mod {
|
|
items: items,
|
|
// FIXME #2543: Bad copy.
|
|
.. copy *modd
|
|
}
|
|
},
|
|
.. *default_ast_fold()
|
|
};
|
|
@make_fold(injecter).fold_crate(c)
|
|
}
|
|
|
|
pub fn expand_crate(parse_sess: @mut parse::ParseSess,
|
|
cfg: ast::crate_cfg, c: &crate) -> @crate {
|
|
// adding *another* layer of indirection here so that the block
|
|
// visitor can swap out one exts table for another for the duration
|
|
// of the block. The cleaner alternative would be to thread the
|
|
// exts table through the fold, but that would require updating
|
|
// every method/element of AstFoldFns in fold.rs.
|
|
let extsbox = @mut syntax_expander_table();
|
|
let afp = default_ast_fold();
|
|
let cx = ExtCtxt::new(parse_sess, copy cfg);
|
|
let f_pre = @AstFoldFns {
|
|
fold_expr: |expr,span,recur|
|
|
expand_expr(extsbox, cx, expr, span, recur, afp.fold_expr),
|
|
fold_mod: |modd,recur|
|
|
expand_mod_items(extsbox, cx, modd, recur, afp.fold_mod),
|
|
fold_item: |item,recur|
|
|
expand_item(extsbox, cx, item, recur, afp.fold_item),
|
|
fold_stmt: |stmt,span,recur|
|
|
expand_stmt(extsbox, cx, stmt, span, recur, afp.fold_stmt),
|
|
fold_block: |blk,recur|
|
|
expand_block(extsbox, cx, blk, recur, afp.fold_block),
|
|
new_span: |a| new_span(cx, a),
|
|
.. *afp};
|
|
let f = make_fold(f_pre);
|
|
|
|
@f.fold_crate(c)
|
|
}
|
|
|
|
// given a function from idents to idents, produce
|
|
// an ast_fold that applies that function:
|
|
pub fn fun_to_ident_folder(f: @fn(ast::ident)->ast::ident) -> @ast_fold{
|
|
let afp = default_ast_fold();
|
|
let f_pre = @AstFoldFns{
|
|
fold_ident : |id, _| f(id),
|
|
.. *afp
|
|
};
|
|
make_fold(f_pre)
|
|
}
|
|
|
|
// update the ctxts in a path to get a rename node
|
|
pub fn new_ident_renamer(from: ast::ident,
|
|
to: ast::Name) ->
|
|
@fn(ast::ident)->ast::ident {
|
|
|id : ast::ident|
|
|
ast::ident{
|
|
name: id.name,
|
|
ctxt: new_rename(from,to,id.ctxt)
|
|
}
|
|
}
|
|
|
|
|
|
// update the ctxts in a path to get a mark node
|
|
pub fn new_ident_marker(mark: uint) ->
|
|
@fn(ast::ident)->ast::ident {
|
|
|id : ast::ident|
|
|
ast::ident{
|
|
name: id.name,
|
|
ctxt: new_mark(mark,id.ctxt)
|
|
}
|
|
}
|
|
|
|
// perform resolution (in the MTWT sense) on all of the
|
|
// idents in the tree. This is the final step in expansion.
|
|
pub fn new_ident_resolver() ->
|
|
@fn(ast::ident)->ast::ident {
|
|
|id : ast::ident|
|
|
ast::ident {
|
|
name : resolve(id),
|
|
ctxt : illegal_ctxt
|
|
}
|
|
}
|
|
|
|
|
|
#[cfg(test)]
|
|
mod test {
|
|
use super::*;
|
|
use ast;
|
|
use ast::{attribute_, attr_outer, meta_word, empty_ctxt};
|
|
use codemap;
|
|
use codemap::spanned;
|
|
use parse;
|
|
use parse::token::{intern, get_ident_interner};
|
|
use print::pprust;
|
|
use util::parser_testing::{string_to_item, string_to_pat, strs_to_idents};
|
|
use visit::{mk_vt};
|
|
|
|
// make sure that fail! is present
|
|
#[test] fn fail_exists_test () {
|
|
let src = @"fn main() { fail!(\"something appropriately gloomy\");}";
|
|
let sess = parse::new_parse_sess(None);
|
|
let crate_ast = parse::parse_crate_from_source_str(
|
|
@"<test>",
|
|
src,
|
|
~[],sess);
|
|
let crate_ast = inject_std_macros(sess, ~[], crate_ast);
|
|
// don't bother with striping, doesn't affect fail!.
|
|
expand_crate(sess,~[],crate_ast);
|
|
}
|
|
|
|
// these following tests are quite fragile, in that they don't test what
|
|
// *kind* of failure occurs.
|
|
|
|
// make sure that macros can leave scope
|
|
#[should_fail]
|
|
#[test] fn macros_cant_escape_fns_test () {
|
|
let src = @"fn bogus() {macro_rules! z (() => (3+4))}\
|
|
fn inty() -> int { z!() }";
|
|
let sess = parse::new_parse_sess(None);
|
|
let crate_ast = parse::parse_crate_from_source_str(
|
|
@"<test>",
|
|
src,
|
|
~[],sess);
|
|
// should fail:
|
|
expand_crate(sess,~[],crate_ast);
|
|
}
|
|
|
|
// make sure that macros can leave scope for modules
|
|
#[should_fail]
|
|
#[test] fn macros_cant_escape_mods_test () {
|
|
let src = @"mod foo {macro_rules! z (() => (3+4))}\
|
|
fn inty() -> int { z!() }";
|
|
let sess = parse::new_parse_sess(None);
|
|
let crate_ast = parse::parse_crate_from_source_str(
|
|
@"<test>",
|
|
src,
|
|
~[],sess);
|
|
// should fail:
|
|
expand_crate(sess,~[],crate_ast);
|
|
}
|
|
|
|
// macro_escape modules shouldn't cause macros to leave scope
|
|
#[test] fn macros_can_escape_flattened_mods_test () {
|
|
let src = @"#[macro_escape] mod foo {macro_rules! z (() => (3+4))}\
|
|
fn inty() -> int { z!() }";
|
|
let sess = parse::new_parse_sess(None);
|
|
let crate_ast = parse::parse_crate_from_source_str(
|
|
@"<test>",
|
|
src,
|
|
~[], sess);
|
|
// should fail:
|
|
expand_crate(sess,~[],crate_ast);
|
|
}
|
|
|
|
#[test] fn std_macros_must_parse () {
|
|
let src = super::std_macros();
|
|
let sess = parse::new_parse_sess(None);
|
|
let cfg = ~[];
|
|
let item_ast = parse::parse_item_from_source_str(
|
|
@"<test>",
|
|
src,
|
|
cfg,~[],sess);
|
|
match item_ast {
|
|
Some(_) => (), // success
|
|
None => fail!("expected this to parse")
|
|
}
|
|
}
|
|
|
|
#[test] fn test_contains_flatten (){
|
|
let attr1 = make_dummy_attr (@"foo");
|
|
let attr2 = make_dummy_attr (@"bar");
|
|
let escape_attr = make_dummy_attr (@"macro_escape");
|
|
let attrs1 = ~[attr1, escape_attr, attr2];
|
|
assert_eq!(contains_macro_escape (attrs1),true);
|
|
let attrs2 = ~[attr1,attr2];
|
|
assert_eq!(contains_macro_escape (attrs2),false);
|
|
}
|
|
|
|
// make a "meta_word" outer attribute with the given name
|
|
fn make_dummy_attr(s: @str) -> ast::attribute {
|
|
spanned {
|
|
span:codemap::dummy_sp(),
|
|
node: attribute_ {
|
|
style: attr_outer,
|
|
value: @spanned {
|
|
node: meta_word(s),
|
|
span: codemap::dummy_sp(),
|
|
},
|
|
is_sugared_doc: false,
|
|
}
|
|
}
|
|
}
|
|
|
|
#[test]
|
|
fn renaming () {
|
|
let maybe_item_ast = string_to_item(@"fn a() -> int { let b = 13; b }");
|
|
let item_ast = match maybe_item_ast {
|
|
Some(x) => x,
|
|
None => fail!("test case fail")
|
|
};
|
|
let a_name = intern("a");
|
|
let a2_name = intern("a2");
|
|
let renamer = new_ident_renamer(ast::ident{name:a_name,ctxt:empty_ctxt},
|
|
a2_name);
|
|
let renamed_ast = fun_to_ident_folder(renamer).fold_item(item_ast).get();
|
|
let resolver = new_ident_resolver();
|
|
let resolved_ast = fun_to_ident_folder(resolver).fold_item(renamed_ast).get();
|
|
let resolved_as_str = pprust::item_to_str(resolved_ast,
|
|
get_ident_interner());
|
|
assert_eq!(resolved_as_str,~"fn a2() -> int { let b = 13; b }");
|
|
|
|
|
|
}
|
|
|
|
// sigh... it looks like I have two different renaming mechanisms, now...
|
|
|
|
#[test]
|
|
fn pat_idents(){
|
|
let pat = string_to_pat(@"(a,Foo{x:c @ (b,9),y:Bar(4,d)})");
|
|
let pat_idents = new_name_finder();
|
|
let idents = @mut ~[];
|
|
((*pat_idents).visit_pat)(pat, (idents, mk_vt(pat_idents)));
|
|
assert_eq!(idents,@mut strs_to_idents(~["a","c","b","d"]));
|
|
}
|
|
}
|