1 // Copyright 2012-2014 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 use ast::{Block, Crate, DeclLocal, ExprMac, PatMac};
12 use ast::{Local, Ident, MacInvocTT};
13 use ast::{ItemMac, MacStmtWithSemicolon, Mrk, Stmt, StmtDecl, StmtMac};
14 use ast::{StmtExpr, StmtSemi};
17 use ast_util::path_to_ident;
19 use ext::build::AstBuilder;
21 use attr::AttrMetaMethods;
23 use codemap::{Span, Spanned, ExpnInfo, NameAndSpan, MacroBang, MacroAttribute};
28 use parse::token::{fresh_mark, fresh_name, intern};
31 use util::small_vector::SmallVector;
35 pub fn expand_type(t: P<ast::Ty>,
36 fld: &mut MacroExpander,
37 impl_ty: Option<P<ast::Ty>>)
39 debug!("expanding type {} with impl_ty {}", t, impl_ty);
40 let t = match (t.node.clone(), impl_ty) {
41 // Expand uses of `Self` in impls to the concrete type.
42 (ast::Ty_::TyPath(ref path, _), Some(ref impl_ty)) => {
43 let path_as_ident = path_to_ident(path);
44 // Note unhygenic comparison here. I think this is correct, since
45 // even though `Self` is almost just a type parameter, the treatment
46 // for this expansion is as if it were a keyword.
47 if path_as_ident.is_some() &&
48 path_as_ident.unwrap().name == token::special_idents::type_self.name {
56 fold::noop_fold_ty(t, fld)
59 pub fn expand_expr(e: P<ast::Expr>, fld: &mut MacroExpander) -> P<ast::Expr> {
60 e.and_then(|ast::Expr {id, node, span}| match node {
61 // expr_mac should really be expr_ext or something; it's the
62 // entry-point for all syntax extensions.
63 ast::ExprMac(mac) => {
64 let expanded_expr = match expand_mac_invoc(mac, span,
69 return DummyResult::raw_expr(span);
73 // Keep going, outside-in.
75 let fully_expanded = fld.fold_expr(expanded_expr);
78 fully_expanded.map(|e| ast::Expr {
79 id: ast::DUMMY_NODE_ID,
85 ast::ExprWhile(cond, body, opt_ident) => {
86 let cond = fld.fold_expr(cond);
87 let (body, opt_ident) = expand_loop_block(body, opt_ident, fld);
88 fld.cx.expr(span, ast::ExprWhile(cond, body, opt_ident))
91 // Desugar ExprWhileLet
92 // From: `[opt_ident]: while let <pat> = <expr> <body>`
93 ast::ExprWhileLet(pat, expr, body, opt_ident) => {
96 // [opt_ident]: loop {
105 let body_expr = fld.cx.expr_block(body);
106 fld.cx.arm(pat.span, vec![pat], body_expr)
111 let pat_under = fld.cx.pat_wild(span);
112 let break_expr = fld.cx.expr_break(span);
113 fld.cx.arm(span, vec![pat_under], break_expr)
116 // `match <expr> { ... }`
117 let arms = vec![pat_arm, break_arm];
118 let match_expr = fld.cx.expr(span,
119 ast::ExprMatch(expr, arms, ast::MatchSource::WhileLetDesugar));
121 // `[opt_ident]: loop { ... }`
122 let loop_block = fld.cx.block_expr(match_expr);
123 let (loop_block, opt_ident) = expand_loop_block(loop_block, opt_ident, fld);
124 fld.cx.expr(span, ast::ExprLoop(loop_block, opt_ident))
128 // From: `if let <pat> = <expr> <body> [<elseopt>]`
129 ast::ExprIfLet(pat, expr, body, mut elseopt) => {
134 // [_ if <elseopt_if_cond> => <elseopt_if_body>,]
135 // _ => [<elseopt> | ()]
140 let body_expr = fld.cx.expr_block(body);
141 fld.cx.arm(pat.span, vec![pat], body_expr)
144 // `[_ if <elseopt_if_cond> => <elseopt_if_body>,]`
146 let mut arms = vec![];
148 let elseopt_continue = elseopt
149 .and_then(|els| els.and_then(|els| match els.node {
151 ast::ExprIf(cond, then, elseopt) => {
152 let pat_under = fld.cx.pat_wild(span);
155 pats: vec![pat_under],
157 body: fld.cx.expr_block(then)
159 elseopt.map(|elseopt| (elseopt, true))
161 _ => Some((P(els), false))
163 match elseopt_continue {
167 Some((e, false)) => {
180 let contains_else_clause = elseopt.is_some();
182 // `_ => [<elseopt> | ()]`
184 let pat_under = fld.cx.pat_wild(span);
185 let else_expr = elseopt.unwrap_or_else(|| fld.cx.expr_tuple(span, vec![]));
186 fld.cx.arm(span, vec![pat_under], else_expr)
189 let mut arms = Vec::with_capacity(else_if_arms.len() + 2);
191 arms.extend(else_if_arms.into_iter());
194 let match_expr = fld.cx.expr(span,
195 ast::ExprMatch(expr, arms,
196 ast::MatchSource::IfLetDesugar {
197 contains_else_clause: contains_else_clause,
199 fld.fold_expr(match_expr)
202 // Desugar support for ExprIfLet in the ExprIf else position
203 ast::ExprIf(cond, blk, elseopt) => {
204 let elseopt = elseopt.map(|els| els.and_then(|els| match els.node {
205 ast::ExprIfLet(..) => {
206 // wrap the if-let expr in a block
208 let blk = P(ast::Block {
212 id: ast::DUMMY_NODE_ID,
213 rules: ast::DefaultBlock,
216 fld.cx.expr_block(blk)
220 let if_expr = fld.cx.expr(span, ast::ExprIf(cond, blk, elseopt));
221 if_expr.map(|e| noop_fold_expr(e, fld))
224 ast::ExprLoop(loop_block, opt_ident) => {
225 let (loop_block, opt_ident) = expand_loop_block(loop_block, opt_ident, fld);
226 fld.cx.expr(span, ast::ExprLoop(loop_block, opt_ident))
229 ast::ExprForLoop(pat, head, body, opt_ident) => {
230 let pat = fld.fold_pat(pat);
231 let head = fld.fold_expr(head);
232 let (body, opt_ident) = expand_loop_block(body, opt_ident, fld);
233 fld.cx.expr(span, ast::ExprForLoop(pat, head, body, opt_ident))
236 ast::ExprClosure(capture_clause, opt_kind, fn_decl, block) => {
237 let (rewritten_fn_decl, rewritten_block)
238 = expand_and_rename_fn_decl_and_block(fn_decl, block, fld);
239 let new_node = ast::ExprClosure(capture_clause,
243 P(ast::Expr{id:id, node: new_node, span: fld.new_span(span)})
247 P(noop_fold_expr(ast::Expr {
256 /// Expand a (not-ident-style) macro invocation. Returns the result
257 /// of expansion and the mark which must be applied to the result.
258 /// Our current interface doesn't allow us to apply the mark to the
259 /// result until after calling make_expr, make_items, etc.
260 fn expand_mac_invoc<T, F, G>(mac: ast::Mac, span: codemap::Span,
263 fld: &mut MacroExpander)
265 F: FnOnce(Box<MacResult>) -> Option<T>,
266 G: FnOnce(T, Mrk) -> T,
269 // it would almost certainly be cleaner to pass the whole
270 // macro invocation in, rather than pulling it apart and
271 // marking the tts and the ctxt separately. This also goes
272 // for the other three macro invocation chunks of code
274 // Token-tree macros:
275 MacInvocTT(pth, tts, _) => {
276 if pth.segments.len() > 1u {
277 fld.cx.span_err(pth.span,
278 "expected macro name without module \
280 // let compilation continue
283 let extname = pth.segments[0].identifier;
284 let extnamestr = token::get_ident(extname);
285 match fld.cx.syntax_env.find(&extname.name) {
289 format!("macro undefined: '{}!'",
290 extnamestr.get())[]);
292 // let compilation continue
295 Some(rc) => match *rc {
296 NormalTT(ref expandfun, exp_span) => {
297 fld.cx.bt_push(ExpnInfo {
299 callee: NameAndSpan {
300 name: extnamestr.get().to_string(),
305 let fm = fresh_mark();
306 let marked_before = mark_tts(tts[], fm);
308 // The span that we pass to the expanders we want to
309 // be the root of the call stack. That's the most
310 // relevant span and it's the actual invocation of
312 let mac_span = fld.cx.original_span();
315 let expanded = expandfun.expand(fld.cx,
318 parse_thunk(expanded)
320 let parsed = match opt_parsed {
325 format!("non-expression macro in expression position: {}",
331 Some(mark_thunk(parsed,fm))
336 format!("'{}' is not a tt-style macro",
337 extnamestr.get())[]);
346 /// Rename loop label and expand its loop body
348 /// The renaming procedure for loop is different in the sense that the loop
349 /// body is in a block enclosed by loop head so the renaming of loop label
350 /// must be propagated to the enclosed context.
351 fn expand_loop_block(loop_block: P<Block>,
352 opt_ident: Option<Ident>,
353 fld: &mut MacroExpander) -> (P<Block>, Option<Ident>) {
356 let new_label = fresh_name(&label);
357 let rename = (label, new_label);
359 // The rename *must not* be added to the pending list of current
360 // syntax context otherwise an unrelated `break` or `continue` in
361 // the same context will pick that up in the deferred renaming pass
362 // and be renamed incorrectly.
363 let mut rename_list = vec!(rename);
364 let mut rename_fld = IdentRenamer{renames: &mut rename_list};
365 let renamed_ident = rename_fld.fold_ident(label);
367 // The rename *must* be added to the enclosed syntax context for
368 // `break` or `continue` to pick up because by definition they are
369 // in a block enclosed by loop head.
370 fld.cx.syntax_env.push_frame();
371 fld.cx.syntax_env.info().pending_renames.push(rename);
372 let expanded_block = expand_block_elts(loop_block, fld);
373 fld.cx.syntax_env.pop_frame();
375 (expanded_block, Some(renamed_ident))
377 None => (fld.fold_block(loop_block), opt_ident)
381 // eval $e with a new exts frame.
382 // must be a macro so that $e isn't evaluated too early.
383 macro_rules! with_exts_frame {
384 ($extsboxexpr:expr,$macros_escape:expr,$e:expr) =>
385 ({$extsboxexpr.push_frame();
386 $extsboxexpr.info().macros_escape = $macros_escape;
388 $extsboxexpr.pop_frame();
393 // When we enter a module, record it, for the sake of `module!`
394 pub fn expand_item(it: P<ast::Item>, fld: &mut MacroExpander)
395 -> SmallVector<P<ast::Item>> {
396 let it = expand_item_modifiers(it, fld);
398 let mut decorator_items = SmallVector::zero();
399 let mut new_attrs = Vec::new();
400 for attr in it.attrs.iter() {
401 let mname = attr.name();
403 match fld.cx.syntax_env.find(&intern(mname.get())) {
404 Some(rc) => match *rc {
405 Decorator(ref dec) => {
406 attr::mark_used(attr);
408 fld.cx.bt_push(ExpnInfo {
409 call_site: attr.span,
410 callee: NameAndSpan {
411 name: mname.get().to_string(),
412 format: MacroAttribute,
417 // we'd ideally decorator_items.push_all(expand_item(item, fld)),
418 // but that double-mut-borrows fld
419 let mut items: SmallVector<P<ast::Item>> = SmallVector::zero();
420 dec.expand(fld.cx, attr.span, &*attr.node.value, &*it,
421 box |&mut : item| items.push(item));
422 decorator_items.extend(items.into_iter()
423 .flat_map(|item| expand_item(item, fld).into_iter()));
427 _ => new_attrs.push((*attr).clone()),
429 _ => new_attrs.push((*attr).clone()),
433 let mut new_items = match it.node {
434 ast::ItemMac(..) => expand_item_mac(it, fld),
435 ast::ItemMod(_) | ast::ItemForeignMod(_) => {
437 it.ident.name != parse::token::special_idents::invalid.name;
440 fld.cx.mod_push(it.ident);
442 let macro_use = contains_macro_use(fld, new_attrs[]);
443 let result = with_exts_frame!(fld.cx.syntax_env,
445 noop_fold_item(it, fld));
452 let it = P(ast::Item {
456 noop_fold_item(it, fld)
460 new_items.push_all(decorator_items);
464 fn expand_item_modifiers(mut it: P<ast::Item>, fld: &mut MacroExpander)
466 // partition the attributes into ItemModifiers and others
467 let (modifiers, other_attrs): (Vec<_>, _) = it.attrs.iter().cloned().partition(|attr| {
468 match fld.cx.syntax_env.find(&intern(attr.name().get())) {
469 Some(rc) => match *rc { Modifier(_) => true, _ => false },
473 // update the attrs, leave everything else alone. Is this mutation really a good idea?
479 if modifiers.is_empty() {
483 for attr in modifiers.iter() {
484 let mname = attr.name();
486 match fld.cx.syntax_env.find(&intern(mname.get())) {
487 Some(rc) => match *rc {
488 Modifier(ref mac) => {
489 attr::mark_used(attr);
490 fld.cx.bt_push(ExpnInfo {
491 call_site: attr.span,
492 callee: NameAndSpan {
493 name: mname.get().to_string(),
494 format: MacroAttribute,
498 it = mac.expand(fld.cx, attr.span, &*attr.node.value, it);
507 // expansion may have added new ItemModifiers
508 expand_item_modifiers(it, fld)
511 /// Expand item_underscore
512 fn expand_item_underscore(item: ast::Item_, fld: &mut MacroExpander) -> ast::Item_ {
514 ast::ItemFn(decl, fn_style, abi, generics, body) => {
515 let (rewritten_fn_decl, rewritten_body)
516 = expand_and_rename_fn_decl_and_block(decl, body, fld);
517 let expanded_generics = fold::noop_fold_generics(generics,fld);
518 ast::ItemFn(rewritten_fn_decl, fn_style, abi, expanded_generics, rewritten_body)
520 _ => noop_fold_item_underscore(item, fld)
524 // does this attribute list contain "macro_use" ?
525 fn contains_macro_use(fld: &mut MacroExpander, attrs: &[ast::Attribute]) -> bool {
526 for attr in attrs.iter() {
527 let mut is_use = attr.check_name("macro_use");
528 if attr.check_name("macro_escape") {
529 fld.cx.span_warn(attr.span, "macro_escape is a deprecated synonym for macro_use");
531 if let ast::AttrInner = attr.node.style {
532 fld.cx.span_help(attr.span, "consider an outer attribute, \
533 #[macro_use] mod ...");
538 match attr.node.value.node {
539 ast::MetaWord(..) => (),
540 _ => fld.cx.span_err(attr.span, "arguments to macro_use are not allowed here"),
548 // Support for item-position macro invocations, exactly the same
549 // logic as for expression-position macro invocations.
550 pub fn expand_item_mac(it: P<ast::Item>,
551 fld: &mut MacroExpander) -> SmallVector<P<ast::Item>> {
552 let (extname, path_span, tts) = match it.node {
553 ItemMac(codemap::Spanned {
554 node: MacInvocTT(ref pth, ref tts, _),
557 (pth.segments[0].identifier, pth.span, (*tts).clone())
559 _ => fld.cx.span_bug(it.span, "invalid item macro invocation")
562 let extnamestr = token::get_ident(extname);
563 let fm = fresh_mark();
565 let expanded = match fld.cx.syntax_env.find(&extname.name) {
567 fld.cx.span_err(path_span,
568 format!("macro undefined: '{}!'",
570 // let compilation continue
571 return SmallVector::zero();
574 Some(rc) => match *rc {
575 NormalTT(ref expander, span) => {
576 if it.ident.name != parse::token::special_idents::invalid.name {
579 format!("macro {}! expects no ident argument, \
582 token::get_ident(it.ident))[]);
583 return SmallVector::zero();
585 fld.cx.bt_push(ExpnInfo {
587 callee: NameAndSpan {
588 name: extnamestr.get().to_string(),
593 // mark before expansion:
594 let marked_before = mark_tts(tts[], fm);
595 expander.expand(fld.cx, it.span, marked_before[])
597 IdentTT(ref expander, span) => {
598 if it.ident.name == parse::token::special_idents::invalid.name {
599 fld.cx.span_err(path_span,
600 format!("macro {}! expects an ident argument",
601 extnamestr.get())[]);
602 return SmallVector::zero();
604 fld.cx.bt_push(ExpnInfo {
606 callee: NameAndSpan {
607 name: extnamestr.get().to_string(),
612 // mark before expansion:
613 let marked_tts = mark_tts(tts[], fm);
614 expander.expand(fld.cx, it.span, it.ident, marked_tts)
617 if it.ident.name == parse::token::special_idents::invalid.name {
618 fld.cx.span_err(path_span,
619 format!("macro_rules! expects an ident argument")[]);
620 return SmallVector::zero();
622 fld.cx.bt_push(ExpnInfo {
624 callee: NameAndSpan {
625 name: extnamestr.get().to_string(),
630 // DON'T mark before expansion.
632 let def = ast::MacroDef {
634 attrs: it.attrs.clone(),
635 id: ast::DUMMY_NODE_ID,
638 export: attr::contains_name(it.attrs.as_slice(), "macro_export"),
642 fld.cx.insert_macro(def);
644 // macro_rules! has a side effect but expands to nothing.
646 return SmallVector::zero();
649 fld.cx.span_err(it.span,
650 format!("{}! is not legal in item position",
651 extnamestr.get())[]);
652 return SmallVector::zero();
657 expanded.make_items()
660 let items = match items {
663 .map(|i| mark_item(i, fm))
664 .flat_map(|i| fld.fold_item(i).into_iter())
668 fld.cx.span_err(path_span,
669 format!("non-item macro in item position: {}",
670 extnamestr.get())[]);
671 return SmallVector::zero();
680 fn expand_stmt(s: Stmt, fld: &mut MacroExpander) -> SmallVector<P<Stmt>> {
681 let (mac, style) = match s.node {
682 StmtMac(mac, style) => (mac, style),
683 _ => return expand_non_macro_stmt(s, fld)
685 let expanded_stmt = match expand_mac_invoc(mac.and_then(|m| m), s.span,
690 return SmallVector::zero();
694 // Keep going, outside-in.
695 let fully_expanded = fld.fold_stmt(expanded_stmt);
698 if style == MacStmtWithSemicolon {
699 fully_expanded.into_iter().map(|s| s.map(|Spanned {node, span}| {
702 StmtExpr(e, stmt_id) => StmtSemi(e, stmt_id),
703 _ => node /* might already have a semi */
713 // expand a non-macro stmt. this is essentially the fallthrough for
714 // expand_stmt, above.
715 fn expand_non_macro_stmt(Spanned {node, span: stmt_span}: Stmt, fld: &mut MacroExpander)
716 -> SmallVector<P<Stmt>> {
719 StmtDecl(decl, node_id) => decl.and_then(|Spanned {node: decl, span}| match decl {
720 DeclLocal(local) => {
722 let rewritten_local = local.map(|Local {id, pat, ty, init, source, span}| {
723 // expand the ty since TyFixedLengthVec contains an Expr
724 // and thus may have a macro use
725 let expanded_ty = ty.map(|t| fld.fold_ty(t));
726 // expand the pat (it might contain macro uses):
727 let expanded_pat = fld.fold_pat(pat);
728 // find the PatIdents in the pattern:
729 // oh dear heaven... this is going to include the enum
730 // names, as well... but that should be okay, as long as
731 // the new names are gensyms for the old ones.
732 // generate fresh names, push them to a new pending list
733 let idents = pattern_bindings(&*expanded_pat);
734 let mut new_pending_renames =
735 idents.iter().map(|ident| (*ident, fresh_name(ident))).collect();
736 // rewrite the pattern using the new names (the old
737 // ones have already been applied):
738 let rewritten_pat = {
739 // nested binding to allow borrow to expire:
740 let mut rename_fld = IdentRenamer{renames: &mut new_pending_renames};
741 rename_fld.fold_pat(expanded_pat)
743 // add them to the existing pending renames:
744 fld.cx.syntax_env.info().pending_renames
745 .extend(new_pending_renames.into_iter());
750 // also, don't forget to expand the init:
751 init: init.map(|e| fld.fold_expr(e)),
756 SmallVector::one(P(Spanned {
757 node: StmtDecl(P(Spanned {
758 node: DeclLocal(rewritten_local),
766 noop_fold_stmt(Spanned {
767 node: StmtDecl(P(Spanned {
777 noop_fold_stmt(Spanned {
785 // expand the arm of a 'match', renaming for macro hygiene
786 fn expand_arm(arm: ast::Arm, fld: &mut MacroExpander) -> ast::Arm {
787 // expand pats... they might contain macro uses:
788 let expanded_pats = arm.pats.move_map(|pat| fld.fold_pat(pat));
789 if expanded_pats.len() == 0 {
790 panic!("encountered match arm with 0 patterns");
792 // all of the pats must have the same set of bindings, so use the
793 // first one to extract them and generate new names:
794 let idents = pattern_bindings(&*expanded_pats[0]);
795 let new_renames = idents.into_iter().map(|id| (id, fresh_name(&id))).collect();
796 // apply the renaming, but only to the PatIdents:
797 let mut rename_pats_fld = PatIdentRenamer{renames:&new_renames};
798 let rewritten_pats = expanded_pats.move_map(|pat| rename_pats_fld.fold_pat(pat));
799 // apply renaming and then expansion to the guard and the body:
800 let mut rename_fld = IdentRenamer{renames:&new_renames};
801 let rewritten_guard =
802 arm.guard.map(|g| fld.fold_expr(rename_fld.fold_expr(g)));
803 let rewritten_body = fld.fold_expr(rename_fld.fold_expr(arm.body));
805 attrs: arm.attrs.move_map(|x| fld.fold_attribute(x)),
806 pats: rewritten_pats,
807 guard: rewritten_guard,
808 body: rewritten_body,
812 /// A visitor that extracts the PatIdent (binding) paths
813 /// from a given thingy and puts them in a mutable
816 struct PatIdentFinder {
817 ident_accumulator: Vec<ast::Ident>
820 impl<'v> Visitor<'v> for PatIdentFinder {
821 fn visit_pat(&mut self, pattern: &ast::Pat) {
823 ast::Pat { id: _, node: ast::PatIdent(_, ref path1, ref inner), span: _ } => {
824 self.ident_accumulator.push(path1.node);
825 // visit optional subpattern of PatIdent:
826 for subpat in inner.iter() {
827 self.visit_pat(&**subpat)
830 // use the default traversal for non-PatIdents
831 _ => visit::walk_pat(self, pattern)
836 /// find the PatIdent paths in a pattern
837 fn pattern_bindings(pat: &ast::Pat) -> Vec<ast::Ident> {
838 let mut name_finder = PatIdentFinder{ident_accumulator:Vec::new()};
839 name_finder.visit_pat(pat);
840 name_finder.ident_accumulator
843 /// find the PatIdent paths in a
844 fn fn_decl_arg_bindings(fn_decl: &ast::FnDecl) -> Vec<ast::Ident> {
845 let mut pat_idents = PatIdentFinder{ident_accumulator:Vec::new()};
846 for arg in fn_decl.inputs.iter() {
847 pat_idents.visit_pat(&*arg.pat);
849 pat_idents.ident_accumulator
852 // expand a block. pushes a new exts_frame, then calls expand_block_elts
853 pub fn expand_block(blk: P<Block>, fld: &mut MacroExpander) -> P<Block> {
854 // see note below about treatment of exts table
855 with_exts_frame!(fld.cx.syntax_env,false,
856 expand_block_elts(blk, fld))
859 // expand the elements of a block.
860 pub fn expand_block_elts(b: P<Block>, fld: &mut MacroExpander) -> P<Block> {
861 b.map(|Block {id, view_items, stmts, expr, rules, span}| {
862 let new_view_items = view_items.into_iter().map(|x| fld.fold_view_item(x)).collect();
863 let new_stmts = stmts.into_iter().flat_map(|x| {
864 // perform all pending renames
866 let pending_renames = &mut fld.cx.syntax_env.info().pending_renames;
867 let mut rename_fld = IdentRenamer{renames:pending_renames};
868 rename_fld.fold_stmt(x).expect_one("rename_fold didn't return one value")
870 // expand macros in the statement
871 fld.fold_stmt(renamed_stmt).into_iter()
873 let new_expr = expr.map(|x| {
875 let pending_renames = &mut fld.cx.syntax_env.info().pending_renames;
876 let mut rename_fld = IdentRenamer{renames:pending_renames};
877 rename_fld.fold_expr(x)
883 view_items: new_view_items,
892 fn expand_pat(p: P<ast::Pat>, fld: &mut MacroExpander) -> P<ast::Pat> {
895 _ => return noop_fold_pat(p, fld)
897 p.map(|ast::Pat {node, span, ..}| {
898 let (pth, tts) = match node {
899 PatMac(mac) => match mac.node {
900 MacInvocTT(pth, tts, _) => {
906 if pth.segments.len() > 1u {
907 fld.cx.span_err(pth.span, "expected macro name without module separators");
908 return DummyResult::raw_pat(span);
910 let extname = pth.segments[0].identifier;
911 let extnamestr = token::get_ident(extname);
912 let marked_after = match fld.cx.syntax_env.find(&extname.name) {
914 fld.cx.span_err(pth.span,
915 format!("macro undefined: '{}!'",
917 // let compilation continue
918 return DummyResult::raw_pat(span);
921 Some(rc) => match *rc {
922 NormalTT(ref expander, tt_span) => {
923 fld.cx.bt_push(ExpnInfo {
925 callee: NameAndSpan {
926 name: extnamestr.get().to_string(),
932 let fm = fresh_mark();
933 let marked_before = mark_tts(tts[], fm);
934 let mac_span = fld.cx.original_span();
935 let expanded = match expander.expand(fld.cx,
937 marked_before[]).make_pat() {
943 "non-pattern macro in pattern position: {}",
947 return DummyResult::raw_pat(span);
952 mark_pat(expanded,fm)
955 fld.cx.span_err(span,
956 format!("{}! is not legal in pattern position",
957 extnamestr.get())[]);
958 return DummyResult::raw_pat(span);
964 fld.fold_pat(marked_after).node.clone();
968 id: ast::DUMMY_NODE_ID,
969 node: fully_expanded,
975 /// A tree-folder that applies every rename in its (mutable) list
976 /// to every identifier, including both bindings and varrefs
977 /// (and lots of things that will turn out to be neither)
978 pub struct IdentRenamer<'a> {
979 renames: &'a mtwt::RenameList,
982 impl<'a> Folder for IdentRenamer<'a> {
983 fn fold_ident(&mut self, id: Ident) -> Ident {
986 ctxt: mtwt::apply_renames(self.renames, id.ctxt),
989 fn fold_mac(&mut self, mac: ast::Mac) -> ast::Mac {
990 fold::noop_fold_mac(mac, self)
994 /// A tree-folder that applies every rename in its list to
995 /// the idents that are in PatIdent patterns. This is more narrowly
996 /// focused than IdentRenamer, and is needed for FnDecl,
997 /// where we want to rename the args but not the fn name or the generics etc.
998 pub struct PatIdentRenamer<'a> {
999 renames: &'a mtwt::RenameList,
1002 impl<'a> Folder for PatIdentRenamer<'a> {
1003 fn fold_pat(&mut self, pat: P<ast::Pat>) -> P<ast::Pat> {
1005 ast::PatIdent(..) => {},
1006 _ => return noop_fold_pat(pat, self)
1009 pat.map(|ast::Pat {id, node, span}| match node {
1010 ast::PatIdent(binding_mode, Spanned{span: sp, node: ident}, sub) => {
1011 let new_ident = Ident{name: ident.name,
1012 ctxt: mtwt::apply_renames(self.renames, ident.ctxt)};
1014 ast::PatIdent(binding_mode,
1015 Spanned{span: self.new_span(sp), node: new_ident},
1016 sub.map(|p| self.fold_pat(p)));
1020 span: self.new_span(span)
1026 fn fold_mac(&mut self, mac: ast::Mac) -> ast::Mac {
1027 fold::noop_fold_mac(mac, self)
1032 fn expand_method(m: P<ast::Method>, fld: &mut MacroExpander) -> SmallVector<P<ast::Method>> {
1033 m.and_then(|m| match m.node {
1034 ast::MethDecl(ident,
1042 let id = fld.new_id(m.id);
1043 let (rewritten_fn_decl, rewritten_body)
1044 = expand_and_rename_fn_decl_and_block(decl,body,fld);
1045 SmallVector::one(P(ast::Method {
1046 attrs: m.attrs.move_map(|a| fld.fold_attribute(a)),
1048 span: fld.new_span(m.span),
1049 node: ast::MethDecl(fld.fold_ident(ident),
1050 noop_fold_generics(generics, fld),
1052 fld.fold_explicit_self(explicit_self),
1059 ast::MethMac(mac) => {
1060 let maybe_new_methods =
1061 expand_mac_invoc(mac, m.span,
1062 |r| r.make_methods(),
1063 |meths, mark| meths.move_map(|m| mark_method(m, mark)),
1066 match maybe_new_methods {
1068 // expand again if necessary
1069 let new_methods = methods.into_iter()
1070 .flat_map(|m| fld.fold_method(m).into_iter())
1075 None => SmallVector::zero()
1081 /// Given a fn_decl and a block and a MacroExpander, expand the fn_decl, then use the
1082 /// PatIdents in its arguments to perform renaming in the FnDecl and
1083 /// the block, returning both the new FnDecl and the new Block.
1084 fn expand_and_rename_fn_decl_and_block(fn_decl: P<ast::FnDecl>, block: P<ast::Block>,
1085 fld: &mut MacroExpander)
1086 -> (P<ast::FnDecl>, P<ast::Block>) {
1087 let expanded_decl = fld.fold_fn_decl(fn_decl);
1088 let idents = fn_decl_arg_bindings(&*expanded_decl);
1090 idents.iter().map(|id : &ast::Ident| (*id,fresh_name(id))).collect();
1091 // first, a renamer for the PatIdents, for the fn_decl:
1092 let mut rename_pat_fld = PatIdentRenamer{renames: &renames};
1093 let rewritten_fn_decl = rename_pat_fld.fold_fn_decl(expanded_decl);
1094 // now, a renamer for *all* idents, for the body:
1095 let mut rename_fld = IdentRenamer{renames: &renames};
1096 let rewritten_body = fld.fold_block(rename_fld.fold_block(block));
1097 (rewritten_fn_decl,rewritten_body)
1100 /// A tree-folder that performs macro expansion
1101 pub struct MacroExpander<'a, 'b:'a> {
1102 pub cx: &'a mut ExtCtxt<'b>,
1103 // The type of the impl currently being expanded.
1104 current_impl_type: Option<P<ast::Ty>>,
1107 impl<'a, 'b> MacroExpander<'a, 'b> {
1108 pub fn new(cx: &'a mut ExtCtxt<'b>) -> MacroExpander<'a, 'b> {
1109 MacroExpander { cx: cx, current_impl_type: None }
1113 impl<'a, 'b> Folder for MacroExpander<'a, 'b> {
1114 fn fold_expr(&mut self, expr: P<ast::Expr>) -> P<ast::Expr> {
1115 expand_expr(expr, self)
1118 fn fold_pat(&mut self, pat: P<ast::Pat>) -> P<ast::Pat> {
1119 expand_pat(pat, self)
1122 fn fold_item(&mut self, item: P<ast::Item>) -> SmallVector<P<ast::Item>> {
1123 let prev_type = self.current_impl_type.clone();
1124 if let ast::Item_::ItemImpl(_, _, _, _, ref ty, _) = item.node {
1125 self.current_impl_type = Some(ty.clone());
1128 let result = expand_item(item, self);
1129 self.current_impl_type = prev_type;
1133 fn fold_item_underscore(&mut self, item: ast::Item_) -> ast::Item_ {
1134 expand_item_underscore(item, self)
1137 fn fold_stmt(&mut self, stmt: P<ast::Stmt>) -> SmallVector<P<ast::Stmt>> {
1138 stmt.and_then(|stmt| expand_stmt(stmt, self))
1141 fn fold_block(&mut self, block: P<Block>) -> P<Block> {
1142 expand_block(block, self)
1145 fn fold_arm(&mut self, arm: ast::Arm) -> ast::Arm {
1146 expand_arm(arm, self)
1149 fn fold_method(&mut self, method: P<ast::Method>) -> SmallVector<P<ast::Method>> {
1150 expand_method(method, self)
1153 fn fold_ty(&mut self, t: P<ast::Ty>) -> P<ast::Ty> {
1154 let impl_type = self.current_impl_type.clone();
1155 expand_type(t, self, impl_type)
1158 fn new_span(&mut self, span: Span) -> Span {
1159 new_span(self.cx, span)
1163 fn new_span(cx: &ExtCtxt, sp: Span) -> Span {
1164 /* this discards information in the case of macro-defining macros */
1168 expn_id: cx.backtrace(),
1172 pub struct ExpansionConfig {
1173 pub crate_name: String,
1174 pub enable_quotes: bool,
1175 pub recursion_limit: uint,
1178 impl ExpansionConfig {
1179 pub fn default(crate_name: String) -> ExpansionConfig {
1181 crate_name: crate_name,
1182 enable_quotes: false,
1183 recursion_limit: 64,
1188 pub fn expand_crate(parse_sess: &parse::ParseSess,
1189 cfg: ExpansionConfig,
1190 // these are the macros being imported to this crate:
1191 imported_macros: Vec<ast::MacroDef>,
1192 user_exts: Vec<NamedSyntaxExtension>,
1193 c: Crate) -> Crate {
1194 let mut cx = ExtCtxt::new(parse_sess, c.config.clone(), cfg);
1195 let mut expander = MacroExpander::new(&mut cx);
1197 for def in imported_macros.into_iter() {
1198 expander.cx.insert_macro(def);
1201 for (name, extension) in user_exts.into_iter() {
1202 expander.cx.syntax_env.insert(name, extension);
1205 let mut ret = expander.fold_crate(c);
1206 ret.exported_macros = expander.cx.exported_macros.clone();
1207 parse_sess.span_diagnostic.handler().abort_if_errors();
1211 // HYGIENIC CONTEXT EXTENSION:
1212 // all of these functions are for walking over
1213 // ASTs and making some change to the context of every
1214 // element that has one. a CtxtFn is a trait-ified
1215 // version of a closure in (SyntaxContext -> SyntaxContext).
1216 // the ones defined here include:
1217 // Marker - add a mark to a context
1219 // A Marker adds the given mark to the syntax context
1220 struct Marker { mark: Mrk }
1222 impl Folder for Marker {
1223 fn fold_ident(&mut self, id: Ident) -> Ident {
1226 ctxt: mtwt::apply_mark(self.mark, id.ctxt)
1229 fn fold_mac(&mut self, Spanned {node, span}: ast::Mac) -> ast::Mac {
1232 MacInvocTT(path, tts, ctxt) => {
1233 MacInvocTT(self.fold_path(path),
1234 self.fold_tts(tts[]),
1235 mtwt::apply_mark(self.mark, ctxt))
1243 // apply a given mark to the given token trees. Used prior to expansion of a macro.
1244 fn mark_tts(tts: &[TokenTree], m: Mrk) -> Vec<TokenTree> {
1245 noop_fold_tts(tts, &mut Marker{mark:m})
1248 // apply a given mark to the given expr. Used following the expansion of a macro.
1249 fn mark_expr(expr: P<ast::Expr>, m: Mrk) -> P<ast::Expr> {
1250 Marker{mark:m}.fold_expr(expr)
1253 // apply a given mark to the given pattern. Used following the expansion of a macro.
1254 fn mark_pat(pat: P<ast::Pat>, m: Mrk) -> P<ast::Pat> {
1255 Marker{mark:m}.fold_pat(pat)
1258 // apply a given mark to the given stmt. Used following the expansion of a macro.
1259 fn mark_stmt(expr: P<ast::Stmt>, m: Mrk) -> P<ast::Stmt> {
1260 Marker{mark:m}.fold_stmt(expr)
1261 .expect_one("marking a stmt didn't return exactly one stmt")
1264 // apply a given mark to the given item. Used following the expansion of a macro.
1265 fn mark_item(expr: P<ast::Item>, m: Mrk) -> P<ast::Item> {
1266 Marker{mark:m}.fold_item(expr)
1267 .expect_one("marking an item didn't return exactly one item")
1270 // apply a given mark to the given item. Used following the expansion of a macro.
1271 fn mark_method(expr: P<ast::Method>, m: Mrk) -> P<ast::Method> {
1272 Marker{mark:m}.fold_method(expr)
1273 .expect_one("marking an item didn't return exactly one method")
1276 /// Check that there are no macro invocations left in the AST:
1277 pub fn check_for_macros(sess: &parse::ParseSess, krate: &ast::Crate) {
1278 visit::walk_crate(&mut MacroExterminator{sess:sess}, krate);
1281 /// A visitor that ensures that no macro invocations remain in an AST.
1282 struct MacroExterminator<'a>{
1283 sess: &'a parse::ParseSess
1286 impl<'a, 'v> Visitor<'v> for MacroExterminator<'a> {
1287 fn visit_mac(&mut self, mac: &ast::Mac) {
1288 self.sess.span_diagnostic.span_bug(mac.span,
1289 "macro exterminator: expected AST \
1290 with no macro invocations");
1297 use super::{pattern_bindings, expand_crate, contains_macro_use};
1298 use super::{PatIdentFinder, IdentRenamer, PatIdentRenamer, ExpansionConfig};
1300 use ast::{Attribute_, AttrOuter, MetaWord, Name};
1303 use codemap::Spanned;
1309 use util::parser_testing::{string_to_parser};
1310 use util::parser_testing::{string_to_pat, string_to_crate, strs_to_idents};
1314 // a visitor that extracts the paths
1315 // from a given thingy and puts them in a mutable
1316 // array (passed in to the traversal)
1318 struct PathExprFinderContext {
1319 path_accumulator: Vec<ast::Path> ,
1322 impl<'v> Visitor<'v> for PathExprFinderContext {
1323 fn visit_expr(&mut self, expr: &ast::Expr) {
1325 ast::ExprPath(ref p) => {
1326 self.path_accumulator.push(p.clone());
1327 // not calling visit_path, but it should be fine.
1329 _ => visit::walk_expr(self, expr)
1334 // find the variable references in a crate
1335 fn crate_varrefs(the_crate : &ast::Crate) -> Vec<ast::Path> {
1336 let mut path_finder = PathExprFinderContext{path_accumulator:Vec::new()};
1337 visit::walk_crate(&mut path_finder, the_crate);
1338 path_finder.path_accumulator
1341 /// A Visitor that extracts the identifiers from a thingy.
1342 // as a side note, I'm starting to want to abstract over these....
1343 struct IdentFinder {
1344 ident_accumulator: Vec<ast::Ident>
1347 impl<'v> Visitor<'v> for IdentFinder {
1348 fn visit_ident(&mut self, _: codemap::Span, id: ast::Ident){
1349 self.ident_accumulator.push(id);
1353 /// Find the idents in a crate
1354 fn crate_idents(the_crate: &ast::Crate) -> Vec<ast::Ident> {
1355 let mut ident_finder = IdentFinder{ident_accumulator: Vec::new()};
1356 visit::walk_crate(&mut ident_finder, the_crate);
1357 ident_finder.ident_accumulator
1360 // these following tests are quite fragile, in that they don't test what
1361 // *kind* of failure occurs.
1363 fn test_ecfg() -> ExpansionConfig {
1364 ExpansionConfig::default("test".to_string())
1367 // make sure that macros can't escape fns
1369 #[test] fn macros_cant_escape_fns_test () {
1370 let src = "fn bogus() {macro_rules! z (() => (3+4));}\
1371 fn inty() -> int { z!() }".to_string();
1372 let sess = parse::new_parse_sess();
1373 let crate_ast = parse::parse_crate_from_source_str(
1374 "<test>".to_string(),
1378 expand_crate(&sess,test_ecfg(),vec!(),vec!(),crate_ast);
1381 // make sure that macros can't escape modules
1383 #[test] fn macros_cant_escape_mods_test () {
1384 let src = "mod foo {macro_rules! z (() => (3+4));}\
1385 fn inty() -> int { z!() }".to_string();
1386 let sess = parse::new_parse_sess();
1387 let crate_ast = parse::parse_crate_from_source_str(
1388 "<test>".to_string(),
1391 expand_crate(&sess,test_ecfg(),vec!(),vec!(),crate_ast);
1394 // macro_use modules should allow macros to escape
1395 #[test] fn macros_can_escape_flattened_mods_test () {
1396 let src = "#[macro_use] mod foo {macro_rules! z (() => (3+4));}\
1397 fn inty() -> int { z!() }".to_string();
1398 let sess = parse::new_parse_sess();
1399 let crate_ast = parse::parse_crate_from_source_str(
1400 "<test>".to_string(),
1403 expand_crate(&sess, test_ecfg(), vec!(), vec!(), crate_ast);
1406 // make a MetaWord outer attribute with the given name
1407 fn make_dummy_attr(s: &str) -> ast::Attribute {
1409 span:codemap::DUMMY_SP,
1411 id: attr::mk_attr_id(),
1414 node: MetaWord(token::intern_and_get_ident(s)),
1415 span: codemap::DUMMY_SP,
1417 is_sugared_doc: false,
1422 fn expand_crate_str(crate_str: String) -> ast::Crate {
1423 let ps = parse::new_parse_sess();
1424 let crate_ast = string_to_parser(&ps, crate_str).parse_crate_mod();
1425 // the cfg argument actually does matter, here...
1426 expand_crate(&ps,test_ecfg(),vec!(),vec!(),crate_ast)
1429 // find the pat_ident paths in a crate
1430 fn crate_bindings(the_crate : &ast::Crate) -> Vec<ast::Ident> {
1431 let mut name_finder = PatIdentFinder{ident_accumulator:Vec::new()};
1432 visit::walk_crate(&mut name_finder, the_crate);
1433 name_finder.ident_accumulator
1436 #[test] fn macro_tokens_should_match(){
1438 "macro_rules! m((a)=>(13)) ;fn main(){m!(a);}".to_string());
1441 // should be able to use a bound identifier as a literal in a macro definition:
1442 #[test] fn self_macro_parsing(){
1444 "macro_rules! foo ((zz) => (287u;));
1445 fn f(zz : int) {foo!(zz);}".to_string()
1449 // renaming tests expand a crate and then check that the bindings match
1450 // the right varrefs. The specification of the test case includes the
1451 // text of the crate, and also an array of arrays. Each element in the
1452 // outer array corresponds to a binding in the traversal of the AST
1453 // induced by visit. Each of these arrays contains a list of indexes,
1454 // interpreted as the varrefs in the varref traversal that this binding
1455 // should match. So, for instance, in a program with two bindings and
1456 // three varrefs, the array ~[~[1,2],~[0]] would indicate that the first
1457 // binding should match the second two varrefs, and the second binding
1458 // should match the first varref.
1460 // Put differently; this is a sparse representation of a boolean matrix
1461 // indicating which bindings capture which identifiers.
1463 // Note also that this matrix is dependent on the implicit ordering of
1464 // the bindings and the varrefs discovered by the name-finder and the path-finder.
1466 // The comparisons are done post-mtwt-resolve, so we're comparing renamed
1467 // names; differences in marks don't matter any more.
1469 // oog... I also want tests that check "bound-identifier-=?". That is,
1470 // not just "do these have the same name", but "do they have the same
1471 // name *and* the same marks"? Understanding this is really pretty painful.
1472 // in principle, you might want to control this boolean on a per-varref basis,
1473 // but that would make things even harder to understand, and might not be
1474 // necessary for thorough testing.
1475 type RenamingTest = (&'static str, Vec<Vec<uint>>, bool);
1478 fn automatic_renaming () {
1479 let tests: Vec<RenamingTest> =
1480 vec!(// b & c should get new names throughout, in the expr too:
1481 ("fn a() -> int { let b = 13; let c = b; b+c }",
1482 vec!(vec!(0,1),vec!(2)), false),
1483 // both x's should be renamed (how is this causing a bug?)
1484 ("fn main () {let x: int = 13;x;}",
1485 vec!(vec!(0)), false),
1486 // the use of b after the + should be renamed, the other one not:
1487 ("macro_rules! f (($x:ident) => (b + $x)); fn a() -> int { let b = 13; f!(b)}",
1488 vec!(vec!(1)), false),
1489 // the b before the plus should not be renamed (requires marks)
1490 ("macro_rules! f (($x:ident) => ({let b=9; ($x + b)})); fn a() -> int { f!(b)}",
1491 vec!(vec!(1)), false),
1492 // the marks going in and out of letty should cancel, allowing that $x to
1493 // capture the one following the semicolon.
1494 // this was an awesome test case, and caught a *lot* of bugs.
1495 ("macro_rules! letty(($x:ident) => (let $x = 15;));
1496 macro_rules! user(($x:ident) => ({letty!($x); $x}));
1497 fn main() -> int {user!(z)}",
1498 vec!(vec!(0)), false)
1500 for (idx,s) in tests.iter().enumerate() {
1501 run_renaming_test(s,idx);
1505 // no longer a fixme #8062: this test exposes a *potential* bug; our system does
1506 // not behave exactly like MTWT, but a conversation with Matthew Flatt
1507 // suggests that this can only occur in the presence of local-expand, which
1508 // we have no plans to support. ... unless it's needed for item hygiene....
1510 #[test] fn issue_8062(){
1512 &("fn main() {let hrcoo = 19; macro_rules! getx(()=>(hrcoo)); getx!();}",
1513 vec!(vec!(0)), true), 0)
1517 // the z flows into and out of two macros (g & f) along one path, and one
1518 // (just g) along the other, so the result of the whole thing should
1519 // be "let z_123 = 3; z_123"
1521 #[test] fn issue_6994(){
1523 &("macro_rules! g (($x:ident) =>
1524 ({macro_rules! f(($y:ident)=>({let $y=3;$x}));f!($x)}));
1526 vec!(vec!(0)),false),
1530 // match variable hygiene. Should expand into
1531 // fn z() {match 8 {x_1 => {match 9 {x_2 | x_2 if x_2 == x_1 => x_2 + x_1}}}}
1532 #[test] fn issue_9384(){
1534 &("macro_rules! bad_macro (($ex:expr) => ({match 9 {x | x if x == $ex => x + $ex}}));
1535 fn z() {match 8 {x => bad_macro!(x)}}",
1536 // NB: the third "binding" is the repeat of the second one.
1537 vec!(vec!(1,3),vec!(0,2),vec!(0,2)),
1542 // interpolated nodes weren't getting labeled.
1543 // should expand into
1544 // fn main(){let g1_1 = 13; g1_1}}
1545 #[test] fn pat_expand_issue_15221(){
1547 &("macro_rules! inner ( ($e:pat ) => ($e));
1548 macro_rules! outer ( ($e:pat ) => (inner!($e)));
1549 fn main() { let outer!(g) = 13; g;}",
1555 // create a really evil test case where a $x appears inside a binding of $x
1556 // but *shouldn't* bind because it was inserted by a different macro....
1557 // can't write this test case until we have macro-generating macros.
1559 // method arg hygiene
1560 // method expands to fn get_x(&self_0, x_1:int) {self_0 + self_2 + x_3 + x_1}
1561 #[test] fn method_arg_hygiene(){
1563 &("macro_rules! inject_x (()=>(x));
1564 macro_rules! inject_self (()=>(self));
1566 impl A{fn get_x(&self, x: int) {self + inject_self!() + inject_x!() + x;} }",
1567 vec!(vec!(0),vec!(3)),
1572 // ooh, got another bite?
1573 // expands to struct A; impl A {fn thingy(&self_1) {self_1;}}
1574 #[test] fn method_arg_hygiene_2(){
1577 macro_rules! add_method (($T:ty) =>
1578 (impl $T { fn thingy(&self) {self;} }));
1586 // expands to fn q(x_1:int){fn g(x_2:int){x_2 + x_1};}
1587 #[test] fn issue_9383(){
1589 &("macro_rules! bad_macro (($ex:expr) => (fn g(x:int){ x + $ex }));
1590 fn q(x:int) { bad_macro!(x); }",
1591 vec!(vec!(1),vec!(0)),true),
1595 // closure arg hygiene (ExprClosure)
1596 // expands to fn f(){(|x_1 : int| {(x_2 + x_1)})(3);}
1597 #[test] fn closure_arg_hygiene(){
1599 &("macro_rules! inject_x (()=>(x));
1600 fn f(){(|x : int| {(inject_x!() + x)})(3);}",
1606 // macro_rules in method position. Sadly, unimplemented.
1607 #[test] fn macro_in_method_posn(){
1609 "macro_rules! my_method (() => (fn thirteen(&self) -> int {13}));
1611 impl A{ my_method!(); }
1612 fn f(){A.thirteen;}".to_string());
1615 // another nested macro
1616 // expands to impl Entries {fn size_hint(&self_1) {self_1;}
1617 #[test] fn item_macro_workaround(){
1619 &("macro_rules! item { ($i:item) => {$i}}
1621 macro_rules! iterator_impl {
1622 () => { item!( impl Entries { fn size_hint(&self) { self;}});}}
1623 iterator_impl! { }",
1624 vec!(vec!(0)), true),
1628 // run one of the renaming tests
1629 fn run_renaming_test(t: &RenamingTest, test_idx: uint) {
1630 let invalid_name = token::special_idents::invalid.name;
1631 let (teststr, bound_connections, bound_ident_check) = match *t {
1632 (ref str,ref conns, bic) => (str.to_string(), conns.clone(), bic)
1634 let cr = expand_crate_str(teststr.to_string());
1635 let bindings = crate_bindings(&cr);
1636 let varrefs = crate_varrefs(&cr);
1638 // must be one check clause for each binding:
1639 assert_eq!(bindings.len(),bound_connections.len());
1640 for (binding_idx,shouldmatch) in bound_connections.iter().enumerate() {
1641 let binding_name = mtwt::resolve(bindings[binding_idx]);
1642 let binding_marks = mtwt::marksof(bindings[binding_idx].ctxt, invalid_name);
1643 // shouldmatch can't name varrefs that don't exist:
1644 assert!((shouldmatch.len() == 0) ||
1645 (varrefs.len() > *shouldmatch.iter().max().unwrap()));
1646 for (idx,varref) in varrefs.iter().enumerate() {
1647 let print_hygiene_debug_info = |&:| {
1648 // good lord, you can't make a path with 0 segments, can you?
1649 let final_varref_ident = match varref.segments.last() {
1650 Some(pathsegment) => pathsegment.identifier,
1651 None => panic!("varref with 0 path segments?")
1653 let varref_name = mtwt::resolve(final_varref_ident);
1654 let varref_idents : Vec<ast::Ident>
1655 = varref.segments.iter().map(|s| s.identifier)
1657 println!("varref #{}: {}, resolves to {}",idx, varref_idents, varref_name);
1658 let string = token::get_ident(final_varref_ident);
1659 println!("varref's first segment's string: \"{}\"", string.get());
1660 println!("binding #{}: {}, resolves to {}",
1661 binding_idx, bindings[binding_idx], binding_name);
1662 mtwt::with_sctable(|x| mtwt::display_sctable(x));
1664 if shouldmatch.contains(&idx) {
1665 // it should be a path of length 1, and it should
1666 // be free-identifier=? or bound-identifier=? to the given binding
1667 assert_eq!(varref.segments.len(),1);
1668 let varref_name = mtwt::resolve(varref.segments[0].identifier);
1669 let varref_marks = mtwt::marksof(varref.segments[0]
1673 if !(varref_name==binding_name) {
1674 println!("uh oh, should match but doesn't:");
1675 print_hygiene_debug_info();
1677 assert_eq!(varref_name,binding_name);
1678 if bound_ident_check {
1679 // we're checking bound-identifier=?, and the marks
1680 // should be the same, too:
1681 assert_eq!(varref_marks,binding_marks.clone());
1684 let varref_name = mtwt::resolve(varref.segments[0].identifier);
1685 let fail = (varref.segments.len() == 1)
1686 && (varref_name == binding_name);
1689 println!("failure on test {}",test_idx);
1690 println!("text of test case: \"{}\"", teststr);
1692 println!("uh oh, matches but shouldn't:");
1693 print_hygiene_debug_info();
1701 #[test] fn fmt_in_macro_used_inside_module_macro() {
1702 let crate_str = "macro_rules! fmt_wrap(($b:expr)=>($b.to_string()));
1703 macro_rules! foo_module (() => (mod generated { fn a() { let xx = 147; fmt_wrap!(xx);}}));
1706 let cr = expand_crate_str(crate_str);
1707 // find the xx binding
1708 let bindings = crate_bindings(&cr);
1709 let cxbinds: Vec<&ast::Ident> =
1710 bindings.iter().filter(|b| {
1711 let ident = token::get_ident(**b);
1712 let string = ident.get();
1715 let cxbinds: &[&ast::Ident] = cxbinds[];
1716 let cxbind = match cxbinds {
1718 _ => panic!("expected just one binding for ext_cx")
1720 let resolved_binding = mtwt::resolve(*cxbind);
1721 let varrefs = crate_varrefs(&cr);
1723 // the xx binding should bind all of the xx varrefs:
1724 for (idx,v) in varrefs.iter().filter(|p| {
1725 p.segments.len() == 1
1726 && "xx" == token::get_ident(p.segments[0].identifier).get()
1728 if mtwt::resolve(v.segments[0].identifier) != resolved_binding {
1729 println!("uh oh, xx binding didn't match xx varref:");
1730 println!("this is xx varref \\# {}", idx);
1731 println!("binding: {}", cxbind);
1732 println!("resolves to: {}", resolved_binding);
1733 println!("varref: {}", v.segments[0].identifier);
1734 println!("resolves to: {}",
1735 mtwt::resolve(v.segments[0].identifier));
1736 mtwt::with_sctable(|x| mtwt::display_sctable(x));
1738 assert_eq!(mtwt::resolve(v.segments[0].identifier),
1745 let pat = string_to_pat(
1746 "(a,Foo{x:c @ (b,9),y:Bar(4,d)})".to_string());
1747 let idents = pattern_bindings(&*pat);
1748 assert_eq!(idents, strs_to_idents(vec!("a","c","b","d")));
1751 // test the list of identifier patterns gathered by the visitor. Note that
1752 // 'None' is listed as an identifier pattern because we don't yet know that
1753 // it's the name of a 0-ary variant, and that 'i' appears twice in succession.
1755 fn crate_bindings_test(){
1756 let the_crate = string_to_crate("fn main (a : int) -> int {|b| {
1757 match 34 {None => 3, Some(i) | i => j, Foo{k:z,l:y} => \"banana\"}} }".to_string());
1758 let idents = crate_bindings(&the_crate);
1759 assert_eq!(idents, strs_to_idents(vec!("a","b","None","i","i","z","y")));
1762 // test the IdentRenamer directly
1764 fn ident_renamer_test () {
1765 let the_crate = string_to_crate("fn f(x : int){let x = x; x}".to_string());
1766 let f_ident = token::str_to_ident("f");
1767 let x_ident = token::str_to_ident("x");
1768 let int_ident = token::str_to_ident("int");
1769 let renames = vec!((x_ident,Name(16)));
1770 let mut renamer = IdentRenamer{renames: &renames};
1771 let renamed_crate = renamer.fold_crate(the_crate);
1772 let idents = crate_idents(&renamed_crate);
1773 let resolved : Vec<ast::Name> = idents.iter().map(|id| mtwt::resolve(*id)).collect();
1774 assert_eq!(resolved,vec!(f_ident.name,Name(16),int_ident.name,Name(16),Name(16),Name(16)));
1777 // test the PatIdentRenamer; only PatIdents get renamed
1779 fn pat_ident_renamer_test () {
1780 let the_crate = string_to_crate("fn f(x : int){let x = x; x}".to_string());
1781 let f_ident = token::str_to_ident("f");
1782 let x_ident = token::str_to_ident("x");
1783 let int_ident = token::str_to_ident("int");
1784 let renames = vec!((x_ident,Name(16)));
1785 let mut renamer = PatIdentRenamer{renames: &renames};
1786 let renamed_crate = renamer.fold_crate(the_crate);
1787 let idents = crate_idents(&renamed_crate);
1788 let resolved : Vec<ast::Name> = idents.iter().map(|id| mtwt::resolve(*id)).collect();
1789 let x_name = x_ident.name;
1790 assert_eq!(resolved,vec!(f_ident.name,Name(16),int_ident.name,Name(16),x_name,x_name));