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|
// Copyright 2012-2014 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
use ast::{Block, Crate, DeclLocal, ExprMac, PatMac};
use ast::{Local, Ident, MacInvocTT};
use ast::{ItemMac, Mrk, Stmt, StmtDecl, StmtMac, StmtExpr, StmtSemi};
use ast::TokenTree;
use ast;
use ext::mtwt;
use ext::build::AstBuilder;
use attr;
use attr::AttrMetaMethods;
use codemap;
use codemap::{Span, Spanned, ExpnInfo, NameAndSpan, MacroBang, MacroAttribute};
use ext::base::*;
use fold;
use fold::*;
use parse;
use parse::token::{fresh_mark, fresh_name, intern};
use parse::token;
use ptr::P;
use util::small_vector::SmallVector;
use visit;
use visit::Visitor;
enum Either<L,R> {
Left(L),
Right(R)
}
pub fn expand_expr(e: P<ast::Expr>, fld: &mut MacroExpander) -> P<ast::Expr> {
e.and_then(|ast::Expr {id, node, span}| match node {
// expr_mac should really be expr_ext or something; it's the
// entry-point for all syntax extensions.
ast::ExprMac(mac) => {
let expanded_expr = match expand_mac_invoc(mac, span,
|r| r.make_expr(),
mark_expr, fld) {
Some(expr) => expr,
None => {
return DummyResult::raw_expr(span);
}
};
// Keep going, outside-in.
//
let fully_expanded = fld.fold_expr(expanded_expr);
fld.cx.bt_pop();
fully_expanded.map(|e| ast::Expr {
id: ast::DUMMY_NODE_ID,
node: e.node,
span: span,
})
}
ast::ExprWhile(cond, body, opt_ident) => {
let cond = fld.fold_expr(cond);
let (body, opt_ident) = expand_loop_block(body, opt_ident, fld);
fld.cx.expr(span, ast::ExprWhile(cond, body, opt_ident))
}
// Desugar ExprWhileLet
// From: `[opt_ident]: while let <pat> = <expr> <body>`
ast::ExprWhileLet(pat, expr, body, opt_ident) => {
// to:
//
// [opt_ident]: loop {
// match <expr> {
// <pat> => <body>,
// _ => break
// }
// }
// `<pat> => <body>`
let pat_arm = {
let body_expr = fld.cx.expr_block(body);
fld.cx.arm(pat.span, vec![pat], body_expr)
};
// `_ => break`
let break_arm = {
let pat_under = fld.cx.pat_wild(span);
let break_expr = fld.cx.expr_break(span);
fld.cx.arm(span, vec![pat_under], break_expr)
};
// `match <expr> { ... }`
let arms = vec![pat_arm, break_arm];
let match_expr = fld.cx.expr(span,
ast::ExprMatch(expr, arms, ast::MatchWhileLetDesugar));
// `[opt_ident]: loop { ... }`
let loop_block = fld.cx.block_expr(match_expr);
let (loop_block, opt_ident) = expand_loop_block(loop_block, opt_ident, fld);
fld.cx.expr(span, ast::ExprLoop(loop_block, opt_ident))
}
// Desugar ExprIfLet
// From: `if let <pat> = <expr> <body> [<elseopt>]`
ast::ExprIfLet(pat, expr, body, mut elseopt) => {
// to:
//
// match <expr> {
// <pat> => <body>,
// [_ if <elseopt_if_cond> => <elseopt_if_body>,]
// _ => [<elseopt> | ()]
// }
// `<pat> => <body>`
let pat_arm = {
let body_expr = fld.cx.expr_block(body);
fld.cx.arm(pat.span, vec![pat], body_expr)
};
// `[_ if <elseopt_if_cond> => <elseopt_if_body>,]`
let else_if_arms = {
let mut arms = vec![];
loop {
let elseopt_continue = elseopt
.and_then(|els| els.and_then(|els| match els.node {
// else if
ast::ExprIf(cond, then, elseopt) => {
let pat_under = fld.cx.pat_wild(span);
arms.push(ast::Arm {
attrs: vec![],
pats: vec![pat_under],
guard: Some(cond),
body: fld.cx.expr_block(then)
});
elseopt.map(|elseopt| (elseopt, true))
}
_ => Some((P(els), false))
}));
match elseopt_continue {
Some((e, true)) => {
elseopt = Some(e);
}
Some((e, false)) => {
elseopt = Some(e);
break;
}
None => {
elseopt = None;
break;
}
}
}
arms
};
// `_ => [<elseopt> | ()]`
let else_arm = {
let pat_under = fld.cx.pat_wild(span);
let else_expr = elseopt.unwrap_or_else(|| fld.cx.expr_lit(span, ast::LitNil));
fld.cx.arm(span, vec![pat_under], else_expr)
};
let mut arms = Vec::with_capacity(else_if_arms.len() + 2);
arms.push(pat_arm);
arms.push_all_move(else_if_arms);
arms.push(else_arm);
let match_expr = fld.cx.expr(span, ast::ExprMatch(expr, arms, ast::MatchIfLetDesugar));
fld.fold_expr(match_expr)
}
// Desugar support for ExprIfLet in the ExprIf else position
ast::ExprIf(cond, blk, elseopt) => {
let elseopt = elseopt.map(|els| els.and_then(|els| match els.node {
ast::ExprIfLet(..) => {
// wrap the if-let expr in a block
let span = els.span;
let blk = P(ast::Block {
view_items: vec![],
stmts: vec![],
expr: Some(P(els)),
id: ast::DUMMY_NODE_ID,
rules: ast::DefaultBlock,
span: span
});
fld.cx.expr_block(blk)
}
_ => P(els)
}));
let if_expr = fld.cx.expr(span, ast::ExprIf(cond, blk, elseopt));
if_expr.map(|e| noop_fold_expr(e, fld))
}
ast::ExprLoop(loop_block, opt_ident) => {
let (loop_block, opt_ident) = expand_loop_block(loop_block, opt_ident, fld);
fld.cx.expr(span, ast::ExprLoop(loop_block, opt_ident))
}
ast::ExprForLoop(pat, head, body, opt_ident) => {
let pat = fld.fold_pat(pat);
let head = fld.fold_expr(head);
let (body, opt_ident) = expand_loop_block(body, opt_ident, fld);
fld.cx.expr(span, ast::ExprForLoop(pat, head, body, opt_ident))
}
ast::ExprFnBlock(capture_clause, fn_decl, block) => {
let (rewritten_fn_decl, rewritten_block)
= expand_and_rename_fn_decl_and_block(fn_decl, block, fld);
let new_node = ast::ExprFnBlock(capture_clause,
rewritten_fn_decl,
rewritten_block);
P(ast::Expr{id:id, node: new_node, span: fld.new_span(span)})
}
ast::ExprProc(fn_decl, block) => {
let (rewritten_fn_decl, rewritten_block)
= expand_and_rename_fn_decl_and_block(fn_decl, block, fld);
let new_node = ast::ExprProc(rewritten_fn_decl, rewritten_block);
P(ast::Expr{id:id, node: new_node, span: fld.new_span(span)})
}
_ => {
P(noop_fold_expr(ast::Expr {
id: id,
node: node,
span: span
}, fld))
}
})
}
/// Expand a (not-ident-style) macro invocation. Returns the result
/// of expansion and the mark which must be applied to the result.
/// Our current interface doesn't allow us to apply the mark to the
/// result until after calling make_expr, make_items, etc.
fn expand_mac_invoc<T>(mac: ast::Mac, span: codemap::Span,
parse_thunk: |Box<MacResult>|->Option<T>,
mark_thunk: |T,Mrk|->T,
fld: &mut MacroExpander)
-> Option<T>
{
match mac.node {
// it would almost certainly be cleaner to pass the whole
// macro invocation in, rather than pulling it apart and
// marking the tts and the ctxt separately. This also goes
// for the other three macro invocation chunks of code
// in this file.
// Token-tree macros:
MacInvocTT(pth, tts, _) => {
if pth.segments.len() > 1u {
fld.cx.span_err(pth.span,
"expected macro name without module \
separators");
// let compilation continue
return None;
}
let extname = pth.segments.get(0).identifier;
let extnamestr = token::get_ident(extname);
match fld.cx.syntax_env.find(&extname.name) {
None => {
fld.cx.span_err(
pth.span,
format!("macro undefined: '{}!'",
extnamestr.get()).as_slice());
// let compilation continue
None
}
Some(rc) => match *rc {
NormalTT(ref expandfun, exp_span) => {
fld.cx.bt_push(ExpnInfo {
call_site: span,
callee: NameAndSpan {
name: extnamestr.get().to_string(),
format: MacroBang,
span: exp_span,
},
});
let fm = fresh_mark();
let marked_before = mark_tts(tts.as_slice(), fm);
// The span that we pass to the expanders we want to
// be the root of the call stack. That's the most
// relevant span and it's the actual invocation of
// the macro.
let mac_span = fld.cx.original_span();
let opt_parsed = {
let expanded = expandfun.expand(fld.cx,
mac_span,
marked_before.as_slice());
parse_thunk(expanded)
};
let parsed = match opt_parsed {
Some(e) => e,
None => {
fld.cx.span_err(
pth.span,
format!("non-expression macro in expression position: {}",
extnamestr.get().as_slice()
).as_slice());
return None;
}
};
Some(mark_thunk(parsed,fm))
}
_ => {
fld.cx.span_err(
pth.span,
format!("'{}' is not a tt-style macro",
extnamestr.get()).as_slice());
None
}
}
}
}
}
}
/// Rename loop label and expand its loop body
///
/// The renaming procedure for loop is different in the sense that the loop
/// body is in a block enclosed by loop head so the renaming of loop label
/// must be propagated to the enclosed context.
fn expand_loop_block(loop_block: P<Block>,
opt_ident: Option<Ident>,
fld: &mut MacroExpander) -> (P<Block>, Option<Ident>) {
match opt_ident {
Some(label) => {
let new_label = fresh_name(&label);
let rename = (label, new_label);
// The rename *must not* be added to the pending list of current
// syntax context otherwise an unrelated `break` or `continue` in
// the same context will pick that up in the deferred renaming pass
// and be renamed incorrectly.
let mut rename_list = vec!(rename);
let mut rename_fld = IdentRenamer{renames: &mut rename_list};
let renamed_ident = rename_fld.fold_ident(label);
// The rename *must* be added to the enclosed syntax context for
// `break` or `continue` to pick up because by definition they are
// in a block enclosed by loop head.
fld.cx.syntax_env.push_frame();
fld.cx.syntax_env.info().pending_renames.push(rename);
let expanded_block = expand_block_elts(loop_block, fld);
fld.cx.syntax_env.pop_frame();
(expanded_block, Some(renamed_ident))
}
None => (fld.fold_block(loop_block), opt_ident)
}
}
// eval $e with a new exts frame.
// must be a macro so that $e isn't evaluated too early.
macro_rules! with_exts_frame (
($extsboxexpr:expr,$macros_escape:expr,$e:expr) =>
({$extsboxexpr.push_frame();
$extsboxexpr.info().macros_escape = $macros_escape;
let result = $e;
$extsboxexpr.pop_frame();
result
})
)
// When we enter a module, record it, for the sake of `module!`
pub fn expand_item(it: P<ast::Item>, fld: &mut MacroExpander)
-> SmallVector<P<ast::Item>> {
let it = expand_item_modifiers(it, fld);
let mut decorator_items = SmallVector::zero();
let mut new_attrs = Vec::new();
for attr in it.attrs.iter() {
let mname = attr.name();
match fld.cx.syntax_env.find(&intern(mname.get())) {
Some(rc) => match *rc {
Decorator(ref dec) => {
attr::mark_used(attr);
fld.cx.bt_push(ExpnInfo {
call_site: attr.span,
callee: NameAndSpan {
name: mname.get().to_string(),
format: MacroAttribute,
span: None
}
});
// we'd ideally decorator_items.push_all(expand_item(item, fld)),
// but that double-mut-borrows fld
let mut items: SmallVector<P<ast::Item>> = SmallVector::zero();
dec.expand(fld.cx, attr.span, &*attr.node.value, &*it,
|item| items.push(item));
decorator_items.extend(items.into_iter()
.flat_map(|item| expand_item(item, fld).into_iter()));
fld.cx.bt_pop();
}
_ => new_attrs.push((*attr).clone()),
},
_ => new_attrs.push((*attr).clone()),
}
}
let mut new_items = match it.node {
ast::ItemMac(..) => expand_item_mac(it, fld),
ast::ItemMod(_) | ast::ItemForeignMod(_) => {
fld.cx.mod_push(it.ident);
let macro_escape = contains_macro_escape(new_attrs.as_slice());
let result = with_exts_frame!(fld.cx.syntax_env,
macro_escape,
noop_fold_item(it, fld));
fld.cx.mod_pop();
result
},
_ => {
let it = P(ast::Item {
attrs: new_attrs,
..(*it).clone()
});
noop_fold_item(it, fld)
}
};
new_items.push_all(decorator_items);
new_items
}
fn expand_item_modifiers(mut it: P<ast::Item>, fld: &mut MacroExpander)
-> P<ast::Item> {
// partition the attributes into ItemModifiers and others
let (modifiers, other_attrs) = it.attrs.partitioned(|attr| {
match fld.cx.syntax_env.find(&intern(attr.name().get())) {
Some(rc) => match *rc { Modifier(_) => true, _ => false },
_ => false
}
});
// update the attrs, leave everything else alone. Is this mutation really a good idea?
it = P(ast::Item {
attrs: other_attrs,
..(*it).clone()
});
if modifiers.is_empty() {
return it;
}
for attr in modifiers.iter() {
let mname = attr.name();
match fld.cx.syntax_env.find(&intern(mname.get())) {
Some(rc) => match *rc {
Modifier(ref mac) => {
attr::mark_used(attr);
fld.cx.bt_push(ExpnInfo {
call_site: attr.span,
callee: NameAndSpan {
name: mname.get().to_string(),
format: MacroAttribute,
span: None,
}
});
it = mac.expand(fld.cx, attr.span, &*attr.node.value, it);
fld.cx.bt_pop();
}
_ => unreachable!()
},
_ => unreachable!()
}
}
// expansion may have added new ItemModifiers
expand_item_modifiers(it, fld)
}
/// Expand item_underscore
fn expand_item_underscore(item: ast::Item_, fld: &mut MacroExpander) -> ast::Item_ {
match item {
ast::ItemFn(decl, fn_style, abi, generics, body) => {
let (rewritten_fn_decl, rewritten_body)
= expand_and_rename_fn_decl_and_block(decl, body, fld);
let expanded_generics = fold::noop_fold_generics(generics,fld);
ast::ItemFn(rewritten_fn_decl, fn_style, abi, expanded_generics, rewritten_body)
}
_ => noop_fold_item_underscore(item, fld)
}
}
// does this attribute list contain "macro_escape" ?
fn contains_macro_escape(attrs: &[ast::Attribute]) -> bool {
attr::contains_name(attrs, "macro_escape")
}
// Support for item-position macro invocations, exactly the same
// logic as for expression-position macro invocations.
pub fn expand_item_mac(it: P<ast::Item>, fld: &mut MacroExpander)
-> SmallVector<P<ast::Item>> {
let (extname, path_span, tts) = match it.node {
ItemMac(codemap::Spanned {
node: MacInvocTT(ref pth, ref tts, _),
..
}) => {
(pth.segments.get(0).identifier, pth.span, (*tts).clone())
}
_ => fld.cx.span_bug(it.span, "invalid item macro invocation")
};
let extnamestr = token::get_ident(extname);
let fm = fresh_mark();
let def_or_items = {
let mut expanded = match fld.cx.syntax_env.find(&extname.name) {
None => {
fld.cx.span_err(path_span,
format!("macro undefined: '{}!'",
extnamestr).as_slice());
// let compilation continue
return SmallVector::zero();
}
Some(rc) => match *rc {
NormalTT(ref expander, span) => {
if it.ident.name != parse::token::special_idents::invalid.name {
fld.cx
.span_err(path_span,
format!("macro {}! expects no ident argument, \
given '{}'",
extnamestr,
token::get_ident(it.ident)).as_slice());
return SmallVector::zero();
}
fld.cx.bt_push(ExpnInfo {
call_site: it.span,
callee: NameAndSpan {
name: extnamestr.get().to_string(),
format: MacroBang,
span: span
}
});
// mark before expansion:
let marked_before = mark_tts(tts.as_slice(), fm);
expander.expand(fld.cx, it.span, marked_before.as_slice())
}
IdentTT(ref expander, span) => {
if it.ident.name == parse::token::special_idents::invalid.name {
fld.cx.span_err(path_span,
format!("macro {}! expects an ident argument",
extnamestr.get()).as_slice());
return SmallVector::zero();
}
fld.cx.bt_push(ExpnInfo {
call_site: it.span,
callee: NameAndSpan {
name: extnamestr.get().to_string(),
format: MacroBang,
span: span
}
});
// mark before expansion:
let marked_tts = mark_tts(tts.as_slice(), fm);
expander.expand(fld.cx, it.span, it.ident, marked_tts)
}
LetSyntaxTT(ref expander, span) => {
if it.ident.name == parse::token::special_idents::invalid.name {
fld.cx.span_err(path_span,
format!("macro {}! expects an ident argument",
extnamestr.get()).as_slice());
return SmallVector::zero();
}
fld.cx.bt_push(ExpnInfo {
call_site: it.span,
callee: NameAndSpan {
name: extnamestr.get().to_string(),
format: MacroBang,
span: span
}
});
// DON'T mark before expansion:
expander.expand(fld.cx, it.span, it.ident, tts)
}
_ => {
fld.cx.span_err(it.span,
format!("{}! is not legal in item position",
extnamestr.get()).as_slice());
return SmallVector::zero();
}
}
};
match expanded.make_def() {
Some(def) => Left(def),
None => Right(expanded.make_items())
}
};
let items = match def_or_items {
Left(MacroDef { name, ext }) => {
// hidden invariant: this should only be possible as the
// result of expanding a LetSyntaxTT, and thus doesn't
// need to be marked. Not that it could be marked anyway.
// create issue to recommend refactoring here?
fld.cx.syntax_env.insert(intern(name.as_slice()), ext);
if attr::contains_name(it.attrs.as_slice(), "macro_export") {
fld.cx.exported_macros.push(it);
}
SmallVector::zero()
}
Right(Some(items)) => {
items.into_iter()
.map(|i| mark_item(i, fm))
.flat_map(|i| fld.fold_item(i).into_iter())
.collect()
}
Right(None) => {
fld.cx.span_err(path_span,
format!("non-item macro in item position: {}",
extnamestr.get()).as_slice());
return SmallVector::zero();
}
};
fld.cx.bt_pop();
items
}
/// Expand a stmt
//
// I don't understand why this returns a vector... it looks like we're
// half done adding machinery to allow macros to expand into multiple statements.
fn expand_stmt(s: Stmt, fld: &mut MacroExpander) -> SmallVector<P<Stmt>> {
let (mac, semi) = match s.node {
StmtMac(mac, semi) => (mac, semi),
_ => return expand_non_macro_stmt(s, fld)
};
let expanded_stmt = match expand_mac_invoc(mac, s.span,
|r| r.make_stmt(),
mark_stmt, fld) {
Some(stmt) => stmt,
None => {
return SmallVector::zero();
}
};
// Keep going, outside-in.
let fully_expanded = fld.fold_stmt(expanded_stmt);
fld.cx.bt_pop();
if semi {
fully_expanded.into_iter().map(|s| s.map(|Spanned {node, span}| {
Spanned {
node: match node {
StmtExpr(e, stmt_id) => StmtSemi(e, stmt_id),
_ => node /* might already have a semi */
},
span: span
}
})).collect()
} else {
fully_expanded
}
}
// expand a non-macro stmt. this is essentially the fallthrough for
// expand_stmt, above.
fn expand_non_macro_stmt(Spanned {node, span: stmt_span}: Stmt, fld: &mut MacroExpander)
-> SmallVector<P<Stmt>> {
// is it a let?
match node {
StmtDecl(decl, node_id) => decl.and_then(|Spanned {node: decl, span}| match decl {
DeclLocal(local) => {
// take it apart:
let rewritten_local = local.map(|Local {id, pat, ty, init, source, span}| {
// expand the ty since TyFixedLengthVec contains an Expr
// and thus may have a macro use
let expanded_ty = fld.fold_ty(ty);
// expand the pat (it might contain macro uses):
let expanded_pat = fld.fold_pat(pat);
// find the PatIdents in the pattern:
// oh dear heaven... this is going to include the enum
// names, as well... but that should be okay, as long as
// the new names are gensyms for the old ones.
// generate fresh names, push them to a new pending list
let idents = pattern_bindings(&*expanded_pat);
let mut new_pending_renames =
idents.iter().map(|ident| (*ident, fresh_name(ident))).collect();
// rewrite the pattern using the new names (the old
// ones have already been applied):
let rewritten_pat = {
// nested binding to allow borrow to expire:
let mut rename_fld = IdentRenamer{renames: &mut new_pending_renames};
rename_fld.fold_pat(expanded_pat)
};
// add them to the existing pending renames:
fld.cx.syntax_env.info().pending_renames.push_all_move(new_pending_renames);
Local {
id: id,
ty: expanded_ty,
pat: rewritten_pat,
// also, don't forget to expand the init:
init: init.map(|e| fld.fold_expr(e)),
source: source,
span: span
}
});
SmallVector::one(P(Spanned {
node: StmtDecl(P(Spanned {
node: DeclLocal(rewritten_local),
span: span
}),
node_id),
span: stmt_span
}))
}
_ => {
noop_fold_stmt(Spanned {
node: StmtDecl(P(Spanned {
node: decl,
span: span
}),
node_id),
span: stmt_span
}, fld)
}
}),
_ => {
noop_fold_stmt(Spanned {
node: node,
span: stmt_span
}, fld)
}
}
}
// expand the arm of a 'match', renaming for macro hygiene
fn expand_arm(arm: ast::Arm, fld: &mut MacroExpander) -> ast::Arm {
// expand pats... they might contain macro uses:
let expanded_pats = arm.pats.move_map(|pat| fld.fold_pat(pat));
if expanded_pats.len() == 0 {
fail!("encountered match arm with 0 patterns");
}
// all of the pats must have the same set of bindings, so use the
// first one to extract them and generate new names:
let idents = pattern_bindings(&**expanded_pats.get(0));
let new_renames = idents.into_iter().map(|id| (id, fresh_name(&id))).collect();
// apply the renaming, but only to the PatIdents:
let mut rename_pats_fld = PatIdentRenamer{renames:&new_renames};
let rewritten_pats = expanded_pats.move_map(|pat| rename_pats_fld.fold_pat(pat));
// apply renaming and then expansion to the guard and the body:
let mut rename_fld = IdentRenamer{renames:&new_renames};
let rewritten_guard =
arm.guard.map(|g| fld.fold_expr(rename_fld.fold_expr(g)));
let rewritten_body = fld.fold_expr(rename_fld.fold_expr(arm.body));
ast::Arm {
attrs: arm.attrs.move_map(|x| fld.fold_attribute(x)),
pats: rewritten_pats,
guard: rewritten_guard,
body: rewritten_body,
}
}
/// A visitor that extracts the PatIdent (binding) paths
/// from a given thingy and puts them in a mutable
/// array
#[deriving(Clone)]
struct PatIdentFinder {
ident_accumulator: Vec<ast::Ident>
}
impl<'v> Visitor<'v> for PatIdentFinder {
fn visit_pat(&mut self, pattern: &ast::Pat) {
match *pattern {
ast::Pat { id: _, node: ast::PatIdent(_, ref path1, ref inner), span: _ } => {
self.ident_accumulator.push(path1.node);
// visit optional subpattern of PatIdent:
for subpat in inner.iter() {
self.visit_pat(&**subpat)
}
}
// use the default traversal for non-PatIdents
_ => visit::walk_pat(self, pattern)
}
}
}
/// find the PatIdent paths in a pattern
fn pattern_bindings(pat: &ast::Pat) -> Vec<ast::Ident> {
let mut name_finder = PatIdentFinder{ident_accumulator:Vec::new()};
name_finder.visit_pat(pat);
name_finder.ident_accumulator
}
/// find the PatIdent paths in a
fn fn_decl_arg_bindings(fn_decl: &ast::FnDecl) -> Vec<ast::Ident> {
let mut pat_idents = PatIdentFinder{ident_accumulator:Vec::new()};
for arg in fn_decl.inputs.iter() {
pat_idents.visit_pat(&*arg.pat);
}
pat_idents.ident_accumulator
}
// expand a block. pushes a new exts_frame, then calls expand_block_elts
pub fn expand_block(blk: P<Block>, fld: &mut MacroExpander) -> P<Block> {
// see note below about treatment of exts table
with_exts_frame!(fld.cx.syntax_env,false,
expand_block_elts(blk, fld))
}
// expand the elements of a block.
pub fn expand_block_elts(b: P<Block>, fld: &mut MacroExpander) -> P<Block> {
b.map(|Block {id, view_items, stmts, expr, rules, span}| {
let new_view_items = view_items.into_iter().map(|x| fld.fold_view_item(x)).collect();
let new_stmts = stmts.into_iter().flat_map(|x| {
// perform all pending renames
let renamed_stmt = {
let pending_renames = &mut fld.cx.syntax_env.info().pending_renames;
let mut rename_fld = IdentRenamer{renames:pending_renames};
rename_fld.fold_stmt(x).expect_one("rename_fold didn't return one value")
};
// expand macros in the statement
fld.fold_stmt(renamed_stmt).into_iter()
}).collect();
let new_expr = expr.map(|x| {
let expr = {
let pending_renames = &mut fld.cx.syntax_env.info().pending_renames;
let mut rename_fld = IdentRenamer{renames:pending_renames};
rename_fld.fold_expr(x)
};
fld.fold_expr(expr)
});
Block {
id: fld.new_id(id),
view_items: new_view_items,
stmts: new_stmts,
expr: new_expr,
rules: rules,
span: span
}
})
}
fn expand_pat(p: P<ast::Pat>, fld: &mut MacroExpander) -> P<ast::Pat> {
match p.node {
PatMac(_) => {}
_ => return noop_fold_pat(p, fld)
}
p.map(|ast::Pat {node, span, ..}| {
let (pth, tts) = match node {
PatMac(mac) => match mac.node {
MacInvocTT(pth, tts, _) => {
(pth, tts)
}
},
_ => unreachable!()
};
if pth.segments.len() > 1u {
fld.cx.span_err(pth.span, "expected macro name without module separators");
return DummyResult::raw_pat(span);
}
let extname = pth.segments.get(0).identifier;
let extnamestr = token::get_ident(extname);
let marked_after = match fld.cx.syntax_env.find(&extname.name) {
None => {
fld.cx.span_err(pth.span,
format!("macro undefined: '{}!'",
extnamestr).as_slice());
// let compilation continue
return DummyResult::raw_pat(span);
}
Some(rc) => match *rc {
NormalTT(ref expander, tt_span) => {
fld.cx.bt_push(ExpnInfo {
call_site: span,
callee: NameAndSpan {
name: extnamestr.get().to_string(),
format: MacroBang,
span: tt_span
}
});
let fm = fresh_mark();
let marked_before = mark_tts(tts.as_slice(), fm);
let mac_span = fld.cx.original_span();
let expanded = match expander.expand(fld.cx,
mac_span,
marked_before.as_slice()).make_pat() {
Some(e) => e,
None => {
fld.cx.span_err(
pth.span,
format!(
"non-pattern macro in pattern position: {}",
extnamestr.get()
).as_slice()
);
return DummyResult::raw_pat(span);
}
};
// mark after:
mark_pat(expanded,fm)
}
_ => {
fld.cx.span_err(span,
format!("{}! is not legal in pattern position",
extnamestr.get()).as_slice());
return DummyResult::raw_pat(span);
}
}
};
let fully_expanded =
fld.fold_pat(marked_after).node.clone();
fld.cx.bt_pop();
ast::Pat {
id: ast::DUMMY_NODE_ID,
node: fully_expanded,
span: span
}
})
}
/// A tree-folder that applies every rename in its (mutable) list
/// to every identifier, including both bindings and varrefs
/// (and lots of things that will turn out to be neither)
pub struct IdentRenamer<'a> {
renames: &'a mtwt::RenameList,
}
impl<'a> Folder for IdentRenamer<'a> {
fn fold_ident(&mut self, id: Ident) -> Ident {
Ident {
name: id.name,
ctxt: mtwt::apply_renames(self.renames, id.ctxt),
}
}
fn fold_mac(&mut self, macro: ast::Mac) -> ast::Mac {
fold::noop_fold_mac(macro, self)
}
}
/// A tree-folder that applies every rename in its list to
/// the idents that are in PatIdent patterns. This is more narrowly
/// focused than IdentRenamer, and is needed for FnDecl,
/// where we want to rename the args but not the fn name or the generics etc.
pub struct PatIdentRenamer<'a> {
renames: &'a mtwt::RenameList,
}
impl<'a> Folder for PatIdentRenamer<'a> {
fn fold_pat(&mut self, pat: P<ast::Pat>) -> P<ast::Pat> {
match pat.node {
ast::PatIdent(..) => {},
_ => return noop_fold_pat(pat, self)
}
pat.map(|ast::Pat {id, node, span}| match node {
ast::PatIdent(binding_mode, Spanned{span: sp, node: ident}, sub) => {
let new_ident = Ident{name: ident.name,
ctxt: mtwt::apply_renames(self.renames, ident.ctxt)};
let new_node =
ast::PatIdent(binding_mode,
Spanned{span: self.new_span(sp), node: new_ident},
sub.map(|p| self.fold_pat(p)));
ast::Pat {
id: id,
node: new_node,
span: self.new_span(span)
}
},
_ => unreachable!()
})
}
fn fold_mac(&mut self, macro: ast::Mac) -> ast::Mac {
fold::noop_fold_mac(macro, self)
}
}
// expand a method
fn expand_method(m: P<ast::Method>, fld: &mut MacroExpander) -> SmallVector<P<ast::Method>> {
m.and_then(|m| match m.node {
ast::MethDecl(ident,
generics,
abi,
explicit_self,
fn_style,
decl,
body,
vis) => {
let id = fld.new_id(m.id);
let (rewritten_fn_decl, rewritten_body)
= expand_and_rename_fn_decl_and_block(decl,body,fld);
SmallVector::one(P(ast::Method {
attrs: m.attrs.move_map(|a| fld.fold_attribute(a)),
id: id,
span: fld.new_span(m.span),
node: ast::MethDecl(fld.fold_ident(ident),
noop_fold_generics(generics, fld),
abi,
fld.fold_explicit_self(explicit_self),
fn_style,
rewritten_fn_decl,
rewritten_body,
vis)
}))
},
ast::MethMac(mac) => {
let maybe_new_methods =
expand_mac_invoc(mac, m.span,
|r| r.make_methods(),
|meths, mark| meths.move_map(|m| mark_method(m, mark)),
fld);
let new_methods = match maybe_new_methods {
Some(methods) => methods,
None => SmallVector::zero()
};
// expand again if necessary
let new_methods = new_methods.move_iter()
.flat_map(|m| fld.fold_method(m).into_iter()).collect();
fld.cx.bt_pop();
new_methods
}
})
}
/// Given a fn_decl and a block and a MacroExpander, expand the fn_decl, then use the
/// PatIdents in its arguments to perform renaming in the FnDecl and
/// the block, returning both the new FnDecl and the new Block.
fn expand_and_rename_fn_decl_and_block(fn_decl: P<ast::FnDecl>, block: P<ast::Block>,
fld: &mut MacroExpander)
-> (P<ast::FnDecl>, P<ast::Block>) {
let expanded_decl = fld.fold_fn_decl(fn_decl);
let idents = fn_decl_arg_bindings(&*expanded_decl);
let renames =
idents.iter().map(|id : &ast::Ident| (*id,fresh_name(id))).collect();
// first, a renamer for the PatIdents, for the fn_decl:
let mut rename_pat_fld = PatIdentRenamer{renames: &renames};
let rewritten_fn_decl = rename_pat_fld.fold_fn_decl(expanded_decl);
// now, a renamer for *all* idents, for the body:
let mut rename_fld = IdentRenamer{renames: &renames};
let rewritten_body = fld.fold_block(rename_fld.fold_block(block));
(rewritten_fn_decl,rewritten_body)
}
/// A tree-folder that performs macro expansion
pub struct MacroExpander<'a, 'b:'a> {
pub cx: &'a mut ExtCtxt<'b>,
}
impl<'a, 'b> Folder for MacroExpander<'a, 'b> {
fn fold_expr(&mut self, expr: P<ast::Expr>) -> P<ast::Expr> {
expand_expr(expr, self)
}
fn fold_pat(&mut self, pat: P<ast::Pat>) -> P<ast::Pat> {
expand_pat(pat, self)
}
fn fold_item(&mut self, item: P<ast::Item>) -> SmallVector<P<ast::Item>> {
expand_item(item, self)
}
fn fold_item_underscore(&mut self, item: ast::Item_) -> ast::Item_ {
expand_item_underscore(item, self)
}
fn fold_stmt(&mut self, stmt: P<ast::Stmt>) -> SmallVector<P<ast::Stmt>> {
stmt.and_then(|stmt| expand_stmt(stmt, self))
}
fn fold_block(&mut self, block: P<Block>) -> P<Block> {
expand_block(block, self)
}
fn fold_arm(&mut self, arm: ast::Arm) -> ast::Arm {
expand_arm(arm, self)
}
fn fold_method(&mut self, method: P<ast::Method>) -> SmallVector<P<ast::Method>> {
expand_method(method, self)
}
fn new_span(&mut self, span: Span) -> Span {
new_span(self.cx, span)
}
}
fn new_span(cx: &ExtCtxt, sp: Span) -> Span {
/* this discards information in the case of macro-defining macros */
Span {
lo: sp.lo,
hi: sp.hi,
expn_id: cx.backtrace(),
}
}
pub struct ExpansionConfig {
pub crate_name: String,
pub deriving_hash_type_parameter: bool,
pub enable_quotes: bool,
pub recursion_limit: uint,
}
impl ExpansionConfig {
pub fn default(crate_name: String) -> ExpansionConfig {
ExpansionConfig {
crate_name: crate_name,
deriving_hash_type_parameter: false,
enable_quotes: false,
recursion_limit: 64,
}
}
}
pub struct ExportedMacros {
pub crate_name: Ident,
pub macros: Vec<String>,
}
pub fn expand_crate(parse_sess: &parse::ParseSess,
cfg: ExpansionConfig,
// these are the macros being imported to this crate:
imported_macros: Vec<ExportedMacros>,
user_exts: Vec<NamedSyntaxExtension>,
c: Crate) -> Crate {
let mut cx = ExtCtxt::new(parse_sess, c.config.clone(), cfg);
let mut expander = MacroExpander {
cx: &mut cx,
};
for ExportedMacros { crate_name, macros } in imported_macros.into_iter() {
let name = format!("<{} macros>", token::get_ident(crate_name))
.into_string();
for source in macros.into_iter() {
let item = parse::parse_item_from_source_str(name.clone(),
source,
expander.cx.cfg(),
expander.cx.parse_sess())
.expect("expected a serialized item");
expand_item_mac(item, &mut expander);
}
}
for (name, extension) in user_exts.into_iter() {
expander.cx.syntax_env.insert(name, extension);
}
let mut ret = expander.fold_crate(c);
ret.exported_macros = expander.cx.exported_macros.clone();
parse_sess.span_diagnostic.handler().abort_if_errors();
return ret;
}
// HYGIENIC CONTEXT EXTENSION:
// all of these functions are for walking over
// ASTs and making some change to the context of every
// element that has one. a CtxtFn is a trait-ified
// version of a closure in (SyntaxContext -> SyntaxContext).
// the ones defined here include:
// Marker - add a mark to a context
// A Marker adds the given mark to the syntax context
struct Marker { mark: Mrk }
impl Folder for Marker {
fn fold_ident(&mut self, id: Ident) -> Ident {
ast::Ident {
name: id.name,
ctxt: mtwt::apply_mark(self.mark, id.ctxt)
}
}
fn fold_mac(&mut self, Spanned {node, span}: ast::Mac) -> ast::Mac {
Spanned {
node: match node {
MacInvocTT(path, tts, ctxt) => {
MacInvocTT(self.fold_path(path),
self.fold_tts(tts.as_slice()),
mtwt::apply_mark(self.mark, ctxt))
}
},
span: span,
}
}
}
// apply a given mark to the given token trees. Used prior to expansion of a macro.
fn mark_tts(tts: &[TokenTree], m: Mrk) -> Vec<TokenTree> {
noop_fold_tts(tts, &mut Marker{mark:m})
}
// apply a given mark to the given expr. Used following the expansion of a macro.
fn mark_expr(expr: P<ast::Expr>, m: Mrk) -> P<ast::Expr> {
Marker{mark:m}.fold_expr(expr)
}
// apply a given mark to the given pattern. Used following the expansion of a macro.
fn mark_pat(pat: P<ast::Pat>, m: Mrk) -> P<ast::Pat> {
Marker{mark:m}.fold_pat(pat)
}
// apply a given mark to the given stmt. Used following the expansion of a macro.
fn mark_stmt(expr: P<ast::Stmt>, m: Mrk) -> P<ast::Stmt> {
Marker{mark:m}.fold_stmt(expr)
.expect_one("marking a stmt didn't return exactly one stmt")
}
// apply a given mark to the given item. Used following the expansion of a macro.
fn mark_item(expr: P<ast::Item>, m: Mrk) -> P<ast::Item> {
Marker{mark:m}.fold_item(expr)
.expect_one("marking an item didn't return exactly one item")
}
// apply a given mark to the given item. Used following the expansion of a macro.
fn mark_method(expr: P<ast::Method>, m: Mrk) -> P<ast::Method> {
Marker{mark:m}.fold_method(expr)
.expect_one("marking an item didn't return exactly one method")
}
/// Check that there are no macro invocations left in the AST:
pub fn check_for_macros(sess: &parse::ParseSess, krate: &ast::Crate) {
visit::walk_crate(&mut MacroExterminator{sess:sess}, krate);
}
/// A visitor that ensures that no macro invocations remain in an AST.
struct MacroExterminator<'a>{
sess: &'a parse::ParseSess
}
impl<'a, 'v> Visitor<'v> for MacroExterminator<'a> {
fn visit_mac(&mut self, macro: &ast::Mac) {
self.sess.span_diagnostic.span_bug(macro.span,
"macro exterminator: expected AST \
with no macro invocations");
}
}
#[cfg(test)]
mod test {
use super::{pattern_bindings, expand_crate, contains_macro_escape};
use super::{PatIdentFinder, IdentRenamer, PatIdentRenamer, ExpansionConfig};
use ast;
use ast::{Attribute_, AttrOuter, MetaWord, Name};
use attr;
use codemap;
use codemap::Spanned;
use ext::mtwt;
use fold::Folder;
use parse;
use parse::token;
use ptr::P;
use util::parser_testing::{string_to_parser};
use util::parser_testing::{string_to_pat, string_to_crate, strs_to_idents};
use visit;
use visit::Visitor;
// a visitor that extracts the paths
// from a given thingy and puts them in a mutable
// array (passed in to the traversal)
#[deriving(Clone)]
struct PathExprFinderContext {
path_accumulator: Vec<ast::Path> ,
}
impl<'v> Visitor<'v> for PathExprFinderContext {
fn visit_expr(&mut self, expr: &ast::Expr) {
match expr.node {
ast::ExprPath(ref p) => {
self.path_accumulator.push(p.clone());
// not calling visit_path, but it should be fine.
}
_ => visit::walk_expr(self, expr)
}
}
}
// find the variable references in a crate
fn crate_varrefs(the_crate : &ast::Crate) -> Vec<ast::Path> {
let mut path_finder = PathExprFinderContext{path_accumulator:Vec::new()};
visit::walk_crate(&mut path_finder, the_crate);
path_finder.path_accumulator
}
/// A Visitor that extracts the identifiers from a thingy.
// as a side note, I'm starting to want to abstract over these....
struct IdentFinder {
ident_accumulator: Vec<ast::Ident>
}
impl<'v> Visitor<'v> for IdentFinder {
fn visit_ident(&mut self, _: codemap::Span, id: ast::Ident){
self.ident_accumulator.push(id);
}
}
/// Find the idents in a crate
fn crate_idents(the_crate: &ast::Crate) -> Vec<ast::Ident> {
let mut ident_finder = IdentFinder{ident_accumulator: Vec::new()};
visit::walk_crate(&mut ident_finder, the_crate);
ident_finder.ident_accumulator
}
// these following tests are quite fragile, in that they don't test what
// *kind* of failure occurs.
fn test_ecfg() -> ExpansionConfig {
ExpansionConfig::default("test".to_string())
}
// make sure that macros can't escape fns
#[should_fail]
#[test] fn macros_cant_escape_fns_test () {
let src = "fn bogus() {macro_rules! z (() => (3+4))}\
fn inty() -> int { z!() }".to_string();
let sess = parse::new_parse_sess();
let crate_ast = parse::parse_crate_from_source_str(
"<test>".to_string(),
src,
Vec::new(), &sess);
// should fail:
expand_crate(&sess,test_ecfg(),vec!(),vec!(),crate_ast);
}
// make sure that macros can't escape modules
#[should_fail]
#[test] fn macros_cant_escape_mods_test () {
let src = "mod foo {macro_rules! z (() => (3+4))}\
fn inty() -> int { z!() }".to_string();
let sess = parse::new_parse_sess();
let crate_ast = parse::parse_crate_from_source_str(
"<test>".to_string(),
src,
Vec::new(), &sess);
expand_crate(&sess,test_ecfg(),vec!(),vec!(),crate_ast);
}
// macro_escape modules should allow macros to escape
#[test] fn macros_can_escape_flattened_mods_test () {
let src = "#[macro_escape] mod foo {macro_rules! z (() => (3+4))}\
fn inty() -> int { z!() }".to_string();
let sess = parse::new_parse_sess();
let crate_ast = parse::parse_crate_from_source_str(
"<test>".to_string(),
src,
Vec::new(), &sess);
expand_crate(&sess, test_ecfg(), vec!(), vec!(), crate_ast);
}
#[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 = vec!(attr1.clone(), escape_attr, attr2.clone());
assert_eq!(contains_macro_escape(attrs1.as_slice()),true);
let attrs2 = vec!(attr1,attr2);
assert_eq!(contains_macro_escape(attrs2.as_slice()),false);
}
// make a MetaWord outer attribute with the given name
fn make_dummy_attr(s: &str) -> ast::Attribute {
Spanned {
span:codemap::DUMMY_SP,
node: Attribute_ {
id: attr::mk_attr_id(),
style: AttrOuter,
value: P(Spanned {
node: MetaWord(token::intern_and_get_ident(s)),
span: codemap::DUMMY_SP,
}),
is_sugared_doc: false,
}
}
}
fn expand_crate_str(crate_str: String) -> ast::Crate {
let ps = parse::new_parse_sess();
let crate_ast = string_to_parser(&ps, crate_str).parse_crate_mod();
// the cfg argument actually does matter, here...
expand_crate(&ps,test_ecfg(),vec!(),vec!(),crate_ast)
}
// find the pat_ident paths in a crate
fn crate_bindings(the_crate : &ast::Crate) -> Vec<ast::Ident> {
let mut name_finder = PatIdentFinder{ident_accumulator:Vec::new()};
visit::walk_crate(&mut name_finder, the_crate);
name_finder.ident_accumulator
}
#[test] fn macro_tokens_should_match(){
expand_crate_str(
"macro_rules! m((a)=>(13)) fn main(){m!(a);}".to_string());
}
// should be able to use a bound identifier as a literal in a macro definition:
#[test] fn self_macro_parsing(){
expand_crate_str(
"macro_rules! foo ((zz) => (287u;))
fn f(zz : int) {foo!(zz);}".to_string()
);
}
// renaming tests expand a crate and then check that the bindings match
// the right varrefs. The specification of the test case includes the
// text of the crate, and also an array of arrays. Each element in the
// outer array corresponds to a binding in the traversal of the AST
// induced by visit. Each of these arrays contains a list of indexes,
// interpreted as the varrefs in the varref traversal that this binding
// should match. So, for instance, in a program with two bindings and
// three varrefs, the array ~[~[1,2],~[0]] would indicate that the first
// binding should match the second two varrefs, and the second binding
// should match the first varref.
//
// Put differently; this is a sparse representation of a boolean matrix
// indicating which bindings capture which identifiers.
//
// Note also that this matrix is dependent on the implicit ordering of
// the bindings and the varrefs discovered by the name-finder and the path-finder.
//
// The comparisons are done post-mtwt-resolve, so we're comparing renamed
// names; differences in marks don't matter any more.
//
// oog... I also want tests that check "bound-identifier-=?". That is,
// not just "do these have the same name", but "do they have the same
// name *and* the same marks"? Understanding this is really pretty painful.
// in principle, you might want to control this boolean on a per-varref basis,
// but that would make things even harder to understand, and might not be
// necessary for thorough testing.
type RenamingTest = (&'static str, Vec<Vec<uint>>, bool);
#[test]
fn automatic_renaming () {
let tests: Vec<RenamingTest> =
vec!(// b & c should get new names throughout, in the expr too:
("fn a() -> int { let b = 13; let c = b; b+c }",
vec!(vec!(0,1),vec!(2)), false),
// both x's should be renamed (how is this causing a bug?)
("fn main () {let x: int = 13;x;}",
vec!(vec!(0)), false),
// the use of b after the + should be renamed, the other one not:
("macro_rules! f (($x:ident) => (b + $x)) fn a() -> int { let b = 13; f!(b)}",
vec!(vec!(1)), false),
// the b before the plus should not be renamed (requires marks)
("macro_rules! f (($x:ident) => ({let b=9; ($x + b)})) fn a() -> int { f!(b)}",
vec!(vec!(1)), false),
// the marks going in and out of letty should cancel, allowing that $x to
// capture the one following the semicolon.
// this was an awesome test case, and caught a *lot* of bugs.
("macro_rules! letty(($x:ident) => (let $x = 15;))
macro_rules! user(($x:ident) => ({letty!($x); $x}))
fn main() -> int {user!(z)}",
vec!(vec!(0)), false)
);
for (idx,s) in tests.iter().enumerate() {
run_renaming_test(s,idx);
}
}
// no longer a fixme #8062: this test exposes a *potential* bug; our system does
// not behave exactly like MTWT, but a conversation with Matthew Flatt
// suggests that this can only occur in the presence of local-expand, which
// we have no plans to support. ... unless it's needed for item hygiene....
#[ignore]
#[test] fn issue_8062(){
run_renaming_test(
&("fn main() {let hrcoo = 19; macro_rules! getx(()=>(hrcoo)); getx!();}",
vec!(vec!(0)), true), 0)
}
// FIXME #6994:
// the z flows into and out of two macros (g & f) along one path, and one
// (just g) along the other, so the result of the whole thing should
// be "let z_123 = 3; z_123"
#[ignore]
#[test] fn issue_6994(){
run_renaming_test(
&("macro_rules! g (($x:ident) =>
({macro_rules! f(($y:ident)=>({let $y=3;$x}));f!($x)}))
fn a(){g!(z)}",
vec!(vec!(0)),false),
0)
}
// match variable hygiene. Should expand into
// fn z() {match 8 {x_1 => {match 9 {x_2 | x_2 if x_2 == x_1 => x_2 + x_1}}}}
#[test] fn issue_9384(){
run_renaming_test(
&("macro_rules! bad_macro (($ex:expr) => ({match 9 {x | x if x == $ex => x + $ex}}))
fn z() {match 8 {x => bad_macro!(x)}}",
// NB: the third "binding" is the repeat of the second one.
vec!(vec!(1,3),vec!(0,2),vec!(0,2)),
true),
0)
}
// interpolated nodes weren't getting labeled.
// should expand into
// fn main(){let g1_1 = 13; g1_1}}
#[test] fn pat_expand_issue_15221(){
run_renaming_test(
&("macro_rules! inner ( ($e:pat ) => ($e))
macro_rules! outer ( ($e:pat ) => (inner!($e)))
fn main() { let outer!(g) = 13; g;}",
vec!(vec!(0)),
true),
0)
}
// create a really evil test case where a $x appears inside a binding of $x
// but *shouldn't* bind because it was inserted by a different macro....
// can't write this test case until we have macro-generating macros.
// method arg hygiene
// method expands to fn get_x(&self_0, x_1:int) {self_0 + self_2 + x_3 + x_1}
#[test] fn method_arg_hygiene(){
run_renaming_test(
&("macro_rules! inject_x (()=>(x))
macro_rules! inject_self (()=>(self))
struct A;
impl A{fn get_x(&self, x: int) {self + inject_self!() + inject_x!() + x;} }",
vec!(vec!(0),vec!(3)),
true),
0)
}
// ooh, got another bite?
// expands to struct A; impl A {fn thingy(&self_1) {self_1;}}
#[test] fn method_arg_hygiene_2(){
run_renaming_test(
&("struct A;
macro_rules! add_method (($T:ty) =>
(impl $T { fn thingy(&self) {self;} }))
add_method!(A)",
vec!(vec!(0)),
true),
0)
}
// item fn hygiene
// expands to fn q(x_1:int){fn g(x_2:int){x_2 + x_1};}
#[test] fn issue_9383(){
run_renaming_test(
&("macro_rules! bad_macro (($ex:expr) => (fn g(x:int){ x + $ex }))
fn q(x:int) { bad_macro!(x); }",
vec!(vec!(1),vec!(0)),true),
0)
}
// closure arg hygiene (ExprFnBlock)
// expands to fn f(){(|x_1 : int| {(x_2 + x_1)})(3);}
#[test] fn closure_arg_hygiene(){
run_renaming_test(
&("macro_rules! inject_x (()=>(x))
fn f(){(|x : int| {(inject_x!() + x)})(3);}",
vec!(vec!(1)),
true),
0)
}
// closure arg hygiene (ExprProc)
// expands to fn f(){(proc(x_1 : int) {(x_2 + x_1)})(3);}
#[test] fn closure_arg_hygiene_2(){
run_renaming_test(
&("macro_rules! inject_x (()=>(x))
fn f(){ (proc(x : int){(inject_x!() + x)})(3); }",
vec!(vec!(1)),
true),
0)
}
// macro_rules in method position. Sadly, unimplemented.
#[test] fn macro_in_method_posn(){
expand_crate_str(
"macro_rules! my_method (() => (fn thirteen(&self) -> int {13}))
struct A;
impl A{ my_method!()}
fn f(){A.thirteen;}".to_string());
}
// another nested macro
// expands to impl Entries {fn size_hint(&self_1) {self_1;}
#[test] fn item_macro_workaround(){
run_renaming_test(
&("macro_rules! item { ($i:item) => {$i}}
struct Entries;
macro_rules! iterator_impl {
() => { item!( impl Entries { fn size_hint(&self) { self;}})}}
iterator_impl! { }",
vec!(vec!(0)), true),
0)
}
// run one of the renaming tests
fn run_renaming_test(t: &RenamingTest, test_idx: uint) {
let invalid_name = token::special_idents::invalid.name;
let (teststr, bound_connections, bound_ident_check) = match *t {
(ref str,ref conns, bic) => (str.to_string(), conns.clone(), bic)
};
let cr = expand_crate_str(teststr.to_string());
let bindings = crate_bindings(&cr);
let varrefs = crate_varrefs(&cr);
// must be one check clause for each binding:
assert_eq!(bindings.len(),bound_connections.len());
for (binding_idx,shouldmatch) in bound_connections.iter().enumerate() {
let binding_name = mtwt::resolve(*bindings.get(binding_idx));
let binding_marks = mtwt::marksof(bindings.get(binding_idx).ctxt, invalid_name);
// shouldmatch can't name varrefs that don't exist:
assert!((shouldmatch.len() == 0) ||
(varrefs.len() > *shouldmatch.iter().max().unwrap()));
for (idx,varref) in varrefs.iter().enumerate() {
let print_hygiene_debug_info = || {
// good lord, you can't make a path with 0 segments, can you?
let final_varref_ident = match varref.segments.last() {
Some(pathsegment) => pathsegment.identifier,
None => fail!("varref with 0 path segments?")
};
let varref_name = mtwt::resolve(final_varref_ident);
let varref_idents : Vec<ast::Ident>
= varref.segments.iter().map(|s| s.identifier)
.collect();
println!("varref #{}: {}, resolves to {}",idx, varref_idents, varref_name);
let string = token::get_ident(final_varref_ident);
println!("varref's first segment's string: \"{}\"", string.get());
println!("binding #{}: {}, resolves to {}",
binding_idx, *bindings.get(binding_idx), binding_name);
mtwt::with_sctable(|x| mtwt::display_sctable(x));
};
if shouldmatch.contains(&idx) {
// it should be a path of length 1, and it should
// be free-identifier=? or bound-identifier=? to the given binding
assert_eq!(varref.segments.len(),1);
let varref_name = mtwt::resolve(varref.segments.get(0).identifier);
let varref_marks = mtwt::marksof(varref.segments
.get(0)
.identifier
.ctxt,
invalid_name);
if !(varref_name==binding_name) {
println!("uh oh, should match but doesn't:");
print_hygiene_debug_info();
}
assert_eq!(varref_name,binding_name);
if bound_ident_check {
// we're checking bound-identifier=?, and the marks
// should be the same, too:
assert_eq!(varref_marks,binding_marks.clone());
}
} else {
let varref_name = mtwt::resolve(varref.segments.get(0).identifier);
let fail = (varref.segments.len() == 1)
&& (varref_name == binding_name);
// temp debugging:
if fail {
println!("failure on test {}",test_idx);
println!("text of test case: \"{}\"", teststr);
println!("");
println!("uh oh, matches but shouldn't:");
print_hygiene_debug_info();
}
assert!(!fail);
}
}
}
}
#[test] fn fmt_in_macro_used_inside_module_macro() {
let crate_str = "macro_rules! fmt_wrap(($b:expr)=>($b.to_string()))
macro_rules! foo_module (() => (mod generated { fn a() { let xx = 147; fmt_wrap!(xx);}}))
foo_module!()
".to_string();
let cr = expand_crate_str(crate_str);
// find the xx binding
let bindings = crate_bindings(&cr);
let cxbinds: Vec<&ast::Ident> =
bindings.iter().filter(|b| {
let ident = token::get_ident(**b);
let string = ident.get();
"xx" == string
}).collect();
let cxbinds: &[&ast::Ident] = cxbinds.as_slice();
let cxbind = match cxbinds {
[b] => b,
_ => fail!("expected just one binding for ext_cx")
};
let resolved_binding = mtwt::resolve(*cxbind);
let varrefs = crate_varrefs(&cr);
// the xx binding should bind all of the xx varrefs:
for (idx,v) in varrefs.iter().filter(|p| {
p.segments.len() == 1
&& "xx" == token::get_ident(p.segments.get(0).identifier).get()
}).enumerate() {
if mtwt::resolve(v.segments.get(0).identifier) != resolved_binding {
println!("uh oh, xx binding didn't match xx varref:");
println!("this is xx varref \\# {}", idx);
println!("binding: {}", cxbind);
println!("resolves to: {}", resolved_binding);
println!("varref: {}", v.segments.get(0).identifier);
println!("resolves to: {}",
mtwt::resolve(v.segments.get(0).identifier));
mtwt::with_sctable(|x| mtwt::display_sctable(x));
}
assert_eq!(mtwt::resolve(v.segments.get(0).identifier),
resolved_binding);
};
}
#[test]
fn pat_idents(){
let pat = string_to_pat(
"(a,Foo{x:c @ (b,9),y:Bar(4,d)})".to_string());
let idents = pattern_bindings(&*pat);
assert_eq!(idents, strs_to_idents(vec!("a","c","b","d")));
}
// test the list of identifier patterns gathered by the visitor. Note that
// 'None' is listed as an identifier pattern because we don't yet know that
// it's the name of a 0-ary variant, and that 'i' appears twice in succession.
#[test]
fn crate_bindings_test(){
let the_crate = string_to_crate("fn main (a : int) -> int {|b| {
match 34 {None => 3, Some(i) | i => j, Foo{k:z,l:y} => \"banana\"}} }".to_string());
let idents = crate_bindings(&the_crate);
assert_eq!(idents, strs_to_idents(vec!("a","b","None","i","i","z","y")));
}
// test the IdentRenamer directly
#[test]
fn ident_renamer_test () {
let the_crate = string_to_crate("fn f(x : int){let x = x; x}".to_string());
let f_ident = token::str_to_ident("f");
let x_ident = token::str_to_ident("x");
let int_ident = token::str_to_ident("int");
let renames = vec!((x_ident,Name(16)));
let mut renamer = IdentRenamer{renames: &renames};
let renamed_crate = renamer.fold_crate(the_crate);
let idents = crate_idents(&renamed_crate);
let resolved : Vec<ast::Name> = idents.iter().map(|id| mtwt::resolve(*id)).collect();
assert_eq!(resolved,vec!(f_ident.name,Name(16),int_ident.name,Name(16),Name(16),Name(16)));
}
// test the PatIdentRenamer; only PatIdents get renamed
#[test]
fn pat_ident_renamer_test () {
let the_crate = string_to_crate("fn f(x : int){let x = x; x}".to_string());
let f_ident = token::str_to_ident("f");
let x_ident = token::str_to_ident("x");
let int_ident = token::str_to_ident("int");
let renames = vec!((x_ident,Name(16)));
let mut renamer = PatIdentRenamer{renames: &renames};
let renamed_crate = renamer.fold_crate(the_crate);
let idents = crate_idents(&renamed_crate);
let resolved : Vec<ast::Name> = idents.iter().map(|id| mtwt::resolve(*id)).collect();
let x_name = x_ident.name;
assert_eq!(resolved,vec!(f_ident.name,Name(16),int_ident.name,Name(16),x_name,x_name));
}
}
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