Auto merge of #28552 - apasel422:issue-28527, r=Manishearth

Closes #28527.

r? @Manishearth 

7 files changed, 114 insertions, 139 deletions

diff --git a/src/libsyntax/ast.rs b/src/libsyntax/ast.rs
index 58d92f5001a..7b2b2c90126 100644
--- a/src/libsyntax/ast.rs
+++ b/src/libsyntax/ast.rs
@@ -28,7 +28,6 @@ pub use self::Item_::*;
 pub use self::KleeneOp::*;
 pub use self::Lit_::*;
 pub use self::LitIntType::*;
-pub use self::Mac_::*;
 pub use self::MacStmtStyle::*;
 pub use self::MetaItem_::*;
 pub use self::Mutability::*;
@@ -1132,12 +1131,13 @@ pub type Mac = Spanned<Mac_>;
 /// is being invoked, and the vector of token-trees contains the source
 /// of the macro invocation.
 ///
-/// There's only one flavor, now, so this could presumably be simplified.
+/// NB: the additional ident for a macro_rules-style macro is actually
+/// stored in the enclosing item. Oog.
 #[derive(Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Debug)]
-pub enum Mac_ {
-    // NB: the additional ident for a macro_rules-style macro is actually
-    // stored in the enclosing item. Oog.
-    MacInvocTT(Path, Vec<TokenTree>, SyntaxContext),   // new macro-invocation
+pub struct Mac_ {
+    pub path: Path,
+    pub tts: Vec<TokenTree>,
+    pub ctxt: SyntaxContext,
 }
 
 #[derive(Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Debug, Copy)]
diff --git a/src/libsyntax/ext/expand.rs b/src/libsyntax/ext/expand.rs
index ffbb7edd385..6e0fbbec770 100644
--- a/src/libsyntax/ext/expand.rs
+++ b/src/libsyntax/ext/expand.rs
@@ -9,7 +9,7 @@
 // except according to those terms.
 
 use ast::{Block, Crate, DeclLocal, ExprMac, PatMac};
-use ast::{Local, Ident, MacInvocTT};
+use ast::{Local, Ident, Mac_};
 use ast::{ItemMac, MacStmtWithSemicolon, Mrk, Stmt, StmtDecl, StmtMac};
 use ast::{StmtExpr, StmtSemi};
 use ast::TokenTree;
@@ -509,78 +509,75 @@ fn expand_mac_invoc<T, F, G>(mac: ast::Mac,
     F: for<'a> FnOnce(Box<MacResult+'a>) -> Option<T>,
     G: FnOnce(T, Mrk) -> 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() > 1 {
-                fld.cx.span_err(pth.span,
-                                "expected macro name without module \
-                                separators");
-                // let compilation continue
-                return None;
-            }
-            let extname = pth.segments[0].identifier.name;
-            match fld.cx.syntax_env.find(&extname) {
-                None => {
-                    fld.cx.span_err(
-                        pth.span,
-                        &format!("macro undefined: '{}!'",
-                                &extname));
+    // 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.
+
+    let Mac_ { path: pth, tts, .. } = mac.node;
+    if pth.segments.len() > 1 {
+        fld.cx.span_err(pth.span,
+                        "expected macro name without module \
+                        separators");
+        // let compilation continue
+        return None;
+    }
+    let extname = pth.segments[0].identifier.name;
+    match fld.cx.syntax_env.find(&extname) {
+        None => {
+            fld.cx.span_err(
+                pth.span,
+                &format!("macro undefined: '{}!'",
+                        &extname));
 
-                    // let compilation continue
-                    None
-                }
-                Some(rc) => match *rc {
-                    NormalTT(ref expandfun, exp_span, allow_internal_unstable) => {
-                        fld.cx.bt_push(ExpnInfo {
-                                call_site: span,
-                                callee: NameAndSpan {
-                                    format: MacroBang(extname),
-                                    span: exp_span,
-                                    allow_internal_unstable: allow_internal_unstable,
-                                },
-                            });
-                        let fm = fresh_mark();
-                        let marked_before = mark_tts(&tts[..], 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[..]);
-                            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: {}",
-                                            extname
-                                            ));
-                                return None;
-                            }
-                        };
-                        Some(mark_thunk(parsed,fm))
-                    }
-                    _ => {
+            // let compilation continue
+            None
+        }
+        Some(rc) => match *rc {
+            NormalTT(ref expandfun, exp_span, allow_internal_unstable) => {
+                fld.cx.bt_push(ExpnInfo {
+                        call_site: span,
+                        callee: NameAndSpan {
+                            format: MacroBang(extname),
+                            span: exp_span,
+                            allow_internal_unstable: allow_internal_unstable,
+                        },
+                    });
+                let fm = fresh_mark();
+                let marked_before = mark_tts(&tts[..], 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[..]);
+                    parse_thunk(expanded)
+                };
+                let parsed = match opt_parsed {
+                    Some(e) => e,
+                    None => {
                         fld.cx.span_err(
                             pth.span,
-                            &format!("'{}' is not a tt-style macro",
-                                    extname));
-                        None
+                            &format!("non-expression macro in expression position: {}",
+                                    extname
+                                    ));
+                        return None;
                     }
-                }
+                };
+                Some(mark_thunk(parsed,fm))
+            }
+            _ => {
+                fld.cx.span_err(
+                    pth.span,
+                    &format!("'{}' is not a tt-style macro",
+                            extname));
+                None
             }
         }
     }
@@ -684,15 +681,11 @@ fn contains_macro_use(fld: &mut MacroExpander, attrs: &[ast::Attribute]) -> bool
 // 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, span, attrs, ident) = it.and_then(|it| { match it.node {
-        ItemMac(codemap::Spanned {
-            node: MacInvocTT(pth, tts, _),
-            ..
-        }) => {
-            (pth.segments[0].identifier.name, pth.span, tts, it.span, it.attrs, it.ident)
-        }
+    let (extname, path_span, tts, span, attrs, ident) = it.and_then(|it| match it.node {
+        ItemMac(codemap::Spanned { node: Mac_ { path, tts, .. }, .. }) =>
+            (path.segments[0].identifier.name, path.span, tts, it.span, it.attrs, it.ident),
         _ => fld.cx.span_bug(it.span, "invalid item macro invocation")
-    }});
+    });
 
     let fm = fresh_mark();
     let items = {
@@ -1060,11 +1053,7 @@ fn expand_pat(p: P<ast::Pat>, fld: &mut MacroExpander) -> P<ast::Pat> {
     }
     p.map(|ast::Pat {node, span, ..}| {
         let (pth, tts) = match node {
-            PatMac(mac) => match mac.node {
-                MacInvocTT(pth, tts, _) => {
-                    (pth, tts)
-                }
-            },
+            PatMac(mac) => (mac.node.path, mac.node.tts),
             _ => unreachable!()
         };
         if pth.segments.len() > 1 {
@@ -1646,12 +1635,10 @@ impl Folder for Marker {
     }
     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[..]),
-                               mtwt::apply_mark(self.mark, ctxt))
-                }
+            node: Mac_ {
+                path: self.fold_path(node.path),
+                tts: self.fold_tts(&node.tts),
+                ctxt: mtwt::apply_mark(self.mark, node.ctxt),
             },
             span: span,
         }
diff --git a/src/libsyntax/feature_gate.rs b/src/libsyntax/feature_gate.rs
index 16d44e5046c..be95b58bf88 100644
--- a/src/libsyntax/feature_gate.rs
+++ b/src/libsyntax/feature_gate.rs
@@ -666,7 +666,7 @@ struct MacroVisitor<'a> {
 
 impl<'a, 'v> Visitor<'v> for MacroVisitor<'a> {
     fn visit_mac(&mut self, mac: &ast::Mac) {
-        let ast::MacInvocTT(ref path, _, _) = mac.node;
+        let path = &mac.node.path;
         let id = path.segments.last().unwrap().identifier;
 
         // Issue 22234: If you add a new case here, make sure to also
diff --git a/src/libsyntax/fold.rs b/src/libsyntax/fold.rs
index a73cc420eeb..e97c763ca4c 100644
--- a/src/libsyntax/fold.rs
+++ b/src/libsyntax/fold.rs
@@ -567,10 +567,10 @@ pub fn noop_fold_explicit_self<T: Folder>(Spanned {span, node}: ExplicitSelf, fl
 
 pub fn noop_fold_mac<T: Folder>(Spanned {node, span}: Mac, fld: &mut T) -> Mac {
     Spanned {
-        node: match node {
-            MacInvocTT(p, tts, ctxt) => {
-                MacInvocTT(fld.fold_path(p), fld.fold_tts(&tts), ctxt)
-            }
+        node: Mac_ {
+            path: fld.fold_path(node.path),
+            tts: fld.fold_tts(&node.tts),
+            ctxt: node.ctxt,
         },
         span: fld.new_span(span)
     }
diff --git a/src/libsyntax/parse/mod.rs b/src/libsyntax/parse/mod.rs
index 269f8bdd98a..279c987fcba 100644
--- a/src/libsyntax/parse/mod.rs
+++ b/src/libsyntax/parse/mod.rs
@@ -1090,10 +1090,7 @@ mod tests {
             "foo!( fn main() { body } )".to_string(), vec![], &sess);
 
         let tts = match expr.node {
-            ast::ExprMac(ref mac) => {
-                let ast::MacInvocTT(_, ref tts, _) = mac.node;
-                tts.clone()
-            }
+            ast::ExprMac(ref mac) => mac.node.tts.clone(),
             _ => panic!("not a macro"),
         };
 
diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index 581c28a44fd..6220bd6fa6f 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -37,7 +37,7 @@ use ast::{LifetimeDef, Lit, Lit_};
 use ast::{LitBool, LitChar, LitByte, LitByteStr};
 use ast::{LitStr, LitInt, Local};
 use ast::{MacStmtWithBraces, MacStmtWithSemicolon, MacStmtWithoutBraces};
-use ast::{MutImmutable, MutMutable, Mac_, MacInvocTT, MatchSource};
+use ast::{MutImmutable, MutMutable, Mac_, MatchSource};
 use ast::{MutTy, BiMul, Mutability};
 use ast::{MethodImplItem, NamedField, UnNeg, NoReturn, UnNot};
 use ast::{Pat, PatBox, PatEnum, PatIdent, PatLit, PatQPath, PatMac, PatRange};
@@ -1381,7 +1381,7 @@ impl<'a> Parser<'a> {
                                                      seq_sep_none(),
                                                      |p| p.parse_token_tree()));
                 let hi = self.span.hi;
-                TyMac(spanned(lo, hi, MacInvocTT(path, tts, EMPTY_CTXT)))
+                TyMac(spanned(lo, hi, Mac_ { path: path, tts: tts, ctxt: EMPTY_CTXT }))
             } else {
                 // NAMED TYPE
                 TyPath(None, path)
@@ -2203,9 +2203,7 @@ impl<'a> Parser<'a> {
 
                         return Ok(self.mk_mac_expr(lo,
                                                    hi,
-                                                   MacInvocTT(pth,
-                                                              tts,
-                                                              EMPTY_CTXT)));
+                                                   Mac_ { path: pth, tts: tts, ctxt: EMPTY_CTXT }));
                     }
                     if self.check(&token::OpenDelim(token::Brace)) {
                         // This is a struct literal, unless we're prohibited
@@ -3289,7 +3287,7 @@ impl<'a> Parser<'a> {
                         let delim = try!(self.expect_open_delim());
                         let tts = try!(self.parse_seq_to_end(&token::CloseDelim(delim),
                                 seq_sep_none(), |p| p.parse_token_tree()));
-                        let mac = MacInvocTT(path, tts, EMPTY_CTXT);
+                        let mac = Mac_ { path: path, tts: tts, ctxt: EMPTY_CTXT };
                         pat = PatMac(codemap::Spanned {node: mac, span: self.span});
                     } else {
                         // Parse ident @ pat
@@ -3557,7 +3555,7 @@ impl<'a> Parser<'a> {
                 spanned(lo, hi,
                         StmtMac(P(spanned(lo,
                                           hi,
-                                          MacInvocTT(pth, tts, EMPTY_CTXT))),
+                                          Mac_ { path: pth, tts: tts, ctxt: EMPTY_CTXT })),
                                   style))
             } else {
                 // if it has a special ident, it's definitely an item
@@ -3576,7 +3574,8 @@ impl<'a> Parser<'a> {
                     P(spanned(lo, hi, DeclItem(
                         self.mk_item(
                             lo, hi, id /*id is good here*/,
-                            ItemMac(spanned(lo, hi, MacInvocTT(pth, tts, EMPTY_CTXT))),
+                            ItemMac(spanned(lo, hi,
+                                            Mac_ { path: pth, tts: tts, ctxt: EMPTY_CTXT })),
                             Inherited, Vec::new(/*no attrs*/))))),
                     ast::DUMMY_NODE_ID))
             }
@@ -4524,7 +4523,7 @@ impl<'a> Parser<'a> {
             let tts = try!(self.parse_seq_to_end(&token::CloseDelim(delim),
                                             seq_sep_none(),
                                             |p| p.parse_token_tree()));
-            let m_ = ast::MacInvocTT(pth, tts, EMPTY_CTXT);
+            let m_ = Mac_ { path: pth, tts: tts, ctxt: EMPTY_CTXT };
             let m: ast::Mac = codemap::Spanned { node: m_,
                                                 span: mk_sp(self.span.lo,
                                                             self.span.hi) };
@@ -5606,7 +5605,7 @@ impl<'a> Parser<'a> {
                                             seq_sep_none(),
                                             |p| p.parse_token_tree()));
             // single-variant-enum... :
-            let m = ast::MacInvocTT(pth, tts, EMPTY_CTXT);
+            let m = Mac_ { path: pth, tts: tts, ctxt: EMPTY_CTXT };
             let m: ast::Mac = codemap::Spanned { node: m,
                                              span: mk_sp(self.span.lo,
                                                          self.span.hi) };
diff --git a/src/libsyntax/print/pprust.rs b/src/libsyntax/print/pprust.rs
index 6de6d32dfb3..915abd4c0eb 100644
--- a/src/libsyntax/print/pprust.rs
+++ b/src/libsyntax/print/pprust.rs
@@ -1307,16 +1307,14 @@ impl<'a> State<'a> {
                 }
                 try!(self.bclose(item.span));
             }
-            // I think it's reasonable to hide the context here:
-            ast::ItemMac(codemap::Spanned { node: ast::MacInvocTT(ref pth, ref tts, _),
-                                            ..}) => {
+            ast::ItemMac(codemap::Spanned { ref node, .. }) => {
                 try!(self.print_visibility(item.vis));
-                try!(self.print_path(pth, false, 0));
+                try!(self.print_path(&node.path, false, 0));
                 try!(word(&mut self.s, "! "));
                 try!(self.print_ident(item.ident));
                 try!(self.cbox(indent_unit));
                 try!(self.popen());
-                try!(self.print_tts(&tts[..]));
+                try!(self.print_tts(&node.tts[..]));
                 try!(self.pclose());
                 try!(word(&mut self.s, ";"));
                 try!(self.end());
@@ -1599,14 +1597,13 @@ impl<'a> State<'a> {
             ast::TypeImplItem(ref ty) => {
                 try!(self.print_associated_type(ii.ident, None, Some(ty)));
             }
-            ast::MacImplItem(codemap::Spanned { node: ast::MacInvocTT(ref pth, ref tts, _),
-                                                ..}) => {
+            ast::MacImplItem(codemap::Spanned { ref node, .. }) => {
                 // code copied from ItemMac:
-                try!(self.print_path(pth, false, 0));
+                try!(self.print_path(&node.path, false, 0));
                 try!(word(&mut self.s, "! "));
                 try!(self.cbox(indent_unit));
                 try!(self.popen());
-                try!(self.print_tts(&tts[..]));
+                try!(self.print_tts(&node.tts[..]));
                 try!(self.pclose());
                 try!(word(&mut self.s, ";"));
                 try!(self.end())
@@ -1765,23 +1762,18 @@ impl<'a> State<'a> {
 
     pub fn print_mac(&mut self, m: &ast::Mac, delim: token::DelimToken)
                      -> io::Result<()> {
-        match m.node {
-            // I think it's reasonable to hide the ctxt here:
-            ast::MacInvocTT(ref pth, ref tts, _) => {
-                try!(self.print_path(pth, false, 0));
-                try!(word(&mut self.s, "!"));
-                match delim {
-                    token::Paren => try!(self.popen()),
-                    token::Bracket => try!(word(&mut self.s, "[")),
-                    token::Brace => try!(self.bopen()),
-                }
-                try!(self.print_tts(tts));
-                match delim {
-                    token::Paren => self.pclose(),
-                    token::Bracket => word(&mut self.s, "]"),
-                    token::Brace => self.bclose(m.span),
-                }
-            }
+        try!(self.print_path(&m.node.path, false, 0));
+        try!(word(&mut self.s, "!"));
+        match delim {
+            token::Paren => try!(self.popen()),
+            token::Bracket => try!(word(&mut self.s, "[")),
+            token::Brace => try!(self.bopen()),
+        }
+        try!(self.print_tts(&m.node.tts));
+        match delim {
+            token::Paren => self.pclose(),
+            token::Bracket => word(&mut self.s, "]"),
+            token::Brace => self.bclose(m.span),
         }
     }