rollup merge of #24487: erickt/syntax

This removes the usage of `#[feature(into_cow, slice_patterns, box_syntax, box_patterns, quote, unsafe_destructor)]` from being used in libsyntax. My main desire for this is that it brings me one step closer to letting [syntex](https://github.com/erickt/rust-syntex) compile with stable rust. Hopefully this doesn't inconvenience rust development.

1 files changed, 57 insertions, 14 deletions

diff --git a/src/libsyntax/diagnostics/plugin.rs b/src/libsyntax/diagnostics/plugin.rs
index 6fcf39f0b17..6de4edafa0b 100644
--- a/src/libsyntax/diagnostics/plugin.rs
+++ b/src/libsyntax/diagnostics/plugin.rs
@@ -54,8 +54,8 @@ pub fn expand_diagnostic_used<'cx>(ecx: &'cx mut ExtCtxt,
                                    span: Span,
                                    token_tree: &[TokenTree])
                                    -> Box<MacResult+'cx> {
-    let code = match token_tree {
-        [ast::TtToken(_, token::Ident(code, _))] => code,
+    let code = match (token_tree.len(), token_tree.get(0)) {
+        (1, Some(&ast::TtToken(_, token::Ident(code, _)))) => code,
         _ => unreachable!()
     };
     with_used_diagnostics(|diagnostics| {
@@ -77,20 +77,25 @@ pub fn expand_diagnostic_used<'cx>(ecx: &'cx mut ExtCtxt,
             ));
         }
     });
-    MacEager::expr(quote_expr!(ecx, ()))
+    MacEager::expr(ecx.expr_tuple(span, Vec::new()))
 }
 
 pub fn expand_register_diagnostic<'cx>(ecx: &'cx mut ExtCtxt,
                                        span: Span,
                                        token_tree: &[TokenTree])
                                        -> Box<MacResult+'cx> {
-    let (code, description) = match token_tree {
-        [ast::TtToken(_, token::Ident(ref code, _))] => {
+    let (code, description) = match (
+        token_tree.len(),
+        token_tree.get(0),
+        token_tree.get(1),
+        token_tree.get(2)
+    ) {
+        (1, Some(&ast::TtToken(_, token::Ident(ref code, _))), None, None) => {
             (code, None)
         },
-        [ast::TtToken(_, token::Ident(ref code, _)),
-         ast::TtToken(_, token::Comma),
-         ast::TtToken(_, token::Literal(token::StrRaw(description, _), None))] => {
+        (3, Some(&ast::TtToken(_, token::Ident(ref code, _))),
+            Some(&ast::TtToken(_, token::Comma)),
+            Some(&ast::TtToken(_, token::Literal(token::StrRaw(description, _), None)))) => {
             (code, Some(description))
         }
         _ => unreachable!()
@@ -123,15 +128,23 @@ pub fn expand_register_diagnostic<'cx>(ecx: &'cx mut ExtCtxt,
     let sym = Ident::new(token::gensym(&(
         "__register_diagnostic_".to_string() + &token::get_ident(*code)
     )));
-    MacEager::items(SmallVector::many(vec![quote_item!(ecx, mod $sym {}).unwrap()]))
+    MacEager::items(SmallVector::many(vec![
+        ecx.item_mod(
+            span,
+            span,
+            sym,
+            Vec::new(),
+            Vec::new()
+        )
+    ]))
 }
 
 pub fn expand_build_diagnostic_array<'cx>(ecx: &'cx mut ExtCtxt,
                                           span: Span,
                                           token_tree: &[TokenTree])
                                           -> Box<MacResult+'cx> {
-    let name = match token_tree {
-        [ast::TtToken(_, token::Ident(ref name, _))] => name,
+    let name = match (token_tree.len(), token_tree.get(0)) {
+        (1, Some(&ast::TtToken(_, token::Ident(ref name, _)))) => name,
         _ => unreachable!()
     };
 
@@ -148,7 +161,37 @@ pub fn expand_build_diagnostic_array<'cx>(ecx: &'cx mut ExtCtxt,
             (descriptions.len(), ecx.expr_vec(span, descriptions))
         });
 
-    MacEager::items(SmallVector::many(vec![quote_item!(ecx,
-        pub static $name: [(&'static str, &'static str); $count] = $expr;
-    ).unwrap()]))
+    let static_ = ecx.lifetime(span, ecx.name_of("'static"));
+    let ty_str = ecx.ty_rptr(
+        span,
+        ecx.ty_ident(span, ecx.ident_of("str")),
+        Some(static_),
+        ast::MutImmutable,
+    );
+
+    let ty = ecx.ty(
+        span,
+        ast::TyFixedLengthVec(
+            ecx.ty(
+                span,
+                ast::TyTup(vec![ty_str.clone(), ty_str])
+            ),
+            ecx.expr_usize(span, count),
+        ),
+    );
+
+    MacEager::items(SmallVector::many(vec![
+        P(ast::Item {
+            ident: name.clone(),
+            attrs: Vec::new(),
+            id: ast::DUMMY_NODE_ID,
+            node: ast::ItemStatic(
+                ty,
+                ast::MutImmutable,
+                expr,
+            ),
+            vis: ast::Public,
+            span: span,
+        })
+    ]))
 }