Auto merge of #34424 - jseyfried:breaking_batch, r=<try>

Batch up libsyntax breaking changes

Batch of the following syntax-[breaking-change] changes:
 - #34213: Add a variant `Macro` to `TraitItemKind`
 - #34368: Merge the variant `QPath` of `PatKind` into the variant `PatKind::Path`
 - #34385: Move `syntax::ast::TokenTree` into a new module `syntax::tokenstream`
 - #33943:
  - Remove the type parameter from `visit::Visitor`
  - Remove `attr::WithAttrs` -- use `attr::HasAttrs` instead.
  - Change `fold_tt`/`fold_tts` to take token trees by value and avoid wrapping token trees in `Rc`.
  - Remove the field `ctxt` of `ast::Mac_`
  - Remove inherent method `attrs()` of types -- use the method `attrs` of `HasAttrs` instead.
 - #34316:
  - Remove `ast::Decl`/`ast::DeclKind` and add variants `Local` and `Item` to `StmtKind`.
  - Move the node id for statements from the `StmtKind` variants to a field of `Stmt` (making `Stmt` a struct instead of an alias for `Spanned<StmtKind>`)
  - Rename `ast::ExprKind::Again` to `Continue`.
 - #34339: Generalize and abstract `ThinAttributes` to `ThinVec<Attribute>`
  - Use `.into()` in convert between `Vec<Attribute>` and `ThinVec<Attribute>`
  - Use autoderef instead of `.as_attr_slice()`
 - #34436: Remove the optional expression from `ast::Block` and instead use a `StmtKind::Expr` at the end of the statement list.
 - #34403: Move errors into a separate crate (unlikely to cause breakage)

Author: bors

mk/crates.mk

@@ -57,10 +57,10 @@ TARGET_CRATES := libc std term \
 		 panic_abort panic_unwind unwind
 RUSTC_CRATES := rustc rustc_typeck rustc_mir rustc_borrowck rustc_resolve rustc_driver \
                 rustc_trans rustc_back rustc_llvm rustc_privacy rustc_lint \
-                rustc_data_structures rustc_platform_intrinsics \
+                rustc_data_structures rustc_platform_intrinsics rustc_errors \
                 rustc_plugin rustc_metadata rustc_passes rustc_save_analysis \
                 rustc_const_eval rustc_const_math rustc_incremental
-HOST_CRATES := syntax syntax_ext $(RUSTC_CRATES) rustdoc fmt_macros \
+HOST_CRATES := syntax syntax_ext syntax_pos $(RUSTC_CRATES) rustdoc fmt_macros \
 		flate arena graphviz rbml log serialize
 TOOLS := compiletest rustdoc rustc rustbook error_index_generator
 
@@ -98,43 +98,45 @@ DEPS_serialize := std log
 DEPS_term := std
 DEPS_test := std getopts term native:rust_test_helpers
 
-DEPS_syntax := std term serialize log arena libc rustc_bitflags rustc_unicode
-DEPS_syntax_ext := syntax fmt_macros
+DEPS_syntax := std term serialize log arena libc rustc_bitflags rustc_unicode rustc_errors syntax_pos
+DEPS_syntax_ext := syntax syntax_pos rustc_errors fmt_macros
+DEPS_syntax_pos := serialize
 
 DEPS_rustc_const_math := std syntax log serialize
 DEPS_rustc_const_eval := rustc_const_math rustc syntax log serialize \
-					     rustc_back graphviz
+			     rustc_back graphviz syntax_pos
 
 DEPS_rustc := syntax fmt_macros flate arena serialize getopts rbml \
               log graphviz rustc_llvm rustc_back rustc_data_structures\
-		  	  rustc_const_math
+	      rustc_const_math syntax_pos rustc_errors
 DEPS_rustc_back := std syntax flate log libc
-DEPS_rustc_borrowck := rustc log graphviz syntax rustc_mir
+DEPS_rustc_borrowck := rustc log graphviz syntax syntax_pos rustc_errors rustc_mir
 DEPS_rustc_data_structures := std log serialize
 DEPS_rustc_driver := arena flate getopts graphviz libc rustc rustc_back rustc_borrowck \
                      rustc_typeck rustc_mir rustc_resolve log syntax serialize rustc_llvm \
 	             rustc_trans rustc_privacy rustc_lint rustc_plugin \
                      rustc_metadata syntax_ext rustc_passes rustc_save_analysis rustc_const_eval \
-                     rustc_incremental
-DEPS_rustc_lint := rustc log syntax rustc_const_eval
+                     rustc_incremental syntax_pos rustc_errors
+DEPS_rustc_errors := log libc serialize syntax_pos
+DEPS_rustc_lint := rustc log syntax syntax_pos rustc_const_eval
 DEPS_rustc_llvm := native:rustllvm libc std rustc_bitflags
-DEPS_rustc_metadata := rustc syntax rbml rustc_const_math
-DEPS_rustc_passes := syntax rustc core rustc_const_eval
-DEPS_rustc_mir := rustc syntax rustc_const_math rustc_const_eval rustc_bitflags
-DEPS_rustc_resolve := arena rustc log syntax
+DEPS_rustc_metadata := rustc syntax syntax_pos rustc_errors rbml rustc_const_math
+DEPS_rustc_passes := syntax syntax_pos rustc core rustc_const_eval rustc_errors
+DEPS_rustc_mir := rustc syntax syntax_pos rustc_const_math rustc_const_eval rustc_bitflags
+DEPS_rustc_resolve := arena rustc log syntax syntax_pos rustc_errors
 DEPS_rustc_platform_intrinsics := std
-DEPS_rustc_plugin := rustc rustc_metadata syntax
-DEPS_rustc_privacy := rustc log syntax
+DEPS_rustc_plugin := rustc rustc_metadata syntax syntax_pos rustc_errors
+DEPS_rustc_privacy := rustc log syntax syntax_pos
 DEPS_rustc_trans := arena flate getopts graphviz libc rustc rustc_back \
                     log syntax serialize rustc_llvm rustc_platform_intrinsics \
-                    rustc_const_math rustc_const_eval rustc_incremental
-DEPS_rustc_incremental := rbml rustc serialize rustc_data_structures
-DEPS_rustc_save_analysis := rustc log syntax serialize
-DEPS_rustc_typeck := rustc syntax rustc_platform_intrinsics rustc_const_math \
-                     rustc_const_eval
+                    rustc_const_math rustc_const_eval rustc_incremental rustc_errors syntax_pos
+DEPS_rustc_incremental := rbml rustc syntax_pos serialize rustc_data_structures
+DEPS_rustc_save_analysis := rustc log syntax syntax_pos serialize
+DEPS_rustc_typeck := rustc syntax syntax_pos rustc_platform_intrinsics rustc_const_math \
+                     rustc_const_eval rustc_errors
 
 DEPS_rustdoc := rustc rustc_driver native:hoedown serialize getopts \
-                test rustc_lint rustc_const_eval
+                test rustc_lint rustc_const_eval syntax_pos
 
 
 TOOL_DEPS_compiletest := test getopts log serialize

src/doc/book/compiler-plugins.md

@@ -45,11 +45,11 @@ extern crate syntax;
 extern crate rustc;
 extern crate rustc_plugin;
 
-use syntax::codemap::Span;
 use syntax::parse::token;
 use syntax::ast::TokenTree;
 use syntax::ext::base::{ExtCtxt, MacResult, DummyResult, MacEager};
 use syntax::ext::build::AstBuilder;  // trait for expr_usize
+use syntax_pos::Span;
 use rustc_plugin::Registry;
 
 fn expand_rn(cx: &mut ExtCtxt, sp: Span, args: &[TokenTree])

src/grammar/verify.rs

@@ -32,9 +32,9 @@ use std::rc::Rc;
 use syntax::ast;
 use syntax::ast::Name;
 use syntax::codemap;
-use syntax::codemap::Pos;
 use syntax::parse::token::{self, BinOpToken, DelimToken, Lit, Token};
 use syntax::parse::lexer::TokenAndSpan;
+use syntax_pos::Pos;
 
 fn parse_token_list(file: &str) -> HashMap<String, token::Token> {
     fn id() -> token::Token {
@@ -233,10 +233,10 @@ fn parse_antlr_token(s: &str, tokens: &HashMap<String, token::Token>, surrogate_
     lo -= surrogate_pairs_pos.binary_search(&(lo as usize)).unwrap_or_else(|x| x) as u32;
     hi -= surrogate_pairs_pos.binary_search(&(hi as usize)).unwrap_or_else(|x| x) as u32;
 
-    let sp = codemap::Span {
-        lo: codemap::BytePos(lo),
-        hi: codemap::BytePos(hi),
-        expn_id: codemap::NO_EXPANSION
+    let sp = syntax_pos::Span {
+        lo: syntax_pos::BytePos(lo),
+        hi: syntax_pos::BytePos(hi),
+        expn_id: syntax_pos::NO_EXPANSION
     };
 
     TokenAndSpan {

src/librustc/Cargo.toml

@@ -19,6 +19,8 @@ rustc_back = { path = "../librustc_back" }
 rustc_bitflags = { path = "../librustc_bitflags" }
 rustc_const_math = { path = "../librustc_const_math" }
 rustc_data_structures = { path = "../librustc_data_structures" }
+rustc_errors = { path = "../librustc_errors" }
 rustc_llvm = { path = "../librustc_llvm" }
 serialize = { path = "../libserialize" }
 syntax = { path = "../libsyntax" }
+syntax_pos = { path "../libsyntax_pos" }

src/librustc/hir/check_attr.rs

@@ -95,7 +95,7 @@ impl<'a> CheckAttrVisitor<'a> {
     }
 }
 
-impl<'a, 'v> Visitor<'v> for CheckAttrVisitor<'a> {
+impl<'a> Visitor for CheckAttrVisitor<'a> {
     fn visit_item(&mut self, item: &ast::Item) {
         let target = Target::from_item(item);
         for attr in &item.attrs {

src/librustc/hir/fold.rs

@@ -14,9 +14,9 @@
 use hir::*;
 use syntax::ast::{Name, NodeId, DUMMY_NODE_ID, Attribute, Attribute_, MetaItem};
 use syntax::ast::MetaItemKind;
-use syntax::attr::ThinAttributesExt;
 use hir;
-use syntax::codemap::{respan, Span, Spanned};
+use syntax_pos::Span;
+use syntax::codemap::{respan, Spanned};
 use syntax::ptr::P;
 use syntax::parse::token::keywords;
 use syntax::util::move_map::MoveMap;
@@ -292,8 +292,11 @@ pub fn noop_fold_view_path<T: Folder>(view_path: P<ViewPath>, fld: &mut T) -> P<
     })
 }
 
-pub fn fold_attrs<T: Folder>(attrs: HirVec<Attribute>, fld: &mut T) -> HirVec<Attribute> {
-    attrs.move_flat_map(|x| fld.fold_attribute(x))
+pub fn fold_attrs<T, F>(attrs: T, fld: &mut F) -> T
+    where T: Into<Vec<Attribute>> + From<Vec<Attribute>>,
+          F: Folder,
+{
+    attrs.into().move_flat_map(|x| fld.fold_attribute(x)).into()
 }
 
 pub fn noop_fold_arm<T: Folder>(Arm { attrs, pats, guard, body }: Arm, fld: &mut T) -> Arm {
@@ -461,7 +464,7 @@ pub fn noop_fold_local<T: Folder>(l: P<Local>, fld: &mut T) -> P<Local> {
             pat: fld.fold_pat(pat),
             init: init.map(|e| fld.fold_expr(e)),
             span: fld.new_span(span),
-            attrs: attrs.map_thin_attrs(|attrs| fold_attrs(attrs.into(), fld).into()),
+            attrs: fold_attrs(attrs, fld),
         }
     })
 }
@@ -1078,7 +1081,7 @@ pub fn noop_fold_expr<T: Folder>(Expr { id, node, span, attrs }: Expr, folder: &
             }
         },
         span: folder.new_span(span),
-        attrs: attrs.map_thin_attrs(|attrs| fold_attrs(attrs.into(), folder).into()),
+        attrs: fold_attrs(attrs, folder),
     }
 }
 

src/librustc/hir/intravisit.rs

@@ -27,8 +27,8 @@
 
 use syntax::abi::Abi;
 use syntax::ast::{NodeId, CRATE_NODE_ID, Name, Attribute};
-use syntax::attr::ThinAttributesExt;
-use syntax::codemap::{Span, Spanned};
+use syntax::codemap::Spanned;
+use syntax_pos::Span;
 use hir::*;
 
 use std::cmp;
@@ -756,7 +756,7 @@ pub fn walk_expr<'v, V: Visitor<'v>>(visitor: &mut V, expression: &'v Expr) {
             walk_list!(visitor, visit_arm, arms);
         }
         ExprClosure(_, ref function_declaration, ref body, _fn_decl_span) => {
-            visitor.visit_fn(FnKind::Closure(expression.attrs.as_attr_slice()),
+            visitor.visit_fn(FnKind::Closure(&expression.attrs),
                              function_declaration,
                              body,
                              expression.span,