Rollup merge of rust-lang#34403 - jonathandturner:move_liberror, r=alexcrichton

This PR refactors the 'errors' part of libsyntax into its own crate (librustc_errors).  This is the first part of a few refactorings to simplify error reporting and potentially support more output formats (like a standardized JSON output and possibly an --explain mode that can work with the user's code), though this PR stands on its own and doesn't assume further changes.

As part of separating out the errors crate, I have also refactored the code position portion of codemap into its own crate (libsyntax_pos).  While it's helpful to have the common code positions in a separate crate for the new errors crate, this may also enable further simplifications in the future.

Author: jseyfried

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/fold.rs

@@ -16,7 +16,8 @@ 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;

src/librustc/hir/intravisit.rs

@@ -28,7 +28,8 @@
 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;

src/librustc/hir/lowering.rs

@@ -52,10 +52,11 @@ use std::iter;
 use syntax::ast::*;
 use syntax::attr::{ThinAttributes, ThinAttributesExt};
 use syntax::ptr::P;
-use syntax::codemap::{respan, Spanned, Span};
+use syntax::codemap::{respan, Spanned};
 use syntax::parse::token;
 use syntax::std_inject;
 use syntax::visit::{self, Visitor};
+use syntax_pos::Span;
 
 pub struct LoweringContext<'a> {
     crate_root: Option<&'static str>,

src/librustc/hir/map/blocks.rs

@@ -29,7 +29,7 @@ use hir::{Block, FnDecl};
 use syntax::ast::{Attribute, Name, NodeId};
 use syntax::attr::ThinAttributesExt;
 use hir as ast;
-use syntax::codemap::Span;
+use syntax_pos::Span;
 use hir::intravisit::FnKind;
 
 /// An FnLikeNode is a Node that is like a fn, in that it has a decl

src/librustc/hir/map/collector.rs

@@ -17,7 +17,7 @@ use hir::def_id::DefId;
 use middle::cstore::InlinedItem;
 use std::iter::repeat;
 use syntax::ast::{NodeId, CRATE_NODE_ID};
-use syntax::codemap::Span;
+use syntax_pos::Span;
 
 /// A Visitor that walks over the HIR and collects Nodes into a HIR map
 pub struct NodeCollector<'ast> {

src/librustc/hir/map/mod.rs

@@ -24,8 +24,9 @@ use hir::def_id::{CRATE_DEF_INDEX, DefId, DefIndex};
 use syntax::abi::Abi;
 use syntax::ast::{self, Name, NodeId, DUMMY_NODE_ID, };
 use syntax::attr::ThinAttributesExt;
-use syntax::codemap::{Span, Spanned};
+use syntax::codemap::Spanned;
 use syntax::visit;
+use syntax_pos::Span;
 
 use hir::*;
 use hir::fold::Folder;

src/librustc/hir/mod.rs

@@ -36,7 +36,8 @@ use hir::def::Def;
 use hir::def_id::DefId;
 use util::nodemap::{NodeMap, FnvHashSet};
 
-use syntax::codemap::{self, mk_sp, respan, Span, Spanned, ExpnId};
+use syntax_pos::{mk_sp, Span, ExpnId};
+use syntax::codemap::{self, respan, Spanned};
 use syntax::abi::Abi;
 use syntax::ast::{Name, NodeId, DUMMY_NODE_ID, TokenTree, AsmDialect};
 use syntax::ast::{Attribute, Lit, StrStyle, FloatTy, IntTy, UintTy, MetaItem};

src/librustc/hir/pat_util.rs

@@ -14,7 +14,8 @@ use hir::{self, PatKind};
 use ty::TyCtxt;
 use util::nodemap::FnvHashMap;
 use syntax::ast;
-use syntax::codemap::{Span, Spanned, DUMMY_SP};
+use syntax::codemap::Spanned;
+use syntax_pos::{Span, DUMMY_SP};
 
 use std::iter::{Enumerate, ExactSizeIterator};
 

src/librustc/hir/print.rs

@@ -12,15 +12,16 @@ pub use self::AnnNode::*;
 
 use syntax::abi::Abi;
 use syntax::ast;
-use syntax::codemap::{self, CodeMap, BytePos, Spanned};
-use syntax::errors;
+use syntax::codemap::{CodeMap, Spanned};
 use syntax::parse::token::{self, keywords, BinOpToken};
 use syntax::parse::lexer::comments;
 use syntax::print::pp::{self, break_offset, word, space, hardbreak};
 use syntax::print::pp::{Breaks, eof};
 use syntax::print::pp::Breaks::{Consistent, Inconsistent};
 use syntax::print::pprust::{self as ast_pp, PrintState};
 use syntax::ptr::P;
+use syntax_pos::{self, BytePos};
+use errors;
 
 use hir;
 use hir::{Crate, PatKind, RegionTyParamBound, SelfKind, TraitTyParamBound, TraitBoundModifier};
@@ -368,11 +369,11 @@ impl<'a> State<'a> {
         self.end() // close the head-box
     }
 
-    pub fn bclose_(&mut self, span: codemap::Span, indented: usize) -> io::Result<()> {
+    pub fn bclose_(&mut self, span: syntax_pos::Span, indented: usize) -> io::Result<()> {
         self.bclose_maybe_open(span, indented, true)
     }
     pub fn bclose_maybe_open(&mut self,
-                             span: codemap::Span,
+                             span: syntax_pos::Span,
                              indented: usize,
                              close_box: bool)
                              -> io::Result<()> {
@@ -384,7 +385,7 @@ impl<'a> State<'a> {
         }
         Ok(())
     }
-    pub fn bclose(&mut self, span: codemap::Span) -> io::Result<()> {
+    pub fn bclose(&mut self, span: syntax_pos::Span) -> io::Result<()> {
         self.bclose_(span, indent_unit)
     }
 
@@ -432,7 +433,7 @@ impl<'a> State<'a> {
                                   mut get_span: G)
                                   -> io::Result<()>
         where F: FnMut(&mut State, &T) -> io::Result<()>,
-              G: FnMut(&T) -> codemap::Span
+              G: FnMut(&T) -> syntax_pos::Span
     {
         self.rbox(0, b)?;
         let len = elts.len();
@@ -859,7 +860,7 @@ impl<'a> State<'a> {
                           enum_definition: &hir::EnumDef,
                           generics: &hir::Generics,
                           name: ast::Name,
-                          span: codemap::Span,
+                          span: syntax_pos::Span,
                           visibility: &hir::Visibility)
                           -> io::Result<()> {
         self.head(&visibility_qualified(visibility, "enum"))?;
@@ -872,7 +873,7 @@ impl<'a> State<'a> {
 
     pub fn print_variants(&mut self,
                           variants: &[hir::Variant],
-                          span: codemap::Span)
+                          span: syntax_pos::Span)
                           -> io::Result<()> {
         self.bopen()?;
         for v in variants {
@@ -902,7 +903,7 @@ impl<'a> State<'a> {
                         struct_def: &hir::VariantData,
                         generics: &hir::Generics,
                         name: ast::Name,
-                        span: codemap::Span,
+                        span: syntax_pos::Span,
                         print_finalizer: bool)
                         -> io::Result<()> {
         self.print_name(name)?;
@@ -2237,7 +2238,7 @@ impl<'a> State<'a> {
     }
 
     pub fn maybe_print_trailing_comment(&mut self,
-                                        span: codemap::Span,
+                                        span: syntax_pos::Span,
                                         next_pos: Option<BytePos>)
                                         -> io::Result<()> {
         let cm = match self.cm {

src/librustc/infer/combine.rs

@@ -49,7 +49,7 @@ use ty::relate::{RelateResult, TypeRelation};
 use traits::PredicateObligations;
 
 use syntax::ast;
-use syntax::codemap::Span;
+use syntax_pos::Span;
 
 #[derive(Clone)]
 pub struct CombineFields<'a, 'gcx: 'a+'tcx, 'tcx: 'a> {

src/librustc/infer/error_reporting.rs

@@ -91,10 +91,10 @@ use std::cell::{Cell, RefCell};
 use std::char::from_u32;
 use std::fmt;
 use syntax::ast;
-use syntax::errors::{DiagnosticBuilder, check_old_skool};
-use syntax::codemap::{self, Pos, Span};
 use syntax::parse::token;
 use syntax::ptr::P;
+use syntax_pos::{self, Pos, Span};
+use errors::{DiagnosticBuilder, check_old_skool};
 
 impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
     pub fn note_and_explain_region(self,
@@ -1933,6 +1933,6 @@ impl LifeGiver {
 
 fn name_to_dummy_lifetime(name: ast::Name) -> hir::Lifetime {
     hir::Lifetime { id: ast::DUMMY_NODE_ID,
-                    span: codemap::DUMMY_SP,
+                    span: syntax_pos::DUMMY_SP,
                     name: name }
 }

src/librustc/infer/higher_ranked/mod.rs

@@ -23,7 +23,7 @@ use super::region_inference::{TaintDirections};
 use ty::{self, TyCtxt, Binder, TypeFoldable};
 use ty::error::TypeError;
 use ty::relate::{Relate, RelateResult, TypeRelation};
-use syntax::codemap::Span;
+use syntax_pos::Span;
 use util::nodemap::{FnvHashMap, FnvHashSet};
 
 pub struct HrMatchResult<U> {

src/librustc/infer/mod.rs

@@ -39,9 +39,8 @@ use rustc_data_structures::unify::{self, UnificationTable};
 use std::cell::{Cell, RefCell, Ref, RefMut};
 use std::fmt;
 use syntax::ast;
-use syntax::codemap;
-use syntax::codemap::{Span, DUMMY_SP};
-use syntax::errors::DiagnosticBuilder;
+use errors::DiagnosticBuilder;
+use syntax_pos::{self, Span, DUMMY_SP};
 use util::nodemap::{FnvHashMap, FnvHashSet, NodeMap};
 
 use self::combine::CombineFields;
@@ -1036,7 +1035,7 @@ impl<'a, 'gcx, 'tcx> InferCtxt<'a, 'gcx, 'tcx> {
                          -> UnitResult<'tcx>
     {
         self.probe(|_| {
-            let origin = TypeOrigin::Misc(codemap::DUMMY_SP);
+            let origin = TypeOrigin::Misc(syntax_pos::DUMMY_SP);
             let trace = TypeTrace::types(origin, true, a, b);
             self.sub(true, trace, &a, &b).map(|_| ())
         })
@@ -1813,7 +1812,7 @@ impl<'a, 'gcx, 'tcx> TypeTrace<'tcx> {
 
     pub fn dummy(tcx: TyCtxt<'a, 'gcx, 'tcx>) -> TypeTrace<'tcx> {
         TypeTrace {
-            origin: TypeOrigin::Misc(codemap::DUMMY_SP),
+            origin: TypeOrigin::Misc(syntax_pos::DUMMY_SP),
             values: Types(ExpectedFound {
                 expected: tcx.types.err,
                 found: tcx.types.err,
@@ -1887,7 +1886,7 @@ impl RegionVariableOrigin {
             Coercion(a) => a,
             EarlyBoundRegion(a, _) => a,
             LateBoundRegion(a, _, _) => a,
-            BoundRegionInCoherence(_) => codemap::DUMMY_SP,
+            BoundRegionInCoherence(_) => syntax_pos::DUMMY_SP,
             UpvarRegion(_, a) => a
         }
     }

src/librustc/infer/type_variable.rs

@@ -13,7 +13,7 @@ use self::TypeVariableValue::*;
 use self::UndoEntry::*;
 use hir::def_id::{DefId};
 use ty::{self, Ty};
-use syntax::codemap::Span;
+use syntax_pos::Span;
 
 use std::cmp::min;
 use std::marker::PhantomData;

src/librustc/lib.rs

@@ -55,8 +55,10 @@ extern crate rustc_data_structures;
 extern crate serialize;
 extern crate collections;
 extern crate rustc_const_math;
+extern crate rustc_errors as errors;
 #[macro_use] extern crate log;
 #[macro_use] extern crate syntax;
+#[macro_use] extern crate syntax_pos;
 #[macro_use] #[no_link] extern crate rustc_bitflags;
 
 extern crate serialize as rustc_serialize; // used by deriving