Rollup merge of #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.

8 files changed, 22 insertions, 21 deletions

diff --git a/src/libsyntax/ext/base.rs b/src/libsyntax/ext/base.rs
index 9d467b4095a..3ee25634207 100644
--- a/src/libsyntax/ext/base.rs
+++ b/src/libsyntax/ext/base.rs
@@ -13,8 +13,8 @@ pub use self::SyntaxExtension::*;
 use ast;
 use ast::{Name, PatKind};
 use attr::HasAttrs;
-use codemap;
-use codemap::{CodeMap, Span, ExpnId, ExpnInfo, NO_EXPANSION};
+use codemap::{self, CodeMap, ExpnInfo};
+use syntax_pos::{Span, ExpnId, NO_EXPANSION};
 use errors::DiagnosticBuilder;
 use ext;
 use ext::expand;
diff --git a/src/libsyntax/ext/build.rs b/src/libsyntax/ext/build.rs
index 1d27cf5b0a1..fdf26263330 100644
--- a/src/libsyntax/ext/build.rs
+++ b/src/libsyntax/ext/build.rs
@@ -11,7 +11,8 @@
 use abi::Abi;
 use ast::{self, Ident, Generics, Expr, BlockCheckMode, UnOp, PatKind};
 use attr;
-use codemap::{Span, respan, Spanned, DUMMY_SP, Pos};
+use syntax_pos::{Span, DUMMY_SP, Pos};
+use codemap::{respan, Spanned};
 use ext::base::ExtCtxt;
 use parse::token::{self, keywords, InternedString};
 use ptr::P;
diff --git a/src/libsyntax/ext/expand.rs b/src/libsyntax/ext/expand.rs
index 126f39bcb0e..123d38c0006 100644
--- a/src/libsyntax/ext/expand.rs
+++ b/src/libsyntax/ext/expand.rs
@@ -18,8 +18,8 @@ use ext::mtwt;
 use ext::build::AstBuilder;
 use attr;
 use attr::{AttrMetaMethods, WithAttrs, ThinAttributesExt};
-use codemap;
-use codemap::{Span, Spanned, ExpnInfo, ExpnId, NameAndSpan, MacroBang, MacroAttribute};
+use codemap::{Spanned, ExpnInfo, NameAndSpan, MacroBang, MacroAttribute};
+use syntax_pos::{self, Span, ExpnId};
 use config::StripUnconfigured;
 use ext::base::*;
 use feature_gate::{self, Features};
@@ -1053,7 +1053,7 @@ impl<'a, 'b> Folder for MacroExpander<'a, 'b> {
                 result = expand_item(item, self);
                 self.pop_mod_path();
             } else {
-                let filename = if inner != codemap::DUMMY_SP {
+                let filename = if inner != syntax_pos::DUMMY_SP {
                     Some(self.cx.parse_sess.codemap().span_to_filename(inner))
                 } else { None };
                 let orig_filename = replace(&mut self.cx.filename, filename);
@@ -1242,7 +1242,7 @@ mod tests {
     use super::{PatIdentFinder, IdentRenamer, PatIdentRenamer, ExpansionConfig};
     use ast;
     use ast::Name;
-    use codemap;
+    use syntax_pos;
     use ext::base::{ExtCtxt, DummyMacroLoader};
     use ext::mtwt;
     use fold::Folder;
@@ -1284,7 +1284,7 @@ mod tests {
     }
 
     impl<'v> Visitor<'v> for IdentFinder {
-        fn visit_ident(&mut self, _: codemap::Span, id: ast::Ident){
+        fn visit_ident(&mut self, _: syntax_pos::Span, id: ast::Ident){
             self.ident_accumulator.push(id);
         }
     }
diff --git a/src/libsyntax/ext/quote.rs b/src/libsyntax/ext/quote.rs
index 871b0d4b1c0..db22eb7901c 100644
--- a/src/libsyntax/ext/quote.rs
+++ b/src/libsyntax/ext/quote.rs
@@ -9,7 +9,7 @@
 // except according to those terms.
 
 use ast::{self, Arg, Arm, Block, Expr, Item, Pat, Stmt, TokenTree, Ty};
-use codemap::Span;
+use syntax_pos::Span;
 use ext::base::ExtCtxt;
 use ext::base;
 use ext::build::AstBuilder;
@@ -36,7 +36,8 @@ pub mod rt {
     use ast::TokenTree;
 
     pub use parse::new_parser_from_tts;
-    pub use codemap::{BytePos, Span, dummy_spanned, DUMMY_SP};
+    pub use syntax_pos::{BytePos, Span, DUMMY_SP};
+    pub use codemap::{dummy_spanned};
 
     pub trait ToTokens {
         fn to_tokens(&self, _cx: &ExtCtxt) -> Vec<TokenTree>;
diff --git a/src/libsyntax/ext/source_util.rs b/src/libsyntax/ext/source_util.rs
index fd229d77966..a9b90dcbb7c 100644
--- a/src/libsyntax/ext/source_util.rs
+++ b/src/libsyntax/ext/source_util.rs
@@ -9,8 +9,7 @@
 // except according to those terms.
 
 use ast;
-use codemap::{Pos, Span};
-use codemap;
+use syntax_pos::{self, Pos, Span};
 use ext::base::*;
 use ext::base;
 use ext::build::AstBuilder;
@@ -194,7 +193,7 @@ pub fn expand_include_bytes(cx: &mut ExtCtxt, sp: Span, tts: &[ast::TokenTree])
 
 // resolve a file-system path to an absolute file-system path (if it
 // isn't already)
-fn res_rel_file(cx: &mut ExtCtxt, sp: codemap::Span, arg: &Path) -> PathBuf {
+fn res_rel_file(cx: &mut ExtCtxt, sp: syntax_pos::Span, arg: &Path) -> PathBuf {
     // NB: relative paths are resolved relative to the compilation unit
     if !arg.is_absolute() {
         let mut cu = PathBuf::from(&cx.codemap().span_to_filename(sp));
diff --git a/src/libsyntax/ext/tt/macro_parser.rs b/src/libsyntax/ext/tt/macro_parser.rs
index ca5eb8f8003..2230da10552 100644
--- a/src/libsyntax/ext/tt/macro_parser.rs
+++ b/src/libsyntax/ext/tt/macro_parser.rs
@@ -80,8 +80,8 @@ use self::TokenTreeOrTokenTreeVec::*;
 
 use ast;
 use ast::{TokenTree, Name, Ident};
-use codemap::{BytePos, mk_sp, Span, Spanned};
-use codemap;
+use syntax_pos::{self, BytePos, mk_sp, Span};
+use codemap::Spanned;
 use errors::FatalError;
 use parse::lexer::*; //resolve bug?
 use parse::ParseSess;
@@ -196,7 +196,7 @@ pub fn initial_matcher_pos(ms: Rc<Vec<TokenTree>>, sep: Option<Token>, lo: ByteP
 /// token tree it was derived from.
 
 pub enum NamedMatch {
-    MatchedSeq(Vec<Rc<NamedMatch>>, codemap::Span),
+    MatchedSeq(Vec<Rc<NamedMatch>>, syntax_pos::Span),
     MatchedNonterminal(Nonterminal)
 }
 
@@ -204,7 +204,7 @@ pub fn nameize(p_s: &ParseSess, ms: &[TokenTree], res: &[Rc<NamedMatch>])
             -> ParseResult<HashMap<Name, Rc<NamedMatch>>> {
     fn n_rec(p_s: &ParseSess, m: &TokenTree, res: &[Rc<NamedMatch>],
              ret_val: &mut HashMap<Name, Rc<NamedMatch>>, idx: &mut usize)
-             -> Result<(), (codemap::Span, String)> {
+             -> Result<(), (syntax_pos::Span, String)> {
         match *m {
             TokenTree::Sequence(_, ref seq) => {
                 for next_m in &seq.tts {
@@ -251,9 +251,9 @@ pub fn nameize(p_s: &ParseSess, ms: &[TokenTree], res: &[Rc<NamedMatch>])
 pub enum ParseResult<T> {
     Success(T),
     /// Arm failed to match
-    Failure(codemap::Span, String),
+    Failure(syntax_pos::Span, String),
     /// Fatal error (malformed macro?). Abort compilation.
-    Error(codemap::Span, String)
+    Error(syntax_pos::Span, String)
 }
 
 pub type NamedParseResult = ParseResult<HashMap<Name, Rc<NamedMatch>>>;
diff --git a/src/libsyntax/ext/tt/macro_rules.rs b/src/libsyntax/ext/tt/macro_rules.rs
index fe98394c3e4..850fbb5addf 100644
--- a/src/libsyntax/ext/tt/macro_rules.rs
+++ b/src/libsyntax/ext/tt/macro_rules.rs
@@ -9,7 +9,7 @@
 // except according to those terms.
 
 use ast::{self, TokenTree};
-use codemap::{Span, DUMMY_SP};
+use syntax_pos::{Span, DUMMY_SP};
 use ext::base::{DummyResult, ExtCtxt, MacResult, SyntaxExtension};
 use ext::base::{NormalTT, TTMacroExpander};
 use ext::tt::macro_parser::{Success, Error, Failure};
diff --git a/src/libsyntax/ext/tt/transcribe.rs b/src/libsyntax/ext/tt/transcribe.rs
index 6b3b5ce9de9..8b5ecd10fcb 100644
--- a/src/libsyntax/ext/tt/transcribe.rs
+++ b/src/libsyntax/ext/tt/transcribe.rs
@@ -11,7 +11,7 @@ use self::LockstepIterSize::*;
 
 use ast;
 use ast::{TokenTree, Ident, Name};
-use codemap::{Span, DUMMY_SP};
+use syntax_pos::{Span, DUMMY_SP};
 use errors::{Handler, DiagnosticBuilder};
 use ext::tt::macro_parser::{NamedMatch, MatchedSeq, MatchedNonterminal};
 use parse::token::{DocComment, MatchNt, SubstNt};