Move epochs to libsyntax

Author: Manishearth

src/librustc/lint/builtin.rs

@@ -17,8 +17,8 @@
 use errors::DiagnosticBuilder;
 use lint::{LintPass, LateLintPass, LintArray};
 use session::Session;
-use session::config::Epoch;
 use syntax::codemap::Span;
+use syntax::epoch::Epoch;
 
 declare_lint! {
     pub EXCEEDING_BITSHIFTS,

src/librustc/lint/context.rs

@@ -42,6 +42,7 @@ use util::nodemap::FxHashMap;
 use std::default::Default as StdDefault;
 use std::cell::{Ref, RefCell};
 use syntax::ast;
+use syntax::epoch;
 use syntax_pos::{MultiSpan, Span};
 use errors::DiagnosticBuilder;
 use hir;
@@ -105,7 +106,7 @@ pub struct FutureIncompatibleInfo {
     pub reference: &'static str,
     /// If this is an epoch fixing lint, the epoch in which
     /// this lint becomes obsolete
-    pub epoch: Option<config::Epoch>,
+    pub epoch: Option<epoch::Epoch>,
 }
 
 /// The target of the `by_name` map, which accounts for renaming/deprecation.
@@ -201,7 +202,7 @@ impl LintStore {
                                         sess: Option<&Session>,
                                         lints: Vec<FutureIncompatibleInfo>) {
 
-        for epoch in config::ALL_EPOCHS {
+        for epoch in epoch::ALL_EPOCHS {
             let lints = lints.iter().filter(|f| f.epoch == Some(*epoch)).map(|f| f.id)
                              .collect::<Vec<_>>();
             if !lints.is_empty() {

src/librustc/lint/mod.rs

@@ -38,10 +38,11 @@ use hir::def_id::{CrateNum, LOCAL_CRATE};
 use hir::intravisit::{self, FnKind};
 use hir;
 use lint::builtin::BuiltinLintDiagnostics;
-use session::{config, Session, DiagnosticMessageId};
+use session::{Session, DiagnosticMessageId};
 use std::hash;
 use syntax::ast;
 use syntax::codemap::MultiSpan;
+use syntax::epoch::Epoch;
 use syntax::symbol::Symbol;
 use syntax::visit as ast_visit;
 use syntax_pos::Span;
@@ -77,7 +78,7 @@ pub struct Lint {
     pub desc: &'static str,
 
     /// Deny lint after this epoch
-    pub epoch_deny: Option<config::Epoch>,
+    pub epoch_deny: Option<Epoch>,
 }
 
 impl Lint {

src/librustc/session/config.rs

@@ -28,6 +28,7 @@ use middle::cstore;
 
 use syntax::ast::{self, IntTy, UintTy};
 use syntax::codemap::{FileName, FilePathMapping};
+use syntax::epoch::Epoch;
 use syntax::parse::token;
 use syntax::parse;
 use syntax::symbol::Symbol;
@@ -111,59 +112,6 @@ pub enum OutputType {
     DepInfo,
 }
 
-/// The epoch of the compiler (RFC 2052)
-#[derive(Clone, Copy, Hash, PartialOrd, Ord, Eq, PartialEq, Debug)]
-#[non_exhaustive]
-pub enum Epoch {
-    // epochs must be kept in order, newest to oldest
-    /// The 2015 epoch
-    Epoch2015,
-    /// The 2018 epoch
-    Epoch2018,
-    // when adding new epochs, be sure to update:
-    //
-    // - the list in the `parse_epoch` static
-    // - the match in the `parse_epoch` function
-    // - add a `rust_####()` function to the session
-    // - update the enum in Cargo's sources as well
-    //
-    // When -Zepoch becomes --epoch, there will
-    // also be a check for the epoch being nightly-only
-    // somewhere. That will need to be updated
-    // whenever we're stabilizing/introducing a new epoch
-    // as well as changing the default Cargo template.
-}
-
-pub const ALL_EPOCHS: &[Epoch] = &[Epoch::Epoch2015, Epoch::Epoch2018];
-
-impl ToString for Epoch {
-    fn to_string(&self) -> String {
-        match *self {
-            Epoch::Epoch2015 => "2015".into(),
-            Epoch::Epoch2018 => "2018".into(),
-        }
-    }
-}
-
-impl Epoch {
-    pub fn lint_name(&self) -> &'static str {
-        match *self {
-            Epoch::Epoch2015 => "epoch_2015",
-            Epoch::Epoch2018 => "epoch_2018",
-        }
-    }
-}
-
-impl str::FromStr for Epoch {
-    type Err = ();
-    fn from_str(s: &str) -> Result<Self, ()> {
-        match s {
-            "2015" => Ok(Epoch::Epoch2015),
-            "2018" => Ok(Epoch::Epoch2018),
-            _ => Err(()),
-        }
-    }
-}
 
 impl_stable_hash_for!(enum self::OutputType {
     Bitcode,
@@ -829,9 +777,10 @@ macro_rules! options {
 
     #[allow(dead_code)]
     mod $mod_set {
-        use super::{$struct_name, Passes, SomePasses, AllPasses, Sanitizer, Lto, Epoch};
+        use super::{$struct_name, Passes, SomePasses, AllPasses, Sanitizer, Lto};
         use rustc_back::{LinkerFlavor, PanicStrategy, RelroLevel};
         use std::path::PathBuf;
+        use syntax::epoch::Epoch;
 
         $(
             pub fn $opt(cg: &mut $struct_name, v: Option<&str>) -> bool {

src/librustc/session/mod.rs

@@ -20,7 +20,7 @@ use lint::builtin::BuiltinLintDiagnostics;
 use middle::allocator::AllocatorKind;
 use middle::dependency_format;
 use session::search_paths::PathKind;
-use session::config::{DebugInfoLevel, Epoch, OutputType};
+use session::config::{DebugInfoLevel, OutputType};
 use ty::tls;
 use util::nodemap::{FxHashMap, FxHashSet};
 use util::common::{duration_to_secs_str, ErrorReported};
@@ -30,6 +30,7 @@ use rustc_data_structures::sync::Lrc;
 use syntax::ast::NodeId;
 use errors::{self, DiagnosticBuilder, DiagnosticId};
 use errors::emitter::{Emitter, EmitterWriter};
+use syntax::epoch::Epoch;
 use syntax::json::JsonEmitter;
 use syntax::feature_gate;
 use syntax::symbol::Symbol;

src/librustc_lint/lib.rs

@@ -47,6 +47,7 @@ use rustc::session;
 use rustc::util;
 
 use session::Session;
+use syntax::epoch::Epoch;
 use lint::LintId;
 use lint::FutureIncompatibleInfo;
 
@@ -279,7 +280,7 @@ pub fn register_builtins(store: &mut lint::LintStore, sess: Option<&Session>) {
          FutureIncompatibleInfo {
              id: LintId::of(lint::builtin::BARE_TRAIT_OBJECT),
              reference: "issue #48457 <https://github.com/rust-lang/rust/issues/48457>",
-             epoch: Some(session::config::Epoch::Epoch2018),
+             epoch: Some(Epoch::Epoch2018),
          }
         ]);
 

src/libsyntax/epoch.rs

@@ -0,0 +1,67 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+use std::str::FromStr;
+
+/// The epoch of the compiler (RFC 2052)
+#[derive(Clone, Copy, Hash, PartialOrd, Ord, Eq, PartialEq, Debug)]
+#[non_exhaustive]
+pub enum Epoch {
+    // epochs must be kept in order, newest to oldest
+
+    /// The 2015 epoch
+    Epoch2015,
+    /// The 2018 epoch
+    Epoch2018,
+
+    // when adding new epochs, be sure to update:
+    //
+    // - the list in the `parse_epoch` static in librustc::session::config
+    // - add a `rust_####()` function to the session
+    // - update the enum in Cargo's sources as well
+    //
+    // When -Zepoch becomes --epoch, there will
+    // also be a check for the epoch being nightly-only
+    // somewhere. That will need to be updated
+    // whenever we're stabilizing/introducing a new epoch
+    // as well as changing the default Cargo template.
+}
+
+// must be in order from oldest to newest
+pub const ALL_EPOCHS: &[Epoch] = &[Epoch::Epoch2015, Epoch::Epoch2018];
+
+impl ToString for Epoch {
+    fn to_string(&self) -> String {
+        match *self {
+            Epoch::Epoch2015 => "2015".into(),
+            Epoch::Epoch2018 => "2018".into(),
+        }
+    }
+}
+
+impl Epoch {
+    pub fn lint_name(&self) -> &'static str {
+        match *self {
+            Epoch::Epoch2015 => "epoch_2015",
+            Epoch::Epoch2018 => "epoch_2018",
+        }
+    }
+}
+
+impl FromStr for Epoch {
+    type Err = ();
+    fn from_str(s: &str) -> Result<Self, ()> {
+        match s {
+            "2015" => Ok(Epoch::Epoch2015),
+            "2018" => Ok(Epoch::Epoch2018),
+            _ => Err(())
+        }
+    }
+}

src/libsyntax/lib.rs

@@ -23,6 +23,7 @@
 #![feature(unicode)]
 #![feature(rustc_diagnostic_macros)]
 #![feature(match_default_bindings)]
+#![feature(non_exhaustive)]
 #![feature(i128_type)]
 #![feature(const_atomic_usize_new)]
 #![feature(rustc_attrs)]
@@ -114,6 +115,7 @@ pub mod codemap;
 #[macro_use]
 pub mod config;
 pub mod entry;
+pub mod epoch;
 pub mod feature_gate;
 pub mod fold;
 pub mod parse;