Rollup merge of rust-lang#49035 - klnusbaum:49001_epoch, r=Manishearth

rename epoch to edition

As outlined in rust-lang#49001 we'd like to rename all instances of `epoch` to `edition`. I developed the following bash script to assist in the rename. It renames all instances of `epoch` to `edition` and `Epoch` to `Edition` in all of the files I was able to determine were relevant. It then renames a few relevant files that had `epoch` in there name and finally prints out all of the remaining instance of the strings `epoch` and `Epoch` (which, as far as I can tell should not be changed). Here is the script:

```
replace() {
	sed -i '' "s/epoch/edition/g" "$1"
    sed -i '' "s/Epoch/Edition/g" "$1"
}

replace "src/librustc/lint/context.rs"
replace "src/librustc/lint/mod.rs"
replace "src/librustc/session/config.rs"
replace "src/librustc/session/mod.rs"
replace "src/librustc_driver/driver.rs"
replace "src/librustc_lint/lib.rs"
replace "src/librustc_typeck/check/method/probe.rs"
replace "src/libsyntax/config.rs"
replace "src/libsyntax/epoch.rs"
replace "src/libsyntax/feature_gate.rs"
replace "src/libsyntax/lib.rs"
replace "src/test/compile-fail/epoch-raw-pointer-method-2015.rs"
replace "src/test/compile-fail/epoch-raw-pointer-method-2018.rs"
replace "src/test/run-pass/dyn-trait.rs"
replace "src/test/run-pass/epoch-gate-feature.rs"
replace "src/test/ui/inference-variable-behind-raw-pointer.stderr"

git mv src/libsyntax/epoch.rs src/libsyntax/edition.rs
git mv src/test/compile-fail/epoch-raw-pointer-method-2015.rs src/test/compile-fail/edition-raw-pointer-method-2015.rs
git mv src/test/compile-fail/epoch-raw-pointer-method-2018.rs src/test/compile-fail/edition-raw-pointer-method-2018.rs

git grep "epoch" ./*
git grep "Epoch" ./*
```
And here is the output of the script:
```
kurtis-rust$ ./epoch_to_edition.sh
src/Cargo.lock: "crossbeam-epoch 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
src/Cargo.lock:name = "crossbeam-epoch"
src/Cargo.lock:"checksum crossbeam-epoch 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "59796cc6cbbdc6bb319161349db0c3250ec73ec7fcb763a51065ec4e2e158552"
src/ci/docker/scripts/android-start-emulator.sh:# Using the default qemu2 engine makes time::tests::since_epoch fails because
src/ci/docker/scripts/android-start-emulator.sh:# the emulator date is set to unix epoch (in armeabi-v7a-18 image). Using
src/librustc_incremental/persist/fs.rs:    let micros_since_unix_epoch = u64::from_str_radix(s, INT_ENCODE_BASE as u32);
src/librustc_incremental/persist/fs.rs:    if micros_since_unix_epoch.is_err() {
src/librustc_incremental/persist/fs.rs:    let micros_since_unix_epoch = micros_since_unix_epoch.unwrap();
src/librustc_incremental/persist/fs.rs:    let duration = Duration::new(micros_since_unix_epoch / 1_000_000,
src/librustc_incremental/persist/fs.rs:                                 1000 * (micros_since_unix_epoch % 1_000_000) as u32);
src/libstd/sys/cloudabi/abi/cloudabi.rs:  /// The epoch of this clock is undefined. The absolute
src/libstd/time.rs:        let one_second_from_epoch = UNIX_EPOCH + Duration::new(1, 0);
src/libstd/time.rs:        let one_second_from_epoch2 = UNIX_EPOCH + Duration::new(0, 500_000_000)
src/libstd/time.rs:        assert_eq!(one_second_from_epoch, one_second_from_epoch2);
src/libstd/time.rs:    fn since_epoch() {
src/test/run-pass/issue-29540.rs:    pub mon_min_osdmap_epochs: String,
src/test/run-pass/issue-29540.rs:    pub mon_max_pgmap_epochs: String,
src/test/run-pass/issue-29540.rs:    pub mon_max_log_epochs: String,
src/test/run-pass/issue-29540.rs:    pub mon_max_mdsmap_epochs: String,
src/test/run-pass/issue-29540.rs:    pub osd_map_share_max_epochs: String,
src/test/run-pass/issue-29540.rs:    pub osd_pg_epoch_persisted_max_stale: String,
```

If it looks like I've missed any things that should be converted, please let me know. There were also some notes in `src/libsyntax/epoch.rs` that indicated there might be some necessary/parallel changes that need to made in cargo. But we should probably make a separate issue for that.

src/librustc/lint/context.rs

@@ -41,7 +41,7 @@ use util::nodemap::FxHashMap;
 use std::default::Default as StdDefault;
 use std::cell::{Ref, RefCell};
 use syntax::ast;
-use syntax::epoch;
+use syntax::edition;
 use syntax_pos::{MultiSpan, Span};
 use errors::DiagnosticBuilder;
 use hir;
@@ -103,9 +103,9 @@ pub struct FutureIncompatibleInfo {
     pub id: LintId,
     /// e.g., a URL for an issue/PR/RFC or error code
     pub reference: &'static str,
-    /// If this is an epoch fixing lint, the epoch in which
+    /// If this is an edition fixing lint, the edition in which
     /// this lint becomes obsolete
-    pub epoch: Option<epoch::Epoch>,
+    pub edition: Option<edition::Edition>,
 }
 
 /// The target of the `by_name` map, which accounts for renaming/deprecation.
@@ -201,11 +201,11 @@ impl LintStore {
                                         sess: Option<&Session>,
                                         lints: Vec<FutureIncompatibleInfo>) {
 
-        for epoch in epoch::ALL_EPOCHS {
-            let lints = lints.iter().filter(|f| f.epoch == Some(*epoch)).map(|f| f.id)
+        for edition in edition::ALL_EDITIONS {
+            let lints = lints.iter().filter(|f| f.edition == Some(*edition)).map(|f| f.id)
                              .collect::<Vec<_>>();
             if !lints.is_empty() {
-                self.register_group(sess, false, epoch.lint_name(), lints)
+                self.register_group(sess, false, edition.lint_name(), lints)
             }
         }
 

src/librustc/lint/mod.rs

@@ -42,7 +42,7 @@ use session::{Session, DiagnosticMessageId};
 use std::hash;
 use syntax::ast;
 use syntax::codemap::MultiSpan;
-use syntax::epoch::Epoch;
+use syntax::edition::Edition;
 use syntax::symbol::Symbol;
 use syntax::visit as ast_visit;
 use syntax_pos::Span;
@@ -77,8 +77,8 @@ pub struct Lint {
     /// e.g. "imports that are never used"
     pub desc: &'static str,
 
-    /// Deny lint after this epoch
-    pub epoch_deny: Option<Epoch>,
+    /// Deny lint after this edition
+    pub edition_deny: Option<Edition>,
 }
 
 impl Lint {
@@ -88,8 +88,8 @@ impl Lint {
     }
 
     pub fn default_level(&self, session: &Session) -> Level {
-        if let Some(epoch_deny) = self.epoch_deny {
-            if session.epoch() >= epoch_deny {
+        if let Some(edition_deny) = self.edition_deny {
+            if session.edition() >= edition_deny {
                 return Level::Deny
             }
         }
@@ -100,20 +100,20 @@ impl Lint {
 /// Declare a static item of type `&'static Lint`.
 #[macro_export]
 macro_rules! declare_lint {
-    ($vis: vis $NAME: ident, $Level: ident, $desc: expr, $epoch: expr) => (
+    ($vis: vis $NAME: ident, $Level: ident, $desc: expr, $edition: expr) => (
         $vis static $NAME: &$crate::lint::Lint = &$crate::lint::Lint {
             name: stringify!($NAME),
             default_level: $crate::lint::$Level,
             desc: $desc,
-            epoch_deny: Some($epoch)
+            edition_deny: Some($edition)
         };
     );
     ($vis: vis $NAME: ident, $Level: ident, $desc: expr) => (
         $vis static $NAME: &$crate::lint::Lint = &$crate::lint::Lint {
             name: stringify!($NAME),
             default_level: $crate::lint::$Level,
             desc: $desc,
-            epoch_deny: None,
+            edition_deny: None,
         };
     );
 }
@@ -499,8 +499,8 @@ pub fn struct_lint_level<'a>(sess: &'a Session,
     // Check for future incompatibility lints and issue a stronger warning.
     let lints = sess.lint_store.borrow();
     if let Some(future_incompatible) = lints.future_incompatible(LintId::of(lint)) {
-        let future = if let Some(epoch) = future_incompatible.epoch {
-            format!("the {} epoch", epoch)
+        let future = if let Some(edition) = future_incompatible.edition {
+            format!("the {} edition", edition)
         } else {
             "a future release".to_owned()
         };

src/librustc/session/config.rs

@@ -28,7 +28,7 @@ use middle::cstore;
 
 use syntax::ast::{self, IntTy, UintTy};
 use syntax::codemap::{FileName, FilePathMapping};
-use syntax::epoch::Epoch;
+use syntax::edition::Edition;
 use syntax::parse::token;
 use syntax::parse;
 use syntax::symbol::Symbol;
@@ -771,7 +771,7 @@ macro_rules! options {
             Some("`string` or `string=string`");
         pub const parse_lto: Option<&'static str> =
             Some("one of `thin`, `fat`, or omitted");
-        pub const parse_epoch: Option<&'static str> =
+        pub const parse_edition: Option<&'static str> =
             Some("one of: `2015`, `2018`");
     }
 
@@ -780,7 +780,7 @@ macro_rules! options {
         use super::{$struct_name, Passes, SomePasses, AllPasses, Sanitizer, Lto};
         use rustc_back::{LinkerFlavor, PanicStrategy, RelroLevel};
         use std::path::PathBuf;
-        use syntax::epoch::Epoch;
+        use syntax::edition::Edition;
 
         $(
             pub fn $opt(cg: &mut $struct_name, v: Option<&str>) -> bool {
@@ -983,11 +983,11 @@ macro_rules! options {
             true
         }
 
-        fn parse_epoch(slot: &mut Epoch, v: Option<&str>) -> bool {
+        fn parse_edition(slot: &mut Edition, v: Option<&str>) -> bool {
             match v {
                 Some(s) => {
-                    let epoch = s.parse();
-                    if let Ok(parsed) = epoch {
+                    let edition = s.parse();
+                    if let Ok(parsed) = edition {
                         *slot = parsed;
                         true
                     } else {
@@ -1280,10 +1280,10 @@ options! {DebuggingOptions, DebuggingSetter, basic_debugging_options,
         `everybody_loops` (all function bodies replaced with `loop {}`),
         `hir` (the HIR), `hir,identified`, or
         `hir,typed` (HIR with types for each node)."),
-    epoch: Epoch = (Epoch::Epoch2015, parse_epoch, [TRACKED],
-        "The epoch to build Rust with. Newer epochs may include features
-         that require breaking changes. The default epoch is 2015 (the first
-         epoch). Crates compiled with different epochs can be linked together."),
+    edition: Edition = (Edition::Edition2015, parse_edition, [TRACKED],
+        "The edition to build Rust with. Newer editions may include features
+         that require breaking changes. The default edition is 2015 (the first
+         edition). Crates compiled with different editions can be linked together."),
     run_dsymutil: Option<bool> = (None, parse_opt_bool, [TRACKED],
           "run `dsymutil` and delete intermediate object files"),
     ui_testing: bool = (false, parse_bool, [UNTRACKED],
@@ -2258,7 +2258,7 @@ mod dep_tracking {
     use std::hash::Hash;
     use std::path::PathBuf;
     use std::collections::hash_map::DefaultHasher;
-    use super::{CrateType, DebugInfoLevel, Epoch, ErrorOutputType, Lto, OptLevel, OutputTypes,
+    use super::{CrateType, DebugInfoLevel, Edition, ErrorOutputType, Lto, OptLevel, OutputTypes,
                 Passes, Sanitizer};
     use syntax::feature_gate::UnstableFeatures;
     use rustc_back::{PanicStrategy, RelroLevel};
@@ -2320,7 +2320,7 @@ mod dep_tracking {
     impl_dep_tracking_hash_via_hash!(cstore::NativeLibraryKind);
     impl_dep_tracking_hash_via_hash!(Sanitizer);
     impl_dep_tracking_hash_via_hash!(Option<Sanitizer>);
-    impl_dep_tracking_hash_via_hash!(Epoch);
+    impl_dep_tracking_hash_via_hash!(Edition);
 
     impl_dep_tracking_hash_for_sortable_vec_of!(String);
     impl_dep_tracking_hash_for_sortable_vec_of!(PathBuf);

src/librustc/session/mod.rs

@@ -31,7 +31,7 @@ use rustc_data_structures::sync::{Lrc, Lock};
 use syntax::ast::NodeId;
 use errors::{self, DiagnosticBuilder, DiagnosticId};
 use errors::emitter::{Emitter, EmitterWriter};
-use syntax::epoch::Epoch;
+use syntax::edition::Edition;
 use syntax::json::JsonEmitter;
 use syntax::feature_gate;
 use syntax::symbol::Symbol;
@@ -976,13 +976,13 @@ impl Session {
         self.opts.debugging_opts.teach && !self.parse_sess.span_diagnostic.code_emitted(code)
     }
 
-    /// Are we allowed to use features from the Rust 2018 epoch?
+    /// Are we allowed to use features from the Rust 2018 edition?
     pub fn rust_2018(&self) -> bool {
-        self.opts.debugging_opts.epoch >= Epoch::Epoch2018
+        self.opts.debugging_opts.edition >= Edition::Edition2018
     }
 
-    pub fn epoch(&self) -> Epoch {
-        self.opts.debugging_opts.epoch
+    pub fn edition(&self) -> Edition {
+        self.opts.debugging_opts.edition
     }
 }
 

src/librustc_driver/driver.rs

@@ -648,7 +648,7 @@ pub fn phase_2_configure_and_expand_inner<'a, F>(sess: &'a Session,
 {
     let (mut krate, features) = syntax::config::features(krate, &sess.parse_sess,
                                                          sess.opts.test,
-                                                         sess.opts.debugging_opts.epoch);
+                                                         sess.opts.debugging_opts.edition);
     // these need to be set "early" so that expansion sees `quote` if enabled.
     sess.init_features(features);
 

src/librustc_lint/lib.rs

@@ -48,7 +48,7 @@ use rustc::session;
 use rustc::util;
 
 use session::Session;
-use syntax::epoch::Epoch;
+use syntax::edition::Edition;
 use lint::LintId;
 use lint::FutureIncompatibleInfo;
 
@@ -197,82 +197,82 @@ pub fn register_builtins(store: &mut lint::LintStore, sess: Option<&Session>) {
         FutureIncompatibleInfo {
             id: LintId::of(PRIVATE_IN_PUBLIC),
             reference: "issue #34537 <https://github.com/rust-lang/rust/issues/34537>",
-            epoch: None,
+            edition: None,
         },
         FutureIncompatibleInfo {
             id: LintId::of(PUB_USE_OF_PRIVATE_EXTERN_CRATE),
             reference: "issue #34537 <https://github.com/rust-lang/rust/issues/34537>",
-            epoch: None,
+            edition: None,
         },
         FutureIncompatibleInfo {
             id: LintId::of(PATTERNS_IN_FNS_WITHOUT_BODY),
             reference: "issue #35203 <https://github.com/rust-lang/rust/issues/35203>",
-            epoch: None,
+            edition: None,
         },
         FutureIncompatibleInfo {
             id: LintId::of(SAFE_EXTERN_STATICS),
             reference: "issue #36247 <https://github.com/rust-lang/rust/issues/36247>",
-            epoch: None,
+            edition: None,
         },
         FutureIncompatibleInfo {
             id: LintId::of(INVALID_TYPE_PARAM_DEFAULT),
             reference: "issue #36887 <https://github.com/rust-lang/rust/issues/36887>",
-            epoch: None,
+            edition: None,
         },
         FutureIncompatibleInfo {
             id: LintId::of(LEGACY_DIRECTORY_OWNERSHIP),
             reference: "issue #37872 <https://github.com/rust-lang/rust/issues/37872>",
-            epoch: None,
+            edition: None,
         },
         FutureIncompatibleInfo {
             id: LintId::of(LEGACY_IMPORTS),
             reference: "issue #38260 <https://github.com/rust-lang/rust/issues/38260>",
-            epoch: None,
+            edition: None,
         },
         FutureIncompatibleInfo {
             id: LintId::of(LEGACY_CONSTRUCTOR_VISIBILITY),
             reference: "issue #39207 <https://github.com/rust-lang/rust/issues/39207>",
-            epoch: None,
+            edition: None,
         },
         FutureIncompatibleInfo {
             id: LintId::of(MISSING_FRAGMENT_SPECIFIER),
             reference: "issue #40107 <https://github.com/rust-lang/rust/issues/40107>",
-            epoch: None,
+            edition: None,
         },
         FutureIncompatibleInfo {
             id: LintId::of(ILLEGAL_FLOATING_POINT_LITERAL_PATTERN),
             reference: "issue #41620 <https://github.com/rust-lang/rust/issues/41620>",
-            epoch: None,
+            edition: None,
         },
         FutureIncompatibleInfo {
             id: LintId::of(ANONYMOUS_PARAMETERS),
             reference: "issue #41686 <https://github.com/rust-lang/rust/issues/41686>",
-            epoch: None,
+            edition: None,
         },
         FutureIncompatibleInfo {
             id: LintId::of(PARENTHESIZED_PARAMS_IN_TYPES_AND_MODULES),
             reference: "issue #42238 <https://github.com/rust-lang/rust/issues/42238>",
-            epoch: None,
+            edition: None,
         },
         FutureIncompatibleInfo {
             id: LintId::of(LATE_BOUND_LIFETIME_ARGUMENTS),
             reference: "issue #42868 <https://github.com/rust-lang/rust/issues/42868>",
-            epoch: None,
+            edition: None,
         },
         FutureIncompatibleInfo {
             id: LintId::of(SAFE_PACKED_BORROWS),
             reference: "issue #46043 <https://github.com/rust-lang/rust/issues/46043>",
-            epoch: None,
+            edition: None,
         },
         FutureIncompatibleInfo {
             id: LintId::of(INCOHERENT_FUNDAMENTAL_IMPLS),
             reference: "issue #46205 <https://github.com/rust-lang/rust/issues/46205>",
-            epoch: None,
+            edition: None,
         },
         FutureIncompatibleInfo {
             id: LintId::of(TYVAR_BEHIND_RAW_POINTER),
             reference: "issue #46906 <https://github.com/rust-lang/rust/issues/46906>",
-            epoch: Some(Epoch::Epoch2018),
+            edition: Some(Edition::Edition2018),
         }
         ]);
 

src/librustc_typeck/check/method/probe.rs

@@ -326,7 +326,7 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
                     if reached_raw_pointer
                     && !self.tcx.features().arbitrary_self_types {
                         // this case used to be allowed by the compiler,
-                        // so we do a future-compat lint here for the 2015 epoch
+                        // so we do a future-compat lint here for the 2015 edition
                         // (see https://github.com/rust-lang/rust/issues/46906)
                         if self.tcx.sess.rust_2018() {
                           span_err!(self.tcx.sess, span, E0908,

src/libsyntax/config.rs

@@ -13,7 +13,7 @@ use feature_gate::{feature_err, EXPLAIN_STMT_ATTR_SYNTAX, Features, get_features
 use {fold, attr};
 use ast;
 use codemap::Spanned;
-use epoch::Epoch;
+use edition::Edition;
 use parse::{token, ParseSess};
 
 use ptr::P;
@@ -27,7 +27,7 @@ pub struct StripUnconfigured<'a> {
 }
 
 // `cfg_attr`-process the crate's attributes and compute the crate's features.
-pub fn features(mut krate: ast::Crate, sess: &ParseSess, should_test: bool, epoch: Epoch)
+pub fn features(mut krate: ast::Crate, sess: &ParseSess, should_test: bool, edition: Edition)
                 -> (ast::Crate, Features) {
     let features;
     {
@@ -47,7 +47,7 @@ pub fn features(mut krate: ast::Crate, sess: &ParseSess, should_test: bool, epoc
             return (krate, Features::new());
         }
 
-        features = get_features(&sess.span_diagnostic, &krate.attrs, epoch);
+        features = get_features(&sess.span_diagnostic, &krate.attrs, edition);
 
         // Avoid reconfiguring malformed `cfg_attr`s
         if err_count == sess.span_diagnostic.err_count() {