serialize: Fully deprecate the library

This commit completes the deprecation story for the in-tree serialization
library. The compiler will now emit a warning whenever it encounters
`deriving(Encodable)` or `deriving(Decodable)`, and the library itself is now
marked `#[unstable]` for when feature staging is enabled.

All users of serialization can migrate to the `rustc-serialize` crate on
crates.io which provides the exact same interface as the libserialize library
in-tree. The new deriving modes are named `RustcEncodable` and `RustcDecodable`
and require `extern crate "rustc-serialize" as rustc_serialize` at the crate
root in order to expand correctly.

To migrate all crates, add the following to your `Cargo.toml`:

    [dependencies]
    rustc-serialize = "0.1.1"

And then add the following to your crate root:

    extern crate "rustc-serialize" as rustc_serialize;

Finally, rename `Encodable` and `Decodable` deriving modes to `RustcEncodable`
and `RustcDecodable`.

[breaking-change]

src/librustc/lib.rs

@@ -40,6 +40,8 @@ extern crate collections;
 #[phase(plugin, link)] extern crate log;
 #[phase(plugin, link)] extern crate syntax;
 
+extern crate "serialize" as rustc_serialize; // used by deriving
+
 #[cfg(test)]
 extern crate test;
 

src/librustc/middle/def.rs

@@ -20,7 +20,7 @@ use syntax::ast_util::local_def;
 
 use std::cell::RefCell;
 
-#[deriving(Clone, Copy, PartialEq, Eq, Encodable, Decodable, Hash, Show)]
+#[deriving(Clone, Copy, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Show)]
 pub enum Def {
     DefFn(ast::DefId, bool /* is_ctor */),
     DefStaticMethod(/* method */ ast::DefId, MethodProvenance),
@@ -73,13 +73,13 @@ pub struct Export {
     pub def_id: ast::DefId, // The definition of the target.
 }
 
-#[deriving(Clone, Copy, PartialEq, Eq, Encodable, Decodable, Hash, Show)]
+#[deriving(Clone, Copy, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Show)]
 pub enum MethodProvenance {
     FromTrait(ast::DefId),
     FromImpl(ast::DefId),
 }
 
-#[deriving(Clone, Copy, PartialEq, Eq, Encodable, Decodable, Hash, Show)]
+#[deriving(Clone, Copy, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Show)]
 pub enum TyParamProvenance {
     FromSelf(ast::DefId),
     FromParam(ast::DefId),

src/librustc/middle/region.rs

@@ -36,7 +36,8 @@ use syntax::visit::{Visitor, FnKind};
 /// placate the same deriving in `ty::FreeRegion`, but we may want to
 /// actually attach a more meaningful ordering to scopes than the one
 /// generated via deriving here.
-#[deriving(Clone, Copy, PartialEq, PartialOrd, Eq, Ord, Hash, Encodable, Decodable, Show)]
+#[deriving(Clone, PartialEq, PartialOrd, Eq, Ord, Hash, RustcEncodable,
+           RustcDecodable, Show, Copy)]
 pub enum CodeExtent {
     Misc(ast::NodeId)
 }

src/librustc/middle/resolve_lifetime.rs

@@ -33,7 +33,7 @@ use syntax::visit;
 use syntax::visit::Visitor;
 use util::nodemap::NodeMap;
 
-#[deriving(Clone, Copy, PartialEq, Eq, Hash, Encodable, Decodable, Show)]
+#[deriving(Clone, Copy, PartialEq, Eq, Hash, RustcEncodable, RustcDecodable, Show)]
 pub enum DefRegion {
     DefStaticRegion,
     DefEarlyBoundRegion(/* space */ subst::ParamSpace,

src/librustc/middle/subst.rs

@@ -187,8 +187,8 @@ impl RegionSubsts {
 ///////////////////////////////////////////////////////////////////////////
 // ParamSpace
 
-#[deriving(Copy, PartialOrd, Ord, PartialEq, Eq,
-           Clone, Hash, Encodable, Decodable, Show)]
+#[deriving(PartialOrd, Ord, PartialEq, Eq, Copy,
+           Clone, Hash, RustcEncodable, RustcDecodable, Show)]
 pub enum ParamSpace {
     TypeSpace,  // Type parameters attached to a type definition, trait, or impl
     SelfSpace,  // Self parameter on a trait
@@ -224,7 +224,7 @@ impl ParamSpace {
 /// Vector of things sorted by param space. Used to keep
 /// the set of things declared on the type, self, or method
 /// distinct.
-#[deriving(PartialEq, Eq, Clone, Hash, Encodable, Decodable)]
+#[deriving(PartialEq, Eq, Clone, Hash, RustcEncodable, RustcDecodable)]
 pub struct VecPerParamSpace<T> {
     // This was originally represented as a tuple with one Vec<T> for
     // each variant of ParamSpace, and that remains the abstraction

src/librustc/middle/ty.rs

@@ -246,7 +246,7 @@ pub struct mt<'tcx> {
     pub mutbl: ast::Mutability,
 }
 
-#[deriving(Clone, Copy, PartialEq, Eq, Hash, Encodable, Decodable, Show)]
+#[deriving(Clone, Copy, PartialEq, Eq, Hash, RustcEncodable, RustcDecodable, Show)]
 pub enum TraitStore {
     /// Box<Trait>
     UniqTraitStore,
@@ -277,13 +277,13 @@ pub enum ast_ty_to_ty_cache_entry<'tcx> {
     atttce_resolved(Ty<'tcx>)  /* resolved to a type, irrespective of region */
 }
 
-#[deriving(Clone, PartialEq, Decodable, Encodable)]
+#[deriving(Clone, PartialEq, RustcDecodable, RustcEncodable)]
 pub struct ItemVariances {
     pub types: VecPerParamSpace<Variance>,
     pub regions: VecPerParamSpace<Variance>,
 }
 
-#[deriving(Clone, Copy, PartialEq, Decodable, Encodable, Show)]
+#[deriving(Clone, PartialEq, RustcDecodable, RustcEncodable, Show, Copy)]
 pub enum Variance {
     Covariant,      // T<A> <: T<B> iff A <: B -- e.g., function return type
     Invariant,      // T<A> <: T<B> iff B == A -- e.g., type of mutable cell
@@ -430,7 +430,7 @@ pub fn type_of_adjust<'tcx>(cx: &ctxt<'tcx>, adj: &AutoAdjustment<'tcx>) -> Opti
     }
 }
 
-#[deriving(Clone, Copy, Encodable, Decodable, PartialEq, PartialOrd, Show)]
+#[deriving(Clone, Copy, RustcEncodable, RustcDecodable, PartialEq, PartialOrd, Show)]
 pub struct param_index {
     pub space: subst::ParamSpace,
     pub index: uint
@@ -510,7 +510,7 @@ pub struct MethodCall {
     pub adjustment: ExprAdjustment
 }
 
-#[deriving(Clone, Copy, PartialEq, Eq, Hash, Show, Encodable, Decodable)]
+#[deriving(Clone, PartialEq, Eq, Hash, Show, RustcEncodable, RustcDecodable, Copy)]
 pub enum ExprAdjustment {
     NoAdjustment,
     AutoDeref(uint),
@@ -973,15 +973,15 @@ pub struct ParamTy {
 /// is the outer fn.
 ///
 /// [dbi]: http://en.wikipedia.org/wiki/De_Bruijn_index
-#[deriving(Clone, Copy, PartialEq, Eq, Hash, Encodable, Decodable, Show)]
+#[deriving(Clone, PartialEq, Eq, Hash, RustcEncodable, RustcDecodable, Show, Copy)]
 pub struct DebruijnIndex {
     // We maintain the invariant that this is never 0. So 1 indicates
     // the innermost binder. To ensure this, create with `DebruijnIndex::new`.
     pub depth: uint,
 }
 
 /// Representation of regions:
-#[deriving(Clone, Copy, PartialEq, Eq, Hash, Encodable, Decodable, Show)]
+#[deriving(Clone, PartialEq, Eq, Hash, RustcEncodable, RustcDecodable, Show, Copy)]
 pub enum Region {
     // Region bound in a type or fn declaration which will be
     // substituted 'early' -- that is, at the same time when type
@@ -1028,7 +1028,7 @@ pub struct UpvarId {
     pub closure_expr_id: ast::NodeId,
 }
 
-#[deriving(Clone, Copy, PartialEq, Eq, Hash, Show, Encodable, Decodable)]
+#[deriving(Clone, PartialEq, Eq, Hash, Show, RustcEncodable, RustcDecodable, Copy)]
 pub enum BorrowKind {
     /// Data must be immutable and is aliasable.
     ImmBorrow,
@@ -1121,7 +1121,7 @@ pub enum BorrowKind {
 /// - Through mutation, the borrowed upvars can actually escape
 ///   the closure, so sometimes it is necessary for them to be larger
 ///   than the closure lifetime itself.
-#[deriving(Copy, PartialEq, Clone, Encodable, Decodable, Show)]
+#[deriving(PartialEq, Clone, RustcEncodable, RustcDecodable, Show, Copy)]
 pub struct UpvarBorrow {
     pub kind: BorrowKind,
     pub region: ty::Region,
@@ -1146,15 +1146,17 @@ impl Region {
     }
 }
 
-#[deriving(Clone, Copy, PartialEq, PartialOrd, Eq, Ord, Hash, Encodable, Decodable, Show)]
+#[deriving(Clone, PartialEq, PartialOrd, Eq, Ord, Hash,
+           RustcEncodable, RustcDecodable, Show, Copy)]
 /// A "free" region `fr` can be interpreted as "some region
 /// at least as big as the scope `fr.scope`".
 pub struct FreeRegion {
     pub scope: region::CodeExtent,
     pub bound_region: BoundRegion
 }
 
-#[deriving(Clone, Copy, PartialEq, PartialOrd, Eq, Ord, Hash, Encodable, Decodable, Show)]
+#[deriving(Clone, PartialEq, PartialOrd, Eq, Ord, Hash,
+           RustcEncodable, RustcDecodable, Show, Copy)]
 pub enum BoundRegion {
     /// An anonymous region parameter for a given fn (&T)
     BrAnon(uint),
@@ -1412,7 +1414,8 @@ pub struct ExistentialBounds {
 
 pub type BuiltinBounds = EnumSet<BuiltinBound>;
 
-#[deriving(Copy, Clone, Encodable, PartialEq, Eq, Decodable, Hash, Show)]
+#[deriving(Clone, RustcEncodable, PartialEq, Eq, RustcDecodable, Hash,
+           Show, Copy)]
 #[repr(uint)]
 pub enum BuiltinBound {
     BoundSend,
@@ -1463,7 +1466,7 @@ pub struct FloatVid {
     pub index: uint
 }
 
-#[deriving(Clone, Copy, PartialEq, Eq, Encodable, Decodable, Hash)]
+#[deriving(Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Copy)]
 pub struct RegionVid {
     pub index: uint
 }
@@ -1485,7 +1488,7 @@ pub enum InferTy {
     FreshIntTy(uint),
 }
 
-#[deriving(Clone, Copy, Encodable, Decodable, Eq, Hash, Show)]
+#[deriving(Clone, RustcEncodable, RustcDecodable, Eq, Hash, Show, Copy)]
 pub enum InferRegion {
     ReVar(RegionVid),
     ReSkolemized(uint, BoundRegion)
@@ -1571,7 +1574,7 @@ pub struct TypeParameterDef<'tcx> {
     pub default: Option<Ty<'tcx>>,
 }
 
-#[deriving(Encodable, Decodable, Clone, Show)]
+#[deriving(RustcEncodable, RustcDecodable, Clone, Show)]
 pub struct RegionParameterDef {
     pub name: ast::Name,
     pub def_id: ast::DefId,
@@ -6223,7 +6226,7 @@ pub fn accumulate_lifetimes_in_type(accumulator: &mut Vec<ty::Region>,
 }
 
 /// A free variable referred to in a function.
-#[deriving(Copy, Encodable, Decodable)]
+#[deriving(Copy, RustcEncodable, RustcDecodable)]
 pub struct Freevar {
     /// The variable being accessed free.
     pub def: def::Def,