diff options
39 files changed, 726 insertions, 781 deletions
diff --git a/compiler/rustc_ast/src/ast.rs b/compiler/rustc_ast/src/ast.rs index 0dd10a1d066..7c19559ed91 100644 --- a/compiler/rustc_ast/src/ast.rs +++ b/compiler/rustc_ast/src/ast.rs @@ -2418,8 +2418,9 @@ impl<S: Encoder> rustc_serialize::Encodable<S> for AttrId { } impl<D: Decoder> rustc_serialize::Decodable<D> for AttrId { - fn decode(d: &mut D) -> Result<AttrId, D::Error> { - d.read_unit().map(|_| crate::attr::mk_attr_id()) + fn decode(d: &mut D) -> AttrId { + d.read_unit(); + crate::attr::mk_attr_id() } } diff --git a/compiler/rustc_ast/src/ptr.rs b/compiler/rustc_ast/src/ptr.rs index 9fe87a0a637..70dbda82224 100644 --- a/compiler/rustc_ast/src/ptr.rs +++ b/compiler/rustc_ast/src/ptr.rs @@ -115,8 +115,8 @@ impl<T> fmt::Pointer for P<T> { } impl<D: Decoder, T: 'static + Decodable<D>> Decodable<D> for P<T> { - fn decode(d: &mut D) -> Result<P<T>, D::Error> { - Decodable::decode(d).map(P) + fn decode(d: &mut D) -> P<T> { + P(Decodable::decode(d)) } } @@ -204,8 +204,8 @@ impl<S: Encoder, T: Encodable<S>> Encodable<S> for P<[T]> { } impl<D: Decoder, T: Decodable<D>> Decodable<D> for P<[T]> { - fn decode(d: &mut D) -> Result<P<[T]>, D::Error> { - Ok(P::from_vec(Decodable::decode(d)?)) + fn decode(d: &mut D) -> P<[T]> { + P::from_vec(Decodable::decode(d)) } } diff --git a/compiler/rustc_ast/src/tokenstream.rs b/compiler/rustc_ast/src/tokenstream.rs index 51cabb50cd3..2174378a560 100644 --- a/compiler/rustc_ast/src/tokenstream.rs +++ b/compiler/rustc_ast/src/tokenstream.rs @@ -163,7 +163,7 @@ impl<S: Encoder> Encodable<S> for LazyTokenStream { } impl<D: Decoder> Decodable<D> for LazyTokenStream { - fn decode(_d: &mut D) -> Result<Self, D::Error> { + fn decode(_d: &mut D) -> Self { panic!("Attempted to decode LazyTokenStream"); } } diff --git a/compiler/rustc_data_structures/src/fingerprint.rs b/compiler/rustc_data_structures/src/fingerprint.rs index c9af35da4bc..525cd650dd2 100644 --- a/compiler/rustc_data_structures/src/fingerprint.rs +++ b/compiler/rustc_data_structures/src/fingerprint.rs @@ -149,10 +149,10 @@ impl<E: rustc_serialize::Encoder> Encodable<E> for Fingerprint { impl<D: rustc_serialize::Decoder> Decodable<D> for Fingerprint { #[inline] - fn decode(d: &mut D) -> Result<Self, D::Error> { + fn decode(d: &mut D) -> Self { let mut bytes = [0u8; 16]; - d.read_raw_bytes_into(&mut bytes)?; - Ok(Fingerprint::from_le_bytes(bytes)) + d.read_raw_bytes_into(&mut bytes); + Fingerprint::from_le_bytes(bytes) } } @@ -195,8 +195,8 @@ impl<E: rustc_serialize::Encoder> Encodable<E> for PackedFingerprint { impl<D: rustc_serialize::Decoder> Decodable<D> for PackedFingerprint { #[inline] - fn decode(d: &mut D) -> Result<Self, D::Error> { - Fingerprint::decode(d).map(PackedFingerprint) + fn decode(d: &mut D) -> Self { + Self(Fingerprint::decode(d)) } } diff --git a/compiler/rustc_data_structures/src/svh.rs b/compiler/rustc_data_structures/src/svh.rs index ce90fbacaa4..12ef286091c 100644 --- a/compiler/rustc_data_structures/src/svh.rs +++ b/compiler/rustc_data_structures/src/svh.rs @@ -55,8 +55,8 @@ impl<S: Encoder> Encodable<S> for Svh { } impl<D: Decoder> Decodable<D> for Svh { - fn decode(d: &mut D) -> Result<Svh, D::Error> { - d.read_u64().map(u64::from_le).map(Svh::new) + fn decode(d: &mut D) -> Svh { + Svh::new(u64::from_le(d.read_u64())) } } diff --git a/compiler/rustc_driver/src/lib.rs b/compiler/rustc_driver/src/lib.rs index 19fa6812b45..2b64312dbef 100644 --- a/compiler/rustc_driver/src/lib.rs +++ b/compiler/rustc_driver/src/lib.rs @@ -597,10 +597,7 @@ impl RustcDefaultCalls { let rlink_data = fs::read_to_string(file).unwrap_or_else(|err| { sess.fatal(&format!("failed to read rlink file: {}", err)); }); - let codegen_results: CodegenResults = - json::decode(&rlink_data).unwrap_or_else(|err| { - sess.fatal(&format!("failed to decode rlink: {}", err)); - }); + let codegen_results: CodegenResults = json::decode(&rlink_data); let result = compiler.codegen_backend().link(sess, codegen_results, &outputs); abort_on_err(result, sess); } else { diff --git a/compiler/rustc_errors/src/json/tests.rs b/compiler/rustc_errors/src/json/tests.rs index d055937ac36..c5b3d204407 100644 --- a/compiler/rustc_errors/src/json/tests.rs +++ b/compiler/rustc_errors/src/json/tests.rs @@ -64,7 +64,7 @@ fn test_positions(code: &str, span: (u32, u32), expected_output: SpanTestData) { let bytes = output.lock().unwrap(); let actual_output = str::from_utf8(&bytes).unwrap(); - let actual_output: TestData = decode(actual_output).unwrap(); + let actual_output: TestData = decode(actual_output); assert_eq!(expected_output, actual_output) }) diff --git a/compiler/rustc_errors/src/lib.rs b/compiler/rustc_errors/src/lib.rs index a681298301a..dbacbba2ce0 100644 --- a/compiler/rustc_errors/src/lib.rs +++ b/compiler/rustc_errors/src/lib.rs @@ -99,8 +99,8 @@ impl Hash for ToolMetadata { // Doesn't really need to round-trip impl<D: Decoder> Decodable<D> for ToolMetadata { - fn decode(_d: &mut D) -> Result<Self, D::Error> { - Ok(ToolMetadata(None)) + fn decode(_d: &mut D) -> Self { + ToolMetadata(None) } } diff --git a/compiler/rustc_incremental/src/persist/load.rs b/compiler/rustc_incremental/src/persist/load.rs index d563a6ca478..870c3f80682 100644 --- a/compiler/rustc_incremental/src/persist/load.rs +++ b/compiler/rustc_incremental/src/persist/load.rs @@ -158,14 +158,7 @@ pub fn load_dep_graph(sess: &Session) -> DepGraphFuture { // Decode the list of work_products let mut work_product_decoder = Decoder::new(&work_products_data[..], start_pos); let work_products: Vec<SerializedWorkProduct> = - Decodable::decode(&mut work_product_decoder).unwrap_or_else(|e| { - let msg = format!( - "Error decoding `work-products` from incremental \ - compilation session directory: {}", - e - ); - sess.fatal(&msg) - }); + Decodable::decode(&mut work_product_decoder); for swp in work_products { let mut all_files_exist = true; @@ -203,8 +196,7 @@ pub fn load_dep_graph(sess: &Session) -> DepGraphFuture { LoadResult::Error { message } => LoadResult::Error { message }, LoadResult::Ok { data: (bytes, start_pos) } => { let mut decoder = Decoder::new(&bytes, start_pos); - let prev_commandline_args_hash = u64::decode(&mut decoder) - .expect("Error reading commandline arg hash from cached dep-graph"); + let prev_commandline_args_hash = u64::decode(&mut decoder); if prev_commandline_args_hash != expected_hash { if report_incremental_info { @@ -220,8 +212,7 @@ pub fn load_dep_graph(sess: &Session) -> DepGraphFuture { return LoadResult::DataOutOfDate; } - let dep_graph = SerializedDepGraph::decode(&mut decoder) - .expect("Error reading cached dep-graph"); + let dep_graph = SerializedDepGraph::decode(&mut decoder); LoadResult::Ok { data: (dep_graph, prev_work_products) } } diff --git a/compiler/rustc_index/src/vec.rs b/compiler/rustc_index/src/vec.rs index e3c6528b218..8b61530577d 100644 --- a/compiler/rustc_index/src/vec.rs +++ b/compiler/rustc_index/src/vec.rs @@ -395,8 +395,8 @@ macro_rules! newtype_index { (@serializable $type:ident) => ( impl<D: ::rustc_serialize::Decoder> ::rustc_serialize::Decodable<D> for $type { - fn decode(d: &mut D) -> Result<Self, D::Error> { - d.read_u32().map(Self::from_u32) + fn decode(d: &mut D) -> Self { + Self::from_u32(d.read_u32()) } } impl<E: ::rustc_serialize::Encoder> ::rustc_serialize::Encodable<E> for $type { @@ -527,8 +527,8 @@ impl<S: Encoder, I: Idx, T: Encodable<S>> Encodable<S> for &IndexVec<I, T> { } impl<D: Decoder, I: Idx, T: Decodable<D>> Decodable<D> for IndexVec<I, T> { - fn decode(d: &mut D) -> Result<Self, D::Error> { - Decodable::decode(d).map(|v| IndexVec { raw: v, _marker: PhantomData }) + fn decode(d: &mut D) -> Self { + IndexVec { raw: Decodable::decode(d), _marker: PhantomData } } } diff --git a/compiler/rustc_macros/src/serialize.rs b/compiler/rustc_macros/src/serialize.rs index 3351564299c..6c5461505fa 100644 --- a/compiler/rustc_macros/src/serialize.rs +++ b/compiler/rustc_macros/src/serialize.rs @@ -47,7 +47,7 @@ fn decodable_body( quote! { ::rustc_serialize::Decoder::read_struct( __decoder, - |__decoder| { ::std::result::Result::Ok(#construct) }, + |__decoder| { #construct }, ) } } @@ -57,7 +57,7 @@ fn decodable_body( .enumerate() .map(|(idx, vi)| { let construct = vi.construct(|field, index| decode_field(field, index, false)); - quote! { #idx => { ::std::result::Result::Ok(#construct) } } + quote! { #idx => { #construct } } }) .collect(); let names: TokenStream = variants @@ -82,8 +82,7 @@ fn decodable_body( |__decoder, __variant_idx| { match __variant_idx { #match_inner - _ => return ::std::result::Result::Err( - ::rustc_serialize::Decoder::error(__decoder, #message)), + _ => panic!(#message), } }) } @@ -95,9 +94,7 @@ fn decodable_body( s.bound_impl( quote!(::rustc_serialize::Decodable<#decoder_ty>), quote! { - fn decode( - __decoder: &mut #decoder_ty, - ) -> ::std::result::Result<Self, <#decoder_ty as ::rustc_serialize::Decoder>::Error> { + fn decode(__decoder: &mut #decoder_ty) -> Self { #decode_body } }, @@ -127,12 +124,7 @@ fn decode_field(field: &syn::Field, index: usize, is_struct: bool) -> proc_macro #__decoder, #opt_field_name #decode_inner_method) }; - quote! { - match #decode_call { - ::std::result::Result::Ok(__res) => __res, - ::std::result::Result::Err(__err) => return ::std::result::Result::Err(__err), - } - } + quote! { #decode_call } } pub fn type_encodable_derive(mut s: synstructure::Structure<'_>) -> proc_macro2::TokenStream { diff --git a/compiler/rustc_metadata/src/rmeta/decoder.rs b/compiler/rustc_metadata/src/rmeta/decoder.rs index 220bc9c5f75..5474d92072e 100644 --- a/compiler/rustc_metadata/src/rmeta/decoder.rs +++ b/compiler/rustc_metadata/src/rmeta/decoder.rs @@ -263,7 +263,7 @@ impl<'a, 'tcx, T: Decodable<DecodeContext<'a, 'tcx>>> Lazy<T> { fn decode<M: Metadata<'a, 'tcx>>(self, metadata: M) -> T { let mut dcx = metadata.decoder(self.position.get()); dcx.lazy_state = LazyState::NodeStart(self.position); - T::decode(&mut dcx).unwrap() + T::decode(&mut dcx) } } @@ -274,7 +274,7 @@ impl<'a: 'x, 'tcx: 'x, 'x, T: Decodable<DecodeContext<'a, 'tcx>>> Lazy<[T]> { ) -> impl ExactSizeIterator<Item = T> + Captures<'a> + Captures<'tcx> + 'x { let mut dcx = metadata.decoder(self.position.get()); dcx.lazy_state = LazyState::NodeStart(self.position); - (0..self.meta).map(move |_| T::decode(&mut dcx).unwrap()) + (0..self.meta).map(move |_| T::decode(&mut dcx)) } } @@ -300,11 +300,8 @@ impl<'a, 'tcx> DecodeContext<'a, 'tcx> { if cnum == LOCAL_CRATE { self.cdata().cnum } else { self.cdata().cnum_map[cnum] } } - fn read_lazy_with_meta<T: ?Sized + LazyMeta>( - &mut self, - meta: T::Meta, - ) -> Result<Lazy<T>, <Self as Decoder>::Error> { - let distance = self.read_usize()?; + fn read_lazy_with_meta<T: ?Sized + LazyMeta>(&mut self, meta: T::Meta) -> Lazy<T> { + let distance = self.read_usize(); let position = match self.lazy_state { LazyState::NoNode => bug!("read_lazy_with_meta: outside of a metadata node"), LazyState::NodeStart(start) => { @@ -315,7 +312,7 @@ impl<'a, 'tcx> DecodeContext<'a, 'tcx> { LazyState::Previous(last_pos) => last_pos.get() + distance, }; self.lazy_state = LazyState::Previous(NonZeroUsize::new(position).unwrap()); - Ok(Lazy::from_position_and_meta(NonZeroUsize::new(position).unwrap(), meta)) + Lazy::from_position_and_meta(NonZeroUsize::new(position).unwrap(), meta) } #[inline] @@ -342,25 +339,21 @@ impl<'a, 'tcx> TyDecoder<'tcx> for DecodeContext<'a, 'tcx> { self.opaque.position() } - fn cached_ty_for_shorthand<F>( - &mut self, - shorthand: usize, - or_insert_with: F, - ) -> Result<Ty<'tcx>, Self::Error> + fn cached_ty_for_shorthand<F>(&mut self, shorthand: usize, or_insert_with: F) -> Ty<'tcx> where - F: FnOnce(&mut Self) -> Result<Ty<'tcx>, Self::Error>, + F: FnOnce(&mut Self) -> Ty<'tcx>, { let tcx = self.tcx(); let key = ty::CReaderCacheKey { cnum: Some(self.cdata().cnum), pos: shorthand }; if let Some(&ty) = tcx.ty_rcache.borrow().get(&key) { - return Ok(ty); + return ty; } - let ty = or_insert_with(self)?; + let ty = or_insert_with(self); tcx.ty_rcache.borrow_mut().insert(key, ty); - Ok(ty) + ty } fn with_position<F, R>(&mut self, pos: usize, f: F) -> R @@ -376,7 +369,7 @@ impl<'a, 'tcx> TyDecoder<'tcx> for DecodeContext<'a, 'tcx> { r } - fn decode_alloc_id(&mut self) -> Result<rustc_middle::mir::interpret::AllocId, Self::Error> { + fn decode_alloc_id(&mut self) -> rustc_middle::mir::interpret::AllocId { if let Some(alloc_decoding_session) = self.alloc_decoding_session { alloc_decoding_session.decode_alloc_id(self) } else { @@ -386,48 +379,48 @@ impl<'a, 'tcx> TyDecoder<'tcx> for DecodeContext<'a, 'tcx> { } impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for CrateNum { - fn decode(d: &mut DecodeContext<'a, 'tcx>) -> Result<CrateNum, String> { - let cnum = CrateNum::from_u32(d.read_u32()?); - Ok(d.map_encoded_cnum_to_current(cnum)) + fn decode(d: &mut DecodeContext<'a, 'tcx>) -> CrateNum { + let cnum = CrateNum::from_u32(d.read_u32()); + d.map_encoded_cnum_to_current(cnum) } } impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for DefIndex { - fn decode(d: &mut DecodeContext<'a, 'tcx>) -> Result<DefIndex, String> { - Ok(DefIndex::from_u32(d.read_u32()?)) + fn decode(d: &mut DecodeContext<'a, 'tcx>) -> DefIndex { + DefIndex::from_u32(d.read_u32()) } } impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for ExpnIndex { - fn decode(d: &mut DecodeContext<'a, 'tcx>) -> Result<ExpnIndex, String> { - Ok(ExpnIndex::from_u32(d.read_u32()?)) + fn decode(d: &mut DecodeContext<'a, 'tcx>) -> ExpnIndex { + ExpnIndex::from_u32(d.read_u32()) } } impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for SyntaxContext { - fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Result<SyntaxContext, String> { + fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> SyntaxContext { let cdata = decoder.cdata(); let sess = decoder.sess.unwrap(); let cname = cdata.root.name; rustc_span::hygiene::decode_syntax_context(decoder, &cdata.hygiene_context, |_, id| { debug!("SpecializedDecoder<SyntaxContext>: decoding {}", id); - Ok(cdata + cdata .root .syntax_contexts .get(cdata, id) .unwrap_or_else(|| panic!("Missing SyntaxContext {:?} for crate {:?}", id, cname)) - .decode((cdata, sess))) + .decode((cdata, sess)) }) } } impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for ExpnId { - fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Result<ExpnId, String> { + fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> ExpnId { let local_cdata = decoder.cdata(); let sess = decoder.sess.unwrap(); - let cnum = CrateNum::decode(decoder)?; - let index = u32::decode(decoder)?; + let cnum = CrateNum::decode(decoder); + let index = u32::decode(decoder); let expn_id = rustc_span::hygiene::decode_expn_id(cnum, index, |expn_id| { let ExpnId { krate: cnum, local_id: index } = expn_id; @@ -453,23 +446,23 @@ impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for ExpnId { .decode((crate_data, sess)); (expn_data, expn_hash) }); - Ok(expn_id) + expn_id } } impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for Span { - fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Result<Span, String> { - let ctxt = SyntaxContext::decode(decoder)?; - let tag = u8::decode(decoder)?; + fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Span { + let ctxt = SyntaxContext::decode(decoder); + let tag = u8::decode(decoder); if tag == TAG_PARTIAL_SPAN { - return Ok(DUMMY_SP.with_ctxt(ctxt)); + return DUMMY_SP.with_ctxt(ctxt); } debug_assert!(tag == TAG_VALID_SPAN_LOCAL || tag == TAG_VALID_SPAN_FOREIGN); - let lo = BytePos::decode(decoder)?; - let len = BytePos::decode(decoder)?; + let lo = BytePos::decode(decoder); + let len = BytePos::decode(decoder); let hi = lo + len; let Some(sess) = decoder.sess else { @@ -512,7 +505,7 @@ impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for Span { if decoder.cdata().root.is_proc_macro_crate() { // Decode `CrateNum` as u32 - using `CrateNum::decode` will ICE // since we don't have `cnum_map` populated. - let cnum = u32::decode(decoder)?; + let cnum = u32::decode(decoder); panic!( "Decoding of crate {:?} tried to access proc-macro dep {:?}", decoder.cdata().root.name, @@ -520,7 +513,7 @@ impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for Span { ); } // tag is TAG_VALID_SPAN_FOREIGN, checked by `debug_assert` above - let cnum = CrateNum::decode(decoder)?; + let cnum = CrateNum::decode(decoder); debug!( "SpecializedDecoder<Span>::specialized_decode: loading source files from cnum {:?}", cnum @@ -582,18 +575,18 @@ impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for Span { (hi + source_file.translated_source_file.start_pos) - source_file.original_start_pos; // Do not try to decode parent for foreign spans. - Ok(Span::new(lo, hi, ctxt, None)) + Span::new(lo, hi, ctxt, None) } } impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for &'tcx [thir::abstract_const::Node<'tcx>] { - fn decode(d: &mut DecodeContext<'a, 'tcx>) -> Result<Self, String> { + fn decode(d: &mut DecodeContext<'a, 'tcx>) -> Self { ty::codec::RefDecodable::decode(d) } } impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for &'tcx [(ty::Predicate<'tcx>, Span)] { - fn decode(d: &mut DecodeContext<'a, 'tcx>) -> Result<Self, String> { + fn decode(d: &mut DecodeContext<'a, 'tcx>) -> Self { ty::codec::RefDecodable::decode(d) } } @@ -601,7 +594,7 @@ impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for &'tcx [(ty::Predicate<'tcx impl<'a, 'tcx, T: Decodable<DecodeContext<'a, 'tcx>>> Decodable<DecodeContext<'a, 'tcx>> for Lazy<T> { - fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Result<Self, String> { + fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Self { decoder.read_lazy_with_meta(()) } } @@ -609,9 +602,9 @@ impl<'a, 'tcx, T: Decodable<DecodeContext<'a, 'tcx>>> Decodable<DecodeContext<'a impl<'a, 'tcx, T: Decodable<DecodeContext<'a, 'tcx>>> Decodable<DecodeContext<'a, 'tcx>> for Lazy<[T]> { - fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Result<Self, String> { - let len = decoder.read_usize()?; - if len == 0 { Ok(Lazy::empty()) } else { decoder.read_lazy_with_meta(len) } + fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Self { + let len = decoder.read_usize(); + if len == 0 { Lazy::empty() } else { decoder.read_lazy_with_meta(len) } } } @@ -620,8 +613,8 @@ impl<'a, 'tcx, I: Idx, T: Decodable<DecodeContext<'a, 'tcx>>> Decodable<DecodeCo where Option<T>: FixedSizeEncoding, { - fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Result<Self, String> { - let len = decoder.read_usize()?; + fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Self { + let len = decoder.read_usize(); decoder.read_lazy_with_meta(len) } } diff --git a/compiler/rustc_metadata/src/rmeta/def_path_hash_map.rs b/compiler/rustc_metadata/src/rmeta/def_path_hash_map.rs index 054431169a2..d66f2b031a8 100644 --- a/compiler/rustc_metadata/src/rmeta/def_path_hash_map.rs +++ b/compiler/rustc_metadata/src/rmeta/def_path_hash_map.rs @@ -39,11 +39,11 @@ impl<'a, 'tcx> Encodable<EncodeContext<'a, 'tcx>> for DefPathHashMapRef<'tcx> { } impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for DefPathHashMapRef<'static> { - fn decode(d: &mut DecodeContext<'a, 'tcx>) -> Result<DefPathHashMapRef<'static>, String> { + fn decode(d: &mut DecodeContext<'a, 'tcx>) -> DefPathHashMapRef<'static> { // Import TyDecoder so we can access the DecodeContext::position() method use crate::rustc_middle::ty::codec::TyDecoder; - let len = d.read_usize()?; + let len = d.read_usize(); let pos = d.position(); let o = OwningRef::new(d.blob().clone()).map(|x| &x[pos..pos + len]); @@ -52,7 +52,9 @@ impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for DefPathHashMapRef<'static> // the method. We use read_raw_bytes() for that. let _ = d.read_raw_bytes(len); - let inner = odht::HashTable::from_raw_bytes(o).map_err(|e| format!("{}", e))?; - Ok(DefPathHashMapRef::OwnedFromMetadata(inner)) + let inner = odht::HashTable::from_raw_bytes(o).unwrap_or_else(|e| { + panic!("decode error: {}", e); + }); + DefPathHashMapRef::OwnedFromMetadata(inner) } } diff --git a/compiler/rustc_middle/src/mir/graph_cyclic_cache.rs b/compiler/rustc_middle/src/mir/graph_cyclic_cache.rs index 5f028975bd0..e2f3d6e078f 100644 --- a/compiler/rustc_middle/src/mir/graph_cyclic_cache.rs +++ b/compiler/rustc_middle/src/mir/graph_cyclic_cache.rs @@ -45,8 +45,9 @@ impl<S: serialize::Encoder> serialize::Encodable<S> for GraphIsCyclicCache { impl<D: serialize::Decoder> serialize::Decodable<D> for GraphIsCyclicCache { #[inline] - fn decode(d: &mut D) -> Result<Self, D::Error> { - serialize::Decodable::decode(d).map(|_v: ()| Self::new()) + fn decode(d: &mut D) -> Self { + let () = serialize::Decodable::decode(d); + Self::new() } } diff --git a/compiler/rustc_middle/src/mir/interpret/mod.rs b/compiler/rustc_middle/src/mir/interpret/mod.rs index b762a10da84..66f2c6e78a2 100644 --- a/compiler/rustc_middle/src/mir/interpret/mod.rs +++ b/compiler/rustc_middle/src/mir/interpret/mod.rs @@ -273,20 +273,20 @@ pub struct AllocDecodingSession<'s> { impl<'s> AllocDecodingSession<'s> { /// Decodes an `AllocId` in a thread-safe way. - pub fn decode_alloc_id<'tcx, D>(&self, decoder: &mut D) -> Result<AllocId, D::Error> + pub fn decode_alloc_id<'tcx, D>(&self, decoder: &mut D) -> AllocId where D: TyDecoder<'tcx>, { // Read the index of the allocation. - let idx = usize::try_from(decoder.read_u32()?).unwrap(); + let idx = usize::try_from(decoder.read_u32()).unwrap(); let pos = usize::try_from(self.state.data_offsets[idx]).unwrap(); // Decode the `AllocDiscriminant` now so that we know if we have to reserve an // `AllocId`. let (alloc_kind, pos) = decoder.with_position(pos, |decoder| { - let alloc_kind = AllocDiscriminant::decode(decoder)?; - Ok((alloc_kind, decoder.position())) - })?; + let alloc_kind = AllocDiscriminant::decode(decoder); + (alloc_kind, decoder.position()) + }); // Check the decoding state to see if it's already decoded or if we should // decode it here. @@ -295,7 +295,7 @@ impl<'s> AllocDecodingSession<'s> { match *entry { State::Done(alloc_id) => { - return Ok(alloc_id); + return alloc_id; } ref mut entry @ State::Empty => { // We are allowed to decode. @@ -329,7 +329,7 @@ impl<'s> AllocDecodingSession<'s> { State::InProgress(ref mut sessions, alloc_id) => { if sessions.contains(&self.session_id) { // Don't recurse. - return Ok(alloc_id); + return alloc_id; } else { // Start decoding concurrently. sessions.insert(self.session_id); @@ -343,37 +343,37 @@ impl<'s> AllocDecodingSession<'s> { let alloc_id = decoder.with_position(pos, |decoder| { match alloc_kind { AllocDiscriminant::Alloc => { - let alloc = <&'tcx Allocation as Decodable<_>>::decode(decoder)?; + let alloc = <&'tcx Allocation as Decodable<_>>::decode(decoder); // We already have a reserved `AllocId`. let alloc_id = alloc_id.unwrap(); trace!("decoded alloc {:?}: {:#?}", alloc_id, alloc); decoder.tcx().set_alloc_id_same_memory(alloc_id, alloc); - Ok(alloc_id) + alloc_id } AllocDiscriminant::Fn => { assert!(alloc_id.is_none()); trace!("creating fn alloc ID"); - let instance = ty::Instance::decode(decoder)?; + let instance = ty::Instance::decode(decoder); trace!("decoded fn alloc instance: {:?}", instance); let alloc_id = decoder.tcx().create_fn_alloc(instance); - Ok(alloc_id) + alloc_id } AllocDiscriminant::Static => { assert!(alloc_id.is_none()); trace!("creating extern static alloc ID"); - let did = <DefId as Decodable<D>>::decode(decoder)?; + let did = <DefId as Decodable<D>>::decode(decoder); trace!("decoded static def-ID: {:?}", did); let alloc_id = decoder.tcx().create_static_alloc(did); - Ok(alloc_id) + alloc_id } } - })?; + }); self.state.decoding_state[idx].with_lock(|entry| { *entry = State::Done(alloc_id); }); - Ok(alloc_id) + alloc_id } } diff --git a/compiler/rustc_middle/src/mir/mod.rs b/compiler/rustc_middle/src/mir/mod.rs index 48f39b26152..c7b1e25b993 100644 --- a/compiler/rustc_middle/src/mir/mod.rs +++ b/compiler/rustc_middle/src/mir/mod.rs @@ -619,20 +619,20 @@ impl<'tcx, E: TyEncoder<'tcx>, T: Encodable<E>> Encodable<E> for ClearCrossCrate } impl<'tcx, D: TyDecoder<'tcx>, T: Decodable<D>> Decodable<D> for ClearCrossCrate<T> { #[inline] - fn decode(d: &mut D) -> Result<ClearCrossCrate<T>, D::Error> { + fn decode(d: &mut D) -> ClearCrossCrate<T> { if D::CLEAR_CROSS_CRATE { - return Ok(ClearCrossCrate::Clear); + return ClearCrossCrate::Clear; } - let discr = u8::decode(d)?; + let discr = u8::decode(d); match discr { - TAG_CLEAR_CROSS_CRATE_CLEAR => Ok(ClearCrossCrate::Clear), + TAG_CLEAR_CROSS_CRATE_CLEAR => ClearCrossCrate::Clear, TAG_CLEAR_CROSS_CRATE_SET => { - let val = T::decode(d)?; - Ok(ClearCrossCrate::Set(val)) + let val = T::decode(d); + ClearCrossCrate::Set(val) } - tag => Err(d.error(&format!("Invalid tag for ClearCrossCrate: {:?}", tag))), + tag => panic!("Invalid tag for ClearCrossCrate: {:?}", tag), } } } diff --git a/compiler/rustc_middle/src/mir/predecessors.rs b/compiler/rustc_middle/src/mir/predecessors.rs index fd6bb76dc43..2562baac911 100644 --- a/compiler/rustc_middle/src/mir/predecessors.rs +++ b/compiler/rustc_middle/src/mir/predecessors.rs @@ -57,14 +57,15 @@ impl PredecessorCache { impl<S: serialize::Encoder> serialize::Encodable<S> for PredecessorCache { #[inline] fn encode(&self, s: &mut S) -> Result<(), S::Error> { - serialize::Encodable::encode(&(), s) + s.emit_unit() } } impl<D: serialize::Decoder> serialize::Decodable<D> for PredecessorCache { #[inline] - fn decode(d: &mut D) -> Result<Self, D::Error> { - serialize::Decodable::decode(d).map(|_v: ()| Self::new()) + fn decode(d: &mut D) -> Self { + let () = d.read_unit(); + Self::new() } } diff --git a/compiler/rustc_middle/src/ty/codec.rs b/compiler/rustc_middle/src/ty/codec.rs index eb46cdac1da..4cd3b5e7a50 100644 --- a/compiler/rustc_middle/src/ty/codec.rs +++ b/compiler/rustc_middle/src/ty/codec.rs @@ -14,7 +14,7 @@ use crate::mir::{ }; use crate::thir; use crate::ty::subst::SubstsRef; -use crate::ty::{self, List, Ty, TyCtxt}; +use crate::ty::{self, Ty, TyCtxt}; use rustc_data_structures::fx::FxHashMap; use rustc_serialize::{Decodable, Decoder, Encodable, Encoder}; use rustc_span::Span; @@ -71,7 +71,7 @@ pub trait TyEncoder<'tcx>: Encoder { /// `Decodable` can still be implemented in cases where `Decodable` is required /// by a trait bound. pub trait RefDecodable<'tcx, D: TyDecoder<'tcx>> { - fn decode(d: &mut D) -> Result<&'tcx Self, D::Error>; + fn decode(d: &mut D) -> &'tcx Self; } /// Encode the given value or a previously cached shorthand. @@ -172,13 +172,9 @@ pub trait TyDecoder<'tcx>: Decoder { fn position(&self) -> usize; - fn cached_ty_for_shorthand<F>( - &mut self, - shorthand: usize, - or_insert_with: F, - ) -> Result<Ty<'tcx>, Self::Error> + fn cached_ty_for_shorthand<F>(&mut self, shorthand: usize, or_insert_with: F) -> Ty<'tcx> where - F: FnOnce(&mut Self) -> Result<Ty<'tcx>, Self::Error>; + F: FnOnce(&mut Self) -> Ty<'tcx>; fn with_position<F, R>(&mut self, pos: usize, f: F) -> R where @@ -188,35 +184,35 @@ pub trait TyDecoder<'tcx>: Decoder { (self.peek_byte() & (SHORTHAND_OFFSET as u8)) != 0 } - fn decode_alloc_id(&mut self) -> Result<AllocId, Self::Error>; + fn decode_alloc_id(&mut self) -> AllocId; } #[inline] fn decode_arena_allocable<'tcx, D, T: ArenaAllocatable<'tcx> + Decodable<D>>( decoder: &mut D, -) -> Result<&'tcx T, D::Error> +) -> &'tcx T where D: TyDecoder<'tcx>, { - Ok(decoder.tcx().arena.alloc(Decodable::decode(decoder)?)) + decoder.tcx().arena.alloc(Decodable::decode(decoder)) } #[inline] fn decode_arena_allocable_slice<'tcx, D, T: ArenaAllocatable<'tcx> + Decodable<D>>( decoder: &mut D, -) -> Result<&'tcx [T], D::Error> +) -> &'tcx [T] where D: TyDecoder<'tcx>, { - Ok(decoder.tcx().arena.alloc_from_iter(<Vec<T> as Decodable<D>>::decode(decoder)?)) + decoder.tcx().arena.alloc_from_iter(<Vec<T> as Decodable<D>>::decode(decoder)) } impl<'tcx, D: TyDecoder<'tcx>> Decodable<D> for Ty<'tcx> { #[allow(rustc::usage_of_ty_tykind)] - fn decode(decoder: &mut D) -> Result<Ty<'tcx>, D::Error> { + fn decode(decoder: &mut D) -> Ty<'tcx> { // Handle shorthands first, if we have a usize > 0x80. if decoder.positioned_at_shorthand() { - let pos = decoder.read_usize()?; + let pos = decoder.read_usize(); assert!(pos >= SHORTHAND_OFFSET); let shorthand = pos - SHORTHAND_OFFSET; @@ -225,87 +221,89 @@ impl<'tcx, D: TyDecoder<'tcx>> Decodable<D> for Ty<'tcx> { }) } else { let tcx = decoder.tcx(); - Ok(tcx.mk_ty(ty::TyKind::decode(decoder)?)) + tcx.mk_ty(ty::TyKind::decode(decoder)) } } } impl<'tcx, D: TyDecoder<'tcx>> Decodable<D> for ty::Binder<'tcx, ty::PredicateKind<'tcx>> { - fn decode(decoder: &mut D) -> Result<ty::Binder<'tcx, ty::PredicateKind<'tcx>>, D::Error> { - let bound_vars = Decodable::decode(decoder)?; + fn decode(decoder: &mut D) -> ty::Binder<'tcx, ty::PredicateKind<'tcx>> { + let bound_vars = Decodable::decode(decoder); // Handle shorthands first, if we have a usize > 0x80. - Ok(ty::Binder::bind_with_vars( + ty::Binder::bind_with_vars( if decoder.positioned_at_shorthand() { - let pos = decoder.read_usize()?; + let pos = decoder.read_usize(); assert!(pos >= SHORTHAND_OFFSET); let shorthand = pos - SHORTHAND_OFFSET; - decoder.with_position(shorthand, ty::PredicateKind::decode)? + decoder.with_position(shorthand, ty::PredicateKind::decode) } else { - ty::PredicateKind::decode(decoder)? + ty::PredicateKind::decode(decoder) }, bound_vars, - )) + ) } } impl<'tcx, D: TyDecoder<'tcx>> Decodable<D> for ty::Predicate<'tcx> { - fn decode(decoder: &mut D) -> Result<ty::Predicate<'tcx>, D::Error> { - let predicate_kind = Decodable::decode(decoder)?; - let predicate = decoder.tcx().mk_predicate(predicate_kind); - Ok(predicate) + fn decode(decoder: &mut D) -> ty::Predicate<'tcx> { + let predicate_kind = Decodable::decode(decoder); + decoder.tcx().mk_predicate(predicate_kind) } } impl<'tcx, D: TyDecoder<'tcx>> Decodable<D> for SubstsRef<'tcx> { - fn decode(decoder: &mut D) -> Result<Self, D::Error> { - let len = decoder.read_usize()?; + fn decode(decoder: &mut D) -> Self { + let len = decoder.read_usize(); let tcx = decoder.tcx(); - tcx.mk_substs((0..len).map(|_| Decodable::decode(decoder))) + tcx.mk_substs( + (0..len).map::<ty::subst::GenericArg<'tcx>, _>(|_| Decodable::decode(decoder)), + ) } } impl<'tcx, D: TyDecoder<'tcx>> Decodable<D> for mir::Place<'tcx> { - fn decode(decoder: &mut D) -> Result<Self, D::Error> { - let local: mir::Local = Decodable::decode(decoder)?; - let len = decoder.read_usize()?; - let projection: &'tcx List<mir::PlaceElem<'tcx>> = - decoder.tcx().mk_place_elems((0..len).map(|_| Decodable::decode(decoder)))?; - Ok(mir::Place { local, projection }) + fn decode(decoder: &mut D) -> Self { + let local: mir::Local = Decodable::decode(decoder); + let len = decoder.read_usize(); + let projection = decoder.tcx().mk_place_elems( + (0..len).map::<mir::PlaceElem<'tcx>, _>(|_| Decodable::decode(decoder)), + ); + mir::Place { local, projection } } } impl<'tcx, D: TyDecoder<'tcx>> Decodable<D> for ty::Region<'tcx> { - fn decode(decoder: &mut D) -> Result<Self, D::Error> { - Ok(decoder.tcx().mk_region(Decodable::decode(decoder)?)) + fn decode(decoder: &mut D) -> Self { + decoder.tcx().mk_region(Decodable::decode(decoder)) } } impl<'tcx, D: TyDecoder<'tcx>> Decodable<D> for CanonicalVarInfos<'tcx> { - fn decode(decoder: &mut D) -> Result<Self, D::Error> { - let len = decoder.read_usize()?; - let interned: Result<Vec<CanonicalVarInfo<'tcx>>, _> = + fn decode(decoder: &mut D) -> Self { + let len = decoder.read_usize(); + let interned: Vec<CanonicalVarInfo<'tcx>> = (0..len).map(|_| Decodable::decode(decoder)).collect(); - Ok(decoder.tcx().intern_canonical_var_infos(interned?.as_slice())) + decoder.tcx().intern_canonical_var_infos(interned.as_slice()) } } impl<'tcx, D: TyDecoder<'tcx>> Decodable<D> for AllocId { - fn decode(decoder: &mut D) -> Result<Self, D::Error> { + fn decode(decoder: &mut D) -> Self { decoder.decode_alloc_id() } } impl<'tcx, D: TyDecoder<'tcx>> Decodable<D> for ty::SymbolName<'tcx> { - fn decode(decoder: &mut D) -> Result<Self, D::Error> { - Ok(ty::SymbolName::new(decoder.tcx(), &decoder.read_str()?)) + fn decode(decoder: &mut D) -> Self { + ty::SymbolName::new(decoder.tcx(), &decoder.read_str()) } } macro_rules! impl_decodable_via_ref { ($($t:ty),+) => { $(impl<'tcx, D: TyDecoder<'tcx>> Decodable<D> for $t { - fn decode(decoder: &mut D) -> Result<Self, D::Error> { + fn decode(decoder: &mut D) -> Self { RefDecodable::decode(decoder) } })* @@ -313,77 +311,73 @@ macro_rules! impl_decodable_via_ref { } impl<'tcx, D: TyDecoder<'tcx>> RefDecodable<'tcx, D> for ty::List<Ty<'tcx>> { - fn decode(decoder: &mut D) -> Result<&'tcx Self, D::Error> { - let len = decoder.read_usize()?; - decoder.tcx().mk_type_list((0..len).map(|_| Decodable::decode(decoder))) + fn decode(decoder: &mut D) -> &'tcx Self { + let len = decoder.read_usize(); + decoder.tcx().mk_type_list((0..len).map::<Ty<'tcx>, _>(|_| Decodable::decode(decoder))) } } impl<'tcx, D: TyDecoder<'tcx>> RefDecodable<'tcx, D> for ty::List<ty::Binder<'tcx, ty::ExistentialPredicate<'tcx>>> { - fn decode(decoder: &mut D) -> Result<&'tcx Self, D::Error> { - let len = decoder.read_usize()?; - decoder.tcx().mk_poly_existential_predicates((0..len).map(|_| Decodable::decode(decoder))) + fn decode(decoder: &mut D) -> &'tcx Self { + let len = decoder.read_usize(); + decoder.tcx().mk_poly_existential_predicates( + (0..len).map::<ty::Binder<'tcx, _>, _>(|_| Decodable::decode(decoder)), + ) } } impl<'tcx, D: TyDecoder<'tcx>> RefDecodable<'tcx, D> for ty::Const<'tcx> { - fn decode(decoder: &mut D) -> Result<&'tcx Self, D::Error> { - Ok(decoder.tcx().mk_const(Decodable::decode(decoder)?)) + fn decode(decoder: &mut D) -> &'tcx Self { + decoder.tcx().mk_const(Decodable::decode(decoder)) } } impl<'tcx, D: TyDecoder<'tcx>> RefDecodable<'tcx, D> for [ty::ValTree<'tcx>] { - fn decode(decoder: &mut D) -> Result<&'tcx Self, D::Error> { - Ok(decoder.tcx().arena.alloc_from_iter( - (0..decoder.read_usize()?) - .map(|_| Decodable::decode(decoder)) - .collect::<Result<Vec<_>, _>>()?, - )) + fn decode(decoder: &mut D) -> &'tcx Self { + decoder.tcx().arena.alloc_from_iter( + (0..decoder.read_usize()).map(|_| Decodable::decode(decoder)).collect::<Vec<_>>(), + ) } } impl<'tcx, D: TyDecoder<'tcx>> RefDecodable<'tcx, D> for Allocation { - fn decode(decoder: &mut D) -> Result<&'tcx Self, D::Error> { - Ok(decoder.tcx().intern_const_alloc(Decodable::decode(decoder)?)) + fn decode(decoder: &mut D) -> &'tcx Self { + decoder.tcx().intern_const_alloc(Decodable::decode(decoder)) } } impl<'tcx, D: TyDecoder<'tcx>> RefDecodable<'tcx, D> for [(ty::Predicate<'tcx>, Span)] { - fn decode(decoder: &mut D) -> Result<&'tcx Self, D::Error> { - Ok(decoder.tcx().arena.alloc_from_iter( - (0..decoder.read_usize()?) - .map(|_| Decodable::decode(decoder)) - .collect::<Result<Vec<_>, _>>()?, - )) + fn decode(decoder: &mut D) -> &'tcx Self { + decoder.tcx().arena.alloc_from_iter( + (0..decoder.read_usize()).map(|_| Decodable::decode(decoder)).collect::<Vec<_>>(), + ) } } impl<'tcx, D: TyDecoder<'tcx>> RefDecodable<'tcx, D> for [thir::abstract_const::Node<'tcx>] { - fn decode(decoder: &mut D) -> Result<&'tcx Self, D::Error> { - Ok(decoder.tcx().arena.alloc_from_iter( - (0..decoder.read_usize()?) - .map(|_| Decodable::decode(decoder)) - .collect::<Result<Vec<_>, _>>()?, - )) + fn decode(decoder: &mut D) -> &'tcx Self { + decoder.tcx().arena.alloc_from_iter( + (0..decoder.read_usize()).map(|_| Decodable::decode(decoder)).collect::<Vec<_>>(), + ) } } impl<'tcx, D: TyDecoder<'tcx>> RefDecodable<'tcx, D> for [thir::abstract_const::NodeId] { - fn decode(decoder: &mut D) -> Result<&'tcx Self, D::Error> { - Ok(decoder.tcx().arena.alloc_from_iter( - (0..decoder.read_usize()?) - .map(|_| Decodable::decode(decoder)) - .collect::<Result<Vec<_>, _>>()?, - )) + fn decode(decoder: &mut D) -> &'tcx Self { + decoder.tcx().arena.alloc_from_iter( + (0..decoder.read_usize()).map(|_| Decodable::decode(decoder)).collect::<Vec<_>>(), + ) } } impl<'tcx, D: TyDecoder<'tcx>> RefDecodable<'tcx, D> for ty::List<ty::BoundVariableKind> { - fn decode(decoder: &mut D) -> Result<&'tcx Self, D::Error> { - let len = decoder.read_usize()?; - decoder.tcx().mk_bound_variable_kinds((0..len).map(|_| Decodable::decode(decoder))) + fn decode(decoder: &mut D) -> &'tcx Self { + let len = decoder.read_usize(); + decoder.tcx().mk_bound_variable_kinds( + (0..len).map::<ty::BoundVariableKind, _>(|_| Decodable::decode(decoder)), + ) } } @@ -405,7 +399,7 @@ macro_rules! __impl_decoder_methods { ($($name:ident -> $ty:ty;)*) => { $( #[inline] - fn $name(&mut self) -> Result<$ty, Self::Error> { + fn $name(&mut self) -> $ty { self.opaque.$name() } )* @@ -418,14 +412,14 @@ macro_rules! impl_arena_allocatable_decoder { [$name:ident: $ty:ty]) => { impl<'tcx, D: TyDecoder<'tcx>> RefDecodable<'tcx, D> for $ty { #[inline] - fn decode(decoder: &mut D) -> Result<&'tcx Self, D::Error> { + fn decode(decoder: &mut D) -> &'tcx Self { decode_arena_allocable(decoder) } } impl<'tcx, D: TyDecoder<'tcx>> RefDecodable<'tcx, D> for [$ty] { #[inline] - fn decode(decoder: &mut D) -> Result<&'tcx Self, D::Error> { + fn decode(decoder: &mut D) -> &'tcx Self { decode_arena_allocable_slice(decoder) } } @@ -456,8 +450,6 @@ macro_rules! implement_ty_decoder { use super::$DecoderName; impl<$($typaram ),*> Decoder for $DecoderName<$($typaram),*> { - type Error = String; - $crate::__impl_decoder_methods! { read_unit -> (); @@ -483,13 +475,9 @@ macro_rules! implement_ty_decoder { } #[inline] - fn read_raw_bytes_into(&mut self, bytes: &mut [u8]) -> Result<(), Self::Error> { + fn read_raw_bytes_into(&mut self, bytes: &mut [u8]) -> () { self.opaque.read_raw_bytes_into(bytes) } - - fn error(&mut self, err: &str) -> Self::Error { - self.opaque.error(err) - } } } } @@ -505,9 +493,9 @@ macro_rules! impl_binder_encode_decode { } } impl<'tcx, D: TyDecoder<'tcx>> Decodable<D> for ty::Binder<'tcx, $t> { - fn decode(decoder: &mut D) -> Result<Self, D::Error> { - let bound_vars = Decodable::decode(decoder)?; - Ok(ty::Binder::bind_with_vars(Decodable::decode(decoder)?, bound_vars)) + fn decode(decoder: &mut D) -> Self { + let bound_vars = Decodable::decode(decoder); + ty::Binder::bind_with_vars(Decodable::decode(decoder), bound_vars) } } )* diff --git a/compiler/rustc_middle/src/ty/consts/int.rs b/compiler/rustc_middle/src/ty/consts/int.rs index 1f4ebd03676..de45e1bb851 100644 --- a/compiler/rustc_middle/src/ty/consts/int.rs +++ b/compiler/rustc_middle/src/ty/consts/int.rs @@ -147,8 +147,8 @@ impl<S: Encoder> Encodable<S> for ScalarInt { } impl<D: Decoder> Decodable<D> for ScalarInt { - fn decode(d: &mut D) -> Result<ScalarInt, D::Error> { - Ok(ScalarInt { data: d.read_u128()?, size: d.read_u8()? }) + fn decode(d: &mut D) -> ScalarInt { + ScalarInt { data: d.read_u128(), size: d.read_u8() } } } diff --git a/compiler/rustc_middle/src/ty/context.rs b/compiler/rustc_middle/src/ty/context.rs index a7d7ee5efc8..acc115e48a4 100644 --- a/compiler/rustc_middle/src/ty/context.rs +++ b/compiler/rustc_middle/src/ty/context.rs @@ -2786,8 +2786,33 @@ pub trait InternIteratorElement<T, R>: Sized { impl<T, R> InternIteratorElement<T, R> for T { type Output = R; - fn intern_with<I: Iterator<Item = Self>, F: FnOnce(&[T]) -> R>(iter: I, f: F) -> Self::Output { - f(&iter.collect::<SmallVec<[_; 8]>>()) + fn intern_with<I: Iterator<Item = Self>, F: FnOnce(&[T]) -> R>( + mut iter: I, + f: F, + ) -> Self::Output { + // This code is hot enough that it's worth specializing for the most + // common length lists, to avoid the overhead of `SmallVec` creation. + // Lengths 0, 1, and 2 typically account for ~95% of cases. We assume + // that if the upper and lower bounds from `size_hint` agree they are + // correct. + match iter.size_hint() { + (0, Some(0)) => { + assert!(iter.next().is_none()); + f(&[]) + } + (1, Some(1)) => { + let t0 = iter.next().unwrap(); + assert!(iter.next().is_none()); + f(&[t0]) + } + (2, Some(2)) => { + let t0 = iter.next().unwrap(); + let t1 = iter.next().unwrap(); + assert!(iter.next().is_none()); + f(&[t0, t1]) + } + _ => f(&iter.collect::<SmallVec<[_; 8]>>()), + } } } @@ -2797,6 +2822,7 @@ where { type Output = R; fn intern_with<I: Iterator<Item = Self>, F: FnOnce(&[T]) -> R>(iter: I, f: F) -> Self::Output { + // This code isn't hot. f(&iter.cloned().collect::<SmallVec<[_; 8]>>()) } } @@ -2809,10 +2835,14 @@ impl<T, R, E> InternIteratorElement<T, R> for Result<T, E> { ) -> Self::Output { // This code is hot enough that it's worth specializing for the most // common length lists, to avoid the overhead of `SmallVec` creation. - // The match arms are in order of frequency. The 1, 2, and 0 cases are - // typically hit in ~95% of cases. We assume that if the upper and - // lower bounds from `size_hint` agree they are correct. + // Lengths 0, 1, and 2 typically account for ~95% of cases. We assume + // that if the upper and lower bounds from `size_hint` agree they are + // correct. Ok(match iter.size_hint() { + (0, Some(0)) => { + assert!(iter.next().is_none()); + f(&[]) + } (1, Some(1)) => { let t0 = iter.next().unwrap()?; assert!(iter.next().is_none()); @@ -2824,10 +2854,6 @@ impl<T, R, E> InternIteratorElement<T, R> for Result<T, E> { assert!(iter.next().is_none()); f(&[t0, t1]) } - (0, Some(0)) => { - assert!(iter.next().is_none()); - f(&[]) - } _ => f(&iter.collect::<Result<SmallVec<[_; 8]>, _>>()?), }) } diff --git a/compiler/rustc_middle/src/ty/subst.rs b/compiler/rustc_middle/src/ty/subst.rs index 63e9b58584c..cf97344f18e 100644 --- a/compiler/rustc_middle/src/ty/subst.rs +++ b/compiler/rustc_middle/src/ty/subst.rs @@ -180,8 +180,8 @@ impl<'tcx, E: TyEncoder<'tcx>> Encodable<E> for GenericArg<'tcx> { } impl<'tcx, D: TyDecoder<'tcx>> Decodable<D> for GenericArg<'tcx> { - fn decode(d: &mut D) -> Result<GenericArg<'tcx>, D::Error> { - Ok(GenericArgKind::decode(d)?.pack()) + fn decode(d: &mut D) -> GenericArg<'tcx> { + GenericArgKind::decode(d).pack() } } diff --git a/compiler/rustc_query_impl/src/on_disk_cache.rs b/compiler/rustc_query_impl/src/on_disk_cache.rs index 5f6d9b050b2..06e276ab42b 100644 --- a/compiler/rustc_query_impl/src/on_disk_cache.rs +++ b/compiler/rustc_query_impl/src/on_disk_cache.rs @@ -163,15 +163,12 @@ impl<'sess> rustc_middle::ty::OnDiskCache<'sess> for OnDiskCache<'sess> { // Decode the *position* of the footer, which can be found in the // last 8 bytes of the file. decoder.set_position(data.len() - IntEncodedWithFixedSize::ENCODED_SIZE); - let footer_pos = IntEncodedWithFixedSize::decode(&mut decoder) - .expect("error while trying to decode footer position") - .0 as usize; + let footer_pos = IntEncodedWithFixedSize::decode(&mut decoder).0 as usize; // Decode the file footer, which contains all the lookup tables, etc. decoder.set_position(footer_pos); decode_tagged(&mut decoder, TAG_FILE_FOOTER) - .expect("error while trying to decode footer position") }; Self { @@ -372,7 +369,7 @@ impl<'sess> OnDiskCache<'sess> { dep_node_index: SerializedDepNodeIndex, ) -> QuerySideEffects { let side_effects: Option<QuerySideEffects> = - self.load_indexed(tcx, dep_node_index, &self.prev_side_effects_index, "side_effects"); + self.load_indexed(tcx, dep_node_index, &self.prev_side_effects_index); side_effects.unwrap_or_default() } @@ -398,7 +395,7 @@ impl<'sess> OnDiskCache<'sess> { where T: for<'a> Decodable<CacheDecoder<'a, 'tcx>>, { - self.load_indexed(tcx, dep_node_index, &self.query_result_index, "query result") + self.load_indexed(tcx, dep_node_index, &self.query_result_index) } /// Stores side effect emitted during computation of an anonymous query. @@ -423,17 +420,13 @@ impl<'sess> OnDiskCache<'sess> { tcx: TyCtxt<'tcx>, dep_node_index: SerializedDepNodeIndex, index: &FxHashMap<SerializedDepNodeIndex, AbsoluteBytePos>, - debug_tag: &'static str, ) -> Option<T> where T: for<'a> Decodable<CacheDecoder<'a, 'tcx>>, { let pos = index.get(&dep_node_index).cloned()?; - self.with_decoder(tcx, pos, |decoder| match decode_tagged(decoder, dep_node_index) { - Ok(v) => Some(v), - Err(e) => bug!("could not decode cached {}: {}", debug_tag, e), - }) + self.with_decoder(tcx, pos, |decoder| Some(decode_tagged(decoder, dep_node_index))) } fn with_decoder<'a, 'tcx, T, F: for<'s> FnOnce(&mut CacheDecoder<'s, 'tcx>) -> T>( @@ -535,7 +528,7 @@ impl<'a, 'tcx> DecoderWithPosition for CacheDecoder<'a, 'tcx> { // Decodes something that was encoded with `encode_tagged()` and verify that the // tag matches and the correct amount of bytes was read. -fn decode_tagged<D, T, V>(decoder: &mut D, expected_tag: T) -> Result<V, D::Error> +fn decode_tagged<D, T, V>(decoder: &mut D, expected_tag: T) -> V where T: Decodable<D> + Eq + std::fmt::Debug, V: Decodable<D>, @@ -543,15 +536,15 @@ where { let start_pos = decoder.position(); - let actual_tag = T::decode(decoder)?; + let actual_tag = T::decode(decoder); assert_eq!(actual_tag, expected_tag); - let value = V::decode(decoder)?; + let value = V::decode(decoder); let end_pos = decoder.position(); - let expected_len: u64 = Decodable::decode(decoder)?; + let expected_len: u64 = Decodable::decode(decoder); assert_eq!((end_pos - start_pos) as u64, expected_len); - Ok(value) + value } impl<'a, 'tcx> TyDecoder<'tcx> for CacheDecoder<'a, 'tcx> { @@ -572,26 +565,22 @@ impl<'a, 'tcx> TyDecoder<'tcx> for CacheDecoder<'a, 'tcx> { self.opaque.data[self.opaque.position()] } - fn cached_ty_for_shorthand<F>( - &mut self, - shorthand: usize, - or_insert_with: F, - ) -> Result<Ty<'tcx>, Self::Error> + fn cached_ty_for_shorthand<F>(&mut self, shorthand: usize, or_insert_with: F) -> Ty<'tcx> where - F: FnOnce(&mut Self) -> Result<Ty<'tcx>, Self::Error>, + F: FnOnce(&mut Self) -> Ty<'tcx>, { let tcx = self.tcx(); let cache_key = ty::CReaderCacheKey { cnum: None, pos: shorthand }; if let Some(&ty) = tcx.ty_rcache.borrow().get(&cache_key) { - return Ok(ty); + return ty; } - let ty = or_insert_with(self)?; + let ty = or_insert_with(self); // This may overwrite the entry, but it should overwrite with the same value. tcx.ty_rcache.borrow_mut().insert_same(cache_key, ty); - Ok(ty) + ty } fn with_position<F, R>(&mut self, pos: usize, f: F) -> R @@ -607,7 +596,7 @@ impl<'a, 'tcx> TyDecoder<'tcx> for CacheDecoder<'a, 'tcx> { r } - fn decode_alloc_id(&mut self) -> Result<interpret::AllocId, Self::Error> { + fn decode_alloc_id(&mut self) -> interpret::AllocId { let alloc_decoding_session = self.alloc_decoding_session; alloc_decoding_session.decode_alloc_id(self) } @@ -619,35 +608,35 @@ rustc_middle::implement_ty_decoder!(CacheDecoder<'a, 'tcx>); // when a `CacheDecoder` is passed to `Decodable::decode`. Unfortunately, we have to manually opt // into specializations this way, given how `CacheDecoder` and the decoding traits currently work. impl<'a, 'tcx> Decodable<CacheDecoder<'a, 'tcx>> for Vec<u8> { - fn decode(d: &mut CacheDecoder<'a, 'tcx>) -> Result<Self, String> { + fn decode(d: &mut CacheDecoder<'a, 'tcx>) -> Self { Decodable::decode(&mut d.opaque) } } impl<'a, 'tcx> Decodable<CacheDecoder<'a, 'tcx>> for SyntaxContext { - fn decode(decoder: &mut CacheDecoder<'a, 'tcx>) -> Result<Self, String> { + fn decode(decoder: &mut CacheDecoder<'a, 'tcx>) -> Self { let syntax_contexts = decoder.syntax_contexts; rustc_span::hygiene::decode_syntax_context(decoder, decoder.hygiene_context, |this, id| { // This closure is invoked if we haven't already decoded the data for the `SyntaxContext` we are deserializing. // We look up the position of the associated `SyntaxData` and decode it. let pos = syntax_contexts.get(&id).unwrap(); this.with_position(pos.to_usize(), |decoder| { - let data: SyntaxContextData = decode_tagged(decoder, TAG_SYNTAX_CONTEXT)?; - Ok(data) + let data: SyntaxContextData = decode_tagged(decoder, TAG_SYNTAX_CONTEXT); + data }) }) } } impl<'a, 'tcx> Decodable<CacheDecoder<'a, 'tcx>> for ExpnId { - fn decode(decoder: &mut CacheDecoder<'a, 'tcx>) -> Result<Self, String> { - let hash = ExpnHash::decode(decoder)?; + fn decode(decoder: &mut CacheDecoder<'a, 'tcx>) -> Self { + let hash = ExpnHash::decode(decoder); if hash.is_root() { - return Ok(ExpnId::root()); + return ExpnId::root(); } if let Some(expn_id) = ExpnId::from_hash(hash) { - return Ok(expn_id); + return expn_id; } let krate = decoder.tcx.stable_crate_id_to_crate_num(hash.stable_crate_id()); @@ -660,7 +649,7 @@ impl<'a, 'tcx> Decodable<CacheDecoder<'a, 'tcx>> for ExpnId { .unwrap_or_else(|| panic!("Bad hash {:?} (map {:?})", hash, decoder.expn_data)); let data: ExpnData = decoder - .with_position(pos.to_usize(), |decoder| decode_tagged(decoder, TAG_EXPN_DATA))?; + .with_position(pos.to_usize(), |decoder| decode_tagged(decoder, TAG_EXPN_DATA)); let expn_id = rustc_span::hygiene::register_local_expn_id(data, hash); #[cfg(debug_assertions)] @@ -687,21 +676,21 @@ impl<'a, 'tcx> Decodable<CacheDecoder<'a, 'tcx>> for ExpnId { }; debug_assert_eq!(expn_id.krate, krate); - Ok(expn_id) + expn_id } } impl<'a, 'tcx> Decodable<CacheDecoder<'a, 'tcx>> for Span { - fn decode(decoder: &mut CacheDecoder<'a, 'tcx>) -> Result<Self, String> { - let ctxt = SyntaxContext::decode(decoder)?; - let parent = Option::<LocalDefId>::decode(decoder)?; - let tag: u8 = Decodable::decode(decoder)?; + fn decode(decoder: &mut CacheDecoder<'a, 'tcx>) -> Self { + let ctxt = SyntaxContext::decode(decoder); + let parent = Option::<LocalDefId>::decode(decoder); + let tag: u8 = Decodable::decode(decoder); if tag == TAG_PARTIAL_SPAN { - return Ok(Span::new(BytePos(0), BytePos(0), ctxt, parent)); + return Span::new(BytePos(0), BytePos(0), ctxt, parent); } else if tag == TAG_RELATIVE_SPAN { - let dlo = u32::decode(decoder)?; - let dto = u32::decode(decoder)?; + let dlo = u32::decode(decoder); + let dto = u32::decode(decoder); let enclosing = decoder.tcx.definitions_untracked().def_span(parent.unwrap()).data_untracked(); @@ -712,29 +701,29 @@ impl<'a, 'tcx> Decodable<CacheDecoder<'a, 'tcx>> for Span { parent, ); - return Ok(span); + return span; } else { debug_assert_eq!(tag, TAG_FULL_SPAN); } - let file_lo_index = SourceFileIndex::decode(decoder)?; - let line_lo = usize::decode(decoder)?; - let col_lo = BytePos::decode(decoder)?; - let len = BytePos::decode(decoder)?; + let file_lo_index = SourceFileIndex::decode(decoder); + let line_lo = usize::decode(decoder); + let col_lo = BytePos::decode(decoder); + let len = BytePos::decode(decoder); let file_lo = decoder.file_index_to_file(file_lo_index); let lo = file_lo.lines[line_lo - 1] + col_lo; let hi = lo + len; - Ok(Span::new(lo, hi, ctxt, parent)) + Span::new(lo, hi, ctxt, parent) } } impl<'a, 'tcx> Decodable<CacheDecoder<'a, 'tcx>> for CrateNum { - fn decode(d: &mut CacheDecoder<'a, 'tcx>) -> Result<Self, String> { - let stable_id = StableCrateId::decode(d)?; + fn decode(d: &mut CacheDecoder<'a, 'tcx>) -> Self { + let stable_id = StableCrateId::decode(d); let cnum = d.tcx.stable_crate_id_to_crate_num(stable_id); - Ok(cnum) + cnum } } @@ -743,8 +732,8 @@ impl<'a, 'tcx> Decodable<CacheDecoder<'a, 'tcx>> for CrateNum { // because we would not know how to transform the `DefIndex` to the current // context. impl<'a, 'tcx> Decodable<CacheDecoder<'a, 'tcx>> for DefIndex { - fn decode(d: &mut CacheDecoder<'a, 'tcx>) -> Result<DefIndex, String> { - Err(d.error("trying to decode `DefIndex` outside the context of a `DefId`")) + fn decode(_d: &mut CacheDecoder<'a, 'tcx>) -> DefIndex { + panic!("trying to decode `DefIndex` outside the context of a `DefId`") } } @@ -752,23 +741,23 @@ impl<'a, 'tcx> Decodable<CacheDecoder<'a, 'tcx>> for DefIndex { // compilation sessions. We use the `DefPathHash`, which is stable across // sessions, to map the old `DefId` to the new one. impl<'a, 'tcx> Decodable<CacheDecoder<'a, 'tcx>> for DefId { - fn decode(d: &mut CacheDecoder<'a, 'tcx>) -> Result<Self, String> { + fn decode(d: &mut CacheDecoder<'a, 'tcx>) -> Self { // Load the `DefPathHash` which is was we encoded the `DefId` as. - let def_path_hash = DefPathHash::decode(d)?; + let def_path_hash = DefPathHash::decode(d); // Using the `DefPathHash`, we can lookup the new `DefId`. // Subtle: We only encode a `DefId` as part of a query result. // If we get to this point, then all of the query inputs were green, // which means that the definition with this hash is guaranteed to // still exist in the current compilation session. - Ok(d.tcx().def_path_hash_to_def_id(def_path_hash, &mut || { + d.tcx().def_path_hash_to_def_id(def_path_hash, &mut || { panic!("Failed to convert DefPathHash {:?}", def_path_hash) - })) + }) } } impl<'a, 'tcx> Decodable<CacheDecoder<'a, 'tcx>> for &'tcx FxHashSet<LocalDefId> { - fn decode(d: &mut CacheDecoder<'a, 'tcx>) -> Result<Self, String> { + fn decode(d: &mut CacheDecoder<'a, 'tcx>) -> Self { RefDecodable::decode(d) } } @@ -776,31 +765,31 @@ impl<'a, 'tcx> Decodable<CacheDecoder<'a, 'tcx>> for &'tcx FxHashSet<LocalDefId> impl<'a, 'tcx> Decodable<CacheDecoder<'a, 'tcx>> for &'tcx IndexVec<mir::Promoted, mir::Body<'tcx>> { - fn decode(d: &mut CacheDecoder<'a, 'tcx>) -> Result<Self, String> { + fn decode(d: &mut CacheDecoder<'a, 'tcx>) -> Self { RefDecodable::decode(d) } } impl<'a, 'tcx> Decodable<CacheDecoder<'a, 'tcx>> for &'tcx [thir::abstract_const::Node<'tcx>] { - fn decode(d: &mut CacheDecoder<'a, 'tcx>) -> Result<Self, String> { + fn decode(d: &mut CacheDecoder<'a, 'tcx>) -> Self { RefDecodable::decode(d) } } impl<'a, 'tcx> Decodable<CacheDecoder<'a, 'tcx>> for &'tcx [(ty::Predicate<'tcx>, Span)] { - fn decode(d: &mut CacheDecoder<'a, 'tcx>) -> Result<Self, String> { + fn decode(d: &mut CacheDecoder<'a, 'tcx>) -> Self { RefDecodable::decode(d) } } impl<'a, 'tcx> Decodable<CacheDecoder<'a, 'tcx>> for &'tcx [rustc_ast::InlineAsmTemplatePiece] { - fn decode(d: &mut CacheDecoder<'a, 'tcx>) -> Result<Self, String> { + fn decode(d: &mut CacheDecoder<'a, 'tcx>) -> Self { RefDecodable::decode(d) } } impl<'a, 'tcx> Decodable<CacheDecoder<'a, 'tcx>> for &'tcx [Span] { - fn decode(d: &mut CacheDecoder<'a, 'tcx>) -> Result<Self, String> { + fn decode(d: &mut CacheDecoder<'a, 'tcx>) -> Self { RefDecodable::decode(d) } } diff --git a/compiler/rustc_query_system/src/dep_graph/serialized.rs b/compiler/rustc_query_system/src/dep_graph/serialized.rs index 47197a1e492..2fc626a75b3 100644 --- a/compiler/rustc_query_system/src/dep_graph/serialized.rs +++ b/compiler/rustc_query_system/src/dep_graph/serialized.rs @@ -100,7 +100,7 @@ impl<'a, K: DepKind + Decodable<opaque::Decoder<'a>>> Decodable<opaque::Decoder< for SerializedDepGraph<K> { #[instrument(level = "debug", skip(d))] - fn decode(d: &mut opaque::Decoder<'a>) -> Result<SerializedDepGraph<K>, String> { + fn decode(d: &mut opaque::Decoder<'a>) -> SerializedDepGraph<K> { let start_position = d.position(); // The last 16 bytes are the node count and edge count. @@ -108,8 +108,8 @@ impl<'a, K: DepKind + Decodable<opaque::Decoder<'a>>> Decodable<opaque::Decoder< d.set_position(d.data.len() - 2 * IntEncodedWithFixedSize::ENCODED_SIZE); debug!("position: {:?}", d.position()); - let node_count = IntEncodedWithFixedSize::decode(d)?.0 as usize; - let edge_count = IntEncodedWithFixedSize::decode(d)?.0 as usize; + let node_count = IntEncodedWithFixedSize::decode(d).0 as usize; + let edge_count = IntEncodedWithFixedSize::decode(d).0 as usize; debug!(?node_count, ?edge_count); debug!("position: {:?}", d.position()); @@ -123,12 +123,12 @@ impl<'a, K: DepKind + Decodable<opaque::Decoder<'a>>> Decodable<opaque::Decoder< for _index in 0..node_count { d.read_struct(|d| { - let dep_node: DepNode<K> = d.read_struct_field("node", Decodable::decode)?; + let dep_node: DepNode<K> = d.read_struct_field("node", Decodable::decode); let _i: SerializedDepNodeIndex = nodes.push(dep_node); debug_assert_eq!(_i.index(), _index); let fingerprint: Fingerprint = - d.read_struct_field("fingerprint", Decodable::decode)?; + d.read_struct_field("fingerprint", Decodable::decode); let _i: SerializedDepNodeIndex = fingerprints.push(fingerprint); debug_assert_eq!(_i.index(), _index); @@ -136,22 +136,22 @@ impl<'a, K: DepKind + Decodable<opaque::Decoder<'a>>> Decodable<opaque::Decoder< d.read_seq(|d, len| { let start = edge_list_data.len().try_into().unwrap(); for _ in 0..len { - let edge = d.read_seq_elt(Decodable::decode)?; + let edge = d.read_seq_elt(Decodable::decode); edge_list_data.push(edge); } let end = edge_list_data.len().try_into().unwrap(); let _i: SerializedDepNodeIndex = edge_list_indices.push((start, end)); debug_assert_eq!(_i.index(), _index); - Ok(()) + () }) }) - })?; + }); } let index: FxHashMap<_, _> = nodes.iter_enumerated().map(|(idx, &dep_node)| (dep_node, idx)).collect(); - Ok(SerializedDepGraph { nodes, fingerprints, edge_list_indices, edge_list_data, index }) + SerializedDepGraph { nodes, fingerprints, edge_list_indices, edge_list_data, index } } } diff --git a/compiler/rustc_serialize/src/collection_impls.rs b/compiler/rustc_serialize/src/collection_impls.rs index 80a7f650188..02b28f7c626 100644 --- a/compiler/rustc_serialize/src/collection_impls.rs +++ b/compiler/rustc_serialize/src/collection_impls.rs @@ -17,15 +17,8 @@ impl<S: Encoder, A: Array<Item: Encodable<S>>> Encodable<S> for SmallVec<A> { } impl<D: Decoder, A: Array<Item: Decodable<D>>> Decodable<D> for SmallVec<A> { - fn decode(d: &mut D) -> Result<SmallVec<A>, D::Error> { - d.read_seq(|d, len| { - let mut vec = SmallVec::with_capacity(len); - // FIXME(#48994) - could just be collected into a Result<SmallVec, D::Error> - for _ in 0..len { - vec.push(d.read_seq_elt(|d| Decodable::decode(d))?); - } - Ok(vec) - }) + fn decode(d: &mut D) -> SmallVec<A> { + d.read_seq(|d, len| (0..len).map(|_| d.read_seq_elt(|d| Decodable::decode(d))).collect()) } } @@ -41,14 +34,8 @@ impl<S: Encoder, T: Encodable<S>> Encodable<S> for LinkedList<T> { } impl<D: Decoder, T: Decodable<D>> Decodable<D> for LinkedList<T> { - fn decode(d: &mut D) -> Result<LinkedList<T>, D::Error> { - d.read_seq(|d, len| { - let mut list = LinkedList::new(); - for _ in 0..len { - list.push_back(d.read_seq_elt(|d| Decodable::decode(d))?); - } - Ok(list) - }) + fn decode(d: &mut D) -> LinkedList<T> { + d.read_seq(|d, len| (0..len).map(|_| d.read_seq_elt(|d| Decodable::decode(d))).collect()) } } @@ -64,14 +51,8 @@ impl<S: Encoder, T: Encodable<S>> Encodable<S> for VecDeque<T> { } impl<D: Decoder, T: Decodable<D>> Decodable<D> for VecDeque<T> { - fn decode(d: &mut D) -> Result<VecDeque<T>, D::Error> { - d.read_seq(|d, len| { - let mut deque: VecDeque<T> = VecDeque::with_capacity(len); - for _ in 0..len { - deque.push_back(d.read_seq_elt(|d| Decodable::decode(d))?); - } - Ok(deque) - }) + fn decode(d: &mut D) -> VecDeque<T> { + d.read_seq(|d, len| (0..len).map(|_| d.read_seq_elt(|d| Decodable::decode(d))).collect()) } } @@ -96,15 +77,15 @@ where K: Decodable<D> + PartialEq + Ord, V: Decodable<D>, { - fn decode(d: &mut D) -> Result<BTreeMap<K, V>, D::Error> { + fn decode(d: &mut D) -> BTreeMap<K, V> { d.read_map(|d, len| { let mut map = BTreeMap::new(); for _ in 0..len { - let key = d.read_map_elt_key(|d| Decodable::decode(d))?; - let val = d.read_map_elt_val(|d| Decodable::decode(d))?; + let key = d.read_map_elt_key(|d| Decodable::decode(d)); + let val = d.read_map_elt_val(|d| Decodable::decode(d)); map.insert(key, val); } - Ok(map) + map }) } } @@ -127,13 +108,13 @@ impl<D: Decoder, T> Decodable<D> for BTreeSet<T> where T: Decodable<D> + PartialEq + Ord, { - fn decode(d: &mut D) -> Result<BTreeSet<T>, D::Error> { + fn decode(d: &mut D) -> BTreeSet<T> { d.read_seq(|d, len| { let mut set = BTreeSet::new(); for _ in 0..len { - set.insert(d.read_seq_elt(|d| Decodable::decode(d))?); + set.insert(d.read_seq_elt(|d| Decodable::decode(d))); } - Ok(set) + set }) } } @@ -161,16 +142,16 @@ where V: Decodable<D>, S: BuildHasher + Default, { - fn decode(d: &mut D) -> Result<HashMap<K, V, S>, D::Error> { + fn decode(d: &mut D) -> HashMap<K, V, S> { d.read_map(|d, len| { let state = Default::default(); let mut map = HashMap::with_capacity_and_hasher(len, state); for _ in 0..len { - let key = d.read_map_elt_key(|d| Decodable::decode(d))?; - let val = d.read_map_elt_val(|d| Decodable::decode(d))?; + let key = d.read_map_elt_key(|d| Decodable::decode(d)); + let val = d.read_map_elt_val(|d| Decodable::decode(d)); map.insert(key, val); } - Ok(map) + map }) } } @@ -205,14 +186,14 @@ where T: Decodable<D> + Hash + Eq, S: BuildHasher + Default, { - fn decode(d: &mut D) -> Result<HashSet<T, S>, D::Error> { + fn decode(d: &mut D) -> HashSet<T, S> { d.read_seq(|d, len| { let state = Default::default(); let mut set = HashSet::with_capacity_and_hasher(len, state); for _ in 0..len { - set.insert(d.read_seq_elt(|d| Decodable::decode(d))?); + set.insert(d.read_seq_elt(|d| Decodable::decode(d))); } - Ok(set) + set }) } } @@ -240,16 +221,16 @@ where V: Decodable<D>, S: BuildHasher + Default, { - fn decode(d: &mut D) -> Result<indexmap::IndexMap<K, V, S>, D::Error> { + fn decode(d: &mut D) -> indexmap::IndexMap<K, V, S> { d.read_map(|d, len| { let state = Default::default(); let mut map = indexmap::IndexMap::with_capacity_and_hasher(len, state); for _ in 0..len { - let key = d.read_map_elt_key(|d| Decodable::decode(d))?; - let val = d.read_map_elt_val(|d| Decodable::decode(d))?; + let key = d.read_map_elt_key(|d| Decodable::decode(d)); + let val = d.read_map_elt_val(|d| Decodable::decode(d)); map.insert(key, val); } - Ok(map) + map }) } } @@ -274,14 +255,14 @@ where T: Decodable<D> + Hash + Eq, S: BuildHasher + Default, { - fn decode(d: &mut D) -> Result<indexmap::IndexSet<T, S>, D::Error> { + fn decode(d: &mut D) -> indexmap::IndexSet<T, S> { d.read_seq(|d, len| { let state = Default::default(); let mut set = indexmap::IndexSet::with_capacity_and_hasher(len, state); for _ in 0..len { - set.insert(d.read_seq_elt(|d| Decodable::decode(d))?); + set.insert(d.read_seq_elt(|d| Decodable::decode(d))); } - Ok(set) + set }) } } @@ -294,9 +275,9 @@ impl<E: Encoder, T: Encodable<E>> Encodable<E> for Rc<[T]> { } impl<D: Decoder, T: Decodable<D>> Decodable<D> for Rc<[T]> { - fn decode(d: &mut D) -> Result<Rc<[T]>, D::Error> { - let vec: Vec<T> = Decodable::decode(d)?; - Ok(vec.into()) + fn decode(d: &mut D) -> Rc<[T]> { + let vec: Vec<T> = Decodable::decode(d); + vec.into() } } @@ -308,8 +289,8 @@ impl<E: Encoder, T: Encodable<E>> Encodable<E> for Arc<[T]> { } impl<D: Decoder, T: Decodable<D>> Decodable<D> for Arc<[T]> { - fn decode(d: &mut D) -> Result<Arc<[T]>, D::Error> { - let vec: Vec<T> = Decodable::decode(d)?; - Ok(vec.into()) + fn decode(d: &mut D) -> Arc<[T]> { + let vec: Vec<T> = Decodable::decode(d); + vec.into() } } diff --git a/compiler/rustc_serialize/src/json.rs b/compiler/rustc_serialize/src/json.rs index d3d72ba72a7..c005db12099 100644 --- a/compiler/rustc_serialize/src/json.rs +++ b/compiler/rustc_serialize/src/json.rs @@ -89,7 +89,7 @@ //! let encoded = json::encode(&object).unwrap(); //! //! // Deserialize using `json::decode` -//! let decoded: TestStruct = json::decode(&encoded[..]).unwrap(); +//! let decoded: TestStruct = json::decode(&encoded[..]); //! ``` //! //! ## Using the `ToJson` trait @@ -173,7 +173,7 @@ //! let json_str: String = json_obj.to_string(); //! //! // Deserialize like before -//! let decoded: TestStruct = json::decode(&json_str).unwrap(); +//! let decoded: TestStruct = json::decode(&json_str); //! ``` use self::DecoderError::*; @@ -265,6 +265,12 @@ pub enum DecoderError { ApplicationError(string::String), } +macro_rules! bad { + ($e:expr) => {{ + panic!("json decode error: {:?}", $e); + }}; +} + #[derive(Copy, Clone, Debug)] pub enum EncoderError { FmtError(fmt::Error), @@ -295,10 +301,10 @@ pub fn error_str(error: ErrorCode) -> &'static str { } /// Shortcut function to decode a JSON `&str` into an object -pub fn decode<T: crate::Decodable<Decoder>>(s: &str) -> DecodeResult<T> { +pub fn decode<T: crate::Decodable<Decoder>>(s: &str) -> T { let json = match from_str(s) { Ok(x) => x, - Err(e) => return Err(ParseError(e)), + Err(e) => bad!(ParseError(e)), }; let mut decoder = Decoder::new(json); @@ -334,15 +340,6 @@ impl fmt::Display for ParserError { } } -impl fmt::Display for DecoderError { - fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { - // FIXME this should be a nicer error - fmt::Debug::fmt(self, f) - } -} - -impl std::error::Error for DecoderError {} - impl fmt::Display for EncoderError { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { // FIXME this should be a nicer error @@ -2206,41 +2203,39 @@ impl Decoder { macro_rules! expect { ($e:expr, Null) => {{ match $e { - Json::Null => Ok(()), - other => Err(ExpectedError("Null".to_owned(), other.to_string())), + Json::Null => (), + other => bad!(ExpectedError("Null".to_owned(), other.to_string())), } }}; ($e:expr, $t:ident) => {{ match $e { - Json::$t(v) => Ok(v), - other => Err(ExpectedError(stringify!($t).to_owned(), other.to_string())), + Json::$t(v) => v, + other => bad!(ExpectedError(stringify!($t).to_owned(), other.to_string())), } }}; } macro_rules! read_primitive { ($name:ident, $ty:ty) => { - fn $name(&mut self) -> DecodeResult<$ty> { + fn $name(&mut self) -> $ty { match self.pop() { - Json::I64(f) => Ok(f as $ty), - Json::U64(f) => Ok(f as $ty), - Json::F64(f) => Err(ExpectedError("Integer".to_owned(), f.to_string())), + Json::I64(f) => f as $ty, + Json::U64(f) => f as $ty, + Json::F64(f) => bad!(ExpectedError("Integer".to_owned(), f.to_string())), // re: #12967.. a type w/ numeric keys (ie HashMap<usize, V> etc) // is going to have a string here, as per JSON spec. Json::String(s) => match s.parse().ok() { - Some(f) => Ok(f), - None => Err(ExpectedError("Number".to_owned(), s)), + Some(f) => f, + None => bad!(ExpectedError("Number".to_owned(), s)), }, - value => Err(ExpectedError("Number".to_owned(), value.to_string())), + value => bad!(ExpectedError("Number".to_owned(), value.to_string())), } } }; } impl crate::Decoder for Decoder { - type Error = DecoderError; - - fn read_unit(&mut self) -> DecodeResult<()> { + fn read_unit(&mut self) -> () { expect!(self.pop(), Null) } @@ -2257,156 +2252,151 @@ impl crate::Decoder for Decoder { read_primitive! { read_i64, i64 } read_primitive! { read_i128, i128 } - fn read_f32(&mut self) -> DecodeResult<f32> { - self.read_f64().map(|x| x as f32) + fn read_f32(&mut self) -> f32 { + self.read_f64() as f32 } - fn read_f64(&mut self) -> DecodeResult<f64> { + fn read_f64(&mut self) -> f64 { match self.pop() { - Json::I64(f) => Ok(f as f64), - Json::U64(f) => Ok(f as f64), - Json::F64(f) => Ok(f), + Json::I64(f) => f as f64, + Json::U64(f) => f as f64, + Json::F64(f) => f, Json::String(s) => { // re: #12967.. a type w/ numeric keys (ie HashMap<usize, V> etc) // is going to have a string here, as per JSON spec. match s.parse().ok() { - Some(f) => Ok(f), - None => Err(ExpectedError("Number".to_owned(), s)), + Some(f) => f, + None => bad!(ExpectedError("Number".to_owned(), s)), } } - Json::Null => Ok(f64::NAN), - value => Err(ExpectedError("Number".to_owned(), value.to_string())), + Json::Null => f64::NAN, + value => bad!(ExpectedError("Number".to_owned(), value.to_string())), } } - fn read_bool(&mut self) -> DecodeResult<bool> { + fn read_bool(&mut self) -> bool { expect!(self.pop(), Boolean) } - fn read_char(&mut self) -> DecodeResult<char> { - let s = self.read_str()?; - { - let mut it = s.chars(); - if let (Some(c), None) = (it.next(), it.next()) { - // exactly one character - return Ok(c); - } + fn read_char(&mut self) -> char { + let s = self.read_str(); + let mut it = s.chars(); + if let (Some(c), None) = (it.next(), it.next()) { + // exactly one character + return c; } - Err(ExpectedError("single character string".to_owned(), s.to_string())) + bad!(ExpectedError("single character string".to_owned(), s.to_string())); } - fn read_str(&mut self) -> DecodeResult<Cow<'_, str>> { - expect!(self.pop(), String).map(Cow::Owned) + fn read_str(&mut self) -> Cow<'_, str> { + Cow::Owned(expect!(self.pop(), String)) } - fn read_raw_bytes_into(&mut self, s: &mut [u8]) -> Result<(), Self::Error> { + fn read_raw_bytes_into(&mut self, s: &mut [u8]) { for c in s.iter_mut() { - *c = self.read_u8()?; + *c = self.read_u8(); } - Ok(()) + () } - fn read_enum<T, F>(&mut self, f: F) -> DecodeResult<T> + fn read_enum<T, F>(&mut self, f: F) -> T where - F: FnOnce(&mut Decoder) -> DecodeResult<T>, + F: FnOnce(&mut Decoder) -> T, { f(self) } - fn read_enum_variant<T, F>(&mut self, names: &[&str], mut f: F) -> DecodeResult<T> + fn read_enum_variant<T, F>(&mut self, names: &[&str], mut f: F) -> T where - F: FnMut(&mut Decoder, usize) -> DecodeResult<T>, + F: FnMut(&mut Decoder, usize) -> T, { let name = match self.pop() { Json::String(s) => s, Json::Object(mut o) => { let n = match o.remove("variant") { Some(Json::String(s)) => s, - Some(val) => return Err(ExpectedError("String".to_owned(), val.to_string())), - None => return Err(MissingFieldError("variant".to_owned())), + Some(val) => bad!(ExpectedError("String".to_owned(), val.to_string())), + None => bad!(MissingFieldError("variant".to_owned())), }; match o.remove("fields") { Some(Json::Array(l)) => { self.stack.extend(l.into_iter().rev()); } - Some(val) => return Err(ExpectedError("Array".to_owned(), val.to_string())), - None => return Err(MissingFieldError("fields".to_owned())), + Some(val) => bad!(ExpectedError("Array".to_owned(), val.to_string())), + None => bad!(MissingFieldError("fields".to_owned())), } n } - json => return Err(ExpectedError("String or Object".to_owned(), json.to_string())), + json => bad!(ExpectedError("String or Object".to_owned(), json.to_string())), }; let idx = match names.iter().position(|n| *n == &name[..]) { Some(idx) => idx, - None => return Err(UnknownVariantError(name)), + None => bad!(UnknownVariantError(name)), }; f(self, idx) } - fn read_enum_variant_arg<T, F>(&mut self, f: F) -> DecodeResult<T> + fn read_enum_variant_arg<T, F>(&mut self, f: F) -> T where - F: FnOnce(&mut Decoder) -> DecodeResult<T>, + F: FnOnce(&mut Decoder) -> T, { f(self) } - fn read_struct<T, F>(&mut self, f: F) -> DecodeResult<T> + fn read_struct<T, F>(&mut self, f: F) -> T where - F: FnOnce(&mut Decoder) -> DecodeResult<T>, + F: FnOnce(&mut Decoder) -> T, { - let value = f(self)?; + let value = f(self); self.pop(); - Ok(value) + value } - fn read_struct_field<T, F>(&mut self, name: &str, f: F) -> DecodeResult<T> + fn read_struct_field<T, F>(&mut self, name: &str, f: F) -> T where - F: FnOnce(&mut Decoder) -> DecodeResult<T>, + F: FnOnce(&mut Decoder) -> T, { - let mut obj = expect!(self.pop(), Object)?; + let mut obj = expect!(self.pop(), Object); let value = match obj.remove(name) { None => { // Add a Null and try to parse it as an Option<_> // to get None as a default value. self.stack.push(Json::Null); - match f(self) { - Ok(x) => x, - Err(_) => return Err(MissingFieldError(name.to_string())), - } + f(self) } Some(json) => { self.stack.push(json); - f(self)? + f(self) } }; self.stack.push(Json::Object(obj)); - Ok(value) + value } - fn read_tuple<T, F>(&mut self, tuple_len: usize, f: F) -> DecodeResult<T> + fn read_tuple<T, F>(&mut self, tuple_len: usize, f: F) -> T where - F: FnOnce(&mut Decoder) -> DecodeResult<T>, + F: FnOnce(&mut Decoder) -> T, { self.read_seq(move |d, len| { if len == tuple_len { f(d) } else { - Err(ExpectedError(format!("Tuple{}", tuple_len), format!("Tuple{}", len))) + bad!(ExpectedError(format!("Tuple{}", tuple_len), format!("Tuple{}", len))); } }) } - fn read_tuple_arg<T, F>(&mut self, f: F) -> DecodeResult<T> + fn read_tuple_arg<T, F>(&mut self, f: F) -> T where - F: FnOnce(&mut Decoder) -> DecodeResult<T>, + F: FnOnce(&mut Decoder) -> T, { self.read_seq_elt(f) } - fn read_option<T, F>(&mut self, mut f: F) -> DecodeResult<T> + fn read_option<T, F>(&mut self, mut f: F) -> T where - F: FnMut(&mut Decoder, bool) -> DecodeResult<T>, + F: FnMut(&mut Decoder, bool) -> T, { match self.pop() { Json::Null => f(self, false), @@ -2417,28 +2407,28 @@ impl crate::Decoder for Decoder { } } - fn read_seq<T, F>(&mut self, f: F) -> DecodeResult<T> + fn read_seq<T, F>(&mut self, f: F) -> T where - F: FnOnce(&mut Decoder, usize) -> DecodeResult<T>, + F: FnOnce(&mut Decoder, usize) -> T, { - let array = expect!(self.pop(), Array)?; + let array = expect!(self.pop(), Array); let len = array.len(); self.stack.extend(array.into_iter().rev()); f(self, len) } - fn read_seq_elt<T, F>(&mut self, f: F) -> DecodeResult<T> + fn read_seq_elt<T, F>(&mut self, f: F) -> T where - F: FnOnce(&mut Decoder) -> DecodeResult<T>, + F: FnOnce(&mut Decoder) -> T, { f(self) } - fn read_map<T, F>(&mut self, f: F) -> DecodeResult<T> + fn read_map<T, F>(&mut self, f: F) -> T where - F: FnOnce(&mut Decoder, usize) -> DecodeResult<T>, + F: FnOnce(&mut Decoder, usize) -> T, { - let obj = expect!(self.pop(), Object)?; + let obj = expect!(self.pop(), Object); let len = obj.len(); for (key, value) in obj { self.stack.push(value); @@ -2447,23 +2437,19 @@ impl crate::Decoder for Decoder { f(self, len) } - fn read_map_elt_key<T, F>(&mut self, f: F) -> DecodeResult<T> + fn read_map_elt_key<T, F>(&mut self, f: F) -> T where - F: FnOnce(&mut Decoder) -> DecodeResult<T>, + F: FnOnce(&mut Decoder) -> T, { f(self) } - fn read_map_elt_val<T, F>(&mut self, f: F) -> DecodeResult<T> + fn read_map_elt_val<T, F>(&mut self, f: F) -> T where - F: FnOnce(&mut Decoder) -> DecodeResult<T>, + F: FnOnce(&mut Decoder) -> T, { f(self) } - - fn error(&mut self, err: &str) -> DecoderError { - ApplicationError(err.to_string()) - } } /// A trait for converting values to JSON diff --git a/compiler/rustc_serialize/src/opaque.rs b/compiler/rustc_serialize/src/opaque.rs index 7e515abbe7b..89ac7834a39 100644 --- a/compiler/rustc_serialize/src/opaque.rs +++ b/compiler/rustc_serialize/src/opaque.rs @@ -560,134 +560,127 @@ impl<'a> Decoder<'a> { } macro_rules! read_leb128 { - ($dec:expr, $fun:ident) => {{ Ok(leb128::$fun($dec.data, &mut $dec.position)) }}; + ($dec:expr, $fun:ident) => {{ leb128::$fun($dec.data, &mut $dec.position) }}; } impl<'a> serialize::Decoder for Decoder<'a> { - type Error = String; - #[inline] - fn read_unit(&mut self) -> Result<(), Self::Error> { - Ok(()) + fn read_unit(&mut self) -> () { + () } #[inline] - fn read_u128(&mut self) -> Result<u128, Self::Error> { + fn read_u128(&mut self) -> u128 { read_leb128!(self, read_u128_leb128) } #[inline] - fn read_u64(&mut self) -> Result<u64, Self::Error> { + fn read_u64(&mut self) -> u64 { read_leb128!(self, read_u64_leb128) } #[inline] - fn read_u32(&mut self) -> Result<u32, Self::Error> { + fn read_u32(&mut self) -> u32 { read_leb128!(self, read_u32_leb128) } #[inline] - fn read_u16(&mut self) -> Result<u16, Self::Error> { + fn read_u16(&mut self) -> u16 { let bytes = [self.data[self.position], self.data[self.position + 1]]; let value = u16::from_le_bytes(bytes); self.position += 2; - Ok(value) + value } #[inline] - fn read_u8(&mut self) -> Result<u8, Self::Error> { + fn read_u8(&mut self) -> u8 { let value = self.data[self.position]; self.position += 1; - Ok(value) + value } #[inline] - fn read_usize(&mut self) -> Result<usize, Self::Error> { + fn read_usize(&mut self) -> usize { read_leb128!(self, read_usize_leb128) } #[inline] - fn read_i128(&mut self) -> Result<i128, Self::Error> { + fn read_i128(&mut self) -> i128 { read_leb128!(self, read_i128_leb128) } #[inline] - fn read_i64(&mut self) -> Result<i64, Self::Error> { + fn read_i64(&mut self) -> i64 { read_leb128!(self, read_i64_leb128) } #[inline] - fn read_i32(&mut self) -> Result<i32, Self::Error> { + fn read_i32(&mut self) -> i32 { read_leb128!(self, read_i32_leb128) } #[inline] - fn read_i16(&mut self) -> Result<i16, Self::Error> { + fn read_i16(&mut self) -> i16 { let bytes = [self.data[self.position], self.data[self.position + 1]]; let value = i16::from_le_bytes(bytes); self.position += 2; - Ok(value) + value } #[inline] - fn read_i8(&mut self) -> Result<i8, Self::Error> { + fn read_i8(&mut self) -> i8 { let as_u8 = self.data[self.position]; self.position += 1; - unsafe { Ok(::std::mem::transmute(as_u8)) } + unsafe { ::std::mem::transmute(as_u8) } } #[inline] - fn read_isize(&mut self) -> Result<isize, Self::Error> { + fn read_isize(&mut self) -> isize { read_leb128!(self, read_isize_leb128) } #[inline] - fn read_bool(&mut self) -> Result<bool, Self::Error> { - let value = self.read_u8()?; - Ok(value != 0) + fn read_bool(&mut self) -> bool { + let value = self.read_u8(); + value != 0 } #[inline] - fn read_f64(&mut self) -> Result<f64, Self::Error> { - let bits = self.read_u64()?; - Ok(f64::from_bits(bits)) + fn read_f64(&mut self) -> f64 { + let bits = self.read_u64(); + f64::from_bits(bits) } #[inline] - fn read_f32(&mut self) -> Result<f32, Self::Error> { - let bits = self.read_u32()?; - Ok(f32::from_bits(bits)) + fn read_f32(&mut self) -> f32 { + let bits = self.read_u32(); + f32::from_bits(bits) } #[inline] - fn read_char(&mut self) -> Result<char, Self::Error> { - let bits = self.read_u32()?; - Ok(std::char::from_u32(bits).unwrap()) + fn read_char(&mut self) -> char { + let bits = self.read_u32(); + std::char::from_u32(bits).unwrap() } #[inline] - fn read_str(&mut self) -> Result<Cow<'_, str>, Self::Error> { - let len = self.read_usize()?; + fn read_str(&mut self) -> Cow<'_, str> { + let len = self.read_usize(); let sentinel = self.data[self.position + len]; assert!(sentinel == STR_SENTINEL); let s = unsafe { std::str::from_utf8_unchecked(&self.data[self.position..self.position + len]) }; self.position += len + 1; - Ok(Cow::Borrowed(s)) - } - - #[inline] - fn error(&mut self, err: &str) -> Self::Error { - err.to_string() + Cow::Borrowed(s) } #[inline] - fn read_raw_bytes_into(&mut self, s: &mut [u8]) -> Result<(), String> { + fn read_raw_bytes_into(&mut self, s: &mut [u8]) -> () { let start = self.position; self.position += s.len(); s.copy_from_slice(&self.data[start..self.position]); - Ok(()) + () } } @@ -715,9 +708,9 @@ impl serialize::Encodable<FileEncoder> for [u8] { // Specialize decoding `Vec<u8>`. This specialization also applies to decoding `Box<[u8]>`s, etc., // since the default implementations call `decode` to produce a `Vec<u8>` internally. impl<'a> serialize::Decodable<Decoder<'a>> for Vec<u8> { - fn decode(d: &mut Decoder<'a>) -> Result<Self, String> { - let len = serialize::Decoder::read_usize(d)?; - Ok(d.read_raw_bytes(len).to_owned()) + fn decode(d: &mut Decoder<'a>) -> Self { + let len = serialize::Decoder::read_usize(d); + d.read_raw_bytes(len).to_owned() } } @@ -752,13 +745,13 @@ impl serialize::Encodable<FileEncoder> for IntEncodedWithFixedSize { impl<'a> serialize::Decodable<Decoder<'a>> for IntEncodedWithFixedSize { #[inline] - fn decode(decoder: &mut Decoder<'a>) -> Result<IntEncodedWithFixedSize, String> { + fn decode(decoder: &mut Decoder<'a>) -> IntEncodedWithFixedSize { let _start_pos = decoder.position(); let bytes = decoder.read_raw_bytes(IntEncodedWithFixedSize::ENCODED_SIZE); let _end_pos = decoder.position(); debug_assert_eq!((_end_pos - _start_pos), IntEncodedWithFixedSize::ENCODED_SIZE); let value = u64::from_le_bytes(bytes.try_into().unwrap()); - Ok(IntEncodedWithFixedSize(value)) + IntEncodedWithFixedSize(value) } } diff --git a/compiler/rustc_serialize/src/serialize.rs b/compiler/rustc_serialize/src/serialize.rs index e5104b14724..a6172403fd6 100644 --- a/compiler/rustc_serialize/src/serialize.rs +++ b/compiler/rustc_serialize/src/serialize.rs @@ -173,144 +173,145 @@ pub trait Encoder { } } +// Note: all the methods in this trait are infallible, which may be surprising. +// They used to be fallible (i.e. return a `Result`) but many of the impls just +// panicked when something went wrong, and for the cases that didn't the +// top-level invocation would also just panic on failure. Switching to +// infallibility made things faster and lots of code a little simpler and more +// concise. pub trait Decoder { - type Error; - // Primitive types: - fn read_unit(&mut self) -> Result<(), Self::Error>; - fn read_usize(&mut self) -> Result<usize, Self::Error>; - fn read_u128(&mut self) -> Result<u128, Self::Error>; - fn read_u64(&mut self) -> Result<u64, Self::Error>; - fn read_u32(&mut self) -> Result<u32, Self::Error>; - fn read_u16(&mut self) -> Result<u16, Self::Error>; - fn read_u8(&mut self) -> Result<u8, Self::Error>; - fn read_isize(&mut self) -> Result<isize, Self::Error>; - fn read_i128(&mut self) -> Result<i128, Self::Error>; - fn read_i64(&mut self) -> Result<i64, Self::Error>; - fn read_i32(&mut self) -> Result<i32, Self::Error>; - fn read_i16(&mut self) -> Result<i16, Self::Error>; - fn read_i8(&mut self) -> Result<i8, Self::Error>; - fn read_bool(&mut self) -> Result<bool, Self::Error>; - fn read_f64(&mut self) -> Result<f64, Self::Error>; - fn read_f32(&mut self) -> Result<f32, Self::Error>; - fn read_char(&mut self) -> Result<char, Self::Error>; - fn read_str(&mut self) -> Result<Cow<'_, str>, Self::Error>; - fn read_raw_bytes_into(&mut self, s: &mut [u8]) -> Result<(), Self::Error>; + fn read_unit(&mut self) -> (); + fn read_usize(&mut self) -> usize; + fn read_u128(&mut self) -> u128; + fn read_u64(&mut self) -> u64; + fn read_u32(&mut self) -> u32; + fn read_u16(&mut self) -> u16; + fn read_u8(&mut self) -> u8; + fn read_isize(&mut self) -> isize; + fn read_i128(&mut self) -> i128; + fn read_i64(&mut self) -> i64; + fn read_i32(&mut self) -> i32; + fn read_i16(&mut self) -> i16; + fn read_i8(&mut self) -> i8; + fn read_bool(&mut self) -> bool; + fn read_f64(&mut self) -> f64; + fn read_f32(&mut self) -> f32; + fn read_char(&mut self) -> char; + fn read_str(&mut self) -> Cow<'_, str>; + fn read_raw_bytes_into(&mut self, s: &mut [u8]); // Compound types: #[inline] - fn read_enum<T, F>(&mut self, f: F) -> Result<T, Self::Error> + fn read_enum<T, F>(&mut self, f: F) -> T where - F: FnOnce(&mut Self) -> Result<T, Self::Error>, + F: FnOnce(&mut Self) -> T, { f(self) } #[inline] - fn read_enum_variant<T, F>(&mut self, _names: &[&str], mut f: F) -> Result<T, Self::Error> + fn read_enum_variant<T, F>(&mut self, _names: &[&str], mut f: F) -> T where - F: FnMut(&mut Self, usize) -> Result<T, Self::Error>, + F: FnMut(&mut Self, usize) -> T, { - let disr = self.read_usize()?; + let disr = self.read_usize(); f(self, disr) } #[inline] - fn read_enum_variant_arg<T, F>(&mut self, f: F) -> Result<T, Self::Error> + fn read_enum_variant_arg<T, F>(&mut self, f: F) -> T where - F: FnOnce(&mut Self) -> Result<T, Self::Error>, + F: FnOnce(&mut Self) -> T, { f(self) } #[inline] - fn read_struct<T, F>(&mut self, f: F) -> Result<T, Self::Error> + fn read_struct<T, F>(&mut self, f: F) -> T where - F: FnOnce(&mut Self) -> Result<T, Self::Error>, + F: FnOnce(&mut Self) -> T, { f(self) } #[inline] - fn read_struct_field<T, F>(&mut self, _f_name: &str, f: F) -> Result<T, Self::Error> + fn read_struct_field<T, F>(&mut self, _f_name: &str, f: F) -> T where - F: FnOnce(&mut Self) -> Result<T, Self::Error>, + F: FnOnce(&mut Self) -> T, { f(self) } #[inline] - fn read_tuple<T, F>(&mut self, _len: usize, f: F) -> Result<T, Self::Error> + fn read_tuple<T, F>(&mut self, _len: usize, f: F) -> T where - F: FnOnce(&mut Self) -> Result<T, Self::Error>, + F: FnOnce(&mut Self) -> T, { f(self) } #[inline] - fn read_tuple_arg<T, F>(&mut self, f: F) -> Result<T, Self::Error> + fn read_tuple_arg<T, F>(&mut self, f: F) -> T where - F: FnOnce(&mut Self) -> Result<T, Self::Error>, + F: FnOnce(&mut Self) -> T, { f(self) } // Specialized types: - fn read_option<T, F>(&mut self, mut f: F) -> Result<T, Self::Error> + fn read_option<T, F>(&mut self, mut f: F) -> T where - F: FnMut(&mut Self, bool) -> Result<T, Self::Error>, + F: FnMut(&mut Self, bool) -> T, { self.read_enum(move |this| { this.read_enum_variant(&["None", "Some"], move |this, idx| match idx { 0 => f(this, false), 1 => f(this, true), - _ => Err(this.error("read_option: expected 0 for None or 1 for Some")), + _ => panic!("read_option: expected 0 for None or 1 for Some"), }) }) } - fn read_seq<T, F>(&mut self, f: F) -> Result<T, Self::Error> + fn read_seq<T, F>(&mut self, f: F) -> T where - F: FnOnce(&mut Self, usize) -> Result<T, Self::Error>, + F: FnOnce(&mut Self, usize) -> T, { - let len = self.read_usize()?; + let len = self.read_usize(); f(self, len) } #[inline] - fn read_seq_elt<T, F>(&mut self, f: F) -> Result<T, Self::Error> + fn read_seq_elt<T, F>(&mut self, f: F) -> T where - F: FnOnce(&mut Self) -> Result<T, Self::Error>, + F: FnOnce(&mut Self) -> T, { f(self) } - fn read_map<T, F>(&mut self, f: F) -> Result<T, Self::Error> + fn read_map<T, F>(&mut self, f: F) -> T where - F: FnOnce(&mut Self, usize) -> Result<T, Self::Error>, + F: FnOnce(&mut Self, usize) -> T, { - let len = self.read_usize()?; + let len = self.read_usize(); f(self, len) } #[inline] - fn read_map_elt_key<T, F>(&mut self, f: F) -> Result<T, Self::Error> + fn read_map_elt_key<T, F>(&mut self, f: F) -> T where - F: FnOnce(&mut Self) -> Result<T, Self::Error>, + F: FnOnce(&mut Self) -> T, { f(self) } #[inline] - fn read_map_elt_val<T, F>(&mut self, f: F) -> Result<T, Self::Error> + fn read_map_elt_val<T, F>(&mut self, f: F) -> T where - F: FnOnce(&mut Self) -> Result<T, Self::Error>, + F: FnOnce(&mut Self) -> T, { f(self) } - - // Failure - fn error(&mut self, err: &str) -> Self::Error; } /// Trait for types that can be serialized @@ -340,7 +341,7 @@ pub trait Encodable<S: Encoder> { /// * `TyDecodable` should be used for types that are only serialized in crate /// metadata or the incremental cache. This is most types in `rustc_middle`. pub trait Decodable<D: Decoder>: Sized { - fn decode(d: &mut D) -> Result<Self, D::Error>; + fn decode(d: &mut D) -> Self; } macro_rules! direct_serialize_impls { @@ -353,7 +354,7 @@ macro_rules! direct_serialize_impls { } impl<D: Decoder> Decodable<D> for $ty { - fn decode(d: &mut D) -> Result<$ty, D::Error> { + fn decode(d: &mut D) -> $ty { d.$read_method() } } @@ -387,7 +388,7 @@ impl<S: Encoder> Encodable<S> for ! { } impl<D: Decoder> Decodable<D> for ! { - fn decode(_d: &mut D) -> Result<!, D::Error> { + fn decode(_d: &mut D) -> ! { unreachable!() } } @@ -399,8 +400,8 @@ impl<S: Encoder> Encodable<S> for ::std::num::NonZeroU32 { } impl<D: Decoder> Decodable<D> for ::std::num::NonZeroU32 { - fn decode(d: &mut D) -> Result<Self, D::Error> { - d.read_u32().map(|d| ::std::num::NonZeroU32::new(d).unwrap()) + fn decode(d: &mut D) -> Self { + ::std::num::NonZeroU32::new(d.read_u32()).unwrap() } } @@ -423,8 +424,8 @@ impl<S: Encoder> Encodable<S> for String { } impl<D: Decoder> Decodable<D> for String { - fn decode(d: &mut D) -> Result<String, D::Error> { - Ok(d.read_str()?.into_owned()) + fn decode(d: &mut D) -> String { + d.read_str().into_owned() } } @@ -435,7 +436,7 @@ impl<S: Encoder> Encodable<S> for () { } impl<D: Decoder> Decodable<D> for () { - fn decode(d: &mut D) -> Result<(), D::Error> { + fn decode(d: &mut D) -> () { d.read_unit() } } @@ -447,16 +448,16 @@ impl<S: Encoder, T> Encodable<S> for PhantomData<T> { } impl<D: Decoder, T> Decodable<D> for PhantomData<T> { - fn decode(d: &mut D) -> Result<PhantomData<T>, D::Error> { - d.read_unit()?; - Ok(PhantomData) + fn decode(d: &mut D) -> PhantomData<T> { + d.read_unit(); + PhantomData } } impl<D: Decoder, T: Decodable<D>> Decodable<D> for Box<[T]> { - fn decode(d: &mut D) -> Result<Box<[T]>, D::Error> { - let v: Vec<T> = Decodable::decode(d)?; - Ok(v.into_boxed_slice()) + fn decode(d: &mut D) -> Box<[T]> { + let v: Vec<T> = Decodable::decode(d); + v.into_boxed_slice() } } @@ -467,8 +468,8 @@ impl<S: Encoder, T: Encodable<S>> Encodable<S> for Rc<T> { } impl<D: Decoder, T: Decodable<D>> Decodable<D> for Rc<T> { - fn decode(d: &mut D) -> Result<Rc<T>, D::Error> { - Ok(Rc::new(Decodable::decode(d)?)) + fn decode(d: &mut D) -> Rc<T> { + Rc::new(Decodable::decode(d)) } } @@ -491,13 +492,22 @@ impl<S: Encoder, T: Encodable<S>> Encodable<S> for Vec<T> { } impl<D: Decoder, T: Decodable<D>> Decodable<D> for Vec<T> { - default fn decode(d: &mut D) -> Result<Vec<T>, D::Error> { + default fn decode(d: &mut D) -> Vec<T> { d.read_seq(|d, len| { - let mut v = Vec::with_capacity(len); - for _ in 0..len { - v.push(d.read_seq_elt(|d| Decodable::decode(d))?); + // SAFETY: we set the capacity in advance, only write elements, and + // only set the length at the end once the writing has succeeded. + let mut vec = Vec::with_capacity(len); + unsafe { + let ptr: *mut T = vec.as_mut_ptr(); + for i in 0..len { + std::ptr::write( + ptr.offset(i as isize), + d.read_seq_elt(|d| Decodable::decode(d)), + ); + } + vec.set_len(len); } - Ok(v) + vec }) } } @@ -510,14 +520,14 @@ impl<S: Encoder, T: Encodable<S>, const N: usize> Encodable<S> for [T; N] { } impl<D: Decoder, const N: usize> Decodable<D> for [u8; N] { - fn decode(d: &mut D) -> Result<[u8; N], D::Error> { + fn decode(d: &mut D) -> [u8; N] { d.read_seq(|d, len| { assert!(len == N); let mut v = [0u8; N]; for i in 0..len { - v[i] = d.read_seq_elt(|d| Decodable::decode(d))?; + v[i] = d.read_seq_elt(|d| Decodable::decode(d)); } - Ok(v) + v }) } } @@ -536,9 +546,9 @@ impl<D: Decoder, T: Decodable<D> + ToOwned> Decodable<D> for Cow<'static, [T]> where [T]: ToOwned<Owned = Vec<T>>, { - fn decode(d: &mut D) -> Result<Cow<'static, [T]>, D::Error> { - let v: Vec<T> = Decodable::decode(d)?; - Ok(Cow::Owned(v)) + fn decode(d: &mut D) -> Cow<'static, [T]> { + let v: Vec<T> = Decodable::decode(d); + Cow::Owned(v) } } @@ -552,8 +562,8 @@ impl<S: Encoder, T: Encodable<S>> Encodable<S> for Option<T> { } impl<D: Decoder, T: Decodable<D>> Decodable<D> for Option<T> { - fn decode(d: &mut D) -> Result<Option<T>, D::Error> { - d.read_option(|d, b| if b { Ok(Some(Decodable::decode(d)?)) } else { Ok(None) }) + fn decode(d: &mut D) -> Option<T> { + d.read_option(|d, b| if b { Some(Decodable::decode(d)) } else { None }) } } @@ -571,17 +581,12 @@ impl<S: Encoder, T1: Encodable<S>, T2: Encodable<S>> Encodable<S> for Result<T1, } impl<D: Decoder, T1: Decodable<D>, T2: Decodable<D>> Decodable<D> for Result<T1, T2> { - fn decode(d: &mut D) -> Result<Result<T1, T2>, D::Error> { + fn decode(d: &mut D) -> Result<T1, T2> { d.read_enum(|d| { d.read_enum_variant(&["Ok", "Err"], |d, disr| match disr { - 0 => Ok(Ok(d.read_enum_variant_arg(|d| T1::decode(d))?)), - 1 => Ok(Err(d.read_enum_variant_arg(|d| T2::decode(d))?)), - _ => { - panic!( - "Encountered invalid discriminant while \ - decoding `Result`." - ); - } + 0 => Ok(d.read_enum_variant_arg(|d| T1::decode(d))), + 1 => Err(d.read_enum_variant_arg(|d| T2::decode(d))), + _ => panic!("Encountered invalid discriminant while decoding `Result`."), }) }) } @@ -609,13 +614,13 @@ macro_rules! tuple { ( $($name:ident,)+ ) => ( impl<D: Decoder, $($name: Decodable<D>),+> Decodable<D> for ($($name,)+) { #[allow(non_snake_case)] - fn decode(d: &mut D) -> Result<($($name,)+), D::Error> { + fn decode(d: &mut D) -> ($($name,)+) { let len: usize = count!($($name)+); d.read_tuple(len, |d| { - let ret = ($(d.read_tuple_arg(|d| -> Result<$name, D::Error> { + let ret = ($(d.read_tuple_arg(|d| -> $name { Decodable::decode(d) - })?,)+); - Ok(ret) + }),)+); + ret }) } } @@ -651,9 +656,9 @@ impl<S: Encoder> Encodable<S> for path::PathBuf { } impl<D: Decoder> Decodable<D> for path::PathBuf { - fn decode(d: &mut D) -> Result<path::PathBuf, D::Error> { - let bytes: String = Decodable::decode(d)?; - Ok(path::PathBuf::from(bytes)) + fn decode(d: &mut D) -> path::PathBuf { + let bytes: String = Decodable::decode(d); + path::PathBuf::from(bytes) } } @@ -664,8 +669,8 @@ impl<S: Encoder, T: Encodable<S> + Copy> Encodable<S> for Cell<T> { } impl<D: Decoder, T: Decodable<D> + Copy> Decodable<D> for Cell<T> { - fn decode(d: &mut D) -> Result<Cell<T>, D::Error> { - Ok(Cell::new(Decodable::decode(d)?)) + fn decode(d: &mut D) -> Cell<T> { + Cell::new(Decodable::decode(d)) } } @@ -681,8 +686,8 @@ impl<S: Encoder, T: Encodable<S>> Encodable<S> for RefCell<T> { } impl<D: Decoder, T: Decodable<D>> Decodable<D> for RefCell<T> { - fn decode(d: &mut D) -> Result<RefCell<T>, D::Error> { - Ok(RefCell::new(Decodable::decode(d)?)) + fn decode(d: &mut D) -> RefCell<T> { + RefCell::new(Decodable::decode(d)) } } @@ -693,8 +698,8 @@ impl<S: Encoder, T: Encodable<S>> Encodable<S> for Arc<T> { } impl<D: Decoder, T: Decodable<D>> Decodable<D> for Arc<T> { - fn decode(d: &mut D) -> Result<Arc<T>, D::Error> { - Ok(Arc::new(Decodable::decode(d)?)) + fn decode(d: &mut D) -> Arc<T> { + Arc::new(Decodable::decode(d)) } } @@ -704,7 +709,7 @@ impl<S: Encoder, T: ?Sized + Encodable<S>> Encodable<S> for Box<T> { } } impl<D: Decoder, T: Decodable<D>> Decodable<D> for Box<T> { - fn decode(d: &mut D) -> Result<Box<T>, D::Error> { - Ok(Box::new(Decodable::decode(d)?)) + fn decode(d: &mut D) -> Box<T> { + Box::new(Decodable::decode(d)) } } diff --git a/compiler/rustc_serialize/tests/json.rs b/compiler/rustc_serialize/tests/json.rs index a759fa1bf1a..ede912bdfb6 100644 --- a/compiler/rustc_serialize/tests/json.rs +++ b/compiler/rustc_serialize/tests/json.rs @@ -1,14 +1,10 @@ #![allow(rustc::internal)] -use json::DecoderError::*; use json::ErrorCode::*; use json::Json::*; use json::JsonEvent::*; use json::ParserError::*; -use json::{ - from_str, DecodeResult, Decoder, DecoderError, Encoder, EncoderError, Json, JsonEvent, Parser, - StackElement, -}; +use json::{from_str, Decoder, Encoder, EncoderError, Json, JsonEvent, Parser, StackElement}; use rustc_macros::{Decodable, Encodable}; use rustc_serialize::json; use rustc_serialize::{Decodable, Encodable}; @@ -26,27 +22,27 @@ struct OptionData { #[test] fn test_decode_option_none() { let s = "{}"; - let obj: OptionData = json::decode(s).unwrap(); + let obj: OptionData = json::decode(s); assert_eq!(obj, OptionData { opt: None }); } #[test] fn test_decode_option_some() { let s = "{ \"opt\": 10 }"; - let obj: OptionData = json::decode(s).unwrap(); + let obj: OptionData = json::decode(s); assert_eq!(obj, OptionData { opt: Some(10) }); } #[test] -fn test_decode_option_malformed() { - check_err::<OptionData>( - "{ \"opt\": [] }", - ExpectedError("Number".to_string(), "[]".to_string()), - ); - check_err::<OptionData>( - "{ \"opt\": false }", - ExpectedError("Number".to_string(), "false".to_string()), - ); +#[should_panic(expected = r#"ExpectedError("Number", "[]")"#)] +fn test_decode_option_malformed1() { + check_err::<OptionData>(r#"{ "opt": [] }"#); +} + +#[test] +#[should_panic(expected = r#"ExpectedError("Number", "false")"#)] +fn test_decode_option_malformed2() { + check_err::<OptionData>(r#"{ "opt": false }"#); } #[derive(PartialEq, Encodable, Decodable, Debug)] @@ -329,13 +325,13 @@ fn test_read_identifiers() { #[test] fn test_decode_identifiers() { - let v: () = json::decode("null").unwrap(); + let v: () = json::decode("null"); assert_eq!(v, ()); - let v: bool = json::decode("true").unwrap(); + let v: bool = json::decode("true"); assert_eq!(v, true); - let v: bool = json::decode("false").unwrap(); + let v: bool = json::decode("false"); assert_eq!(v, false); } @@ -368,42 +364,42 @@ fn test_read_number() { } #[test] +#[should_panic(expected = r#"ExpectedError("Integer", "765.25")"#)] fn test_decode_numbers() { - let v: f64 = json::decode("3").unwrap(); + let v: f64 = json::decode("3"); assert_eq!(v, 3.0); - let v: f64 = json::decode("3.1").unwrap(); + let v: f64 = json::decode("3.1"); assert_eq!(v, 3.1); - let v: f64 = json::decode("-1.2").unwrap(); + let v: f64 = json::decode("-1.2"); assert_eq!(v, -1.2); - let v: f64 = json::decode("0.4").unwrap(); + let v: f64 = json::decode("0.4"); assert_eq!(v, 0.4); - let v: f64 = json::decode("0.4e5").unwrap(); + let v: f64 = json::decode("0.4e5"); assert_eq!(v, 0.4e5); - let v: f64 = json::decode("0.4e15").unwrap(); + let v: f64 = json::decode("0.4e15"); assert_eq!(v, 0.4e15); - let v: f64 = json::decode("0.4e-01").unwrap(); + let v: f64 = json::decode("0.4e-01"); assert_eq!(v, 0.4e-01); - let v: u64 = json::decode("0").unwrap(); + let v: u64 = json::decode("0"); assert_eq!(v, 0); - let v: u64 = json::decode("18446744073709551615").unwrap(); + let v: u64 = json::decode("18446744073709551615"); assert_eq!(v, u64::MAX); - let v: i64 = json::decode("-9223372036854775808").unwrap(); + let v: i64 = json::decode("-9223372036854775808"); assert_eq!(v, i64::MIN); - let v: i64 = json::decode("9223372036854775807").unwrap(); + let v: i64 = json::decode("9223372036854775807"); assert_eq!(v, i64::MAX); - let res: DecodeResult<i64> = json::decode("765.25"); - assert_eq!(res, Err(ExpectedError("Integer".to_string(), "765.25".to_string()))); + json::decode::<i64>("765.25"); } #[test] @@ -438,7 +434,7 @@ fn test_decode_str() { ]; for (i, o) in s { - let v: string::String = json::decode(i).unwrap(); + let v: string::String = json::decode(i); assert_eq!(v, o); } } @@ -463,39 +459,41 @@ fn test_read_array() { #[test] fn test_decode_array() { - let v: Vec<()> = json::decode("[]").unwrap(); + let v: Vec<()> = json::decode("[]"); assert_eq!(v, []); - let v: Vec<()> = json::decode("[null]").unwrap(); + let v: Vec<()> = json::decode("[null]"); assert_eq!(v, [()]); - let v: Vec<bool> = json::decode("[true]").unwrap(); + let v: Vec<bool> = json::decode("[true]"); assert_eq!(v, [true]); - let v: Vec<isize> = json::decode("[3, 1]").unwrap(); + let v: Vec<isize> = json::decode("[3, 1]"); assert_eq!(v, [3, 1]); - let v: Vec<Vec<usize>> = json::decode("[[3], [1, 2]]").unwrap(); + let v: Vec<Vec<usize>> = json::decode("[[3], [1, 2]]"); assert_eq!(v, [vec![3], vec![1, 2]]); } #[test] fn test_decode_tuple() { - let t: (usize, usize, usize) = json::decode("[1, 2, 3]").unwrap(); + let t: (usize, usize, usize) = json::decode("[1, 2, 3]"); assert_eq!(t, (1, 2, 3)); - let t: (usize, string::String) = json::decode("[1, \"two\"]").unwrap(); + let t: (usize, string::String) = json::decode("[1, \"two\"]"); assert_eq!(t, (1, "two".to_string())); } #[test] +#[should_panic] fn test_decode_tuple_malformed_types() { - assert!(json::decode::<(usize, string::String)>("[1, 2]").is_err()); + json::decode::<(usize, string::String)>("[1, 2]"); } #[test] +#[should_panic] fn test_decode_tuple_malformed_length() { - assert!(json::decode::<(usize, usize)>("[1, 2, 3]").is_err()); + json::decode::<(usize, usize)>("[1, 2, 3]"); } #[test] @@ -562,7 +560,7 @@ fn test_decode_struct() { ] }"; - let v: Outer = json::decode(s).unwrap(); + let v: Outer = json::decode(s); assert_eq!( v, Outer { inner: vec![Inner { a: (), b: 2, c: vec!["abc".to_string(), "xyz".to_string()] }] } @@ -577,7 +575,7 @@ struct FloatStruct { #[test] fn test_decode_struct_with_nan() { let s = "{\"f\":null,\"a\":[null,123]}"; - let obj: FloatStruct = json::decode(s).unwrap(); + let obj: FloatStruct = json::decode(s); assert!(obj.f.is_nan()); assert!(obj.a[0].is_nan()); assert_eq!(obj.a[1], 123f64); @@ -585,20 +583,20 @@ fn test_decode_struct_with_nan() { #[test] fn test_decode_option() { - let value: Option<string::String> = json::decode("null").unwrap(); + let value: Option<string::String> = json::decode("null"); assert_eq!(value, None); - let value: Option<string::String> = json::decode("\"jodhpurs\"").unwrap(); + let value: Option<string::String> = json::decode("\"jodhpurs\""); assert_eq!(value, Some("jodhpurs".to_string())); } #[test] fn test_decode_enum() { - let value: Animal = json::decode("\"Dog\"").unwrap(); + let value: Animal = json::decode("\"Dog\""); assert_eq!(value, Dog); let s = "{\"variant\":\"Frog\",\"fields\":[\"Henry\",349]}"; - let value: Animal = json::decode(s).unwrap(); + let value: Animal = json::decode(s); assert_eq!(value, Frog("Henry".to_string(), 349)); } @@ -606,7 +604,7 @@ fn test_decode_enum() { fn test_decode_map() { let s = "{\"a\": \"Dog\", \"b\": {\"variant\":\"Frog\",\ \"fields\":[\"Henry\", 349]}}"; - let mut map: BTreeMap<string::String, Animal> = json::decode(s).unwrap(); + let mut map: BTreeMap<string::String, Animal> = json::decode(s); assert_eq!(map.remove(&"a".to_string()), Some(Dog)); assert_eq!(map.remove(&"b".to_string()), Some(Frog("Henry".to_string(), 349))); @@ -630,59 +628,65 @@ enum DecodeEnum { A(f64), B(string::String), } -fn check_err<T: Decodable<Decoder>>(to_parse: &'static str, expected: DecoderError) { - let res: DecodeResult<T> = match from_str(to_parse) { - Err(e) => Err(ParseError(e)), - Ok(json) => Decodable::decode(&mut Decoder::new(json)), - }; - match res { - Ok(_) => panic!("`{:?}` parsed & decoded ok, expecting error `{:?}`", to_parse, expected), - Err(ParseError(e)) => panic!("`{:?}` is not valid json: {:?}", to_parse, e), - Err(e) => { - assert_eq!(e, expected); - } - } +fn check_err<T: Decodable<Decoder>>(to_parse: &str) { + let json = from_str(to_parse).unwrap(); + let _: T = Decodable::decode(&mut Decoder::new(json)); } #[test] -fn test_decode_errors_struct() { - check_err::<DecodeStruct>("[]", ExpectedError("Object".to_string(), "[]".to_string())); - check_err::<DecodeStruct>( - "{\"x\": true, \"y\": true, \"z\": \"\", \"w\": []}", - ExpectedError("Number".to_string(), "true".to_string()), - ); - check_err::<DecodeStruct>( - "{\"x\": 1, \"y\": [], \"z\": \"\", \"w\": []}", - ExpectedError("Boolean".to_string(), "[]".to_string()), - ); - check_err::<DecodeStruct>( - "{\"x\": 1, \"y\": true, \"z\": {}, \"w\": []}", - ExpectedError("String".to_string(), "{}".to_string()), - ); - check_err::<DecodeStruct>( - "{\"x\": 1, \"y\": true, \"z\": \"\", \"w\": null}", - ExpectedError("Array".to_string(), "null".to_string()), - ); - check_err::<DecodeStruct>( - "{\"x\": 1, \"y\": true, \"z\": \"\"}", - MissingFieldError("w".to_string()), - ); +#[should_panic(expected = r#"ExpectedError("Object", "[]")"#)] +fn test_decode_errors_struct1() { + check_err::<DecodeStruct>("[]"); } #[test] -fn test_decode_errors_enum() { - check_err::<DecodeEnum>("{}", MissingFieldError("variant".to_string())); - check_err::<DecodeEnum>( - "{\"variant\": 1}", - ExpectedError("String".to_string(), "1".to_string()), - ); - check_err::<DecodeEnum>("{\"variant\": \"A\"}", MissingFieldError("fields".to_string())); - check_err::<DecodeEnum>( - "{\"variant\": \"A\", \"fields\": null}", - ExpectedError("Array".to_string(), "null".to_string()), - ); - check_err::<DecodeEnum>( - "{\"variant\": \"C\", \"fields\": []}", - UnknownVariantError("C".to_string()), - ); +#[should_panic(expected = r#"ExpectedError("Number", "true")"#)] +fn test_decode_errors_struct2() { + check_err::<DecodeStruct>(r#"{"x": true, "y": true, "z": "", "w": []}"#); +} +#[test] +#[should_panic(expected = r#"ExpectedError("Boolean", "[]")"#)] +fn test_decode_errors_struct3() { + check_err::<DecodeStruct>(r#"{"x": 1, "y": [], "z": "", "w": []}"#); +} +#[test] +#[should_panic(expected = r#"ExpectedError("String", "{}")"#)] +fn test_decode_errors_struct4() { + check_err::<DecodeStruct>(r#"{"x": 1, "y": true, "z": {}, "w": []}"#); +} +#[test] +#[should_panic(expected = r#"ExpectedError("Array", "null")"#)] +fn test_decode_errors_struct5() { + check_err::<DecodeStruct>(r#"{"x": 1, "y": true, "z": "", "w": null}"#); +} +#[test] +#[should_panic(expected = r#"ExpectedError("Array", "null")"#)] +fn test_decode_errors_struct6() { + check_err::<DecodeStruct>(r#"{"x": 1, "y": true, "z": ""}"#); +} + +#[test] +#[should_panic(expected = r#"MissingFieldError("variant")"#)] +fn test_decode_errors_enum1() { + check_err::<DecodeEnum>(r#"{}"#); +} +#[test] +#[should_panic(expected = r#"ExpectedError("String", "1")"#)] +fn test_decode_errors_enum2() { + check_err::<DecodeEnum>(r#"{"variant": 1}"#); +} +#[test] +#[should_panic(expected = r#"MissingFieldError("fields")"#)] +fn test_decode_errors_enum3() { + check_err::<DecodeEnum>(r#"{"variant": "A"}"#); +} +#[test] +#[should_panic(expected = r#"ExpectedError("Array", "null")"#)] +fn test_decode_errors_enum4() { + check_err::<DecodeEnum>(r#"{"variant": "A", "fields": null}"#); +} +#[test] +#[should_panic(expected = r#"UnknownVariantError("C")"#)] +fn test_decode_errors_enum5() { + check_err::<DecodeEnum>(r#"{"variant": "C", "fields": []}"#); } #[test] @@ -944,7 +948,7 @@ fn test_hashmap_with_enum_key() { map.insert(Enum::Foo, 0); let result = json::encode(&map).unwrap(); assert_eq!(&result[..], r#"{"Foo":0}"#); - let decoded: HashMap<Enum, _> = json::decode(&result).unwrap(); + let decoded: HashMap<Enum, _> = json::decode(&result); assert_eq!(map, decoded); } @@ -957,10 +961,11 @@ fn test_hashmap_with_numeric_key_can_handle_double_quote_delimited_key() { Ok(o) => o, }; let mut decoder = Decoder::new(json_obj); - let _hm: HashMap<usize, bool> = Decodable::decode(&mut decoder).unwrap(); + let _hm: HashMap<usize, bool> = Decodable::decode(&mut decoder); } #[test] +#[should_panic(expected = r#"ExpectedError("Number", "a")"#)] fn test_hashmap_with_numeric_key_will_error_with_string_keys() { use std::collections::HashMap; let json_str = "{\"a\":true}"; @@ -969,8 +974,7 @@ fn test_hashmap_with_numeric_key_will_error_with_string_keys() { Ok(o) => o, }; let mut decoder = Decoder::new(json_obj); - let result: Result<HashMap<usize, bool>, DecoderError> = Decodable::decode(&mut decoder); - assert_eq!(result, Err(ExpectedError("Number".to_string(), "a".to_string()))); + let _: HashMap<usize, bool> = Decodable::decode(&mut decoder); } fn assert_stream_equal(src: &str, expected: Vec<(JsonEvent, Vec<StackElement<'_>>)>) { diff --git a/compiler/rustc_serialize/tests/opaque.rs b/compiler/rustc_serialize/tests/opaque.rs index 13b3676a56c..298eb115111 100644 --- a/compiler/rustc_serialize/tests/opaque.rs +++ b/compiler/rustc_serialize/tests/opaque.rs @@ -41,7 +41,7 @@ fn check_round_trip<T: Encodable<Encoder> + for<'a> Decodable<Decoder<'a>> + Par let mut decoder = Decoder::new(&data[..], 0); for value in values { - let decoded = Decodable::decode(&mut decoder).unwrap(); + let decoded = Decodable::decode(&mut decoder); assert_eq!(value, decoded); } } diff --git a/compiler/rustc_span/src/def_id.rs b/compiler/rustc_span/src/def_id.rs index 5390eed89fa..147c1f9e043 100644 --- a/compiler/rustc_span/src/def_id.rs +++ b/compiler/rustc_span/src/def_id.rs @@ -47,8 +47,8 @@ impl<E: Encoder> Encodable<E> for CrateNum { } impl<D: Decoder> Decodable<D> for CrateNum { - default fn decode(d: &mut D) -> Result<CrateNum, D::Error> { - Ok(CrateNum::from_u32(d.read_u32()?)) + default fn decode(d: &mut D) -> CrateNum { + CrateNum::from_u32(d.read_u32()) } } @@ -209,7 +209,7 @@ impl<E: Encoder> Encodable<E> for DefIndex { } impl<D: Decoder> Decodable<D> for DefIndex { - default fn decode(_: &mut D) -> Result<DefIndex, D::Error> { + default fn decode(_: &mut D) -> DefIndex { panic!("cannot decode `DefIndex` with `{}`", std::any::type_name::<D>()); } } @@ -298,12 +298,10 @@ impl<E: Encoder> Encodable<E> for DefId { } impl<D: Decoder> Decodable<D> for DefId { - default fn decode(d: &mut D) -> Result<DefId, D::Error> { - d.read_struct(|d| { - Ok(DefId { - krate: d.read_struct_field("krate", Decodable::decode)?, - index: d.read_struct_field("index", Decodable::decode)?, - }) + default fn decode(d: &mut D) -> DefId { + d.read_struct(|d| DefId { + krate: d.read_struct_field("krate", Decodable::decode), + index: d.read_struct_field("index", Decodable::decode), }) } } @@ -378,8 +376,8 @@ impl<E: Encoder> Encodable<E> for LocalDefId { } impl<D: Decoder> Decodable<D> for LocalDefId { - fn decode(d: &mut D) -> Result<LocalDefId, D::Error> { - DefId::decode(d).map(|d| d.expect_local()) + fn decode(d: &mut D) -> LocalDefId { + DefId::decode(d).expect_local() } } diff --git a/compiler/rustc_span/src/hygiene.rs b/compiler/rustc_span/src/hygiene.rs index 7b70c20d307..e0d6bd8cb7b 100644 --- a/compiler/rustc_span/src/hygiene.rs +++ b/compiler/rustc_span/src/hygiene.rs @@ -1314,19 +1314,16 @@ pub fn decode_expn_id( // to track which `SyntaxContext`s we have already decoded. // The provided closure will be invoked to deserialize a `SyntaxContextData` // if we haven't already seen the id of the `SyntaxContext` we are deserializing. -pub fn decode_syntax_context< - D: Decoder, - F: FnOnce(&mut D, u32) -> Result<SyntaxContextData, D::Error>, ->( +pub fn decode_syntax_context<D: Decoder, F: FnOnce(&mut D, u32) -> SyntaxContextData>( d: &mut D, context: &HygieneDecodeContext, decode_data: F, -) -> Result<SyntaxContext, D::Error> { - let raw_id: u32 = Decodable::decode(d)?; +) -> SyntaxContext { + let raw_id: u32 = Decodable::decode(d); if raw_id == 0 { debug!("decode_syntax_context: deserialized root"); // The root is special - return Ok(SyntaxContext::root()); + return SyntaxContext::root(); } let outer_ctxts = &context.remapped_ctxts; @@ -1334,7 +1331,7 @@ pub fn decode_syntax_context< // Ensure that the lock() temporary is dropped early { if let Some(ctxt) = outer_ctxts.lock().get(raw_id as usize).copied().flatten() { - return Ok(ctxt); + return ctxt; } } @@ -1364,7 +1361,7 @@ pub fn decode_syntax_context< // Don't try to decode data while holding the lock, since we need to // be able to recursively decode a SyntaxContext - let mut ctxt_data = decode_data(d, raw_id)?; + let mut ctxt_data = decode_data(d, raw_id); // Reset `dollar_crate_name` so that it will be updated by `update_dollar_crate_names` // We don't care what the encoding crate set this to - we want to resolve it // from the perspective of the current compilation session @@ -1380,7 +1377,7 @@ pub fn decode_syntax_context< assert_eq!(dummy.dollar_crate_name, kw::Empty); }); - Ok(new_ctxt) + new_ctxt } fn for_all_ctxts_in<E, F: FnMut(u32, SyntaxContext, &SyntaxContextData) -> Result<(), E>>( @@ -1422,13 +1419,13 @@ impl<E: Encoder> Encodable<E> for ExpnId { } impl<D: Decoder> Decodable<D> for LocalExpnId { - fn decode(d: &mut D) -> Result<Self, D::Error> { - ExpnId::decode(d).map(ExpnId::expect_local) + fn decode(d: &mut D) -> Self { + ExpnId::expect_local(ExpnId::decode(d)) } } impl<D: Decoder> Decodable<D> for ExpnId { - default fn decode(_: &mut D) -> Result<Self, D::Error> { + default fn decode(_: &mut D) -> Self { panic!("cannot decode `ExpnId` with `{}`", std::any::type_name::<D>()); } } @@ -1451,7 +1448,7 @@ impl<E: Encoder> Encodable<E> for SyntaxContext { } impl<D: Decoder> Decodable<D> for SyntaxContext { - default fn decode(_: &mut D) -> Result<Self, D::Error> { + default fn decode(_: &mut D) -> Self { panic!("cannot decode `SyntaxContext` with `{}`", std::any::type_name::<D>()); } } diff --git a/compiler/rustc_span/src/lib.rs b/compiler/rustc_span/src/lib.rs index 9602bc5d0b7..92360164a01 100644 --- a/compiler/rustc_span/src/lib.rs +++ b/compiler/rustc_span/src/lib.rs @@ -975,12 +975,12 @@ impl<E: Encoder> Encodable<E> for Span { } } impl<D: Decoder> Decodable<D> for Span { - default fn decode(s: &mut D) -> Result<Span, D::Error> { + default fn decode(s: &mut D) -> Span { s.read_struct(|d| { - let lo = d.read_struct_field("lo", Decodable::decode)?; - let hi = d.read_struct_field("hi", Decodable::decode)?; + let lo = d.read_struct_field("lo", Decodable::decode); + let hi = d.read_struct_field("hi", Decodable::decode); - Ok(Span::new(lo, hi, SyntaxContext::root(), None)) + Span::new(lo, hi, SyntaxContext::root(), None) }) } } @@ -1448,30 +1448,30 @@ impl<S: Encoder> Encodable<S> for SourceFile { } impl<D: Decoder> Decodable<D> for SourceFile { - fn decode(d: &mut D) -> Result<SourceFile, D::Error> { + fn decode(d: &mut D) -> SourceFile { d.read_struct(|d| { - let name: FileName = d.read_struct_field("name", |d| Decodable::decode(d))?; + let name: FileName = d.read_struct_field("name", |d| Decodable::decode(d)); let src_hash: SourceFileHash = - d.read_struct_field("src_hash", |d| Decodable::decode(d))?; - let start_pos: BytePos = d.read_struct_field("start_pos", |d| Decodable::decode(d))?; - let end_pos: BytePos = d.read_struct_field("end_pos", |d| Decodable::decode(d))?; + d.read_struct_field("src_hash", |d| Decodable::decode(d)); + let start_pos: BytePos = d.read_struct_field("start_pos", |d| Decodable::decode(d)); + let end_pos: BytePos = d.read_struct_field("end_pos", |d| Decodable::decode(d)); let lines: Vec<BytePos> = d.read_struct_field("lines", |d| { - let num_lines: u32 = Decodable::decode(d)?; + let num_lines: u32 = Decodable::decode(d); let mut lines = Vec::with_capacity(num_lines as usize); if num_lines > 0 { // Read the number of bytes used per diff. - let bytes_per_diff: u8 = Decodable::decode(d)?; + let bytes_per_diff: u8 = Decodable::decode(d); // Read the first element. - let mut line_start: BytePos = Decodable::decode(d)?; + let mut line_start: BytePos = Decodable::decode(d); lines.push(line_start); for _ in 1..num_lines { let diff = match bytes_per_diff { - 1 => d.read_u8()? as u32, - 2 => d.read_u16()? as u32, - 4 => d.read_u32()?, + 1 => d.read_u8() as u32, + 2 => d.read_u16() as u32, + 4 => d.read_u32(), _ => unreachable!(), }; @@ -1481,17 +1481,17 @@ impl<D: Decoder> Decodable<D> for SourceFile { } } - Ok(lines) - })?; + lines + }); let multibyte_chars: Vec<MultiByteChar> = - d.read_struct_field("multibyte_chars", |d| Decodable::decode(d))?; + d.read_struct_field("multibyte_chars", |d| Decodable::decode(d)); let non_narrow_chars: Vec<NonNarrowChar> = - d.read_struct_field("non_narrow_chars", |d| Decodable::decode(d))?; - let name_hash: u128 = d.read_struct_field("name_hash", |d| Decodable::decode(d))?; + d.read_struct_field("non_narrow_chars", |d| Decodable::decode(d)); + let name_hash: u128 = d.read_struct_field("name_hash", |d| Decodable::decode(d)); let normalized_pos: Vec<NormalizedPos> = - d.read_struct_field("normalized_pos", |d| Decodable::decode(d))?; - let cnum: CrateNum = d.read_struct_field("cnum", |d| Decodable::decode(d))?; - Ok(SourceFile { + d.read_struct_field("normalized_pos", |d| Decodable::decode(d)); + let cnum: CrateNum = d.read_struct_field("cnum", |d| Decodable::decode(d)); + SourceFile { name, start_pos, end_pos, @@ -1506,7 +1506,7 @@ impl<D: Decoder> Decodable<D> for SourceFile { normalized_pos, name_hash, cnum, - }) + } }) } } @@ -1949,8 +1949,8 @@ impl<S: rustc_serialize::Encoder> Encodable<S> for BytePos { } impl<D: rustc_serialize::Decoder> Decodable<D> for BytePos { - fn decode(d: &mut D) -> Result<BytePos, D::Error> { - Ok(BytePos(d.read_u32()?)) + fn decode(d: &mut D) -> BytePos { + BytePos(d.read_u32()) } } diff --git a/compiler/rustc_span/src/symbol.rs b/compiler/rustc_span/src/symbol.rs index 702e3594660..42fe05b52cc 100644 --- a/compiler/rustc_span/src/symbol.rs +++ b/compiler/rustc_span/src/symbol.rs @@ -1755,8 +1755,8 @@ impl<S: Encoder> Encodable<S> for Symbol { impl<D: Decoder> Decodable<D> for Symbol { #[inline] - fn decode(d: &mut D) -> Result<Symbol, D::Error> { - Ok(Symbol::intern(&d.read_str()?)) + fn decode(d: &mut D) -> Symbol { + Symbol::intern(&d.read_str()) } } diff --git a/src/librustdoc/scrape_examples.rs b/src/librustdoc/scrape_examples.rs index 47fc666da9a..899c9e4c629 100644 --- a/src/librustdoc/scrape_examples.rs +++ b/src/librustdoc/scrape_examples.rs @@ -292,7 +292,7 @@ crate fn load_call_locations( for path in with_examples { let bytes = fs::read(&path).map_err(|e| format!("{} (for path {})", e, path))?; let mut decoder = Decoder::new(&bytes, 0); - let calls = AllCallLocations::decode(&mut decoder)?; + let calls = AllCallLocations::decode(&mut decoder); for (function, fn_calls) in calls.into_iter() { all_calls.entry(function).or_default().extend(fn_calls.into_iter()); diff --git a/src/test/ui-fulldeps/deriving-encodable-decodable-box.rs b/src/test/ui-fulldeps/deriving-encodable-decodable-box.rs index fab2031d952..dd20eef0700 100644 --- a/src/test/ui-fulldeps/deriving-encodable-decodable-box.rs +++ b/src/test/ui-fulldeps/deriving-encodable-decodable-box.rs @@ -18,6 +18,6 @@ struct A { fn main() { let obj = A { foo: Box::new([true, false]) }; let s = json::encode(&obj).unwrap(); - let obj2: A = json::decode(&s).unwrap(); + let obj2: A = json::decode(&s); assert_eq!(obj.foo, obj2.foo); } diff --git a/src/test/ui-fulldeps/deriving-encodable-decodable-cell-refcell.rs b/src/test/ui-fulldeps/deriving-encodable-decodable-cell-refcell.rs index 9dedf990f25..18aa974c31d 100644 --- a/src/test/ui-fulldeps/deriving-encodable-decodable-cell-refcell.rs +++ b/src/test/ui-fulldeps/deriving-encodable-decodable-cell-refcell.rs @@ -27,7 +27,7 @@ struct B { fn main() { let obj = B { foo: Cell::new(true), bar: RefCell::new(A { baz: 2 }) }; let s = json::encode(&obj).unwrap(); - let obj2: B = json::decode(&s).unwrap(); + let obj2: B = json::decode(&s); assert_eq!(obj.foo.get(), obj2.foo.get()); assert_eq!(obj.bar.borrow().baz, obj2.bar.borrow().baz); } diff --git a/src/test/ui-fulldeps/issue-14021.rs b/src/test/ui-fulldeps/issue-14021.rs index be88a593962..acd75170d68 100644 --- a/src/test/ui-fulldeps/issue-14021.rs +++ b/src/test/ui-fulldeps/issue-14021.rs @@ -20,7 +20,7 @@ pub fn main() { let json_object = json::from_str(&json_str); let mut decoder = json::Decoder::new(json_object.unwrap()); - let mut decoded_obj: UnitLikeStruct = Decodable::decode(&mut decoder).unwrap(); + let mut decoded_obj: UnitLikeStruct = Decodable::decode(&mut decoder); assert_eq!(obj, decoded_obj); } diff --git a/src/test/ui-fulldeps/issue-4016.rs b/src/test/ui-fulldeps/issue-4016.rs index 4fd192497a0..65dab8d7704 100644 --- a/src/test/ui-fulldeps/issue-4016.rs +++ b/src/test/ui-fulldeps/issue-4016.rs @@ -12,7 +12,7 @@ trait JD: Decodable<json::Decoder> {} fn exec<T: JD>() { let doc = json::from_str("").unwrap(); let mut decoder = json::Decoder::new(doc); - let _v: T = Decodable::decode(&mut decoder).unwrap(); + let _v: T = Decodable::decode(&mut decoder); panic!() } diff --git a/src/test/ui-fulldeps/issue-4036.rs b/src/test/ui-fulldeps/issue-4036.rs index 05a7a30140a..702bb2d6ef6 100644 --- a/src/test/ui-fulldeps/issue-4036.rs +++ b/src/test/ui-fulldeps/issue-4036.rs @@ -13,5 +13,5 @@ use rustc_serialize::{json, Decodable}; pub fn main() { let json = json::from_str("[1]").unwrap(); let mut decoder = json::Decoder::new(json); - let _x: Vec<isize> = Decodable::decode(&mut decoder).unwrap(); + let _x: Vec<isize> = Decodable::decode(&mut decoder); } |