diff options
Diffstat (limited to 'third_party/rust/serde_derive/src/internals')
| -rw-r--r-- | third_party/rust/serde_derive/src/internals/ast.rs | 216 | ||||
| -rw-r--r-- | third_party/rust/serde_derive/src/internals/attr.rs | 1881 | ||||
| -rw-r--r-- | third_party/rust/serde_derive/src/internals/case.rs | 200 | ||||
| -rw-r--r-- | third_party/rust/serde_derive/src/internals/check.rs | 477 | ||||
| -rw-r--r-- | third_party/rust/serde_derive/src/internals/ctxt.rs | 68 | ||||
| -rw-r--r-- | third_party/rust/serde_derive/src/internals/mod.rs | 27 | ||||
| -rw-r--r-- | third_party/rust/serde_derive/src/internals/receiver.rs | 292 | ||||
| -rw-r--r-- | third_party/rust/serde_derive/src/internals/respan.rs | 16 | ||||
| -rw-r--r-- | third_party/rust/serde_derive/src/internals/symbol.rs | 71 |
9 files changed, 3248 insertions, 0 deletions
diff --git a/third_party/rust/serde_derive/src/internals/ast.rs b/third_party/rust/serde_derive/src/internals/ast.rs new file mode 100644 index 0000000000..a28d3ae7e9 --- /dev/null +++ b/third_party/rust/serde_derive/src/internals/ast.rs @@ -0,0 +1,216 @@ +//! A Serde ast, parsed from the Syn ast and ready to generate Rust code. + +use crate::internals::{attr, check, Ctxt, Derive}; +use syn::punctuated::Punctuated; +use syn::Token; + +/// A source data structure annotated with `#[derive(Serialize)]` and/or `#[derive(Deserialize)]`, +/// parsed into an internal representation. +pub struct Container<'a> { + /// The struct or enum name (without generics). + pub ident: syn::Ident, + /// Attributes on the structure, parsed for Serde. + pub attrs: attr::Container, + /// The contents of the struct or enum. + pub data: Data<'a>, + /// Any generics on the struct or enum. + pub generics: &'a syn::Generics, + /// Original input. + pub original: &'a syn::DeriveInput, +} + +/// The fields of a struct or enum. +/// +/// Analogous to `syn::Data`. +pub enum Data<'a> { + Enum(Vec<Variant<'a>>), + Struct(Style, Vec<Field<'a>>), +} + +/// A variant of an enum. +pub struct Variant<'a> { + pub ident: syn::Ident, + pub attrs: attr::Variant, + pub style: Style, + pub fields: Vec<Field<'a>>, + pub original: &'a syn::Variant, +} + +/// A field of a struct. +pub struct Field<'a> { + pub member: syn::Member, + pub attrs: attr::Field, + pub ty: &'a syn::Type, + pub original: &'a syn::Field, +} + +#[derive(Copy, Clone)] +pub enum Style { + /// Named fields. + Struct, + /// Many unnamed fields. + Tuple, + /// One unnamed field. + Newtype, + /// No fields. + Unit, +} + +impl<'a> Container<'a> { + /// Convert the raw Syn ast into a parsed container object, collecting errors in `cx`. + pub fn from_ast( + cx: &Ctxt, + item: &'a syn::DeriveInput, + derive: Derive, + ) -> Option<Container<'a>> { + let mut attrs = attr::Container::from_ast(cx, item); + + let mut data = match &item.data { + syn::Data::Enum(data) => Data::Enum(enum_from_ast(cx, &data.variants, attrs.default())), + syn::Data::Struct(data) => { + let (style, fields) = struct_from_ast(cx, &data.fields, None, attrs.default()); + Data::Struct(style, fields) + } + syn::Data::Union(_) => { + cx.error_spanned_by(item, "Serde does not support derive for unions"); + return None; + } + }; + + let mut has_flatten = false; + match &mut data { + Data::Enum(variants) => { + for variant in variants { + variant.attrs.rename_by_rules(attrs.rename_all_rules()); + for field in &mut variant.fields { + if field.attrs.flatten() { + has_flatten = true; + } + field.attrs.rename_by_rules( + variant + .attrs + .rename_all_rules() + .or(attrs.rename_all_fields_rules()), + ); + } + } + } + Data::Struct(_, fields) => { + for field in fields { + if field.attrs.flatten() { + has_flatten = true; + } + field.attrs.rename_by_rules(attrs.rename_all_rules()); + } + } + } + + if has_flatten { + attrs.mark_has_flatten(); + } + + let mut item = Container { + ident: item.ident.clone(), + attrs, + data, + generics: &item.generics, + original: item, + }; + check::check(cx, &mut item, derive); + Some(item) + } +} + +impl<'a> Data<'a> { + pub fn all_fields(&'a self) -> Box<dyn Iterator<Item = &'a Field<'a>> + 'a> { + match self { + Data::Enum(variants) => { + Box::new(variants.iter().flat_map(|variant| variant.fields.iter())) + } + Data::Struct(_, fields) => Box::new(fields.iter()), + } + } + + pub fn has_getter(&self) -> bool { + self.all_fields().any(|f| f.attrs.getter().is_some()) + } +} + +fn enum_from_ast<'a>( + cx: &Ctxt, + variants: &'a Punctuated<syn::Variant, Token![,]>, + container_default: &attr::Default, +) -> Vec<Variant<'a>> { + let variants: Vec<Variant> = variants + .iter() + .map(|variant| { + let attrs = attr::Variant::from_ast(cx, variant); + let (style, fields) = + struct_from_ast(cx, &variant.fields, Some(&attrs), container_default); + Variant { + ident: variant.ident.clone(), + attrs, + style, + fields, + original: variant, + } + }) + .collect(); + + let index_of_last_tagged_variant = variants + .iter() + .rposition(|variant| !variant.attrs.untagged()); + if let Some(index_of_last_tagged_variant) = index_of_last_tagged_variant { + for variant in &variants[..index_of_last_tagged_variant] { + if variant.attrs.untagged() { + cx.error_spanned_by(&variant.ident, "all variants with the #[serde(untagged)] attribute must be placed at the end of the enum"); + } + } + } + + variants +} + +fn struct_from_ast<'a>( + cx: &Ctxt, + fields: &'a syn::Fields, + attrs: Option<&attr::Variant>, + container_default: &attr::Default, +) -> (Style, Vec<Field<'a>>) { + match fields { + syn::Fields::Named(fields) => ( + Style::Struct, + fields_from_ast(cx, &fields.named, attrs, container_default), + ), + syn::Fields::Unnamed(fields) if fields.unnamed.len() == 1 => ( + Style::Newtype, + fields_from_ast(cx, &fields.unnamed, attrs, container_default), + ), + syn::Fields::Unnamed(fields) => ( + Style::Tuple, + fields_from_ast(cx, &fields.unnamed, attrs, container_default), + ), + syn::Fields::Unit => (Style::Unit, Vec::new()), + } +} + +fn fields_from_ast<'a>( + cx: &Ctxt, + fields: &'a Punctuated<syn::Field, Token![,]>, + attrs: Option<&attr::Variant>, + container_default: &attr::Default, +) -> Vec<Field<'a>> { + fields + .iter() + .enumerate() + .map(|(i, field)| Field { + member: match &field.ident { + Some(ident) => syn::Member::Named(ident.clone()), + None => syn::Member::Unnamed(i.into()), + }, + attrs: attr::Field::from_ast(cx, i, field, attrs, container_default), + ty: &field.ty, + original: field, + }) + .collect() +} diff --git a/third_party/rust/serde_derive/src/internals/attr.rs b/third_party/rust/serde_derive/src/internals/attr.rs new file mode 100644 index 0000000000..bb9de328a6 --- /dev/null +++ b/third_party/rust/serde_derive/src/internals/attr.rs @@ -0,0 +1,1881 @@ +use crate::internals::symbol::*; +use crate::internals::{ungroup, Ctxt}; +use proc_macro2::{Spacing, Span, TokenStream, TokenTree}; +use quote::ToTokens; +use std::borrow::Cow; +use std::collections::BTreeSet; +use std::iter::FromIterator; +use syn::meta::ParseNestedMeta; +use syn::parse::ParseStream; +use syn::punctuated::Punctuated; +use syn::{parse_quote, token, Ident, Lifetime, Token}; + +// This module handles parsing of `#[serde(...)]` attributes. The entrypoints +// are `attr::Container::from_ast`, `attr::Variant::from_ast`, and +// `attr::Field::from_ast`. Each returns an instance of the corresponding +// struct. Note that none of them return a Result. Unrecognized, malformed, or +// duplicated attributes result in a span_err but otherwise are ignored. The +// user will see errors simultaneously for all bad attributes in the crate +// rather than just the first. + +pub use crate::internals::case::RenameRule; + +struct Attr<'c, T> { + cx: &'c Ctxt, + name: Symbol, + tokens: TokenStream, + value: Option<T>, +} + +impl<'c, T> Attr<'c, T> { + fn none(cx: &'c Ctxt, name: Symbol) -> Self { + Attr { + cx, + name, + tokens: TokenStream::new(), + value: None, + } + } + + fn set<A: ToTokens>(&mut self, obj: A, value: T) { + let tokens = obj.into_token_stream(); + + if self.value.is_some() { + let msg = format!("duplicate serde attribute `{}`", self.name); + self.cx.error_spanned_by(tokens, msg); + } else { + self.tokens = tokens; + self.value = Some(value); + } + } + + fn set_opt<A: ToTokens>(&mut self, obj: A, value: Option<T>) { + if let Some(value) = value { + self.set(obj, value); + } + } + + fn set_if_none(&mut self, value: T) { + if self.value.is_none() { + self.value = Some(value); + } + } + + fn get(self) -> Option<T> { + self.value + } + + fn get_with_tokens(self) -> Option<(TokenStream, T)> { + match self.value { + Some(v) => Some((self.tokens, v)), + None => None, + } + } +} + +struct BoolAttr<'c>(Attr<'c, ()>); + +impl<'c> BoolAttr<'c> { + fn none(cx: &'c Ctxt, name: Symbol) -> Self { + BoolAttr(Attr::none(cx, name)) + } + + fn set_true<A: ToTokens>(&mut self, obj: A) { + self.0.set(obj, ()); + } + + fn get(&self) -> bool { + self.0.value.is_some() + } +} + +struct VecAttr<'c, T> { + cx: &'c Ctxt, + name: Symbol, + first_dup_tokens: TokenStream, + values: Vec<T>, +} + +impl<'c, T> VecAttr<'c, T> { + fn none(cx: &'c Ctxt, name: Symbol) -> Self { + VecAttr { + cx, + name, + first_dup_tokens: TokenStream::new(), + values: Vec::new(), + } + } + + fn insert<A: ToTokens>(&mut self, obj: A, value: T) { + if self.values.len() == 1 { + self.first_dup_tokens = obj.into_token_stream(); + } + self.values.push(value); + } + + fn at_most_one(mut self) -> Option<T> { + if self.values.len() > 1 { + let dup_token = self.first_dup_tokens; + let msg = format!("duplicate serde attribute `{}`", self.name); + self.cx.error_spanned_by(dup_token, msg); + None + } else { + self.values.pop() + } + } + + fn get(self) -> Vec<T> { + self.values + } +} + +pub struct Name { + serialize: String, + serialize_renamed: bool, + deserialize: String, + deserialize_renamed: bool, + deserialize_aliases: BTreeSet<String>, +} + +fn unraw(ident: &Ident) -> String { + ident.to_string().trim_start_matches("r#").to_owned() +} + +impl Name { + fn from_attrs( + source_name: String, + ser_name: Attr<String>, + de_name: Attr<String>, + de_aliases: Option<VecAttr<String>>, + ) -> Name { + let mut alias_set = BTreeSet::new(); + if let Some(de_aliases) = de_aliases { + for alias_name in de_aliases.get() { + alias_set.insert(alias_name); + } + } + + let ser_name = ser_name.get(); + let ser_renamed = ser_name.is_some(); + let de_name = de_name.get(); + let de_renamed = de_name.is_some(); + Name { + serialize: ser_name.unwrap_or_else(|| source_name.clone()), + serialize_renamed: ser_renamed, + deserialize: de_name.unwrap_or(source_name), + deserialize_renamed: de_renamed, + deserialize_aliases: alias_set, + } + } + + /// Return the container name for the container when serializing. + pub fn serialize_name(&self) -> &str { + &self.serialize + } + + /// Return the container name for the container when deserializing. + pub fn deserialize_name(&self) -> &str { + &self.deserialize + } + + fn deserialize_aliases(&self) -> &BTreeSet<String> { + &self.deserialize_aliases + } +} + +#[derive(Copy, Clone)] +pub struct RenameAllRules { + serialize: RenameRule, + deserialize: RenameRule, +} + +impl RenameAllRules { + /// Returns a new `RenameAllRules` with the individual rules of `self` and + /// `other_rules` joined by `RenameRules::or`. + pub fn or(self, other_rules: Self) -> Self { + Self { + serialize: self.serialize.or(other_rules.serialize), + deserialize: self.deserialize.or(other_rules.deserialize), + } + } +} + +/// Represents struct or enum attribute information. +pub struct Container { + name: Name, + transparent: bool, + deny_unknown_fields: bool, + default: Default, + rename_all_rules: RenameAllRules, + rename_all_fields_rules: RenameAllRules, + ser_bound: Option<Vec<syn::WherePredicate>>, + de_bound: Option<Vec<syn::WherePredicate>>, + tag: TagType, + type_from: Option<syn::Type>, + type_try_from: Option<syn::Type>, + type_into: Option<syn::Type>, + remote: Option<syn::Path>, + identifier: Identifier, + has_flatten: bool, + serde_path: Option<syn::Path>, + is_packed: bool, + /// Error message generated when type can't be deserialized + expecting: Option<String>, + non_exhaustive: bool, +} + +/// Styles of representing an enum. +pub enum TagType { + /// The default. + /// + /// ```json + /// {"variant1": {"key1": "value1", "key2": "value2"}} + /// ``` + External, + + /// `#[serde(tag = "type")]` + /// + /// ```json + /// {"type": "variant1", "key1": "value1", "key2": "value2"} + /// ``` + Internal { tag: String }, + + /// `#[serde(tag = "t", content = "c")]` + /// + /// ```json + /// {"t": "variant1", "c": {"key1": "value1", "key2": "value2"}} + /// ``` + Adjacent { tag: String, content: String }, + + /// `#[serde(untagged)]` + /// + /// ```json + /// {"key1": "value1", "key2": "value2"} + /// ``` + None, +} + +/// Whether this enum represents the fields of a struct or the variants of an +/// enum. +#[derive(Copy, Clone)] +pub enum Identifier { + /// It does not. + No, + + /// This enum represents the fields of a struct. All of the variants must be + /// unit variants, except possibly one which is annotated with + /// `#[serde(other)]` and is a newtype variant. + Field, + + /// This enum represents the variants of an enum. All of the variants must + /// be unit variants. + Variant, +} + +impl Identifier { + #[cfg(feature = "deserialize_in_place")] + pub fn is_some(self) -> bool { + match self { + Identifier::No => false, + Identifier::Field | Identifier::Variant => true, + } + } +} + +impl Container { + /// Extract out the `#[serde(...)]` attributes from an item. + pub fn from_ast(cx: &Ctxt, item: &syn::DeriveInput) -> Self { + let mut ser_name = Attr::none(cx, RENAME); + let mut de_name = Attr::none(cx, RENAME); + let mut transparent = BoolAttr::none(cx, TRANSPARENT); + let mut deny_unknown_fields = BoolAttr::none(cx, DENY_UNKNOWN_FIELDS); + let mut default = Attr::none(cx, DEFAULT); + let mut rename_all_ser_rule = Attr::none(cx, RENAME_ALL); + let mut rename_all_de_rule = Attr::none(cx, RENAME_ALL); + let mut rename_all_fields_ser_rule = Attr::none(cx, RENAME_ALL_FIELDS); + let mut rename_all_fields_de_rule = Attr::none(cx, RENAME_ALL_FIELDS); + let mut ser_bound = Attr::none(cx, BOUND); + let mut de_bound = Attr::none(cx, BOUND); + let mut untagged = BoolAttr::none(cx, UNTAGGED); + let mut internal_tag = Attr::none(cx, TAG); + let mut content = Attr::none(cx, CONTENT); + let mut type_from = Attr::none(cx, FROM); + let mut type_try_from = Attr::none(cx, TRY_FROM); + let mut type_into = Attr::none(cx, INTO); + let mut remote = Attr::none(cx, REMOTE); + let mut field_identifier = BoolAttr::none(cx, FIELD_IDENTIFIER); + let mut variant_identifier = BoolAttr::none(cx, VARIANT_IDENTIFIER); + let mut serde_path = Attr::none(cx, CRATE); + let mut expecting = Attr::none(cx, EXPECTING); + let mut non_exhaustive = false; + + for attr in &item.attrs { + if attr.path() != SERDE { + non_exhaustive |= + matches!(&attr.meta, syn::Meta::Path(path) if path == NON_EXHAUSTIVE); + continue; + } + + if let syn::Meta::List(meta) = &attr.meta { + if meta.tokens.is_empty() { + continue; + } + } + + if let Err(err) = attr.parse_nested_meta(|meta| { + if meta.path == RENAME { + // #[serde(rename = "foo")] + // #[serde(rename(serialize = "foo", deserialize = "bar"))] + let (ser, de) = get_renames(cx, RENAME, &meta)?; + ser_name.set_opt(&meta.path, ser.as_ref().map(syn::LitStr::value)); + de_name.set_opt(&meta.path, de.as_ref().map(syn::LitStr::value)); + } else if meta.path == RENAME_ALL { + // #[serde(rename_all = "foo")] + // #[serde(rename_all(serialize = "foo", deserialize = "bar"))] + let one_name = meta.input.peek(Token![=]); + let (ser, de) = get_renames(cx, RENAME_ALL, &meta)?; + if let Some(ser) = ser { + match RenameRule::from_str(&ser.value()) { + Ok(rename_rule) => rename_all_ser_rule.set(&meta.path, rename_rule), + Err(err) => cx.error_spanned_by(ser, err), + } + } + if let Some(de) = de { + match RenameRule::from_str(&de.value()) { + Ok(rename_rule) => rename_all_de_rule.set(&meta.path, rename_rule), + Err(err) => { + if !one_name { + cx.error_spanned_by(de, err); + } + } + } + } + } else if meta.path == RENAME_ALL_FIELDS { + // #[serde(rename_all_fields = "foo")] + // #[serde(rename_all_fields(serialize = "foo", deserialize = "bar"))] + let one_name = meta.input.peek(Token![=]); + let (ser, de) = get_renames(cx, RENAME_ALL_FIELDS, &meta)?; + + match item.data { + syn::Data::Enum(_) => { + if let Some(ser) = ser { + match RenameRule::from_str(&ser.value()) { + Ok(rename_rule) => { + rename_all_fields_ser_rule.set(&meta.path, rename_rule); + } + Err(err) => cx.error_spanned_by(ser, err), + } + } + if let Some(de) = de { + match RenameRule::from_str(&de.value()) { + Ok(rename_rule) => { + rename_all_fields_de_rule.set(&meta.path, rename_rule); + } + Err(err) => { + if !one_name { + cx.error_spanned_by(de, err); + } + } + } + } + } + syn::Data::Struct(_) => { + let msg = "#[serde(rename_all_fields)] can only be used on enums"; + cx.syn_error(meta.error(msg)); + } + syn::Data::Union(_) => { + let msg = "#[serde(rename_all_fields)] can only be used on enums"; + cx.syn_error(meta.error(msg)); + } + } + } else if meta.path == TRANSPARENT { + // #[serde(transparent)] + transparent.set_true(meta.path); + } else if meta.path == DENY_UNKNOWN_FIELDS { + // #[serde(deny_unknown_fields)] + deny_unknown_fields.set_true(meta.path); + } else if meta.path == DEFAULT { + if meta.input.peek(Token![=]) { + // #[serde(default = "...")] + if let Some(path) = parse_lit_into_expr_path(cx, DEFAULT, &meta)? { + match &item.data { + syn::Data::Struct(syn::DataStruct { fields, .. }) => match fields { + syn::Fields::Named(_) | syn::Fields::Unnamed(_) => { + default.set(&meta.path, Default::Path(path)); + } + syn::Fields::Unit => { + let msg = "#[serde(default = \"...\")] can only be used on structs that have fields"; + cx.syn_error(meta.error(msg)); + } + }, + syn::Data::Enum(_) => { + let msg = "#[serde(default = \"...\")] can only be used on structs"; + cx.syn_error(meta.error(msg)); + } + syn::Data::Union(_) => { + let msg = "#[serde(default = \"...\")] can only be used on structs"; + cx.syn_error(meta.error(msg)); + } + } + } + } else { + // #[serde(default)] + match &item.data { + syn::Data::Struct(syn::DataStruct { fields, .. }) => match fields { + syn::Fields::Named(_) | syn::Fields::Unnamed(_) => { + default.set(meta.path, Default::Default); + } + syn::Fields::Unit => { + let msg = "#[serde(default)] can only be used on structs that have fields"; + cx.error_spanned_by(fields, msg); + } + }, + syn::Data::Enum(_) => { + let msg = "#[serde(default)] can only be used on structs"; + cx.syn_error(meta.error(msg)); + } + syn::Data::Union(_) => { + let msg = "#[serde(default)] can only be used on structs"; + cx.syn_error(meta.error(msg)); + } + } + } + } else if meta.path == BOUND { + // #[serde(bound = "T: SomeBound")] + // #[serde(bound(serialize = "...", deserialize = "..."))] + let (ser, de) = get_where_predicates(cx, &meta)?; + ser_bound.set_opt(&meta.path, ser); + de_bound.set_opt(&meta.path, de); + } else if meta.path == UNTAGGED { + // #[serde(untagged)] + match item.data { + syn::Data::Enum(_) => { + untagged.set_true(&meta.path); + } + syn::Data::Struct(_) => { + let msg = "#[serde(untagged)] can only be used on enums"; + cx.syn_error(meta.error(msg)); + } + syn::Data::Union(_) => { + let msg = "#[serde(untagged)] can only be used on enums"; + cx.syn_error(meta.error(msg)); + } + } + } else if meta.path == TAG { + // #[serde(tag = "type")] + if let Some(s) = get_lit_str(cx, TAG, &meta)? { + match &item.data { + syn::Data::Enum(_) => { + internal_tag.set(&meta.path, s.value()); + } + syn::Data::Struct(syn::DataStruct { fields, .. }) => match fields { + syn::Fields::Named(_) => { + internal_tag.set(&meta.path, s.value()); + } + syn::Fields::Unnamed(_) | syn::Fields::Unit => { + let msg = "#[serde(tag = \"...\")] can only be used on enums and structs with named fields"; + cx.syn_error(meta.error(msg)); + } + }, + syn::Data::Union(_) => { + let msg = "#[serde(tag = \"...\")] can only be used on enums and structs with named fields"; + cx.syn_error(meta.error(msg)); + } + } + } + } else if meta.path == CONTENT { + // #[serde(content = "c")] + if let Some(s) = get_lit_str(cx, CONTENT, &meta)? { + match &item.data { + syn::Data::Enum(_) => { + content.set(&meta.path, s.value()); + } + syn::Data::Struct(_) => { + let msg = "#[serde(content = \"...\")] can only be used on enums"; + cx.syn_error(meta.error(msg)); + } + syn::Data::Union(_) => { + let msg = "#[serde(content = \"...\")] can only be used on enums"; + cx.syn_error(meta.error(msg)); + } + } + } + } else if meta.path == FROM { + // #[serde(from = "Type")] + if let Some(from_ty) = parse_lit_into_ty(cx, FROM, &meta)? { + type_from.set_opt(&meta.path, Some(from_ty)); + } + } else if meta.path == TRY_FROM { + // #[serde(try_from = "Type")] + if let Some(try_from_ty) = parse_lit_into_ty(cx, TRY_FROM, &meta)? { + type_try_from.set_opt(&meta.path, Some(try_from_ty)); + } + } else if meta.path == INTO { + // #[serde(into = "Type")] + if let Some(into_ty) = parse_lit_into_ty(cx, INTO, &meta)? { + type_into.set_opt(&meta.path, Some(into_ty)); + } + } else if meta.path == REMOTE { + // #[serde(remote = "...")] + if let Some(path) = parse_lit_into_path(cx, REMOTE, &meta)? { + if is_primitive_path(&path, "Self") { + remote.set(&meta.path, item.ident.clone().into()); + } else { + remote.set(&meta.path, path); + } + } + } else if meta.path == FIELD_IDENTIFIER { + // #[serde(field_identifier)] + field_identifier.set_true(&meta.path); + } else if meta.path == VARIANT_IDENTIFIER { + // #[serde(variant_identifier)] + variant_identifier.set_true(&meta.path); + } else if meta.path == CRATE { + // #[serde(crate = "foo")] + if let Some(path) = parse_lit_into_path(cx, CRATE, &meta)? { + serde_path.set(&meta.path, path); + } + } else if meta.path == EXPECTING { + // #[serde(expecting = "a message")] + if let Some(s) = get_lit_str(cx, EXPECTING, &meta)? { + expecting.set(&meta.path, s.value()); + } + } else { + let path = meta.path.to_token_stream().to_string().replace(' ', ""); + return Err( + meta.error(format_args!("unknown serde container attribute `{}`", path)) + ); + } + Ok(()) + }) { + cx.syn_error(err); + } + } + + let mut is_packed = false; + for attr in &item.attrs { + if attr.path() == REPR { + let _ = attr.parse_args_with(|input: ParseStream| { + while let Some(token) = input.parse()? { + if let TokenTree::Ident(ident) = token { + is_packed |= ident == "packed"; + } + } + Ok(()) + }); + } + } + + Container { + name: Name::from_attrs(unraw(&item.ident), ser_name, de_name, None), + transparent: transparent.get(), + deny_unknown_fields: deny_unknown_fields.get(), + default: default.get().unwrap_or(Default::None), + rename_all_rules: RenameAllRules { + serialize: rename_all_ser_rule.get().unwrap_or(RenameRule::None), + deserialize: rename_all_de_rule.get().unwrap_or(RenameRule::None), + }, + rename_all_fields_rules: RenameAllRules { + serialize: rename_all_fields_ser_rule.get().unwrap_or(RenameRule::None), + deserialize: rename_all_fields_de_rule.get().unwrap_or(RenameRule::None), + }, + ser_bound: ser_bound.get(), + de_bound: de_bound.get(), + tag: decide_tag(cx, item, untagged, internal_tag, content), + type_from: type_from.get(), + type_try_from: type_try_from.get(), + type_into: type_into.get(), + remote: remote.get(), + identifier: decide_identifier(cx, item, field_identifier, variant_identifier), + has_flatten: false, + serde_path: serde_path.get(), + is_packed, + expecting: expecting.get(), + non_exhaustive, + } + } + + pub fn name(&self) -> &Name { + &self.name + } + + pub fn rename_all_rules(&self) -> RenameAllRules { + self.rename_all_rules + } + + pub fn rename_all_fields_rules(&self) -> RenameAllRules { + self.rename_all_fields_rules + } + + pub fn transparent(&self) -> bool { + self.transparent + } + + pub fn deny_unknown_fields(&self) -> bool { + self.deny_unknown_fields + } + + pub fn default(&self) -> &Default { + &self.default + } + + pub fn ser_bound(&self) -> Option<&[syn::WherePredicate]> { + self.ser_bound.as_ref().map(|vec| &vec[..]) + } + + pub fn de_bound(&self) -> Option<&[syn::WherePredicate]> { + self.de_bound.as_ref().map(|vec| &vec[..]) + } + + pub fn tag(&self) -> &TagType { + &self.tag + } + + pub fn type_from(&self) -> Option<&syn::Type> { + self.type_from.as_ref() + } + + pub fn type_try_from(&self) -> Option<&syn::Type> { + self.type_try_from.as_ref() + } + + pub fn type_into(&self) -> Option<&syn::Type> { + self.type_into.as_ref() + } + + pub fn remote(&self) -> Option<&syn::Path> { + self.remote.as_ref() + } + + pub fn is_packed(&self) -> bool { + self.is_packed + } + + pub fn identifier(&self) -> Identifier { + self.identifier + } + + pub fn has_flatten(&self) -> bool { + self.has_flatten + } + + pub fn mark_has_flatten(&mut self) { + self.has_flatten = true; + } + + pub fn custom_serde_path(&self) -> Option<&syn::Path> { + self.serde_path.as_ref() + } + + pub fn serde_path(&self) -> Cow<syn::Path> { + self.custom_serde_path() + .map_or_else(|| Cow::Owned(parse_quote!(_serde)), Cow::Borrowed) + } + + /// Error message generated when type can't be deserialized. + /// If `None`, default message will be used + pub fn expecting(&self) -> Option<&str> { + self.expecting.as_ref().map(String::as_ref) + } + + pub fn non_exhaustive(&self) -> bool { + self.non_exhaustive + } +} + +fn decide_tag( + cx: &Ctxt, + item: &syn::DeriveInput, + untagged: BoolAttr, + internal_tag: Attr<String>, + content: Attr<String>, +) -> TagType { + match ( + untagged.0.get_with_tokens(), + internal_tag.get_with_tokens(), + content.get_with_tokens(), + ) { + (None, None, None) => TagType::External, + (Some(_), None, None) => TagType::None, + (None, Some((_, tag)), None) => { + // Check that there are no tuple variants. + if let syn::Data::Enum(data) = &item.data { + for variant in &data.variants { + match &variant.fields { + syn::Fields::Named(_) | syn::Fields::Unit => {} + syn::Fields::Unnamed(fields) => { + if fields.unnamed.len() != 1 { + let msg = + "#[serde(tag = \"...\")] cannot be used with tuple variants"; + cx.error_spanned_by(variant, msg); + break; + } + } + } + } + } + TagType::Internal { tag } + } + (Some((untagged_tokens, ())), Some((tag_tokens, _)), None) => { + let msg = "enum cannot be both untagged and internally tagged"; + cx.error_spanned_by(untagged_tokens, msg); + cx.error_spanned_by(tag_tokens, msg); + TagType::External // doesn't matter, will error + } + (None, None, Some((content_tokens, _))) => { + let msg = "#[serde(tag = \"...\", content = \"...\")] must be used together"; + cx.error_spanned_by(content_tokens, msg); + TagType::External + } + (Some((untagged_tokens, ())), None, Some((content_tokens, _))) => { + let msg = "untagged enum cannot have #[serde(content = \"...\")]"; + cx.error_spanned_by(untagged_tokens, msg); + cx.error_spanned_by(content_tokens, msg); + TagType::External + } + (None, Some((_, tag)), Some((_, content))) => TagType::Adjacent { tag, content }, + (Some((untagged_tokens, ())), Some((tag_tokens, _)), Some((content_tokens, _))) => { + let msg = "untagged enum cannot have #[serde(tag = \"...\", content = \"...\")]"; + cx.error_spanned_by(untagged_tokens, msg); + cx.error_spanned_by(tag_tokens, msg); + cx.error_spanned_by(content_tokens, msg); + TagType::External + } + } +} + +fn decide_identifier( + cx: &Ctxt, + item: &syn::DeriveInput, + field_identifier: BoolAttr, + variant_identifier: BoolAttr, +) -> Identifier { + match ( + &item.data, + field_identifier.0.get_with_tokens(), + variant_identifier.0.get_with_tokens(), + ) { + (_, None, None) => Identifier::No, + (_, Some((field_identifier_tokens, ())), Some((variant_identifier_tokens, ()))) => { + let msg = + "#[serde(field_identifier)] and #[serde(variant_identifier)] cannot both be set"; + cx.error_spanned_by(field_identifier_tokens, msg); + cx.error_spanned_by(variant_identifier_tokens, msg); + Identifier::No + } + (syn::Data::Enum(_), Some(_), None) => Identifier::Field, + (syn::Data::Enum(_), None, Some(_)) => Identifier::Variant, + (syn::Data::Struct(syn::DataStruct { struct_token, .. }), Some(_), None) => { + let msg = "#[serde(field_identifier)] can only be used on an enum"; + cx.error_spanned_by(struct_token, msg); + Identifier::No + } + (syn::Data::Union(syn::DataUnion { union_token, .. }), Some(_), None) => { + let msg = "#[serde(field_identifier)] can only be used on an enum"; + cx.error_spanned_by(union_token, msg); + Identifier::No + } + (syn::Data::Struct(syn::DataStruct { struct_token, .. }), None, Some(_)) => { + let msg = "#[serde(variant_identifier)] can only be used on an enum"; + cx.error_spanned_by(struct_token, msg); + Identifier::No + } + (syn::Data::Union(syn::DataUnion { union_token, .. }), None, Some(_)) => { + let msg = "#[serde(variant_identifier)] can only be used on an enum"; + cx.error_spanned_by(union_token, msg); + Identifier::No + } + } +} + +/// Represents variant attribute information +pub struct Variant { + name: Name, + rename_all_rules: RenameAllRules, + ser_bound: Option<Vec<syn::WherePredicate>>, + de_bound: Option<Vec<syn::WherePredicate>>, + skip_deserializing: bool, + skip_serializing: bool, + other: bool, + serialize_with: Option<syn::ExprPath>, + deserialize_with: Option<syn::ExprPath>, + borrow: Option<BorrowAttribute>, + untagged: bool, +} + +struct BorrowAttribute { + path: syn::Path, + lifetimes: Option<BTreeSet<syn::Lifetime>>, +} + +impl Variant { + pub fn from_ast(cx: &Ctxt, variant: &syn::Variant) -> Self { + let mut ser_name = Attr::none(cx, RENAME); + let mut de_name = Attr::none(cx, RENAME); + let mut de_aliases = VecAttr::none(cx, RENAME); + let mut skip_deserializing = BoolAttr::none(cx, SKIP_DESERIALIZING); + let mut skip_serializing = BoolAttr::none(cx, SKIP_SERIALIZING); + let mut rename_all_ser_rule = Attr::none(cx, RENAME_ALL); + let mut rename_all_de_rule = Attr::none(cx, RENAME_ALL); + let mut ser_bound = Attr::none(cx, BOUND); + let mut de_bound = Attr::none(cx, BOUND); + let mut other = BoolAttr::none(cx, OTHER); + let mut serialize_with = Attr::none(cx, SERIALIZE_WITH); + let mut deserialize_with = Attr::none(cx, DESERIALIZE_WITH); + let mut borrow = Attr::none(cx, BORROW); + let mut untagged = BoolAttr::none(cx, UNTAGGED); + + for attr in &variant.attrs { + if attr.path() != SERDE { + continue; + } + + if let syn::Meta::List(meta) = &attr.meta { + if meta.tokens.is_empty() { + continue; + } + } + + if let Err(err) = attr.parse_nested_meta(|meta| { + if meta.path == RENAME { + // #[serde(rename = "foo")] + // #[serde(rename(serialize = "foo", deserialize = "bar"))] + let (ser, de) = get_multiple_renames(cx, &meta)?; + ser_name.set_opt(&meta.path, ser.as_ref().map(syn::LitStr::value)); + for de_value in de { + de_name.set_if_none(de_value.value()); + de_aliases.insert(&meta.path, de_value.value()); + } + } else if meta.path == ALIAS { + // #[serde(alias = "foo")] + if let Some(s) = get_lit_str(cx, ALIAS, &meta)? { + de_aliases.insert(&meta.path, s.value()); + } + } else if meta.path == RENAME_ALL { + // #[serde(rename_all = "foo")] + // #[serde(rename_all(serialize = "foo", deserialize = "bar"))] + let one_name = meta.input.peek(Token![=]); + let (ser, de) = get_renames(cx, RENAME_ALL, &meta)?; + if let Some(ser) = ser { + match RenameRule::from_str(&ser.value()) { + Ok(rename_rule) => rename_all_ser_rule.set(&meta.path, rename_rule), + Err(err) => cx.error_spanned_by(ser, err), + } + } + if let Some(de) = de { + match RenameRule::from_str(&de.value()) { + Ok(rename_rule) => rename_all_de_rule.set(&meta.path, rename_rule), + Err(err) => { + if !one_name { + cx.error_spanned_by(de, err); + } + } + } + } + } else if meta.path == SKIP { + // #[serde(skip)] + skip_serializing.set_true(&meta.path); + skip_deserializing.set_true(&meta.path); + } else if meta.path == SKIP_DESERIALIZING { + // #[serde(skip_deserializing)] + skip_deserializing.set_true(&meta.path); + } else if meta.path == SKIP_SERIALIZING { + // #[serde(skip_serializing)] + skip_serializing.set_true(&meta.path); + } else if meta.path == OTHER { + // #[serde(other)] + other.set_true(&meta.path); + } else if meta.path == BOUND { + // #[serde(bound = "T: SomeBound")] + // #[serde(bound(serialize = "...", deserialize = "..."))] + let (ser, de) = get_where_predicates(cx, &meta)?; + ser_bound.set_opt(&meta.path, ser); + de_bound.set_opt(&meta.path, de); + } else if meta.path == WITH { + // #[serde(with = "...")] + if let Some(path) = parse_lit_into_expr_path(cx, WITH, &meta)? { + let mut ser_path = path.clone(); + ser_path + .path + .segments + .push(Ident::new("serialize", Span::call_site()).into()); + serialize_with.set(&meta.path, ser_path); + let mut de_path = path; + de_path + .path + .segments + .push(Ident::new("deserialize", Span::call_site()).into()); + deserialize_with.set(&meta.path, de_path); + } + } else if meta.path == SERIALIZE_WITH { + // #[serde(serialize_with = "...")] + if let Some(path) = parse_lit_into_expr_path(cx, SERIALIZE_WITH, &meta)? { + serialize_with.set(&meta.path, path); + } + } else if meta.path == DESERIALIZE_WITH { + // #[serde(deserialize_with = "...")] + if let Some(path) = parse_lit_into_expr_path(cx, DESERIALIZE_WITH, &meta)? { + deserialize_with.set(&meta.path, path); + } + } else if meta.path == BORROW { + let borrow_attribute = if meta.input.peek(Token![=]) { + // #[serde(borrow = "'a + 'b")] + let lifetimes = parse_lit_into_lifetimes(cx, &meta)?; + BorrowAttribute { + path: meta.path.clone(), + lifetimes: Some(lifetimes), + } + } else { + // #[serde(borrow)] + BorrowAttribute { + path: meta.path.clone(), + lifetimes: None, + } + }; + match &variant.fields { + syn::Fields::Unnamed(fields) if fields.unnamed.len() == 1 => { + borrow.set(&meta.path, borrow_attribute); + } + _ => { + let msg = "#[serde(borrow)] may only be used on newtype variants"; + cx.error_spanned_by(variant, msg); + } + } + } else if meta.path == UNTAGGED { + untagged.set_true(&meta.path); + } else { + let path = meta.path.to_token_stream().to_string().replace(' ', ""); + return Err( + meta.error(format_args!("unknown serde variant attribute `{}`", path)) + ); + } + Ok(()) + }) { + cx.syn_error(err); + } + } + + Variant { + name: Name::from_attrs(unraw(&variant.ident), ser_name, de_name, Some(de_aliases)), + rename_all_rules: RenameAllRules { + serialize: rename_all_ser_rule.get().unwrap_or(RenameRule::None), + deserialize: rename_all_de_rule.get().unwrap_or(RenameRule::None), + }, + ser_bound: ser_bound.get(), + de_bound: de_bound.get(), + skip_deserializing: skip_deserializing.get(), + skip_serializing: skip_serializing.get(), + other: other.get(), + serialize_with: serialize_with.get(), + deserialize_with: deserialize_with.get(), + borrow: borrow.get(), + untagged: untagged.get(), + } + } + + pub fn name(&self) -> &Name { + &self.name + } + + pub fn aliases(&self) -> &BTreeSet<String> { + self.name.deserialize_aliases() + } + + pub fn rename_by_rules(&mut self, rules: RenameAllRules) { + if !self.name.serialize_renamed { + self.name.serialize = rules.serialize.apply_to_variant(&self.name.serialize); + } + if !self.name.deserialize_renamed { + self.name.deserialize = rules.deserialize.apply_to_variant(&self.name.deserialize); + } + self.name + .deserialize_aliases + .insert(self.name.deserialize.clone()); + } + + pub fn rename_all_rules(&self) -> RenameAllRules { + self.rename_all_rules + } + + pub fn ser_bound(&self) -> Option<&[syn::WherePredicate]> { + self.ser_bound.as_ref().map(|vec| &vec[..]) + } + + pub fn de_bound(&self) -> Option<&[syn::WherePredicate]> { + self.de_bound.as_ref().map(|vec| &vec[..]) + } + + pub fn skip_deserializing(&self) -> bool { + self.skip_deserializing + } + + pub fn skip_serializing(&self) -> bool { + self.skip_serializing + } + + pub fn other(&self) -> bool { + self.other + } + + pub fn serialize_with(&self) -> Option<&syn::ExprPath> { + self.serialize_with.as_ref() + } + + pub fn deserialize_with(&self) -> Option<&syn::ExprPath> { + self.deserialize_with.as_ref() + } + + pub fn untagged(&self) -> bool { + self.untagged + } +} + +/// Represents field attribute information +pub struct Field { + name: Name, + skip_serializing: bool, + skip_deserializing: bool, + skip_serializing_if: Option<syn::ExprPath>, + default: Default, + serialize_with: Option<syn::ExprPath>, + deserialize_with: Option<syn::ExprPath>, + ser_bound: Option<Vec<syn::WherePredicate>>, + de_bound: Option<Vec<syn::WherePredicate>>, + borrowed_lifetimes: BTreeSet<syn::Lifetime>, + getter: Option<syn::ExprPath>, + flatten: bool, + transparent: bool, +} + +/// Represents the default to use for a field when deserializing. +pub enum Default { + /// Field must always be specified because it does not have a default. + None, + /// The default is given by `std::default::Default::default()`. + Default, + /// The default is given by this function. + Path(syn::ExprPath), +} + +impl Default { + pub fn is_none(&self) -> bool { + match self { + Default::None => true, + Default::Default | Default::Path(_) => false, + } + } +} + +impl Field { + /// Extract out the `#[serde(...)]` attributes from a struct field. + pub fn from_ast( + cx: &Ctxt, + index: usize, + field: &syn::Field, + attrs: Option<&Variant>, + container_default: &Default, + ) -> Self { + let mut ser_name = Attr::none(cx, RENAME); + let mut de_name = Attr::none(cx, RENAME); + let mut de_aliases = VecAttr::none(cx, RENAME); + let mut skip_serializing = BoolAttr::none(cx, SKIP_SERIALIZING); + let mut skip_deserializing = BoolAttr::none(cx, SKIP_DESERIALIZING); + let mut skip_serializing_if = Attr::none(cx, SKIP_SERIALIZING_IF); + let mut default = Attr::none(cx, DEFAULT); + let mut serialize_with = Attr::none(cx, SERIALIZE_WITH); + let mut deserialize_with = Attr::none(cx, DESERIALIZE_WITH); + let mut ser_bound = Attr::none(cx, BOUND); + let mut de_bound = Attr::none(cx, BOUND); + let mut borrowed_lifetimes = Attr::none(cx, BORROW); + let mut getter = Attr::none(cx, GETTER); + let mut flatten = BoolAttr::none(cx, FLATTEN); + + let ident = match &field.ident { + Some(ident) => unraw(ident), + None => index.to_string(), + }; + + if let Some(borrow_attribute) = attrs.and_then(|variant| variant.borrow.as_ref()) { + if let Ok(borrowable) = borrowable_lifetimes(cx, &ident, field) { + if let Some(lifetimes) = &borrow_attribute.lifetimes { + for lifetime in lifetimes { + if !borrowable.contains(lifetime) { + let msg = + format!("field `{}` does not have lifetime {}", ident, lifetime); + cx.error_spanned_by(field, msg); + } + } + borrowed_lifetimes.set(&borrow_attribute.path, lifetimes.clone()); + } else { + borrowed_lifetimes.set(&borrow_attribute.path, borrowable); + } + } + } + + for attr in &field.attrs { + if attr.path() != SERDE { + continue; + } + + if let syn::Meta::List(meta) = &attr.meta { + if meta.tokens.is_empty() { + continue; + } + } + + if let Err(err) = attr.parse_nested_meta(|meta| { + if meta.path == RENAME { + // #[serde(rename = "foo")] + // #[serde(rename(serialize = "foo", deserialize = "bar"))] + let (ser, de) = get_multiple_renames(cx, &meta)?; + ser_name.set_opt(&meta.path, ser.as_ref().map(syn::LitStr::value)); + for de_value in de { + de_name.set_if_none(de_value.value()); + de_aliases.insert(&meta.path, de_value.value()); + } + } else if meta.path == ALIAS { + // #[serde(alias = "foo")] + if let Some(s) = get_lit_str(cx, ALIAS, &meta)? { + de_aliases.insert(&meta.path, s.value()); + } + } else if meta.path == DEFAULT { + if meta.input.peek(Token![=]) { + // #[serde(default = "...")] + if let Some(path) = parse_lit_into_expr_path(cx, DEFAULT, &meta)? { + default.set(&meta.path, Default::Path(path)); + } + } else { + // #[serde(default)] + default.set(&meta.path, Default::Default); + } + } else if meta.path == SKIP_SERIALIZING { + // #[serde(skip_serializing)] + skip_serializing.set_true(&meta.path); + } else if meta.path == SKIP_DESERIALIZING { + // #[serde(skip_deserializing)] + skip_deserializing.set_true(&meta.path); + } else if meta.path == SKIP { + // #[serde(skip)] + skip_serializing.set_true(&meta.path); + skip_deserializing.set_true(&meta.path); + } else if meta.path == SKIP_SERIALIZING_IF { + // #[serde(skip_serializing_if = "...")] + if let Some(path) = parse_lit_into_expr_path(cx, SKIP_SERIALIZING_IF, &meta)? { + skip_serializing_if.set(&meta.path, path); + } + } else if meta.path == SERIALIZE_WITH { + // #[serde(serialize_with = "...")] + if let Some(path) = parse_lit_into_expr_path(cx, SERIALIZE_WITH, &meta)? { + serialize_with.set(&meta.path, path); + } + } else if meta.path == DESERIALIZE_WITH { + // #[serde(deserialize_with = "...")] + if let Some(path) = parse_lit_into_expr_path(cx, DESERIALIZE_WITH, &meta)? { + deserialize_with.set(&meta.path, path); + } + } else if meta.path == WITH { + // #[serde(with = "...")] + if let Some(path) = parse_lit_into_expr_path(cx, WITH, &meta)? { + let mut ser_path = path.clone(); + ser_path + .path + .segments + .push(Ident::new("serialize", Span::call_site()).into()); + serialize_with.set(&meta.path, ser_path); + let mut de_path = path; + de_path + .path + .segments + .push(Ident::new("deserialize", Span::call_site()).into()); + deserialize_with.set(&meta.path, de_path); + } + } else if meta.path == BOUND { + // #[serde(bound = "T: SomeBound")] + // #[serde(bound(serialize = "...", deserialize = "..."))] + let (ser, de) = get_where_predicates(cx, &meta)?; + ser_bound.set_opt(&meta.path, ser); + de_bound.set_opt(&meta.path, de); + } else if meta.path == BORROW { + if meta.input.peek(Token![=]) { + // #[serde(borrow = "'a + 'b")] + let lifetimes = parse_lit_into_lifetimes(cx, &meta)?; + if let Ok(borrowable) = borrowable_lifetimes(cx, &ident, field) { + for lifetime in &lifetimes { + if !borrowable.contains(lifetime) { + let msg = format!( + "field `{}` does not have lifetime {}", + ident, lifetime, + ); + cx.error_spanned_by(field, msg); + } + } + borrowed_lifetimes.set(&meta.path, lifetimes); + } + } else { + // #[serde(borrow)] + if let Ok(borrowable) = borrowable_lifetimes(cx, &ident, field) { + borrowed_lifetimes.set(&meta.path, borrowable); + } + } + } else if meta.path == GETTER { + // #[serde(getter = "...")] + if let Some(path) = parse_lit_into_expr_path(cx, GETTER, &meta)? { + getter.set(&meta.path, path); + } + } else if meta.path == FLATTEN { + // #[serde(flatten)] + flatten.set_true(&meta.path); + } else { + let path = meta.path.to_token_stream().to_string().replace(' ', ""); + return Err( + meta.error(format_args!("unknown serde field attribute `{}`", path)) + ); + } + Ok(()) + }) { + cx.syn_error(err); + } + } + + // Is skip_deserializing, initialize the field to Default::default() unless a + // different default is specified by `#[serde(default = "...")]` on + // ourselves or our container (e.g. the struct we are in). + if let Default::None = *container_default { + if skip_deserializing.0.value.is_some() { + default.set_if_none(Default::Default); + } + } + + let mut borrowed_lifetimes = borrowed_lifetimes.get().unwrap_or_default(); + if !borrowed_lifetimes.is_empty() { + // Cow<str> and Cow<[u8]> never borrow by default: + // + // impl<'de, 'a, T: ?Sized> Deserialize<'de> for Cow<'a, T> + // + // A #[serde(borrow)] attribute enables borrowing that corresponds + // roughly to these impls: + // + // impl<'de: 'a, 'a> Deserialize<'de> for Cow<'a, str> + // impl<'de: 'a, 'a> Deserialize<'de> for Cow<'a, [u8]> + if is_cow(&field.ty, is_str) { + let mut path = syn::Path { + leading_colon: None, + segments: Punctuated::new(), + }; + let span = Span::call_site(); + path.segments.push(Ident::new("_serde", span).into()); + path.segments.push(Ident::new("__private", span).into()); + path.segments.push(Ident::new("de", span).into()); + path.segments + .push(Ident::new("borrow_cow_str", span).into()); + let expr = syn::ExprPath { + attrs: Vec::new(), + qself: None, + path, + }; + deserialize_with.set_if_none(expr); + } else if is_cow(&field.ty, is_slice_u8) { + let mut path = syn::Path { + leading_colon: None, + segments: Punctuated::new(), + }; + let span = Span::call_site(); + path.segments.push(Ident::new("_serde", span).into()); + path.segments.push(Ident::new("__private", span).into()); + path.segments.push(Ident::new("de", span).into()); + path.segments + .push(Ident::new("borrow_cow_bytes", span).into()); + let expr = syn::ExprPath { + attrs: Vec::new(), + qself: None, + path, + }; + deserialize_with.set_if_none(expr); + } + } else if is_implicitly_borrowed(&field.ty) { + // Types &str and &[u8] are always implicitly borrowed. No need for + // a #[serde(borrow)]. + collect_lifetimes(&field.ty, &mut borrowed_lifetimes); + } + + Field { + name: Name::from_attrs(ident, ser_name, de_name, Some(de_aliases)), + skip_serializing: skip_serializing.get(), + skip_deserializing: skip_deserializing.get(), + skip_serializing_if: skip_serializing_if.get(), + default: default.get().unwrap_or(Default::None), + serialize_with: serialize_with.get(), + deserialize_with: deserialize_with.get(), + ser_bound: ser_bound.get(), + de_bound: de_bound.get(), + borrowed_lifetimes, + getter: getter.get(), + flatten: flatten.get(), + transparent: false, + } + } + + pub fn name(&self) -> &Name { + &self.name + } + + pub fn aliases(&self) -> &BTreeSet<String> { + self.name.deserialize_aliases() + } + + pub fn rename_by_rules(&mut self, rules: RenameAllRules) { + if !self.name.serialize_renamed { + self.name.serialize = rules.serialize.apply_to_field(&self.name.serialize); + } + if !self.name.deserialize_renamed { + self.name.deserialize = rules.deserialize.apply_to_field(&self.name.deserialize); + } + self.name + .deserialize_aliases + .insert(self.name.deserialize.clone()); + } + + pub fn skip_serializing(&self) -> bool { + self.skip_serializing + } + + pub fn skip_deserializing(&self) -> bool { + self.skip_deserializing + } + + pub fn skip_serializing_if(&self) -> Option<&syn::ExprPath> { + self.skip_serializing_if.as_ref() + } + + pub fn default(&self) -> &Default { + &self.default + } + + pub fn serialize_with(&self) -> Option<&syn::ExprPath> { + self.serialize_with.as_ref() + } + + pub fn deserialize_with(&self) -> Option<&syn::ExprPath> { + self.deserialize_with.as_ref() + } + + pub fn ser_bound(&self) -> Option<&[syn::WherePredicate]> { + self.ser_bound.as_ref().map(|vec| &vec[..]) + } + + pub fn de_bound(&self) -> Option<&[syn::WherePredicate]> { + self.de_bound.as_ref().map(|vec| &vec[..]) + } + + pub fn borrowed_lifetimes(&self) -> &BTreeSet<syn::Lifetime> { + &self.borrowed_lifetimes + } + + pub fn getter(&self) -> Option<&syn::ExprPath> { + self.getter.as_ref() + } + + pub fn flatten(&self) -> bool { + self.flatten + } + + pub fn transparent(&self) -> bool { + self.transparent + } + + pub fn mark_transparent(&mut self) { + self.transparent = true; + } +} + +type SerAndDe<T> = (Option<T>, Option<T>); + +fn get_ser_and_de<'c, T, F, R>( + cx: &'c Ctxt, + attr_name: Symbol, + meta: &ParseNestedMeta, + f: F, +) -> syn::Result<(VecAttr<'c, T>, VecAttr<'c, T>)> +where + T: Clone, + F: Fn(&Ctxt, Symbol, Symbol, &ParseNestedMeta) -> syn::Result<R>, + R: Into<Option<T>>, +{ + let mut ser_meta = VecAttr::none(cx, attr_name); + let mut de_meta = VecAttr::none(cx, attr_name); + + let lookahead = meta.input.lookahead1(); + if lookahead.peek(Token![=]) { + if let Some(both) = f(cx, attr_name, attr_name, meta)?.into() { + ser_meta.insert(&meta.path, both.clone()); + de_meta.insert(&meta.path, both); + } + } else if lookahead.peek(token::Paren) { + meta.parse_nested_meta(|meta| { + if meta.path == SERIALIZE { + if let Some(v) = f(cx, attr_name, SERIALIZE, &meta)?.into() { + ser_meta.insert(&meta.path, v); + } + } else if meta.path == DESERIALIZE { + if let Some(v) = f(cx, attr_name, DESERIALIZE, &meta)?.into() { + de_meta.insert(&meta.path, v); + } + } else { + return Err(meta.error(format_args!( + "malformed {0} attribute, expected `{0}(serialize = ..., deserialize = ...)`", + attr_name, + ))); + } + Ok(()) + })?; + } else { + return Err(lookahead.error()); + } + + Ok((ser_meta, de_meta)) +} + +fn get_renames( + cx: &Ctxt, + attr_name: Symbol, + meta: &ParseNestedMeta, +) -> syn::Result<SerAndDe<syn::LitStr>> { + let (ser, de) = get_ser_and_de(cx, attr_name, meta, get_lit_str2)?; + Ok((ser.at_most_one(), de.at_most_one())) +} + +fn get_multiple_renames( + cx: &Ctxt, + meta: &ParseNestedMeta, +) -> syn::Result<(Option<syn::LitStr>, Vec<syn::LitStr>)> { + let (ser, de) = get_ser_and_de(cx, RENAME, meta, get_lit_str2)?; + Ok((ser.at_most_one(), de.get())) +} + +fn get_where_predicates( + cx: &Ctxt, + meta: &ParseNestedMeta, +) -> syn::Result<SerAndDe<Vec<syn::WherePredicate>>> { + let (ser, de) = get_ser_and_de(cx, BOUND, meta, parse_lit_into_where)?; + Ok((ser.at_most_one(), de.at_most_one())) +} + +fn get_lit_str( + cx: &Ctxt, + attr_name: Symbol, + meta: &ParseNestedMeta, +) -> syn::Result<Option<syn::LitStr>> { + get_lit_str2(cx, attr_name, attr_name, meta) +} + +fn get_lit_str2( + cx: &Ctxt, + attr_name: Symbol, + meta_item_name: Symbol, + meta: &ParseNestedMeta, +) -> syn::Result<Option<syn::LitStr>> { + let expr: syn::Expr = meta.value()?.parse()?; + let mut value = &expr; + while let syn::Expr::Group(e) = value { + value = &e.expr; + } + if let syn::Expr::Lit(syn::ExprLit { + lit: syn::Lit::Str(lit), + .. + }) = value + { + let suffix = lit.suffix(); + if !suffix.is_empty() { + cx.error_spanned_by( + lit, + format!("unexpected suffix `{}` on string literal", suffix), + ); + } + Ok(Some(lit.clone())) + } else { + cx.error_spanned_by( + expr, + format!( + "expected serde {} attribute to be a string: `{} = \"...\"`", + attr_name, meta_item_name + ), + ); + Ok(None) + } +} + +fn parse_lit_into_path( + cx: &Ctxt, + attr_name: Symbol, + meta: &ParseNestedMeta, +) -> syn::Result<Option<syn::Path>> { + let string = match get_lit_str(cx, attr_name, meta)? { + Some(string) => string, + None => return Ok(None), + }; + + Ok(match string.parse() { + Ok(path) => Some(path), + Err(_) => { + cx.error_spanned_by( + &string, + format!("failed to parse path: {:?}", string.value()), + ); + None + } + }) +} + +fn parse_lit_into_expr_path( + cx: &Ctxt, + attr_name: Symbol, + meta: &ParseNestedMeta, +) -> syn::Result<Option<syn::ExprPath>> { + let string = match get_lit_str(cx, attr_name, meta)? { + Some(string) => string, + None => return Ok(None), + }; + + Ok(match string.parse() { + Ok(expr) => Some(expr), + Err(_) => { + cx.error_spanned_by( + &string, + format!("failed to parse path: {:?}", string.value()), + ); + None + } + }) +} + +fn parse_lit_into_where( + cx: &Ctxt, + attr_name: Symbol, + meta_item_name: Symbol, + meta: &ParseNestedMeta, +) -> syn::Result<Vec<syn::WherePredicate>> { + let string = match get_lit_str2(cx, attr_name, meta_item_name, meta)? { + Some(string) => string, + None => return Ok(Vec::new()), + }; + + Ok( + match string.parse_with(Punctuated::<syn::WherePredicate, Token![,]>::parse_terminated) { + Ok(predicates) => Vec::from_iter(predicates), + Err(err) => { + cx.error_spanned_by(string, err); + Vec::new() + } + }, + ) +} + +fn parse_lit_into_ty( + cx: &Ctxt, + attr_name: Symbol, + meta: &ParseNestedMeta, +) -> syn::Result<Option<syn::Type>> { + let string = match get_lit_str(cx, attr_name, meta)? { + Some(string) => string, + None => return Ok(None), + }; + + Ok(match string.parse() { + Ok(ty) => Some(ty), + Err(_) => { + cx.error_spanned_by( + &string, + format!("failed to parse type: {} = {:?}", attr_name, string.value()), + ); + None + } + }) +} + +// Parses a string literal like "'a + 'b + 'c" containing a nonempty list of +// lifetimes separated by `+`. +fn parse_lit_into_lifetimes( + cx: &Ctxt, + meta: &ParseNestedMeta, +) -> syn::Result<BTreeSet<syn::Lifetime>> { + let string = match get_lit_str(cx, BORROW, meta)? { + Some(string) => string, + None => return Ok(BTreeSet::new()), + }; + + if let Ok(lifetimes) = string.parse_with(|input: ParseStream| { + let mut set = BTreeSet::new(); + while !input.is_empty() { + let lifetime: Lifetime = input.parse()?; + if !set.insert(lifetime.clone()) { + cx.error_spanned_by( + &string, + format!("duplicate borrowed lifetime `{}`", lifetime), + ); + } + if input.is_empty() { + break; + } + input.parse::<Token![+]>()?; + } + Ok(set) + }) { + if lifetimes.is_empty() { + cx.error_spanned_by(string, "at least one lifetime must be borrowed"); + } + return Ok(lifetimes); + } + + cx.error_spanned_by( + &string, + format!("failed to parse borrowed lifetimes: {:?}", string.value()), + ); + Ok(BTreeSet::new()) +} + +fn is_implicitly_borrowed(ty: &syn::Type) -> bool { + is_implicitly_borrowed_reference(ty) || is_option(ty, is_implicitly_borrowed_reference) +} + +fn is_implicitly_borrowed_reference(ty: &syn::Type) -> bool { + is_reference(ty, is_str) || is_reference(ty, is_slice_u8) +} + +// Whether the type looks like it might be `std::borrow::Cow<T>` where elem="T". +// This can have false negatives and false positives. +// +// False negative: +// +// use std::borrow::Cow as Pig; +// +// #[derive(Deserialize)] +// struct S<'a> { +// #[serde(borrow)] +// pig: Pig<'a, str>, +// } +// +// False positive: +// +// type str = [i16]; +// +// #[derive(Deserialize)] +// struct S<'a> { +// #[serde(borrow)] +// cow: Cow<'a, str>, +// } +fn is_cow(ty: &syn::Type, elem: fn(&syn::Type) -> bool) -> bool { + let path = match ungroup(ty) { + syn::Type::Path(ty) => &ty.path, + _ => { + return false; + } + }; + let seg = match path.segments.last() { + Some(seg) => seg, + None => { + return false; + } + }; + let args = match &seg.arguments { + syn::PathArguments::AngleBracketed(bracketed) => &bracketed.args, + _ => { + return false; + } + }; + seg.ident == "Cow" + && args.len() == 2 + && match (&args[0], &args[1]) { + (syn::GenericArgument::Lifetime(_), syn::GenericArgument::Type(arg)) => elem(arg), + _ => false, + } +} + +fn is_option(ty: &syn::Type, elem: fn(&syn::Type) -> bool) -> bool { + let path = match ungroup(ty) { + syn::Type::Path(ty) => &ty.path, + _ => { + return false; + } + }; + let seg = match path.segments.last() { + Some(seg) => seg, + None => { + return false; + } + }; + let args = match &seg.arguments { + syn::PathArguments::AngleBracketed(bracketed) => &bracketed.args, + _ => { + return false; + } + }; + seg.ident == "Option" + && args.len() == 1 + && match &args[0] { + syn::GenericArgument::Type(arg) => elem(arg), + _ => false, + } +} + +// Whether the type looks like it might be `&T` where elem="T". This can have +// false negatives and false positives. +// +// False negative: +// +// type Yarn = str; +// +// #[derive(Deserialize)] +// struct S<'a> { +// r: &'a Yarn, +// } +// +// False positive: +// +// type str = [i16]; +// +// #[derive(Deserialize)] +// struct S<'a> { +// r: &'a str, +// } +fn is_reference(ty: &syn::Type, elem: fn(&syn::Type) -> bool) -> bool { + match ungroup(ty) { + syn::Type::Reference(ty) => ty.mutability.is_none() && elem(&ty.elem), + _ => false, + } +} + +fn is_str(ty: &syn::Type) -> bool { + is_primitive_type(ty, "str") +} + +fn is_slice_u8(ty: &syn::Type) -> bool { + match ungroup(ty) { + syn::Type::Slice(ty) => is_primitive_type(&ty.elem, "u8"), + _ => false, + } +} + +fn is_primitive_type(ty: &syn::Type, primitive: &str) -> bool { + match ungroup(ty) { + syn::Type::Path(ty) => ty.qself.is_none() && is_primitive_path(&ty.path, primitive), + _ => false, + } +} + +fn is_primitive_path(path: &syn::Path, primitive: &str) -> bool { + path.leading_colon.is_none() + && path.segments.len() == 1 + && path.segments[0].ident == primitive + && path.segments[0].arguments.is_empty() +} + +// All lifetimes that this type could borrow from a Deserializer. +// +// For example a type `S<'a, 'b>` could borrow `'a` and `'b`. On the other hand +// a type `for<'a> fn(&'a str)` could not borrow `'a` from the Deserializer. +// +// This is used when there is an explicit or implicit `#[serde(borrow)]` +// attribute on the field so there must be at least one borrowable lifetime. +fn borrowable_lifetimes( + cx: &Ctxt, + name: &str, + field: &syn::Field, +) -> Result<BTreeSet<syn::Lifetime>, ()> { + let mut lifetimes = BTreeSet::new(); + collect_lifetimes(&field.ty, &mut lifetimes); + if lifetimes.is_empty() { + let msg = format!("field `{}` has no lifetimes to borrow", name); + cx.error_spanned_by(field, msg); + Err(()) + } else { + Ok(lifetimes) + } +} + +fn collect_lifetimes(ty: &syn::Type, out: &mut BTreeSet<syn::Lifetime>) { + match ty { + #![cfg_attr(all(test, exhaustive), deny(non_exhaustive_omitted_patterns))] + syn::Type::Slice(ty) => { + collect_lifetimes(&ty.elem, out); + } + syn::Type::Array(ty) => { + collect_lifetimes(&ty.elem, out); + } + syn::Type::Ptr(ty) => { + collect_lifetimes(&ty.elem, out); + } + syn::Type::Reference(ty) => { + out.extend(ty.lifetime.iter().cloned()); + collect_lifetimes(&ty.elem, out); + } + syn::Type::Tuple(ty) => { + for elem in &ty.elems { + collect_lifetimes(elem, out); + } + } + syn::Type::Path(ty) => { + if let Some(qself) = &ty.qself { + collect_lifetimes(&qself.ty, out); + } + for seg in &ty.path.segments { + if let syn::PathArguments::AngleBracketed(bracketed) = &seg.arguments { + for arg in &bracketed.args { + match arg { + syn::GenericArgument::Lifetime(lifetime) => { + out.insert(lifetime.clone()); + } + syn::GenericArgument::Type(ty) => { + collect_lifetimes(ty, out); + } + syn::GenericArgument::AssocType(binding) => { + collect_lifetimes(&binding.ty, out); + } + syn::GenericArgument::Const(_) + | syn::GenericArgument::AssocConst(_) + | syn::GenericArgument::Constraint(_) + | _ => {} + } + } + } + } + } + syn::Type::Paren(ty) => { + collect_lifetimes(&ty.elem, out); + } + syn::Type::Group(ty) => { + collect_lifetimes(&ty.elem, out); + } + syn::Type::Macro(ty) => { + collect_lifetimes_from_tokens(ty.mac.tokens.clone(), out); + } + syn::Type::BareFn(_) + | syn::Type::Never(_) + | syn::Type::TraitObject(_) + | syn::Type::ImplTrait(_) + | syn::Type::Infer(_) + | syn::Type::Verbatim(_) => {} + + _ => {} + } +} + +fn collect_lifetimes_from_tokens(tokens: TokenStream, out: &mut BTreeSet<syn::Lifetime>) { + let mut iter = tokens.into_iter(); + while let Some(tt) = iter.next() { + match &tt { + TokenTree::Punct(op) if op.as_char() == '\'' && op.spacing() == Spacing::Joint => { + if let Some(TokenTree::Ident(ident)) = iter.next() { + out.insert(syn::Lifetime { + apostrophe: op.span(), + ident, + }); + } + } + TokenTree::Group(group) => { + let tokens = group.stream(); + collect_lifetimes_from_tokens(tokens, out); + } + _ => {} + } + } +} diff --git a/third_party/rust/serde_derive/src/internals/case.rs b/third_party/rust/serde_derive/src/internals/case.rs new file mode 100644 index 0000000000..8c8c02e757 --- /dev/null +++ b/third_party/rust/serde_derive/src/internals/case.rs @@ -0,0 +1,200 @@ +//! Code to convert the Rust-styled field/variant (e.g. `my_field`, `MyType`) to the +//! case of the source (e.g. `my-field`, `MY_FIELD`). + +use self::RenameRule::*; +use std::fmt::{self, Debug, Display}; + +/// The different possible ways to change case of fields in a struct, or variants in an enum. +#[derive(Copy, Clone, PartialEq)] +pub enum RenameRule { + /// Don't apply a default rename rule. + None, + /// Rename direct children to "lowercase" style. + LowerCase, + /// Rename direct children to "UPPERCASE" style. + UpperCase, + /// Rename direct children to "PascalCase" style, as typically used for + /// enum variants. + PascalCase, + /// Rename direct children to "camelCase" style. + CamelCase, + /// Rename direct children to "snake_case" style, as commonly used for + /// fields. + SnakeCase, + /// Rename direct children to "SCREAMING_SNAKE_CASE" style, as commonly + /// used for constants. + ScreamingSnakeCase, + /// Rename direct children to "kebab-case" style. + KebabCase, + /// Rename direct children to "SCREAMING-KEBAB-CASE" style. + ScreamingKebabCase, +} + +static RENAME_RULES: &[(&str, RenameRule)] = &[ + ("lowercase", LowerCase), + ("UPPERCASE", UpperCase), + ("PascalCase", PascalCase), + ("camelCase", CamelCase), + ("snake_case", SnakeCase), + ("SCREAMING_SNAKE_CASE", ScreamingSnakeCase), + ("kebab-case", KebabCase), + ("SCREAMING-KEBAB-CASE", ScreamingKebabCase), +]; + +impl RenameRule { + pub fn from_str(rename_all_str: &str) -> Result<Self, ParseError> { + for (name, rule) in RENAME_RULES { + if rename_all_str == *name { + return Ok(*rule); + } + } + Err(ParseError { + unknown: rename_all_str, + }) + } + + /// Apply a renaming rule to an enum variant, returning the version expected in the source. + pub fn apply_to_variant(self, variant: &str) -> String { + match self { + None | PascalCase => variant.to_owned(), + LowerCase => variant.to_ascii_lowercase(), + UpperCase => variant.to_ascii_uppercase(), + CamelCase => variant[..1].to_ascii_lowercase() + &variant[1..], + SnakeCase => { + let mut snake = String::new(); + for (i, ch) in variant.char_indices() { + if i > 0 && ch.is_uppercase() { + snake.push('_'); + } + snake.push(ch.to_ascii_lowercase()); + } + snake + } + ScreamingSnakeCase => SnakeCase.apply_to_variant(variant).to_ascii_uppercase(), + KebabCase => SnakeCase.apply_to_variant(variant).replace('_', "-"), + ScreamingKebabCase => ScreamingSnakeCase + .apply_to_variant(variant) + .replace('_', "-"), + } + } + + /// Apply a renaming rule to a struct field, returning the version expected in the source. + pub fn apply_to_field(self, field: &str) -> String { + match self { + None | LowerCase | SnakeCase => field.to_owned(), + UpperCase => field.to_ascii_uppercase(), + PascalCase => { + let mut pascal = String::new(); + let mut capitalize = true; + for ch in field.chars() { + if ch == '_' { + capitalize = true; + } else if capitalize { + pascal.push(ch.to_ascii_uppercase()); + capitalize = false; + } else { + pascal.push(ch); + } + } + pascal + } + CamelCase => { + let pascal = PascalCase.apply_to_field(field); + pascal[..1].to_ascii_lowercase() + &pascal[1..] + } + ScreamingSnakeCase => field.to_ascii_uppercase(), + KebabCase => field.replace('_', "-"), + ScreamingKebabCase => ScreamingSnakeCase.apply_to_field(field).replace('_', "-"), + } + } + + /// Returns the `RenameRule` if it is not `None`, `rule_b` otherwise. + pub fn or(self, rule_b: Self) -> Self { + match self { + None => rule_b, + _ => self, + } + } +} + +pub struct ParseError<'a> { + unknown: &'a str, +} + +impl<'a> Display for ParseError<'a> { + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + f.write_str("unknown rename rule `rename_all = ")?; + Debug::fmt(self.unknown, f)?; + f.write_str("`, expected one of ")?; + for (i, (name, _rule)) in RENAME_RULES.iter().enumerate() { + if i > 0 { + f.write_str(", ")?; + } + Debug::fmt(name, f)?; + } + Ok(()) + } +} + +#[test] +fn rename_variants() { + for &(original, lower, upper, camel, snake, screaming, kebab, screaming_kebab) in &[ + ( + "Outcome", "outcome", "OUTCOME", "outcome", "outcome", "OUTCOME", "outcome", "OUTCOME", + ), + ( + "VeryTasty", + "verytasty", + "VERYTASTY", + "veryTasty", + "very_tasty", + "VERY_TASTY", + "very-tasty", + "VERY-TASTY", + ), + ("A", "a", "A", "a", "a", "A", "a", "A"), + ("Z42", "z42", "Z42", "z42", "z42", "Z42", "z42", "Z42"), + ] { + assert_eq!(None.apply_to_variant(original), original); + assert_eq!(LowerCase.apply_to_variant(original), lower); + assert_eq!(UpperCase.apply_to_variant(original), upper); + assert_eq!(PascalCase.apply_to_variant(original), original); + assert_eq!(CamelCase.apply_to_variant(original), camel); + assert_eq!(SnakeCase.apply_to_variant(original), snake); + assert_eq!(ScreamingSnakeCase.apply_to_variant(original), screaming); + assert_eq!(KebabCase.apply_to_variant(original), kebab); + assert_eq!( + ScreamingKebabCase.apply_to_variant(original), + screaming_kebab + ); + } +} + +#[test] +fn rename_fields() { + for &(original, upper, pascal, camel, screaming, kebab, screaming_kebab) in &[ + ( + "outcome", "OUTCOME", "Outcome", "outcome", "OUTCOME", "outcome", "OUTCOME", + ), + ( + "very_tasty", + "VERY_TASTY", + "VeryTasty", + "veryTasty", + "VERY_TASTY", + "very-tasty", + "VERY-TASTY", + ), + ("a", "A", "A", "a", "A", "a", "A"), + ("z42", "Z42", "Z42", "z42", "Z42", "z42", "Z42"), + ] { + assert_eq!(None.apply_to_field(original), original); + assert_eq!(UpperCase.apply_to_field(original), upper); + assert_eq!(PascalCase.apply_to_field(original), pascal); + assert_eq!(CamelCase.apply_to_field(original), camel); + assert_eq!(SnakeCase.apply_to_field(original), original); + assert_eq!(ScreamingSnakeCase.apply_to_field(original), screaming); + assert_eq!(KebabCase.apply_to_field(original), kebab); + assert_eq!(ScreamingKebabCase.apply_to_field(original), screaming_kebab); + } +} diff --git a/third_party/rust/serde_derive/src/internals/check.rs b/third_party/rust/serde_derive/src/internals/check.rs new file mode 100644 index 0000000000..52b0f379fd --- /dev/null +++ b/third_party/rust/serde_derive/src/internals/check.rs @@ -0,0 +1,477 @@ +use crate::internals::ast::{Container, Data, Field, Style}; +use crate::internals::attr::{Default, Identifier, TagType}; +use crate::internals::{ungroup, Ctxt, Derive}; +use syn::{Member, Type}; + +// Cross-cutting checks that require looking at more than a single attrs object. +// Simpler checks should happen when parsing and building the attrs. +pub fn check(cx: &Ctxt, cont: &mut Container, derive: Derive) { + check_default_on_tuple(cx, cont); + check_remote_generic(cx, cont); + check_getter(cx, cont); + check_flatten(cx, cont); + check_identifier(cx, cont); + check_variant_skip_attrs(cx, cont); + check_internal_tag_field_name_conflict(cx, cont); + check_adjacent_tag_conflict(cx, cont); + check_transparent(cx, cont, derive); + check_from_and_try_from(cx, cont); +} + +// If some field of a tuple struct is marked #[serde(default)] then all fields +// after it must also be marked with that attribute, or the struct must have a +// container-level serde(default) attribute. A field's default value is only +// used for tuple fields if the sequence is exhausted at that point; that means +// all subsequent fields will fail to deserialize if they don't have their own +// default. +fn check_default_on_tuple(cx: &Ctxt, cont: &Container) { + if let Default::None = cont.attrs.default() { + if let Data::Struct(Style::Tuple, fields) = &cont.data { + let mut first_default_index = None; + for (i, field) in fields.iter().enumerate() { + // Skipped fields automatically get the #[serde(default)] + // attribute. We are interested only on non-skipped fields here. + if field.attrs.skip_deserializing() { + continue; + } + if let Default::None = field.attrs.default() { + if let Some(first) = first_default_index { + cx.error_spanned_by( + field.ty, + format!("field must have #[serde(default)] because previous field {} has #[serde(default)]", first), + ); + } + continue; + } + if first_default_index.is_none() { + first_default_index = Some(i); + } + } + } + } +} + +// Remote derive definition type must have either all of the generics of the +// remote type: +// +// #[serde(remote = "Generic")] +// struct Generic<T> {…} +// +// or none of them, i.e. defining impls for one concrete instantiation of the +// remote type only: +// +// #[serde(remote = "Generic<T>")] +// struct ConcreteDef {…} +// +fn check_remote_generic(cx: &Ctxt, cont: &Container) { + if let Some(remote) = cont.attrs.remote() { + let local_has_generic = !cont.generics.params.is_empty(); + let remote_has_generic = !remote.segments.last().unwrap().arguments.is_none(); + if local_has_generic && remote_has_generic { + cx.error_spanned_by(remote, "remove generic parameters from this path"); + } + } +} + +// Getters are only allowed inside structs (not enums) with the `remote` +// attribute. +fn check_getter(cx: &Ctxt, cont: &Container) { + match cont.data { + Data::Enum(_) => { + if cont.data.has_getter() { + cx.error_spanned_by( + cont.original, + "#[serde(getter = \"...\")] is not allowed in an enum", + ); + } + } + Data::Struct(_, _) => { + if cont.data.has_getter() && cont.attrs.remote().is_none() { + cx.error_spanned_by( + cont.original, + "#[serde(getter = \"...\")] can only be used in structs that have #[serde(remote = \"...\")]", + ); + } + } + } +} + +// Flattening has some restrictions we can test. +fn check_flatten(cx: &Ctxt, cont: &Container) { + match &cont.data { + Data::Enum(variants) => { + for variant in variants { + for field in &variant.fields { + check_flatten_field(cx, variant.style, field); + } + } + } + Data::Struct(style, fields) => { + for field in fields { + check_flatten_field(cx, *style, field); + } + } + } +} + +fn check_flatten_field(cx: &Ctxt, style: Style, field: &Field) { + if !field.attrs.flatten() { + return; + } + match style { + Style::Tuple => { + cx.error_spanned_by( + field.original, + "#[serde(flatten)] cannot be used on tuple structs", + ); + } + Style::Newtype => { + cx.error_spanned_by( + field.original, + "#[serde(flatten)] cannot be used on newtype structs", + ); + } + _ => {} + } +} + +// The `other` attribute must be used at most once and it must be the last +// variant of an enum. +// +// Inside a `variant_identifier` all variants must be unit variants. Inside a +// `field_identifier` all but possibly one variant must be unit variants. The +// last variant may be a newtype variant which is an implicit "other" case. +fn check_identifier(cx: &Ctxt, cont: &Container) { + let variants = match &cont.data { + Data::Enum(variants) => variants, + Data::Struct(_, _) => return, + }; + + for (i, variant) in variants.iter().enumerate() { + match ( + variant.style, + cont.attrs.identifier(), + variant.attrs.other(), + cont.attrs.tag(), + ) { + // The `other` attribute may not be used in a variant_identifier. + (_, Identifier::Variant, true, _) => { + cx.error_spanned_by( + variant.original, + "#[serde(other)] may not be used on a variant identifier", + ); + } + + // Variant with `other` attribute cannot appear in untagged enum + (_, Identifier::No, true, &TagType::None) => { + cx.error_spanned_by( + variant.original, + "#[serde(other)] cannot appear on untagged enum", + ); + } + + // Variant with `other` attribute must be the last one. + (Style::Unit, Identifier::Field, true, _) | (Style::Unit, Identifier::No, true, _) => { + if i < variants.len() - 1 { + cx.error_spanned_by( + variant.original, + "#[serde(other)] must be on the last variant", + ); + } + } + + // Variant with `other` attribute must be a unit variant. + (_, Identifier::Field, true, _) | (_, Identifier::No, true, _) => { + cx.error_spanned_by( + variant.original, + "#[serde(other)] must be on a unit variant", + ); + } + + // Any sort of variant is allowed if this is not an identifier. + (_, Identifier::No, false, _) => {} + + // Unit variant without `other` attribute is always fine. + (Style::Unit, _, false, _) => {} + + // The last field is allowed to be a newtype catch-all. + (Style::Newtype, Identifier::Field, false, _) => { + if i < variants.len() - 1 { + cx.error_spanned_by( + variant.original, + format!("`{}` must be the last variant", variant.ident), + ); + } + } + + (_, Identifier::Field, false, _) => { + cx.error_spanned_by( + variant.original, + "#[serde(field_identifier)] may only contain unit variants", + ); + } + + (_, Identifier::Variant, false, _) => { + cx.error_spanned_by( + variant.original, + "#[serde(variant_identifier)] may only contain unit variants", + ); + } + } + } +} + +// Skip-(de)serializing attributes are not allowed on variants marked +// (de)serialize_with. +fn check_variant_skip_attrs(cx: &Ctxt, cont: &Container) { + let variants = match &cont.data { + Data::Enum(variants) => variants, + Data::Struct(_, _) => return, + }; + + for variant in variants { + if variant.attrs.serialize_with().is_some() { + if variant.attrs.skip_serializing() { + cx.error_spanned_by( + variant.original, + format!( + "variant `{}` cannot have both #[serde(serialize_with)] and #[serde(skip_serializing)]", + variant.ident + ), + ); + } + + for field in &variant.fields { + let member = member_message(&field.member); + + if field.attrs.skip_serializing() { + cx.error_spanned_by( + variant.original, + format!( + "variant `{}` cannot have both #[serde(serialize_with)] and a field {} marked with #[serde(skip_serializing)]", + variant.ident, member + ), + ); + } + + if field.attrs.skip_serializing_if().is_some() { + cx.error_spanned_by( + variant.original, + format!( + "variant `{}` cannot have both #[serde(serialize_with)] and a field {} marked with #[serde(skip_serializing_if)]", + variant.ident, member + ), + ); + } + } + } + + if variant.attrs.deserialize_with().is_some() { + if variant.attrs.skip_deserializing() { + cx.error_spanned_by( + variant.original, + format!( + "variant `{}` cannot have both #[serde(deserialize_with)] and #[serde(skip_deserializing)]", + variant.ident + ), + ); + } + + for field in &variant.fields { + if field.attrs.skip_deserializing() { + let member = member_message(&field.member); + + cx.error_spanned_by( + variant.original, + format!( + "variant `{}` cannot have both #[serde(deserialize_with)] and a field {} marked with #[serde(skip_deserializing)]", + variant.ident, member + ), + ); + } + } + } + } +} + +// The tag of an internally-tagged struct variant must not be the same as either +// one of its fields, as this would result in duplicate keys in the serialized +// output and/or ambiguity in the to-be-deserialized input. +fn check_internal_tag_field_name_conflict(cx: &Ctxt, cont: &Container) { + let variants = match &cont.data { + Data::Enum(variants) => variants, + Data::Struct(_, _) => return, + }; + + let tag = match cont.attrs.tag() { + TagType::Internal { tag } => tag.as_str(), + TagType::External | TagType::Adjacent { .. } | TagType::None => return, + }; + + let diagnose_conflict = || { + cx.error_spanned_by( + cont.original, + format!("variant field name `{}` conflicts with internal tag", tag), + ); + }; + + for variant in variants { + match variant.style { + Style::Struct => { + if variant.attrs.untagged() { + continue; + } + for field in &variant.fields { + let check_ser = + !(field.attrs.skip_serializing() || variant.attrs.skip_serializing()); + let check_de = + !(field.attrs.skip_deserializing() || variant.attrs.skip_deserializing()); + let name = field.attrs.name(); + let ser_name = name.serialize_name(); + + if check_ser && ser_name == tag { + diagnose_conflict(); + return; + } + + for de_name in field.attrs.aliases() { + if check_de && de_name == tag { + diagnose_conflict(); + return; + } + } + } + } + Style::Unit | Style::Newtype | Style::Tuple => {} + } + } +} + +// In the case of adjacently-tagged enums, the type and the contents tag must +// differ, for the same reason. +fn check_adjacent_tag_conflict(cx: &Ctxt, cont: &Container) { + let (type_tag, content_tag) = match cont.attrs.tag() { + TagType::Adjacent { tag, content } => (tag, content), + TagType::Internal { .. } | TagType::External | TagType::None => return, + }; + + if type_tag == content_tag { + cx.error_spanned_by( + cont.original, + format!( + "enum tags `{}` for type and content conflict with each other", + type_tag + ), + ); + } +} + +// Enums and unit structs cannot be transparent. +fn check_transparent(cx: &Ctxt, cont: &mut Container, derive: Derive) { + if !cont.attrs.transparent() { + return; + } + + if cont.attrs.type_from().is_some() { + cx.error_spanned_by( + cont.original, + "#[serde(transparent)] is not allowed with #[serde(from = \"...\")]", + ); + } + + if cont.attrs.type_try_from().is_some() { + cx.error_spanned_by( + cont.original, + "#[serde(transparent)] is not allowed with #[serde(try_from = \"...\")]", + ); + } + + if cont.attrs.type_into().is_some() { + cx.error_spanned_by( + cont.original, + "#[serde(transparent)] is not allowed with #[serde(into = \"...\")]", + ); + } + + let fields = match &mut cont.data { + Data::Enum(_) => { + cx.error_spanned_by( + cont.original, + "#[serde(transparent)] is not allowed on an enum", + ); + return; + } + Data::Struct(Style::Unit, _) => { + cx.error_spanned_by( + cont.original, + "#[serde(transparent)] is not allowed on a unit struct", + ); + return; + } + Data::Struct(_, fields) => fields, + }; + + let mut transparent_field = None; + + for field in fields { + if allow_transparent(field, derive) { + if transparent_field.is_some() { + cx.error_spanned_by( + cont.original, + "#[serde(transparent)] requires struct to have at most one transparent field", + ); + return; + } + transparent_field = Some(field); + } + } + + match transparent_field { + Some(transparent_field) => transparent_field.attrs.mark_transparent(), + None => match derive { + Derive::Serialize => { + cx.error_spanned_by( + cont.original, + "#[serde(transparent)] requires at least one field that is not skipped", + ); + } + Derive::Deserialize => { + cx.error_spanned_by( + cont.original, + "#[serde(transparent)] requires at least one field that is neither skipped nor has a default", + ); + } + }, + } +} + +fn member_message(member: &Member) -> String { + match member { + Member::Named(ident) => format!("`{}`", ident), + Member::Unnamed(i) => format!("#{}", i.index), + } +} + +fn allow_transparent(field: &Field, derive: Derive) -> bool { + if let Type::Path(ty) = ungroup(field.ty) { + if let Some(seg) = ty.path.segments.last() { + if seg.ident == "PhantomData" { + return false; + } + } + } + + match derive { + Derive::Serialize => !field.attrs.skip_serializing(), + Derive::Deserialize => !field.attrs.skip_deserializing() && field.attrs.default().is_none(), + } +} + +fn check_from_and_try_from(cx: &Ctxt, cont: &mut Container) { + if cont.attrs.type_from().is_some() && cont.attrs.type_try_from().is_some() { + cx.error_spanned_by( + cont.original, + "#[serde(from = \"...\")] and #[serde(try_from = \"...\")] conflict with each other", + ); + } +} diff --git a/third_party/rust/serde_derive/src/internals/ctxt.rs b/third_party/rust/serde_derive/src/internals/ctxt.rs new file mode 100644 index 0000000000..a47bfa4102 --- /dev/null +++ b/third_party/rust/serde_derive/src/internals/ctxt.rs @@ -0,0 +1,68 @@ +use quote::ToTokens; +use std::cell::RefCell; +use std::fmt::Display; +use std::thread; + +/// A type to collect errors together and format them. +/// +/// Dropping this object will cause a panic. It must be consumed using `check`. +/// +/// References can be shared since this type uses run-time exclusive mut checking. +#[derive(Default)] +pub struct Ctxt { + // The contents will be set to `None` during checking. This is so that checking can be + // enforced. + errors: RefCell<Option<Vec<syn::Error>>>, +} + +impl Ctxt { + /// Create a new context object. + /// + /// This object contains no errors, but will still trigger a panic if it is not `check`ed. + pub fn new() -> Self { + Ctxt { + errors: RefCell::new(Some(Vec::new())), + } + } + + /// Add an error to the context object with a tokenenizable object. + /// + /// The object is used for spanning in error messages. + pub fn error_spanned_by<A: ToTokens, T: Display>(&self, obj: A, msg: T) { + self.errors + .borrow_mut() + .as_mut() + .unwrap() + // Curb monomorphization from generating too many identical methods. + .push(syn::Error::new_spanned(obj.into_token_stream(), msg)); + } + + /// Add one of Syn's parse errors. + pub fn syn_error(&self, err: syn::Error) { + self.errors.borrow_mut().as_mut().unwrap().push(err); + } + + /// Consume this object, producing a formatted error string if there are errors. + pub fn check(self) -> syn::Result<()> { + let mut errors = self.errors.borrow_mut().take().unwrap().into_iter(); + + let mut combined = match errors.next() { + Some(first) => first, + None => return Ok(()), + }; + + for rest in errors { + combined.combine(rest); + } + + Err(combined) + } +} + +impl Drop for Ctxt { + fn drop(&mut self) { + if !thread::panicking() && self.errors.borrow().is_some() { + panic!("forgot to check for errors"); + } + } +} diff --git a/third_party/rust/serde_derive/src/internals/mod.rs b/third_party/rust/serde_derive/src/internals/mod.rs new file mode 100644 index 0000000000..f98ef08e8c --- /dev/null +++ b/third_party/rust/serde_derive/src/internals/mod.rs @@ -0,0 +1,27 @@ +pub mod ast; +pub mod attr; + +mod case; +mod check; +mod ctxt; +mod receiver; +mod respan; +mod symbol; + +use syn::Type; + +pub use self::ctxt::Ctxt; +pub use self::receiver::replace_receiver; + +#[derive(Copy, Clone)] +pub enum Derive { + Serialize, + Deserialize, +} + +pub fn ungroup(mut ty: &Type) -> &Type { + while let Type::Group(group) = ty { + ty = &group.elem; + } + ty +} diff --git a/third_party/rust/serde_derive/src/internals/receiver.rs b/third_party/rust/serde_derive/src/internals/receiver.rs new file mode 100644 index 0000000000..fa2a77d240 --- /dev/null +++ b/third_party/rust/serde_derive/src/internals/receiver.rs @@ -0,0 +1,292 @@ +use crate::internals::respan::respan; +use proc_macro2::Span; +use quote::ToTokens; +use std::mem; +use syn::punctuated::Punctuated; +use syn::{ + parse_quote, Data, DeriveInput, Expr, ExprPath, GenericArgument, GenericParam, Generics, Macro, + Path, PathArguments, QSelf, ReturnType, Token, Type, TypeParamBound, TypePath, WherePredicate, +}; + +pub fn replace_receiver(input: &mut DeriveInput) { + let self_ty = { + let ident = &input.ident; + let ty_generics = input.generics.split_for_impl().1; + parse_quote!(#ident #ty_generics) + }; + let mut visitor = ReplaceReceiver(&self_ty); + visitor.visit_generics_mut(&mut input.generics); + visitor.visit_data_mut(&mut input.data); +} + +struct ReplaceReceiver<'a>(&'a TypePath); + +impl ReplaceReceiver<'_> { + fn self_ty(&self, span: Span) -> TypePath { + let tokens = self.0.to_token_stream(); + let respanned = respan(tokens, span); + syn::parse2(respanned).unwrap() + } + + fn self_to_qself(&self, qself: &mut Option<QSelf>, path: &mut Path) { + if path.leading_colon.is_some() || path.segments[0].ident != "Self" { + return; + } + + if path.segments.len() == 1 { + self.self_to_expr_path(path); + return; + } + + let span = path.segments[0].ident.span(); + *qself = Some(QSelf { + lt_token: Token, + ty: Box::new(Type::Path(self.self_ty(span))), + position: 0, + as_token: None, + gt_token: Token, + }); + + path.leading_colon = Some(**path.segments.pairs().next().unwrap().punct().unwrap()); + + let segments = mem::replace(&mut path.segments, Punctuated::new()); + path.segments = segments.into_pairs().skip(1).collect(); + } + + fn self_to_expr_path(&self, path: &mut Path) { + let self_ty = self.self_ty(path.segments[0].ident.span()); + let variant = mem::replace(path, self_ty.path); + for segment in &mut path.segments { + if let PathArguments::AngleBracketed(bracketed) = &mut segment.arguments { + if bracketed.colon2_token.is_none() && !bracketed.args.is_empty() { + bracketed.colon2_token = Some(<Token![::]>::default()); + } + } + } + if variant.segments.len() > 1 { + path.segments.push_punct(<Token![::]>::default()); + path.segments.extend(variant.segments.into_pairs().skip(1)); + } + } +} + +impl ReplaceReceiver<'_> { + // `Self` -> `Receiver` + fn visit_type_mut(&mut self, ty: &mut Type) { + let span = if let Type::Path(node) = ty { + if node.qself.is_none() && node.path.is_ident("Self") { + node.path.segments[0].ident.span() + } else { + self.visit_type_path_mut(node); + return; + } + } else { + self.visit_type_mut_impl(ty); + return; + }; + *ty = self.self_ty(span).into(); + } + + // `Self::Assoc` -> `<Receiver>::Assoc` + fn visit_type_path_mut(&mut self, ty: &mut TypePath) { + if ty.qself.is_none() { + self.self_to_qself(&mut ty.qself, &mut ty.path); + } + self.visit_type_path_mut_impl(ty); + } + + // `Self::method` -> `<Receiver>::method` + fn visit_expr_path_mut(&mut self, expr: &mut ExprPath) { + if expr.qself.is_none() { + self.self_to_qself(&mut expr.qself, &mut expr.path); + } + self.visit_expr_path_mut_impl(expr); + } + + // Everything below is simply traversing the syntax tree. + + fn visit_type_mut_impl(&mut self, ty: &mut Type) { + match ty { + #![cfg_attr(all(test, exhaustive), deny(non_exhaustive_omitted_patterns))] + Type::Array(ty) => { + self.visit_type_mut(&mut ty.elem); + self.visit_expr_mut(&mut ty.len); + } + Type::BareFn(ty) => { + for arg in &mut ty.inputs { + self.visit_type_mut(&mut arg.ty); + } + self.visit_return_type_mut(&mut ty.output); + } + Type::Group(ty) => self.visit_type_mut(&mut ty.elem), + Type::ImplTrait(ty) => { + for bound in &mut ty.bounds { + self.visit_type_param_bound_mut(bound); + } + } + Type::Macro(ty) => self.visit_macro_mut(&mut ty.mac), + Type::Paren(ty) => self.visit_type_mut(&mut ty.elem), + Type::Path(ty) => { + if let Some(qself) = &mut ty.qself { + self.visit_type_mut(&mut qself.ty); + } + self.visit_path_mut(&mut ty.path); + } + Type::Ptr(ty) => self.visit_type_mut(&mut ty.elem), + Type::Reference(ty) => self.visit_type_mut(&mut ty.elem), + Type::Slice(ty) => self.visit_type_mut(&mut ty.elem), + Type::TraitObject(ty) => { + for bound in &mut ty.bounds { + self.visit_type_param_bound_mut(bound); + } + } + Type::Tuple(ty) => { + for elem in &mut ty.elems { + self.visit_type_mut(elem); + } + } + + Type::Infer(_) | Type::Never(_) | Type::Verbatim(_) => {} + + _ => {} + } + } + + fn visit_type_path_mut_impl(&mut self, ty: &mut TypePath) { + if let Some(qself) = &mut ty.qself { + self.visit_type_mut(&mut qself.ty); + } + self.visit_path_mut(&mut ty.path); + } + + fn visit_expr_path_mut_impl(&mut self, expr: &mut ExprPath) { + if let Some(qself) = &mut expr.qself { + self.visit_type_mut(&mut qself.ty); + } + self.visit_path_mut(&mut expr.path); + } + + fn visit_path_mut(&mut self, path: &mut Path) { + for segment in &mut path.segments { + self.visit_path_arguments_mut(&mut segment.arguments); + } + } + + fn visit_path_arguments_mut(&mut self, arguments: &mut PathArguments) { + match arguments { + PathArguments::None => {} + PathArguments::AngleBracketed(arguments) => { + for arg in &mut arguments.args { + match arg { + #![cfg_attr(all(test, exhaustive), deny(non_exhaustive_omitted_patterns))] + GenericArgument::Type(arg) => self.visit_type_mut(arg), + GenericArgument::AssocType(arg) => self.visit_type_mut(&mut arg.ty), + GenericArgument::Lifetime(_) + | GenericArgument::Const(_) + | GenericArgument::AssocConst(_) + | GenericArgument::Constraint(_) => {} + _ => {} + } + } + } + PathArguments::Parenthesized(arguments) => { + for argument in &mut arguments.inputs { + self.visit_type_mut(argument); + } + self.visit_return_type_mut(&mut arguments.output); + } + } + } + + fn visit_return_type_mut(&mut self, return_type: &mut ReturnType) { + match return_type { + ReturnType::Default => {} + ReturnType::Type(_, output) => self.visit_type_mut(output), + } + } + + fn visit_type_param_bound_mut(&mut self, bound: &mut TypeParamBound) { + match bound { + #![cfg_attr(all(test, exhaustive), deny(non_exhaustive_omitted_patterns))] + TypeParamBound::Trait(bound) => self.visit_path_mut(&mut bound.path), + TypeParamBound::Lifetime(_) | TypeParamBound::Verbatim(_) => {} + _ => {} + } + } + + fn visit_generics_mut(&mut self, generics: &mut Generics) { + for param in &mut generics.params { + match param { + GenericParam::Type(param) => { + for bound in &mut param.bounds { + self.visit_type_param_bound_mut(bound); + } + } + GenericParam::Lifetime(_) | GenericParam::Const(_) => {} + } + } + if let Some(where_clause) = &mut generics.where_clause { + for predicate in &mut where_clause.predicates { + match predicate { + #![cfg_attr(all(test, exhaustive), deny(non_exhaustive_omitted_patterns))] + WherePredicate::Type(predicate) => { + self.visit_type_mut(&mut predicate.bounded_ty); + for bound in &mut predicate.bounds { + self.visit_type_param_bound_mut(bound); + } + } + WherePredicate::Lifetime(_) => {} + _ => {} + } + } + } + } + + fn visit_data_mut(&mut self, data: &mut Data) { + match data { + Data::Struct(data) => { + for field in &mut data.fields { + self.visit_type_mut(&mut field.ty); + } + } + Data::Enum(data) => { + for variant in &mut data.variants { + for field in &mut variant.fields { + self.visit_type_mut(&mut field.ty); + } + } + } + Data::Union(_) => {} + } + } + + fn visit_expr_mut(&mut self, expr: &mut Expr) { + match expr { + Expr::Binary(expr) => { + self.visit_expr_mut(&mut expr.left); + self.visit_expr_mut(&mut expr.right); + } + Expr::Call(expr) => { + self.visit_expr_mut(&mut expr.func); + for arg in &mut expr.args { + self.visit_expr_mut(arg); + } + } + Expr::Cast(expr) => { + self.visit_expr_mut(&mut expr.expr); + self.visit_type_mut(&mut expr.ty); + } + Expr::Field(expr) => self.visit_expr_mut(&mut expr.base), + Expr::Index(expr) => { + self.visit_expr_mut(&mut expr.expr); + self.visit_expr_mut(&mut expr.index); + } + Expr::Paren(expr) => self.visit_expr_mut(&mut expr.expr), + Expr::Path(expr) => self.visit_expr_path_mut(expr), + Expr::Unary(expr) => self.visit_expr_mut(&mut expr.expr), + _ => {} + } + } + + fn visit_macro_mut(&mut self, _mac: &mut Macro) {} +} diff --git a/third_party/rust/serde_derive/src/internals/respan.rs b/third_party/rust/serde_derive/src/internals/respan.rs new file mode 100644 index 0000000000..dcec7017b3 --- /dev/null +++ b/third_party/rust/serde_derive/src/internals/respan.rs @@ -0,0 +1,16 @@ +use proc_macro2::{Group, Span, TokenStream, TokenTree}; + +pub(crate) fn respan(stream: TokenStream, span: Span) -> TokenStream { + stream + .into_iter() + .map(|token| respan_token(token, span)) + .collect() +} + +fn respan_token(mut token: TokenTree, span: Span) -> TokenTree { + if let TokenTree::Group(g) = &mut token { + *g = Group::new(g.delimiter(), respan(g.stream(), span)); + } + token.set_span(span); + token +} diff --git a/third_party/rust/serde_derive/src/internals/symbol.rs b/third_party/rust/serde_derive/src/internals/symbol.rs new file mode 100644 index 0000000000..572391a807 --- /dev/null +++ b/third_party/rust/serde_derive/src/internals/symbol.rs @@ -0,0 +1,71 @@ +use std::fmt::{self, Display}; +use syn::{Ident, Path}; + +#[derive(Copy, Clone)] +pub struct Symbol(&'static str); + +pub const ALIAS: Symbol = Symbol("alias"); +pub const BORROW: Symbol = Symbol("borrow"); +pub const BOUND: Symbol = Symbol("bound"); +pub const CONTENT: Symbol = Symbol("content"); +pub const CRATE: Symbol = Symbol("crate"); +pub const DEFAULT: Symbol = Symbol("default"); +pub const DENY_UNKNOWN_FIELDS: Symbol = Symbol("deny_unknown_fields"); +pub const DESERIALIZE: Symbol = Symbol("deserialize"); +pub const DESERIALIZE_WITH: Symbol = Symbol("deserialize_with"); +pub const EXPECTING: Symbol = Symbol("expecting"); +pub const FIELD_IDENTIFIER: Symbol = Symbol("field_identifier"); +pub const FLATTEN: Symbol = Symbol("flatten"); +pub const FROM: Symbol = Symbol("from"); +pub const GETTER: Symbol = Symbol("getter"); +pub const INTO: Symbol = Symbol("into"); +pub const NON_EXHAUSTIVE: Symbol = Symbol("non_exhaustive"); +pub const OTHER: Symbol = Symbol("other"); +pub const REMOTE: Symbol = Symbol("remote"); +pub const RENAME: Symbol = Symbol("rename"); +pub const RENAME_ALL: Symbol = Symbol("rename_all"); +pub const RENAME_ALL_FIELDS: Symbol = Symbol("rename_all_fields"); +pub const REPR: Symbol = Symbol("repr"); +pub const SERDE: Symbol = Symbol("serde"); +pub const SERIALIZE: Symbol = Symbol("serialize"); +pub const SERIALIZE_WITH: Symbol = Symbol("serialize_with"); +pub const SKIP: Symbol = Symbol("skip"); +pub const SKIP_DESERIALIZING: Symbol = Symbol("skip_deserializing"); +pub const SKIP_SERIALIZING: Symbol = Symbol("skip_serializing"); +pub const SKIP_SERIALIZING_IF: Symbol = Symbol("skip_serializing_if"); +pub const TAG: Symbol = Symbol("tag"); +pub const TRANSPARENT: Symbol = Symbol("transparent"); +pub const TRY_FROM: Symbol = Symbol("try_from"); +pub const UNTAGGED: Symbol = Symbol("untagged"); +pub const VARIANT_IDENTIFIER: Symbol = Symbol("variant_identifier"); +pub const WITH: Symbol = Symbol("with"); + +impl PartialEq<Symbol> for Ident { + fn eq(&self, word: &Symbol) -> bool { + self == word.0 + } +} + +impl<'a> PartialEq<Symbol> for &'a Ident { + fn eq(&self, word: &Symbol) -> bool { + *self == word.0 + } +} + +impl PartialEq<Symbol> for Path { + fn eq(&self, word: &Symbol) -> bool { + self.is_ident(word.0) + } +} + +impl<'a> PartialEq<Symbol> for &'a Path { + fn eq(&self, word: &Symbol) -> bool { + self.is_ident(word.0) + } +} + +impl Display for Symbol { + fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str(self.0) + } +} |