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-rw-r--r--vendor/thiserror-impl/src/expand.rs562
1 files changed, 0 insertions, 562 deletions
diff --git a/vendor/thiserror-impl/src/expand.rs b/vendor/thiserror-impl/src/expand.rs
deleted file mode 100644
index 1b44513..0000000
--- a/vendor/thiserror-impl/src/expand.rs
+++ /dev/null
@@ -1,562 +0,0 @@
-use crate::ast::{Enum, Field, Input, Struct};
-use crate::attr::Trait;
-use crate::generics::InferredBounds;
-use crate::span::MemberSpan;
-use proc_macro2::TokenStream;
-use quote::{format_ident, quote, quote_spanned, ToTokens};
-use std::collections::BTreeSet as Set;
-use syn::{DeriveInput, GenericArgument, Member, PathArguments, Result, Token, Type};
-
-pub fn derive(input: &DeriveInput) -> TokenStream {
- match try_expand(input) {
- Ok(expanded) => expanded,
- // If there are invalid attributes in the input, expand to an Error impl
- // anyway to minimize spurious knock-on errors in other code that uses
- // this type as an Error.
- Err(error) => fallback(input, error),
- }
-}
-
-fn try_expand(input: &DeriveInput) -> Result<TokenStream> {
- let input = Input::from_syn(input)?;
- input.validate()?;
- Ok(match input {
- Input::Struct(input) => impl_struct(input),
- Input::Enum(input) => impl_enum(input),
- })
-}
-
-fn fallback(input: &DeriveInput, error: syn::Error) -> TokenStream {
- let ty = &input.ident;
- let (impl_generics, ty_generics, where_clause) = input.generics.split_for_impl();
-
- let error = error.to_compile_error();
-
- quote! {
- #error
-
- #[allow(unused_qualifications)]
- impl #impl_generics std::error::Error for #ty #ty_generics #where_clause
- where
- // Work around trivial bounds being unstable.
- // https://github.com/rust-lang/rust/issues/48214
- for<'workaround> #ty #ty_generics: ::core::fmt::Debug,
- {}
-
- #[allow(unused_qualifications)]
- impl #impl_generics ::core::fmt::Display for #ty #ty_generics #where_clause {
- fn fmt(&self, __formatter: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
- ::core::unreachable!()
- }
- }
- }
-}
-
-fn impl_struct(input: Struct) -> TokenStream {
- let ty = &input.ident;
- let (impl_generics, ty_generics, where_clause) = input.generics.split_for_impl();
- let mut error_inferred_bounds = InferredBounds::new();
-
- let source_body = if let Some(transparent_attr) = &input.attrs.transparent {
- let only_field = &input.fields[0];
- if only_field.contains_generic {
- error_inferred_bounds.insert(only_field.ty, quote!(std::error::Error));
- }
- let member = &only_field.member;
- Some(quote_spanned! {transparent_attr.span=>
- std::error::Error::source(self.#member.as_dyn_error())
- })
- } else if let Some(source_field) = input.source_field() {
- let source = &source_field.member;
- if source_field.contains_generic {
- let ty = unoptional_type(source_field.ty);
- error_inferred_bounds.insert(ty, quote!(std::error::Error + 'static));
- }
- let asref = if type_is_option(source_field.ty) {
- Some(quote_spanned!(source.member_span()=> .as_ref()?))
- } else {
- None
- };
- let dyn_error = quote_spanned! {source_field.source_span()=>
- self.#source #asref.as_dyn_error()
- };
- Some(quote! {
- ::core::option::Option::Some(#dyn_error)
- })
- } else {
- None
- };
- let source_method = source_body.map(|body| {
- quote! {
- fn source(&self) -> ::core::option::Option<&(dyn std::error::Error + 'static)> {
- use thiserror::__private::AsDynError as _;
- #body
- }
- }
- });
-
- let provide_method = input.backtrace_field().map(|backtrace_field| {
- let request = quote!(request);
- let backtrace = &backtrace_field.member;
- let body = if let Some(source_field) = input.source_field() {
- let source = &source_field.member;
- let source_provide = if type_is_option(source_field.ty) {
- quote_spanned! {source.member_span()=>
- if let ::core::option::Option::Some(source) = &self.#source {
- source.thiserror_provide(#request);
- }
- }
- } else {
- quote_spanned! {source.member_span()=>
- self.#source.thiserror_provide(#request);
- }
- };
- let self_provide = if source == backtrace {
- None
- } else if type_is_option(backtrace_field.ty) {
- Some(quote! {
- if let ::core::option::Option::Some(backtrace) = &self.#backtrace {
- #request.provide_ref::<std::backtrace::Backtrace>(backtrace);
- }
- })
- } else {
- Some(quote! {
- #request.provide_ref::<std::backtrace::Backtrace>(&self.#backtrace);
- })
- };
- quote! {
- use thiserror::__private::ThiserrorProvide as _;
- #source_provide
- #self_provide
- }
- } else if type_is_option(backtrace_field.ty) {
- quote! {
- if let ::core::option::Option::Some(backtrace) = &self.#backtrace {
- #request.provide_ref::<std::backtrace::Backtrace>(backtrace);
- }
- }
- } else {
- quote! {
- #request.provide_ref::<std::backtrace::Backtrace>(&self.#backtrace);
- }
- };
- quote! {
- fn provide<'_request>(&'_request self, #request: &mut std::error::Request<'_request>) {
- #body
- }
- }
- });
-
- let mut display_implied_bounds = Set::new();
- let display_body = if input.attrs.transparent.is_some() {
- let only_field = &input.fields[0].member;
- display_implied_bounds.insert((0, Trait::Display));
- Some(quote! {
- ::core::fmt::Display::fmt(&self.#only_field, __formatter)
- })
- } else if let Some(display) = &input.attrs.display {
- display_implied_bounds = display.implied_bounds.clone();
- let use_as_display = use_as_display(display.has_bonus_display);
- let pat = fields_pat(&input.fields);
- Some(quote! {
- #use_as_display
- #[allow(unused_variables, deprecated)]
- let Self #pat = self;
- #display
- })
- } else {
- None
- };
- let display_impl = display_body.map(|body| {
- let mut display_inferred_bounds = InferredBounds::new();
- for (field, bound) in display_implied_bounds {
- let field = &input.fields[field];
- if field.contains_generic {
- display_inferred_bounds.insert(field.ty, bound);
- }
- }
- let display_where_clause = display_inferred_bounds.augment_where_clause(input.generics);
- quote! {
- #[allow(unused_qualifications)]
- impl #impl_generics ::core::fmt::Display for #ty #ty_generics #display_where_clause {
- #[allow(clippy::used_underscore_binding)]
- fn fmt(&self, __formatter: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
- #body
- }
- }
- }
- });
-
- let from_impl = input.from_field().map(|from_field| {
- let backtrace_field = input.distinct_backtrace_field();
- let from = unoptional_type(from_field.ty);
- let body = from_initializer(from_field, backtrace_field);
- quote! {
- #[allow(unused_qualifications)]
- impl #impl_generics ::core::convert::From<#from> for #ty #ty_generics #where_clause {
- #[allow(deprecated)]
- fn from(source: #from) -> Self {
- #ty #body
- }
- }
- }
- });
-
- if input.generics.type_params().next().is_some() {
- let self_token = <Token![Self]>::default();
- error_inferred_bounds.insert(self_token, Trait::Debug);
- error_inferred_bounds.insert(self_token, Trait::Display);
- }
- let error_where_clause = error_inferred_bounds.augment_where_clause(input.generics);
-
- quote! {
- #[allow(unused_qualifications)]
- impl #impl_generics std::error::Error for #ty #ty_generics #error_where_clause {
- #source_method
- #provide_method
- }
- #display_impl
- #from_impl
- }
-}
-
-fn impl_enum(input: Enum) -> TokenStream {
- let ty = &input.ident;
- let (impl_generics, ty_generics, where_clause) = input.generics.split_for_impl();
- let mut error_inferred_bounds = InferredBounds::new();
-
- let source_method = if input.has_source() {
- let arms = input.variants.iter().map(|variant| {
- let ident = &variant.ident;
- if let Some(transparent_attr) = &variant.attrs.transparent {
- let only_field = &variant.fields[0];
- if only_field.contains_generic {
- error_inferred_bounds.insert(only_field.ty, quote!(std::error::Error));
- }
- let member = &only_field.member;
- let source = quote_spanned! {transparent_attr.span=>
- std::error::Error::source(transparent.as_dyn_error())
- };
- quote! {
- #ty::#ident {#member: transparent} => #source,
- }
- } else if let Some(source_field) = variant.source_field() {
- let source = &source_field.member;
- if source_field.contains_generic {
- let ty = unoptional_type(source_field.ty);
- error_inferred_bounds.insert(ty, quote!(std::error::Error + 'static));
- }
- let asref = if type_is_option(source_field.ty) {
- Some(quote_spanned!(source.member_span()=> .as_ref()?))
- } else {
- None
- };
- let varsource = quote!(source);
- let dyn_error = quote_spanned! {source_field.source_span()=>
- #varsource #asref.as_dyn_error()
- };
- quote! {
- #ty::#ident {#source: #varsource, ..} => ::core::option::Option::Some(#dyn_error),
- }
- } else {
- quote! {
- #ty::#ident {..} => ::core::option::Option::None,
- }
- }
- });
- Some(quote! {
- fn source(&self) -> ::core::option::Option<&(dyn std::error::Error + 'static)> {
- use thiserror::__private::AsDynError as _;
- #[allow(deprecated)]
- match self {
- #(#arms)*
- }
- }
- })
- } else {
- None
- };
-
- let provide_method = if input.has_backtrace() {
- let request = quote!(request);
- let arms = input.variants.iter().map(|variant| {
- let ident = &variant.ident;
- match (variant.backtrace_field(), variant.source_field()) {
- (Some(backtrace_field), Some(source_field))
- if backtrace_field.attrs.backtrace.is_none() =>
- {
- let backtrace = &backtrace_field.member;
- let source = &source_field.member;
- let varsource = quote!(source);
- let source_provide = if type_is_option(source_field.ty) {
- quote_spanned! {source.member_span()=>
- if let ::core::option::Option::Some(source) = #varsource {
- source.thiserror_provide(#request);
- }
- }
- } else {
- quote_spanned! {source.member_span()=>
- #varsource.thiserror_provide(#request);
- }
- };
- let self_provide = if type_is_option(backtrace_field.ty) {
- quote! {
- if let ::core::option::Option::Some(backtrace) = backtrace {
- #request.provide_ref::<std::backtrace::Backtrace>(backtrace);
- }
- }
- } else {
- quote! {
- #request.provide_ref::<std::backtrace::Backtrace>(backtrace);
- }
- };
- quote! {
- #ty::#ident {
- #backtrace: backtrace,
- #source: #varsource,
- ..
- } => {
- use thiserror::__private::ThiserrorProvide as _;
- #source_provide
- #self_provide
- }
- }
- }
- (Some(backtrace_field), Some(source_field))
- if backtrace_field.member == source_field.member =>
- {
- let backtrace = &backtrace_field.member;
- let varsource = quote!(source);
- let source_provide = if type_is_option(source_field.ty) {
- quote_spanned! {backtrace.member_span()=>
- if let ::core::option::Option::Some(source) = #varsource {
- source.thiserror_provide(#request);
- }
- }
- } else {
- quote_spanned! {backtrace.member_span()=>
- #varsource.thiserror_provide(#request);
- }
- };
- quote! {
- #ty::#ident {#backtrace: #varsource, ..} => {
- use thiserror::__private::ThiserrorProvide as _;
- #source_provide
- }
- }
- }
- (Some(backtrace_field), _) => {
- let backtrace = &backtrace_field.member;
- let body = if type_is_option(backtrace_field.ty) {
- quote! {
- if let ::core::option::Option::Some(backtrace) = backtrace {
- #request.provide_ref::<std::backtrace::Backtrace>(backtrace);
- }
- }
- } else {
- quote! {
- #request.provide_ref::<std::backtrace::Backtrace>(backtrace);
- }
- };
- quote! {
- #ty::#ident {#backtrace: backtrace, ..} => {
- #body
- }
- }
- }
- (None, _) => quote! {
- #ty::#ident {..} => {}
- },
- }
- });
- Some(quote! {
- fn provide<'_request>(&'_request self, #request: &mut std::error::Request<'_request>) {
- #[allow(deprecated)]
- match self {
- #(#arms)*
- }
- }
- })
- } else {
- None
- };
-
- let display_impl = if input.has_display() {
- let mut display_inferred_bounds = InferredBounds::new();
- let has_bonus_display = input.variants.iter().any(|v| {
- v.attrs
- .display
- .as_ref()
- .map_or(false, |display| display.has_bonus_display)
- });
- let use_as_display = use_as_display(has_bonus_display);
- let void_deref = if input.variants.is_empty() {
- Some(quote!(*))
- } else {
- None
- };
- let arms = input.variants.iter().map(|variant| {
- let mut display_implied_bounds = Set::new();
- let display = match &variant.attrs.display {
- Some(display) => {
- display_implied_bounds = display.implied_bounds.clone();
- display.to_token_stream()
- }
- None => {
- let only_field = match &variant.fields[0].member {
- Member::Named(ident) => ident.clone(),
- Member::Unnamed(index) => format_ident!("_{}", index),
- };
- display_implied_bounds.insert((0, Trait::Display));
- quote!(::core::fmt::Display::fmt(#only_field, __formatter))
- }
- };
- for (field, bound) in display_implied_bounds {
- let field = &variant.fields[field];
- if field.contains_generic {
- display_inferred_bounds.insert(field.ty, bound);
- }
- }
- let ident = &variant.ident;
- let pat = fields_pat(&variant.fields);
- quote! {
- #ty::#ident #pat => #display
- }
- });
- let arms = arms.collect::<Vec<_>>();
- let display_where_clause = display_inferred_bounds.augment_where_clause(input.generics);
- Some(quote! {
- #[allow(unused_qualifications)]
- impl #impl_generics ::core::fmt::Display for #ty #ty_generics #display_where_clause {
- fn fmt(&self, __formatter: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
- #use_as_display
- #[allow(unused_variables, deprecated, clippy::used_underscore_binding)]
- match #void_deref self {
- #(#arms,)*
- }
- }
- }
- })
- } else {
- None
- };
-
- let from_impls = input.variants.iter().filter_map(|variant| {
- let from_field = variant.from_field()?;
- let backtrace_field = variant.distinct_backtrace_field();
- let variant = &variant.ident;
- let from = unoptional_type(from_field.ty);
- let body = from_initializer(from_field, backtrace_field);
- Some(quote! {
- #[allow(unused_qualifications)]
- impl #impl_generics ::core::convert::From<#from> for #ty #ty_generics #where_clause {
- #[allow(deprecated)]
- fn from(source: #from) -> Self {
- #ty::#variant #body
- }
- }
- })
- });
-
- if input.generics.type_params().next().is_some() {
- let self_token = <Token![Self]>::default();
- error_inferred_bounds.insert(self_token, Trait::Debug);
- error_inferred_bounds.insert(self_token, Trait::Display);
- }
- let error_where_clause = error_inferred_bounds.augment_where_clause(input.generics);
-
- quote! {
- #[allow(unused_qualifications)]
- impl #impl_generics std::error::Error for #ty #ty_generics #error_where_clause {
- #source_method
- #provide_method
- }
- #display_impl
- #(#from_impls)*
- }
-}
-
-fn fields_pat(fields: &[Field]) -> TokenStream {
- let mut members = fields.iter().map(|field| &field.member).peekable();
- match members.peek() {
- Some(Member::Named(_)) => quote!({ #(#members),* }),
- Some(Member::Unnamed(_)) => {
- let vars = members.map(|member| match member {
- Member::Unnamed(member) => format_ident!("_{}", member),
- Member::Named(_) => unreachable!(),
- });
- quote!((#(#vars),*))
- }
- None => quote!({}),
- }
-}
-
-fn use_as_display(needs_as_display: bool) -> Option<TokenStream> {
- if needs_as_display {
- Some(quote! {
- use thiserror::__private::AsDisplay as _;
- })
- } else {
- None
- }
-}
-
-fn from_initializer(from_field: &Field, backtrace_field: Option<&Field>) -> TokenStream {
- let from_member = &from_field.member;
- let some_source = if type_is_option(from_field.ty) {
- quote!(::core::option::Option::Some(source))
- } else {
- quote!(source)
- };
- let backtrace = backtrace_field.map(|backtrace_field| {
- let backtrace_member = &backtrace_field.member;
- if type_is_option(backtrace_field.ty) {
- quote! {
- #backtrace_member: ::core::option::Option::Some(std::backtrace::Backtrace::capture()),
- }
- } else {
- quote! {
- #backtrace_member: ::core::convert::From::from(std::backtrace::Backtrace::capture()),
- }
- }
- });
- quote!({
- #from_member: #some_source,
- #backtrace
- })
-}
-
-fn type_is_option(ty: &Type) -> bool {
- type_parameter_of_option(ty).is_some()
-}
-
-fn unoptional_type(ty: &Type) -> TokenStream {
- let unoptional = type_parameter_of_option(ty).unwrap_or(ty);
- quote!(#unoptional)
-}
-
-fn type_parameter_of_option(ty: &Type) -> Option<&Type> {
- let path = match ty {
- Type::Path(ty) => &ty.path,
- _ => return None,
- };
-
- let last = path.segments.last().unwrap();
- if last.ident != "Option" {
- return None;
- }
-
- let bracketed = match &last.arguments {
- PathArguments::AngleBracketed(bracketed) => bracketed,
- _ => return None,
- };
-
- if bracketed.args.len() != 1 {
- return None;
- }
-
- match &bracketed.args[0] {
- GenericArgument::Type(arg) => Some(arg),
- _ => None,
- }
-}
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