thiserror-impl-1.0.50/.cargo_vcs_info.json0000644000000001420000000000100140740ustar { "git": { "sha1": "a7d220d7915fb888413aa7978efd70f7006bda9d" }, "path_in_vcs": "impl" }thiserror-impl-1.0.50/Cargo.toml0000644000000017730000000000100121050ustar # THIS FILE IS AUTOMATICALLY GENERATED BY CARGO # # When uploading crates to the registry Cargo will automatically # "normalize" Cargo.toml files for maximal compatibility # with all versions of Cargo and also rewrite `path` dependencies # to registry (e.g., crates.io) dependencies. # # If you are reading this file be aware that the original Cargo.toml # will likely look very different (and much more reasonable). # See Cargo.toml.orig for the original contents. [package] edition = "2021" rust-version = "1.56" name = "thiserror-impl" version = "1.0.50" authors = ["David Tolnay "] description = "Implementation detail of the `thiserror` crate" license = "MIT OR Apache-2.0" repository = "https://github.com/dtolnay/thiserror" [package.metadata.docs.rs] rustdoc-args = ["--generate-link-to-definition"] targets = ["x86_64-unknown-linux-gnu"] [lib] proc-macro = true [dependencies.proc-macro2] version = "1.0.63" [dependencies.quote] version = "1.0.29" [dependencies.syn] version = "2.0.23" thiserror-impl-1.0.50/Cargo.toml.orig000064400000000000000000000007601046102023000155610ustar 00000000000000[package] name = "thiserror-impl" version = "1.0.50" authors = ["David Tolnay "] description = "Implementation detail of the `thiserror` crate" edition = "2021" license = "MIT OR Apache-2.0" repository = "https://github.com/dtolnay/thiserror" rust-version = "1.56" [lib] proc-macro = true [dependencies] proc-macro2 = "1.0.63" quote = "1.0.29" syn = "2.0.23" [package.metadata.docs.rs] targets = ["x86_64-unknown-linux-gnu"] rustdoc-args = ["--generate-link-to-definition"] thiserror-impl-1.0.50/LICENSE-APACHE000064400000000000000000000227731046102023000146260ustar 00000000000000 Apache License Version 2.0, January 2004 http://www.apache.org/licenses/ TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION 1. 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END OF TERMS AND CONDITIONS thiserror-impl-1.0.50/LICENSE-MIT000064400000000000000000000017771046102023000143370ustar 00000000000000Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. thiserror-impl-1.0.50/src/ast.rs000064400000000000000000000111521046102023000146130ustar 00000000000000use crate::attr::{self, Attrs}; use crate::generics::ParamsInScope; use proc_macro2::Span; use syn::{ Data, DataEnum, DataStruct, DeriveInput, Error, Fields, Generics, Ident, Index, Member, Result, Type, }; pub enum Input<'a> { Struct(Struct<'a>), Enum(Enum<'a>), } pub struct Struct<'a> { pub original: &'a DeriveInput, pub attrs: Attrs<'a>, pub ident: Ident, pub generics: &'a Generics, pub fields: Vec>, } pub struct Enum<'a> { pub original: &'a DeriveInput, pub attrs: Attrs<'a>, pub ident: Ident, pub generics: &'a Generics, pub variants: Vec>, } pub struct Variant<'a> { pub original: &'a syn::Variant, pub attrs: Attrs<'a>, pub ident: Ident, pub fields: Vec>, } pub struct Field<'a> { pub original: &'a syn::Field, pub attrs: Attrs<'a>, pub member: Member, pub ty: &'a Type, pub contains_generic: bool, } impl<'a> Input<'a> { pub fn from_syn(node: &'a DeriveInput) -> Result { match &node.data { Data::Struct(data) => Struct::from_syn(node, data).map(Input::Struct), Data::Enum(data) => Enum::from_syn(node, data).map(Input::Enum), Data::Union(_) => Err(Error::new_spanned( node, "union as errors are not supported", )), } } } impl<'a> Struct<'a> { fn from_syn(node: &'a DeriveInput, data: &'a DataStruct) -> Result { let mut attrs = attr::get(&node.attrs)?; let scope = ParamsInScope::new(&node.generics); let span = attrs.span().unwrap_or_else(Span::call_site); let fields = Field::multiple_from_syn(&data.fields, &scope, span)?; if let Some(display) = &mut attrs.display { display.expand_shorthand(&fields); } Ok(Struct { original: node, attrs, ident: node.ident.clone(), generics: &node.generics, fields, }) } } impl<'a> Enum<'a> { fn from_syn(node: &'a DeriveInput, data: &'a DataEnum) -> Result { let attrs = attr::get(&node.attrs)?; let scope = ParamsInScope::new(&node.generics); let span = attrs.span().unwrap_or_else(Span::call_site); let variants = data .variants .iter() .map(|node| { let mut variant = Variant::from_syn(node, &scope, span)?; if let display @ None = &mut variant.attrs.display { *display = attrs.display.clone(); } if let Some(display) = &mut variant.attrs.display { display.expand_shorthand(&variant.fields); } else if variant.attrs.transparent.is_none() { variant.attrs.transparent = attrs.transparent; } Ok(variant) }) .collect::>()?; Ok(Enum { original: node, attrs, ident: node.ident.clone(), generics: &node.generics, variants, }) } } impl<'a> Variant<'a> { fn from_syn(node: &'a syn::Variant, scope: &ParamsInScope<'a>, span: Span) -> Result { let attrs = attr::get(&node.attrs)?; let span = attrs.span().unwrap_or(span); Ok(Variant { original: node, attrs, ident: node.ident.clone(), fields: Field::multiple_from_syn(&node.fields, scope, span)?, }) } } impl<'a> Field<'a> { fn multiple_from_syn( fields: &'a Fields, scope: &ParamsInScope<'a>, span: Span, ) -> Result> { fields .iter() .enumerate() .map(|(i, field)| Field::from_syn(i, field, scope, span)) .collect() } fn from_syn( i: usize, node: &'a syn::Field, scope: &ParamsInScope<'a>, span: Span, ) -> Result { Ok(Field { original: node, attrs: attr::get(&node.attrs)?, member: node.ident.clone().map(Member::Named).unwrap_or_else(|| { Member::Unnamed(Index { index: i as u32, span, }) }), ty: &node.ty, contains_generic: scope.intersects(&node.ty), }) } } impl Attrs<'_> { pub fn span(&self) -> Option { if let Some(display) = &self.display { Some(display.fmt.span()) } else if let Some(transparent) = &self.transparent { Some(transparent.span) } else { None } } } thiserror-impl-1.0.50/src/attr.rs000064400000000000000000000151631046102023000150040ustar 00000000000000use proc_macro2::{Delimiter, Group, Span, TokenStream, TokenTree}; use quote::{format_ident, quote, ToTokens}; use std::collections::BTreeSet as Set; use syn::parse::ParseStream; use syn::{ braced, bracketed, parenthesized, token, Attribute, Error, Ident, Index, LitInt, LitStr, Meta, Result, Token, }; pub struct Attrs<'a> { pub display: Option>, pub source: Option<&'a Attribute>, pub backtrace: Option<&'a Attribute>, pub from: Option<&'a Attribute>, pub transparent: Option>, } #[derive(Clone)] pub struct Display<'a> { pub original: &'a Attribute, pub fmt: LitStr, pub args: TokenStream, pub has_bonus_display: bool, pub implied_bounds: Set<(usize, Trait)>, } #[derive(Copy, Clone)] pub struct Transparent<'a> { pub original: &'a Attribute, pub span: Span, } #[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Debug)] pub enum Trait { Debug, Display, Octal, LowerHex, UpperHex, Pointer, Binary, LowerExp, UpperExp, } pub fn get(input: &[Attribute]) -> Result { let mut attrs = Attrs { display: None, source: None, backtrace: None, from: None, transparent: None, }; for attr in input { if attr.path().is_ident("error") { parse_error_attribute(&mut attrs, attr)?; } else if attr.path().is_ident("source") { attr.meta.require_path_only()?; if attrs.source.is_some() { return Err(Error::new_spanned(attr, "duplicate #[source] attribute")); } attrs.source = Some(attr); } else if attr.path().is_ident("backtrace") { attr.meta.require_path_only()?; if attrs.backtrace.is_some() { return Err(Error::new_spanned(attr, "duplicate #[backtrace] attribute")); } attrs.backtrace = Some(attr); } else if attr.path().is_ident("from") { match attr.meta { Meta::Path(_) => {} Meta::List(_) | Meta::NameValue(_) => { // Assume this is meant for derive_more crate or something. continue; } } if attrs.from.is_some() { return Err(Error::new_spanned(attr, "duplicate #[from] attribute")); } attrs.from = Some(attr); } } Ok(attrs) } fn parse_error_attribute<'a>(attrs: &mut Attrs<'a>, attr: &'a Attribute) -> Result<()> { syn::custom_keyword!(transparent); attr.parse_args_with(|input: ParseStream| { if let Some(kw) = input.parse::>()? { if attrs.transparent.is_some() { return Err(Error::new_spanned( attr, "duplicate #[error(transparent)] attribute", )); } attrs.transparent = Some(Transparent { original: attr, span: kw.span, }); return Ok(()); } let display = Display { original: attr, fmt: input.parse()?, args: parse_token_expr(input, false)?, has_bonus_display: false, implied_bounds: Set::new(), }; if attrs.display.is_some() { return Err(Error::new_spanned( attr, "only one #[error(...)] attribute is allowed", )); } attrs.display = Some(display); Ok(()) }) } fn parse_token_expr(input: ParseStream, mut begin_expr: bool) -> Result { let mut tokens = Vec::new(); while !input.is_empty() { if begin_expr && input.peek(Token![.]) { if input.peek2(Ident) { input.parse::()?; begin_expr = false; continue; } if input.peek2(LitInt) { input.parse::()?; let int: Index = input.parse()?; let ident = format_ident!("_{}", int.index, span = int.span); tokens.push(TokenTree::Ident(ident)); begin_expr = false; continue; } } begin_expr = input.peek(Token![break]) || input.peek(Token![continue]) || input.peek(Token![if]) || input.peek(Token![in]) || input.peek(Token![match]) || input.peek(Token![mut]) || input.peek(Token![return]) || input.peek(Token![while]) || input.peek(Token![+]) || input.peek(Token![&]) || input.peek(Token![!]) || input.peek(Token![^]) || input.peek(Token![,]) || input.peek(Token![/]) || input.peek(Token![=]) || input.peek(Token![>]) || input.peek(Token![<]) || input.peek(Token![|]) || input.peek(Token![%]) || input.peek(Token![;]) || input.peek(Token![*]) || input.peek(Token![-]); let token: TokenTree = if input.peek(token::Paren) { let content; let delimiter = parenthesized!(content in input); let nested = parse_token_expr(&content, true)?; let mut group = Group::new(Delimiter::Parenthesis, nested); group.set_span(delimiter.span.join()); TokenTree::Group(group) } else if input.peek(token::Brace) { let content; let delimiter = braced!(content in input); let nested = parse_token_expr(&content, true)?; let mut group = Group::new(Delimiter::Brace, nested); group.set_span(delimiter.span.join()); TokenTree::Group(group) } else if input.peek(token::Bracket) { let content; let delimiter = bracketed!(content in input); let nested = parse_token_expr(&content, true)?; let mut group = Group::new(Delimiter::Bracket, nested); group.set_span(delimiter.span.join()); TokenTree::Group(group) } else { input.parse()? }; tokens.push(token); } Ok(TokenStream::from_iter(tokens)) } impl ToTokens for Display<'_> { fn to_tokens(&self, tokens: &mut TokenStream) { let fmt = &self.fmt; let args = &self.args; tokens.extend(quote! { ::core::write!(__formatter, #fmt #args) }); } } impl ToTokens for Trait { fn to_tokens(&self, tokens: &mut TokenStream) { let trait_name = format_ident!("{}", format!("{:?}", self)); tokens.extend(quote!(::core::fmt::#trait_name)); } } thiserror-impl-1.0.50/src/expand.rs000064400000000000000000000506141046102023000153110ustar 00000000000000use 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::{ Data, DeriveInput, GenericArgument, Member, PathArguments, Result, Token, Type, Visibility, }; pub fn derive(node: &DeriveInput) -> Result { let input = Input::from_syn(node)?; input.validate()?; Ok(match input { Input::Struct(input) => impl_struct(input), Input::Enum(input) => impl_enum(input), }) } 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; #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::(backtrace); } }) } else { Some(quote! { #request.provide_ref::(&self.#backtrace); }) }; quote! { use thiserror::__private::ThiserrorProvide; #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::(backtrace); } } } else { quote! { #request.provide_ref::(&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 } } } }); let error_trait = spanned_error_trait(input.original); if input.generics.type_params().next().is_some() { let self_token = ::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 #error_trait 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; #[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::(backtrace); } } } else { quote! { #request.provide_ref::(backtrace); } }; quote! { #ty::#ident { #backtrace: backtrace, #source: #varsource, .. } => { use thiserror::__private::ThiserrorProvide; #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; #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::(backtrace); } } } else { quote! { #request.provide_ref::(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::>(); 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 } } }) }); let error_trait = spanned_error_trait(input.original); if input.generics.type_params().next().is_some() { let self_token = ::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 #error_trait 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 { 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, } } fn spanned_error_trait(input: &DeriveInput) -> TokenStream { let vis_span = match &input.vis { Visibility::Public(vis) => Some(vis.span), Visibility::Restricted(vis) => Some(vis.pub_token.span), Visibility::Inherited => None, }; let data_span = match &input.data { Data::Struct(data) => data.struct_token.span, Data::Enum(data) => data.enum_token.span, Data::Union(data) => data.union_token.span, }; let first_span = vis_span.unwrap_or(data_span); let last_span = input.ident.span(); let path = quote_spanned!(first_span=> std::error::); let error = quote_spanned!(last_span=> Error); quote!(#path #error) } thiserror-impl-1.0.50/src/fmt.rs000064400000000000000000000135571046102023000146250ustar 00000000000000use crate::ast::Field; use crate::attr::{Display, Trait}; use proc_macro2::TokenTree; use quote::{format_ident, quote_spanned}; use std::collections::{BTreeSet as Set, HashMap as Map}; use syn::ext::IdentExt; use syn::parse::{ParseStream, Parser}; use syn::{Ident, Index, LitStr, Member, Result, Token}; impl Display<'_> { // Transform `"error {var}"` to `"error {}", var`. pub fn expand_shorthand(&mut self, fields: &[Field]) { let raw_args = self.args.clone(); let mut named_args = explicit_named_args.parse2(raw_args).unwrap(); let mut member_index = Map::new(); for (i, field) in fields.iter().enumerate() { member_index.insert(&field.member, i); } let span = self.fmt.span(); let fmt = self.fmt.value(); let mut read = fmt.as_str(); let mut out = String::new(); let mut args = self.args.clone(); let mut has_bonus_display = false; let mut implied_bounds = Set::new(); let mut has_trailing_comma = false; if let Some(TokenTree::Punct(punct)) = args.clone().into_iter().last() { if punct.as_char() == ',' { has_trailing_comma = true; } } while let Some(brace) = read.find('{') { out += &read[..brace + 1]; read = &read[brace + 1..]; if read.starts_with('{') { out.push('{'); read = &read[1..]; continue; } let next = match read.chars().next() { Some(next) => next, None => return, }; let member = match next { '0'..='9' => { let int = take_int(&mut read); let member = match int.parse::() { Ok(index) => Member::Unnamed(Index { index, span }), Err(_) => return, }; if !member_index.contains_key(&member) { out += ∫ continue; } member } 'a'..='z' | 'A'..='Z' | '_' => { let mut ident = take_ident(&mut read); ident.set_span(span); Member::Named(ident) } _ => continue, }; if let Some(&field) = member_index.get(&member) { let end_spec = match read.find('}') { Some(end_spec) => end_spec, None => return, }; let bound = match read[..end_spec].chars().next_back() { Some('?') => Trait::Debug, Some('o') => Trait::Octal, Some('x') => Trait::LowerHex, Some('X') => Trait::UpperHex, Some('p') => Trait::Pointer, Some('b') => Trait::Binary, Some('e') => Trait::LowerExp, Some('E') => Trait::UpperExp, Some(_) | None => Trait::Display, }; implied_bounds.insert((field, bound)); } let local = match &member { Member::Unnamed(index) => format_ident!("_{}", index), Member::Named(ident) => ident.clone(), }; let mut formatvar = local.clone(); if formatvar.to_string().starts_with("r#") { formatvar = format_ident!("r_{}", formatvar); } if formatvar.to_string().starts_with('_') { // Work around leading underscore being rejected by 1.40 and // older compilers. https://github.com/rust-lang/rust/pull/66847 formatvar = format_ident!("field_{}", formatvar); } out += &formatvar.to_string(); if !named_args.insert(formatvar.clone()) { // Already specified in the format argument list. continue; } if !has_trailing_comma { args.extend(quote_spanned!(span=> ,)); } args.extend(quote_spanned!(span=> #formatvar = #local)); if read.starts_with('}') && member_index.contains_key(&member) { has_bonus_display = true; args.extend(quote_spanned!(span=> .as_display())); } has_trailing_comma = false; } out += read; self.fmt = LitStr::new(&out, self.fmt.span()); self.args = args; self.has_bonus_display = has_bonus_display; self.implied_bounds = implied_bounds; } } fn explicit_named_args(input: ParseStream) -> Result> { let mut named_args = Set::new(); while !input.is_empty() { if input.peek(Token![,]) && input.peek2(Ident::peek_any) && input.peek3(Token![=]) { input.parse::()?; let ident = input.call(Ident::parse_any)?; input.parse::()?; named_args.insert(ident); } else { input.parse::()?; } } Ok(named_args) } fn take_int(read: &mut &str) -> String { let mut int = String::new(); for (i, ch) in read.char_indices() { match ch { '0'..='9' => int.push(ch), _ => { *read = &read[i..]; break; } } } int } fn take_ident(read: &mut &str) -> Ident { let mut ident = String::new(); let raw = read.starts_with("r#"); if raw { ident.push_str("r#"); *read = &read[2..]; } for (i, ch) in read.char_indices() { match ch { 'a'..='z' | 'A'..='Z' | '0'..='9' | '_' => ident.push(ch), _ => { *read = &read[i..]; break; } } } Ident::parse_any.parse_str(&ident).unwrap() } thiserror-impl-1.0.50/src/generics.rs000064400000000000000000000051131046102023000156230ustar 00000000000000use proc_macro2::TokenStream; use quote::ToTokens; use std::collections::btree_map::Entry; use std::collections::{BTreeMap as Map, BTreeSet as Set}; use syn::punctuated::Punctuated; use syn::{parse_quote, GenericArgument, Generics, Ident, PathArguments, Token, Type, WhereClause}; pub struct ParamsInScope<'a> { names: Set<&'a Ident>, } impl<'a> ParamsInScope<'a> { pub fn new(generics: &'a Generics) -> Self { ParamsInScope { names: generics.type_params().map(|param| ¶m.ident).collect(), } } pub fn intersects(&self, ty: &Type) -> bool { let mut found = false; crawl(self, ty, &mut found); found } } fn crawl(in_scope: &ParamsInScope, ty: &Type, found: &mut bool) { if let Type::Path(ty) = ty { if ty.qself.is_none() { if let Some(ident) = ty.path.get_ident() { if in_scope.names.contains(ident) { *found = true; } } } for segment in &ty.path.segments { if let PathArguments::AngleBracketed(arguments) = &segment.arguments { for arg in &arguments.args { if let GenericArgument::Type(ty) = arg { crawl(in_scope, ty, found); } } } } } } pub struct InferredBounds { bounds: Map, Punctuated)>, order: Vec, } impl InferredBounds { pub fn new() -> Self { InferredBounds { bounds: Map::new(), order: Vec::new(), } } #[allow(clippy::type_repetition_in_bounds, clippy::trait_duplication_in_bounds)] // clippy bug: https://github.com/rust-lang/rust-clippy/issues/8771 pub fn insert(&mut self, ty: impl ToTokens, bound: impl ToTokens) { let ty = ty.to_token_stream(); let bound = bound.to_token_stream(); let entry = self.bounds.entry(ty.to_string()); if let Entry::Vacant(_) = entry { self.order.push(ty); } let (set, tokens) = entry.or_default(); if set.insert(bound.to_string()) { tokens.push(bound); } } pub fn augment_where_clause(&self, generics: &Generics) -> WhereClause { let mut generics = generics.clone(); let where_clause = generics.make_where_clause(); for ty in &self.order { let (_set, bounds) = &self.bounds[&ty.to_string()]; where_clause.predicates.push(parse_quote!(#ty: #bounds)); } generics.where_clause.unwrap() } } thiserror-impl-1.0.50/src/lib.rs000064400000000000000000000016261046102023000145770ustar 00000000000000#![allow( clippy::blocks_in_if_conditions, clippy::cast_lossless, clippy::cast_possible_truncation, clippy::manual_find, clippy::manual_let_else, clippy::manual_map, clippy::map_unwrap_or, clippy::module_name_repetitions, clippy::needless_pass_by_value, clippy::option_if_let_else, clippy::range_plus_one, clippy::single_match_else, clippy::too_many_lines, clippy::wrong_self_convention )] extern crate proc_macro; mod ast; mod attr; mod expand; mod fmt; mod generics; mod prop; mod span; mod valid; use proc_macro::TokenStream; use syn::{parse_macro_input, DeriveInput}; #[proc_macro_derive(Error, attributes(backtrace, error, from, source))] pub fn derive_error(input: TokenStream) -> TokenStream { let input = parse_macro_input!(input as DeriveInput); expand::derive(&input) .unwrap_or_else(|err| err.to_compile_error()) .into() } thiserror-impl-1.0.50/src/prop.rs000064400000000000000000000075731046102023000150200ustar 00000000000000use crate::ast::{Enum, Field, Struct, Variant}; use crate::span::MemberSpan; use proc_macro2::Span; use syn::{Member, Type}; impl Struct<'_> { pub(crate) fn from_field(&self) -> Option<&Field> { from_field(&self.fields) } pub(crate) fn source_field(&self) -> Option<&Field> { source_field(&self.fields) } pub(crate) fn backtrace_field(&self) -> Option<&Field> { backtrace_field(&self.fields) } pub(crate) fn distinct_backtrace_field(&self) -> Option<&Field> { let backtrace_field = self.backtrace_field()?; distinct_backtrace_field(backtrace_field, self.from_field()) } } impl Enum<'_> { pub(crate) fn has_source(&self) -> bool { self.variants .iter() .any(|variant| variant.source_field().is_some() || variant.attrs.transparent.is_some()) } pub(crate) fn has_backtrace(&self) -> bool { self.variants .iter() .any(|variant| variant.backtrace_field().is_some()) } pub(crate) fn has_display(&self) -> bool { self.attrs.display.is_some() || self.attrs.transparent.is_some() || self .variants .iter() .any(|variant| variant.attrs.display.is_some()) || self .variants .iter() .all(|variant| variant.attrs.transparent.is_some()) } } impl Variant<'_> { pub(crate) fn from_field(&self) -> Option<&Field> { from_field(&self.fields) } pub(crate) fn source_field(&self) -> Option<&Field> { source_field(&self.fields) } pub(crate) fn backtrace_field(&self) -> Option<&Field> { backtrace_field(&self.fields) } pub(crate) fn distinct_backtrace_field(&self) -> Option<&Field> { let backtrace_field = self.backtrace_field()?; distinct_backtrace_field(backtrace_field, self.from_field()) } } impl Field<'_> { pub(crate) fn is_backtrace(&self) -> bool { type_is_backtrace(self.ty) } pub(crate) fn source_span(&self) -> Span { if let Some(source_attr) = &self.attrs.source { source_attr.path().get_ident().unwrap().span() } else if let Some(from_attr) = &self.attrs.from { from_attr.path().get_ident().unwrap().span() } else { self.member.member_span() } } } fn from_field<'a, 'b>(fields: &'a [Field<'b>]) -> Option<&'a Field<'b>> { for field in fields { if field.attrs.from.is_some() { return Some(field); } } None } fn source_field<'a, 'b>(fields: &'a [Field<'b>]) -> Option<&'a Field<'b>> { for field in fields { if field.attrs.from.is_some() || field.attrs.source.is_some() { return Some(field); } } for field in fields { match &field.member { Member::Named(ident) if ident == "source" => return Some(field), _ => {} } } None } fn backtrace_field<'a, 'b>(fields: &'a [Field<'b>]) -> Option<&'a Field<'b>> { for field in fields { if field.attrs.backtrace.is_some() { return Some(field); } } for field in fields { if field.is_backtrace() { return Some(field); } } None } // The #[backtrace] field, if it is not the same as the #[from] field. fn distinct_backtrace_field<'a, 'b>( backtrace_field: &'a Field<'b>, from_field: Option<&Field>, ) -> Option<&'a Field<'b>> { if from_field.map_or(false, |from_field| { from_field.member == backtrace_field.member }) { None } else { Some(backtrace_field) } } fn type_is_backtrace(ty: &Type) -> bool { let path = match ty { Type::Path(ty) => &ty.path, _ => return false, }; let last = path.segments.last().unwrap(); last.ident == "Backtrace" && last.arguments.is_empty() } thiserror-impl-1.0.50/src/span.rs000064400000000000000000000004621046102023000147670ustar 00000000000000use proc_macro2::Span; use syn::Member; pub trait MemberSpan { fn member_span(&self) -> Span; } impl MemberSpan for Member { fn member_span(&self) -> Span { match self { Member::Named(ident) => ident.span(), Member::Unnamed(index) => index.span, } } } thiserror-impl-1.0.50/src/valid.rs000064400000000000000000000200461046102023000151250ustar 00000000000000use crate::ast::{Enum, Field, Input, Struct, Variant}; use crate::attr::Attrs; use quote::ToTokens; use std::collections::BTreeSet as Set; use syn::{Error, GenericArgument, Member, PathArguments, Result, Type}; impl Input<'_> { pub(crate) fn validate(&self) -> Result<()> { match self { Input::Struct(input) => input.validate(), Input::Enum(input) => input.validate(), } } } impl Struct<'_> { fn validate(&self) -> Result<()> { check_non_field_attrs(&self.attrs)?; if let Some(transparent) = self.attrs.transparent { if self.fields.len() != 1 { return Err(Error::new_spanned( transparent.original, "#[error(transparent)] requires exactly one field", )); } if let Some(source) = self.fields.iter().find_map(|f| f.attrs.source) { return Err(Error::new_spanned( source, "transparent error struct can't contain #[source]", )); } } check_field_attrs(&self.fields)?; for field in &self.fields { field.validate()?; } Ok(()) } } impl Enum<'_> { fn validate(&self) -> Result<()> { check_non_field_attrs(&self.attrs)?; let has_display = self.has_display(); for variant in &self.variants { variant.validate()?; if has_display && variant.attrs.display.is_none() && variant.attrs.transparent.is_none() { return Err(Error::new_spanned( variant.original, "missing #[error(\"...\")] display attribute", )); } } let mut from_types = Set::new(); for variant in &self.variants { if let Some(from_field) = variant.from_field() { let repr = from_field.ty.to_token_stream().to_string(); if !from_types.insert(repr) { return Err(Error::new_spanned( from_field.original, "cannot derive From because another variant has the same source type", )); } } } Ok(()) } } impl Variant<'_> { fn validate(&self) -> Result<()> { check_non_field_attrs(&self.attrs)?; if self.attrs.transparent.is_some() { if self.fields.len() != 1 { return Err(Error::new_spanned( self.original, "#[error(transparent)] requires exactly one field", )); } if let Some(source) = self.fields.iter().find_map(|f| f.attrs.source) { return Err(Error::new_spanned( source, "transparent variant can't contain #[source]", )); } } check_field_attrs(&self.fields)?; for field in &self.fields { field.validate()?; } Ok(()) } } impl Field<'_> { fn validate(&self) -> Result<()> { if let Some(display) = &self.attrs.display { return Err(Error::new_spanned( display.original, "not expected here; the #[error(...)] attribute belongs on top of a struct or an enum variant", )); } Ok(()) } } fn check_non_field_attrs(attrs: &Attrs) -> Result<()> { if let Some(from) = &attrs.from { return Err(Error::new_spanned( from, "not expected here; the #[from] attribute belongs on a specific field", )); } if let Some(source) = &attrs.source { return Err(Error::new_spanned( source, "not expected here; the #[source] attribute belongs on a specific field", )); } if let Some(backtrace) = &attrs.backtrace { return Err(Error::new_spanned( backtrace, "not expected here; the #[backtrace] attribute belongs on a specific field", )); } if let Some(display) = &attrs.display { if attrs.transparent.is_some() { return Err(Error::new_spanned( display.original, "cannot have both #[error(transparent)] and a display attribute", )); } } Ok(()) } fn check_field_attrs(fields: &[Field]) -> Result<()> { let mut from_field = None; let mut source_field = None; let mut backtrace_field = None; let mut has_backtrace = false; for field in fields { if let Some(from) = field.attrs.from { if from_field.is_some() { return Err(Error::new_spanned(from, "duplicate #[from] attribute")); } from_field = Some(field); } if let Some(source) = field.attrs.source { if source_field.is_some() { return Err(Error::new_spanned(source, "duplicate #[source] attribute")); } source_field = Some(field); } if let Some(backtrace) = field.attrs.backtrace { if backtrace_field.is_some() { return Err(Error::new_spanned( backtrace, "duplicate #[backtrace] attribute", )); } backtrace_field = Some(field); has_backtrace = true; } if let Some(transparent) = field.attrs.transparent { return Err(Error::new_spanned( transparent.original, "#[error(transparent)] needs to go outside the enum or struct, not on an individual field", )); } has_backtrace |= field.is_backtrace(); } if let (Some(from_field), Some(source_field)) = (from_field, source_field) { if !same_member(from_field, source_field) { return Err(Error::new_spanned( from_field.attrs.from, "#[from] is only supported on the source field, not any other field", )); } } if let Some(from_field) = from_field { let max_expected_fields = match backtrace_field { Some(backtrace_field) => 1 + !same_member(from_field, backtrace_field) as usize, None => 1 + has_backtrace as usize, }; if fields.len() > max_expected_fields { return Err(Error::new_spanned( from_field.attrs.from, "deriving From requires no fields other than source and backtrace", )); } } if let Some(source_field) = source_field.or(from_field) { if contains_non_static_lifetime(source_field.ty) { return Err(Error::new_spanned( &source_field.original.ty, "non-static lifetimes are not allowed in the source of an error, because std::error::Error requires the source is dyn Error + 'static", )); } } Ok(()) } fn same_member(one: &Field, two: &Field) -> bool { match (&one.member, &two.member) { (Member::Named(one), Member::Named(two)) => one == two, (Member::Unnamed(one), Member::Unnamed(two)) => one.index == two.index, _ => unreachable!(), } } fn contains_non_static_lifetime(ty: &Type) -> bool { match ty { Type::Path(ty) => { let bracketed = match &ty.path.segments.last().unwrap().arguments { PathArguments::AngleBracketed(bracketed) => bracketed, _ => return false, }; for arg in &bracketed.args { match arg { GenericArgument::Type(ty) if contains_non_static_lifetime(ty) => return true, GenericArgument::Lifetime(lifetime) if lifetime.ident != "static" => { return true } _ => {} } } false } Type::Reference(ty) => ty .lifetime .as_ref() .map_or(false, |lifetime| lifetime.ident != "static"), _ => false, // maybe implement later if there are common other cases } }