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-rw-r--r--vendor/thiserror-impl/src/ast.rs161
1 files changed, 161 insertions, 0 deletions
diff --git a/vendor/thiserror-impl/src/ast.rs b/vendor/thiserror-impl/src/ast.rs
new file mode 100644
index 0000000..9e06928
--- /dev/null
+++ b/vendor/thiserror-impl/src/ast.rs
@@ -0,0 +1,161 @@
+use 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 attrs: Attrs<'a>,
+ pub ident: Ident,
+ pub generics: &'a Generics,
+ pub fields: Vec<Field<'a>>,
+}
+
+pub struct Enum<'a> {
+ pub attrs: Attrs<'a>,
+ pub ident: Ident,
+ pub generics: &'a Generics,
+ pub variants: Vec<Variant<'a>>,
+}
+
+pub struct Variant<'a> {
+ pub original: &'a syn::Variant,
+ pub attrs: Attrs<'a>,
+ pub ident: Ident,
+ pub fields: Vec<Field<'a>>,
+}
+
+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<Self> {
+ 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<Self> {
+ 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 {
+ attrs,
+ ident: node.ident.clone(),
+ generics: &node.generics,
+ fields,
+ })
+ }
+}
+
+impl<'a> Enum<'a> {
+ fn from_syn(node: &'a DeriveInput, data: &'a DataEnum) -> Result<Self> {
+ 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::<Result<_>>()?;
+ Ok(Enum {
+ 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<Self> {
+ 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<Vec<Self>> {
+ 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<Self> {
+ 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<Span> {
+ if let Some(display) = &self.display {
+ Some(display.fmt.span())
+ } else if let Some(transparent) = &self.transparent {
+ Some(transparent.span)
+ } else {
+ None
+ }
+ }
+}