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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 19:33:14 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 19:33:14 +0000 |
commit | 36d22d82aa202bb199967e9512281e9a53db42c9 (patch) | |
tree | 105e8c98ddea1c1e4784a60a5a6410fa416be2de /third_party/rust/prost-derive/src/field/group.rs | |
parent | Initial commit. (diff) | |
download | firefox-esr-upstream.tar.xz firefox-esr-upstream.zip |
Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'third_party/rust/prost-derive/src/field/group.rs')
-rw-r--r-- | third_party/rust/prost-derive/src/field/group.rs | 134 |
1 files changed, 134 insertions, 0 deletions
diff --git a/third_party/rust/prost-derive/src/field/group.rs b/third_party/rust/prost-derive/src/field/group.rs new file mode 100644 index 0000000000..6396128802 --- /dev/null +++ b/third_party/rust/prost-derive/src/field/group.rs @@ -0,0 +1,134 @@ +use anyhow::{bail, Error}; +use proc_macro2::TokenStream; +use quote::{quote, ToTokens}; +use syn::Meta; + +use crate::field::{set_bool, set_option, tag_attr, word_attr, Label}; + +#[derive(Clone)] +pub struct Field { + pub label: Label, + pub tag: u32, +} + +impl Field { + pub fn new(attrs: &[Meta], inferred_tag: Option<u32>) -> Result<Option<Field>, Error> { + let mut group = false; + let mut label = None; + let mut tag = None; + let mut boxed = false; + + let mut unknown_attrs = Vec::new(); + + for attr in attrs { + if word_attr("group", attr) { + set_bool(&mut group, "duplicate group attributes")?; + } else if word_attr("boxed", attr) { + set_bool(&mut boxed, "duplicate boxed attributes")?; + } else if let Some(t) = tag_attr(attr)? { + set_option(&mut tag, t, "duplicate tag attributes")?; + } else if let Some(l) = Label::from_attr(attr) { + set_option(&mut label, l, "duplicate label attributes")?; + } else { + unknown_attrs.push(attr); + } + } + + if !group { + return Ok(None); + } + + match unknown_attrs.len() { + 0 => (), + 1 => bail!("unknown attribute for group field: {:?}", unknown_attrs[0]), + _ => bail!("unknown attributes for group field: {:?}", unknown_attrs), + } + + let tag = match tag.or(inferred_tag) { + Some(tag) => tag, + None => bail!("group field is missing a tag attribute"), + }; + + Ok(Some(Field { + label: label.unwrap_or(Label::Optional), + tag, + })) + } + + pub fn new_oneof(attrs: &[Meta]) -> Result<Option<Field>, Error> { + if let Some(mut field) = Field::new(attrs, None)? { + if let Some(attr) = attrs.iter().find(|attr| Label::from_attr(attr).is_some()) { + bail!( + "invalid attribute for oneof field: {}", + attr.path().into_token_stream() + ); + } + field.label = Label::Required; + Ok(Some(field)) + } else { + Ok(None) + } + } + + pub fn encode(&self, ident: TokenStream) -> TokenStream { + let tag = self.tag; + match self.label { + Label::Optional => quote! { + if let Some(ref msg) = #ident { + ::prost::encoding::group::encode(#tag, msg, buf); + } + }, + Label::Required => quote! { + ::prost::encoding::group::encode(#tag, &#ident, buf); + }, + Label::Repeated => quote! { + for msg in &#ident { + ::prost::encoding::group::encode(#tag, msg, buf); + } + }, + } + } + + pub fn merge(&self, ident: TokenStream) -> TokenStream { + match self.label { + Label::Optional => quote! { + ::prost::encoding::group::merge( + tag, + wire_type, + #ident.get_or_insert_with(Default::default), + buf, + ctx, + ) + }, + Label::Required => quote! { + ::prost::encoding::group::merge(tag, wire_type, #ident, buf, ctx) + }, + Label::Repeated => quote! { + ::prost::encoding::group::merge_repeated(tag, wire_type, #ident, buf, ctx) + }, + } + } + + pub fn encoded_len(&self, ident: TokenStream) -> TokenStream { + let tag = self.tag; + match self.label { + Label::Optional => quote! { + #ident.as_ref().map_or(0, |msg| ::prost::encoding::group::encoded_len(#tag, msg)) + }, + Label::Required => quote! { + ::prost::encoding::group::encoded_len(#tag, &#ident) + }, + Label::Repeated => quote! { + ::prost::encoding::group::encoded_len_repeated(#tag, &#ident) + }, + } + } + + pub fn clear(&self, ident: TokenStream) -> TokenStream { + match self.label { + Label::Optional => quote!(#ident = ::core::option::Option::None), + Label::Required => quote!(#ident.clear()), + Label::Repeated => quote!(#ident.clear()), + } + } +} |