Merge pull request #1382 from roblabla/serde-other

Implement #[serde(other)] on enum variant
This commit is contained in:
David Tolnay 2018-09-11 22:59:30 -07:00 committed by GitHub
commit 2753ec757b
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4 changed files with 62 additions and 35 deletions

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@ -1157,6 +1157,10 @@ fn deserialize_externally_tagged_enum(
.map(|(i, variant)| (variant.attrs.name().deserialize_name(), field_i(i)))
.collect();
let other_idx = variants
.iter()
.position(|ref variant| variant.attrs.other());
let variants_stmt = {
let variant_names = variant_names_idents.iter().map(|&(ref name, _)| name);
quote! {
@ -1168,6 +1172,7 @@ fn deserialize_externally_tagged_enum(
&variant_names_idents,
cattrs,
true,
other_idx
));
// Match arms to extract a variant from a string
@ -1255,6 +1260,10 @@ fn deserialize_internally_tagged_enum(
.map(|(i, variant)| (variant.attrs.name().deserialize_name(), field_i(i)))
.collect();
let other_idx = variants
.iter()
.position(|ref variant| variant.attrs.other());
let variants_stmt = {
let variant_names = variant_names_idents.iter().map(|&(ref name, _)| name);
quote! {
@ -1266,6 +1275,7 @@ fn deserialize_internally_tagged_enum(
&variant_names_idents,
cattrs,
true,
other_idx
));
// Match arms to extract a variant from a string
@ -1324,6 +1334,10 @@ fn deserialize_adjacently_tagged_enum(
.map(|(i, variant)| (variant.attrs.name().deserialize_name(), field_i(i)))
.collect();
let other_idx = variants
.iter()
.position(|ref variant| variant.attrs.other());
let variants_stmt = {
let variant_names = variant_names_idents.iter().map(|&(ref name, _)| name);
quote! {
@ -1335,6 +1349,7 @@ fn deserialize_adjacently_tagged_enum(
&variant_names_idents,
cattrs,
true,
other_idx
));
let variant_arms: &Vec<_> = &variants
@ -1842,6 +1857,7 @@ fn deserialize_generated_identifier(
fields: &[(String, Ident)],
cattrs: &attr::Container,
is_variant: bool,
other_idx: Option<usize>
) -> Fragment {
let this = quote!(__Field);
let field_idents: &Vec<_> = &fields.iter().map(|&(_, ref ident)| ident).collect();
@ -1850,6 +1866,10 @@ fn deserialize_generated_identifier(
let ignore_variant = quote!(__other(_serde::private::de::Content<'de>),);
let fallthrough = quote!(_serde::export::Ok(__Field::__other(__value)));
(Some(ignore_variant), Some(fallthrough))
} else if let Some(other_idx) = other_idx {
let ignore_variant = fields[other_idx].1.clone();
let fallthrough = quote!(_serde::export::Ok(__Field::#ignore_variant));
(None, Some(fallthrough))
} else if is_variant || cattrs.deny_unknown_fields() {
(None, None)
} else {
@ -2272,7 +2292,7 @@ fn deserialize_struct_as_struct_visitor(
}
};
let field_visitor = deserialize_generated_identifier(&field_names_idents, cattrs, false);
let field_visitor = deserialize_generated_identifier(&field_names_idents, cattrs, false, None);
let visit_map = deserialize_map(struct_path, params, fields, cattrs);
@ -2292,7 +2312,7 @@ fn deserialize_struct_as_map_visitor(
.map(|(i, field)| (field.attrs.name().deserialize_name(), field_i(i)))
.collect();
let field_visitor = deserialize_generated_identifier(&field_names_idents, cattrs, false);
let field_visitor = deserialize_generated_identifier(&field_names_idents, cattrs, false, None);
let visit_map = deserialize_map(struct_path, params, fields, cattrs);
@ -2527,7 +2547,7 @@ fn deserialize_struct_as_struct_in_place_visitor(
}
};
let field_visitor = deserialize_generated_identifier(&field_names_idents, cattrs, false);
let field_visitor = deserialize_generated_identifier(&field_names_idents, cattrs, false, None);
let visit_map = deserialize_map_in_place(params, fields, cattrs);

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@ -93,7 +93,7 @@ fn check_flatten_field(cx: &Ctxt, style: Style, field: &Field) {
}
/// The `other` attribute must be used at most once and it must be the last
/// variant of an enum that has the `field_identifier` attribute.
/// 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
@ -111,42 +111,48 @@ fn check_identifier(cx: &Ctxt, cont: &Container) {
variant.style,
cont.attrs.identifier(),
variant.attrs.other(),
cont.attrs.tag()
) {
// The `other` attribute may only be used in a field_identifier.
(_, Identifier::Variant, true) | (_, Identifier::No, true) => {
cx.error("#[serde(other)] may only be used inside a field_identifier");
// The `other` attribute may not be used in a variant_identifier.
(_, Identifier::Variant, true, _) => {
cx.error("#[serde(other)] may not be used on a variant_identifier");
},
// Variant with `other` attribute cannot appear in untagged enum
(_, Identifier::No, true, &EnumTag::None) => {
cx.error("#[serde(other)] cannot appear on untagged enum");
}
// Variant with `other` attribute must be the last one.
(Style::Unit, Identifier::Field, true) => {
(Style::Unit, Identifier::Field, true, _) | (Style::Unit, Identifier::No, true, _) => {
if i < variants.len() - 1 {
cx.error("#[serde(other)] must be the last variant");
}
}
// Variant with `other` attribute must be a unit variant.
(_, Identifier::Field, true) => {
(_, Identifier::Field, true, _) | (_, Identifier::No, true, _) => {
cx.error("#[serde(other)] must be on a unit variant");
}
},
// Any sort of variant is allowed if this is not an identifier.
(_, Identifier::No, false) => {}
(_, Identifier::No, false, _) => {}
// Unit variant without `other` attribute is always fine.
(Style::Unit, _, false) => {}
(Style::Unit, _, false, _) => {}
// The last field is allowed to be a newtype catch-all.
(Style::Newtype, Identifier::Field, false) => {
(Style::Newtype, Identifier::Field, false, _) => {
if i < variants.len() - 1 {
cx.error(format!("`{}` must be the last variant", variant.ident));
}
}
(_, Identifier::Field, false) => {
(_, Identifier::Field, false, _) => {
cx.error("field_identifier may only contain unit variants");
}
(_, Identifier::Variant, false) => {
(_, Identifier::Variant, false, _) => {
cx.error("variant_identifier may only contain unit variants");
}
}

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@ -1,20 +0,0 @@
// Copyright 2017 Serde Developers
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
#[macro_use]
extern crate serde_derive;
#[derive(Deserialize)]
enum F {
A,
#[serde(other)]
//~^^^^ ERROR: #[serde(other)] may only be used inside a field_identifier
B,
}
fn main() {}

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@ -135,6 +135,13 @@ enum EnumSkipAll {
Skipped,
}
#[derive(PartialEq, Debug, Deserialize)]
enum EnumOther {
Unit,
#[serde(other)]
Other
}
//////////////////////////////////////////////////////////////////////////
macro_rules! declare_tests {
@ -753,6 +760,20 @@ declare_tests! {
Token::Unit,
],
}
test_enum_other_unit {
EnumOther::Unit => &[
Token::Enum { name: "EnumOther" },
Token::Str("Unit"),
Token::Unit,
],
}
test_enum_other {
EnumOther::Other => &[
Token::Enum { name: "EnumOther" },
Token::Str("Foo"),
Token::Unit,
],
}
test_box {
Box::new(0i32) => &[Token::I32(0)],
}