Merge pull request #771 from elliottslaughter:internally_content_tagged

This commit is contained in:
David Tolnay
2017-02-19 16:08:18 -08:00
4 changed files with 247 additions and 18 deletions
+44 -7
View File
@@ -110,7 +110,14 @@ pub enum EnumTag {
/// ```json
/// {"type": "variant1", "key1": "value1", "key2": "value2"}
/// ```
Internal(String),
Internal { tag: String },
/// `#[serde(tag = "t", content = "c")]`
///
/// ```json
/// {"t": "variant1", "c": {"key1": "value1", "key2": "value2"}}
/// ```
Adjacent { tag: String, content: String },
/// `#[serde(untagged)]`
///
@@ -130,6 +137,7 @@ impl Item {
let mut de_bound = Attr::none(cx, "bound");
let mut untagged = BoolAttr::none(cx, "untagged");
let mut internal_tag = Attr::none(cx, "tag");
let mut content = Attr::none(cx, "content");
for meta_items in item.attrs.iter().filter_map(get_serde_meta_items) {
for meta_item in meta_items {
@@ -198,6 +206,20 @@ impl Item {
}
}
// Parse `#[serde(content = "c")]`
MetaItem(NameValue(ref name, ref lit)) if name == "content" => {
if let Ok(s) = get_string_from_lit(cx, name.as_ref(), name.as_ref(), lit) {
match item.body {
syn::Body::Enum(_) => {
content.set(s);
}
syn::Body::Struct(_) => {
cx.error("#[serde(content = \"...\")] can only be used on enums")
}
}
}
}
MetaItem(ref meta_item) => {
cx.error(format!("unknown serde container attribute `{}`",
meta_item.name()));
@@ -210,10 +232,10 @@ impl Item {
}
}
let tag = match (untagged.get(), internal_tag.get()) {
(false, None) => EnumTag::External,
(true, None) => EnumTag::None,
(false, Some(tag)) => {
let tag = match (untagged.get(), internal_tag.get(), content.get()) {
(false, None, None) => EnumTag::External,
(true, None, None) => EnumTag::None,
(false, Some(tag), None) => {
// Check that there are no tuple variants.
if let syn::Body::Enum(ref variants) = item.body {
for variant in variants {
@@ -230,12 +252,27 @@ impl Item {
}
}
}
EnumTag::Internal(tag)
EnumTag::Internal { tag: tag }
}
(true, Some(_)) => {
(true, Some(_), None) => {
cx.error("enum cannot be both untagged and internally tagged");
EnumTag::External // doesn't matter, will error
}
(false, None, Some(_)) => {
cx.error("#[serde(tag = \"...\", content = \"...\")] must be used together");
EnumTag::External
}
(true, None, Some(_)) => {
cx.error("untagged enum cannot have #[serde(content = \"...\")]");
EnumTag::External
}
(false, Some(tag), Some(content)) => {
EnumTag::Adjacent { tag: tag, content: content }
}
(true, Some(_), Some(_)) => {
cx.error("untagged enum cannot have #[serde(tag = \"...\", content = \"...\")]");
EnumTag::External
}
};
Item {