Does this seem to be a bug from deserializing enum?

[MillerVictor]

serde version info

└── serde_derive v1.0.219 (proc-macro)
    ├── proc-macro2 v1.0.95
    │   └── unicode-ident v1.0.18
    ├── quote v1.0.40
    │   └── proc-macro2 v1.0.95 (*)
    └── syn v2.0.104
        ├── proc-macro2 v1.0.95 (*)
        ├── quote v1.0.40 (*)
        └── unicode-ident v1.0.18

serde v1.0.219
└── serde_derive v1.0.219 (proc-macro) (*)

serde_json v1.0.141
├── itoa v1.0.15
├── memchr v2.7.5
├── ryu v1.0.20
└── serde v1.0.219
    └── serde_derive v1.0.219 (proc-macro)

system info

stable-x86_64-pc-windows-msvc (active, default)
rustc 1.88.0 (6b00bc388 2025-06-23)

same rust code example

#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
pub struct Vote {
    vote_address: String,
    vote_count:u64,
}

pub type Votes = Vec<Vote>;


#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
#[serde(untagged)]
pub enum Case {
    VoteWitnessContract {
        owner_address: String,
      
        votes: Votes,
    },
    FreezeBalanceV2Contract{
        frozen_balance:i128,
        owner_address:String,
    }
}


#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
pub struct Content{
    data:Vec<Case>
}

#[test]
fn test_case(){
    let response =  r#"{"data":[{"owner_address":"41cf418b1cd1a610e8b370abc1e428848f82e3a153","votes":[{"vote_address":"4136b8367bdad6b910a86e1d8af121c870d9e12a71","vote_count":900}]},{"frozen_balance":500000000,"owner_address":"41cf418b1cd1a610e8b370abc1e428848f82e3a153"}]}"#;
    serde_json::from_str::<Content>(&response).unwrap();

}

Error info

---- case::test_case stdout ----
thread 'case::test_case' panicked at src\case.rs:33:48:
called `Result::unwrap()` on an `Err` value: Error("data did not match any variant of untagged enum Case", line: 1, column: 251)

Enum Excerpted from official examples #[serde(untagged)]

[Mingun]

i128 cannot be bufferized, and any features that depends on buffering (untagged and internally tagged enums, flattening), does not work. See #2781

[MillerVictor]

Provide the ability to perform additional operations for # [serde (tag="type")]

Consider the following code

#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
pub struct Vote {
    vote_address: String,
    vote_count: u64,
}

pub type Votes = Vec<Vote>;

#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
pub struct VoteWitnessContractValue {
    owner_address: String,
    votes: Votes,
}

#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
pub struct FreezeBalanceV2ContractValue {
    frozen_balance: i64,
    owner_address: String,
}
#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
#[serde(tag = "type")]
pub enum Row {
    VoteWitnessContract {
        value:VoteWitnessContractValue
    },
    FreezeBalanceV2Contract {
        value:FreezeBalanceV2ContractValue
    },
}




#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
pub struct Content {
    data: Vec<Row>,
}

#[test]
fn test_case_bad() {
    let response = r#"{"data":[{"value":{"owner_address":"41cf418b1cd1a610e8b370abc1e428848f82e3a153","votes":[{"vote_address":"4136b8367bdad6b910a86e1d8af121c870d9e12a71","vote_count":900}]},"type":"type.googleapis.com/protocol.VoteWitnessContract"},{"value":{"frozen_balance":500000000,"owner_address":"41cf418b1cd1a610e8b370abc1e428848f82e3a153"},"type":"type.googleapis.com/protocol.FreezeBalanceV2Contract"}]}"#;
    let content = serde_json::from_str::<Content>(&response).unwrap();

    println!("{:?}", content);
}

#[test]
fn test_case_good() {
    let response = r#"
{"data":[{"value":{"owner_address":"41cf418b1cd1a610e8b370abc1e428848f82e3a153","votes":[{"vote_address":"4136b8367bdad6b910a86e1d8af121c870d9e12a71","vote_count":900}]},"type":"VoteWitnessContract"},{"value":{"frozen_balance":500000000,"owner_address":"41cf418b1cd1a610e8b370abc1e428848f82e3a153"},"type":"FreezeBalanceV2Contract"}]}"#;
    let content = serde_json::from_str::<Content>(&response).unwrap();

    println!("{:?}", content);
}

explain

In other languages, this type may contain special characters, but in rust they are illegal in Enum. In this case, we need to perform some additional processing on the type field to return it properly. Perhaps#[serde (untagged)]can do the job, but specifying the type of#[serde (tag="type")]would be better

[Mingun]

In your case you may add #[serde(rename = "...")] on enum variants:

#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
#[serde(tag = "type")]
pub enum Row {
    #[serde(rename = "type.googleapis.com/protocol.VoteWitnessContract")]
    VoteWitnessContract {
        value:VoteWitnessContractValue
    },
    #[serde(rename = "type.googleapis.com/protocol.FreezeBalanceV2Contract")]
    FreezeBalanceV2Contract {
        value:FreezeBalanceV2ContractValue
    },
}

or use serde-prefix-all crate, which will allow you to add prefix to all variants.