fixup! Break ties of PreferDistinct submissions with equal counts

hello serde

Author: jerbaroo

Cargo.lock

@@ -28,7 +28,7 @@ ciborium = { version = "0.2.2", features = ["std"] }
 clap = { version = "4.5.60", features = ["derive", "std"] }
 criterion = { version = "0.8", features = ["async_tokio"] }
 crossbeam-skiplist = { version = "0.1.3", features = ["std"] }
-dashmap = { version = "6.1.0" }
+dashmap = { version = "6.1.0", features = ["serde"] }
 either = { version = "1.13.0" }
 futures = { version = "0.3.32" }
 http = { version = "1.4.0" }

Cargo.toml

@@ -109,16 +109,7 @@ impl MetaStateField {
     /// in a single FFI call.
     #[must_use]
     pub fn to_json(&self) -> String {
-        use std::fmt::Write as _;
-        let mut out = String::from("{");
-        for entry in &self.vals_to_counts {
-            if out.len() > 1 {
-                out.push(',');
-            }
-            let _ = write!(out, "\"{}\":{}", entry.key(), entry.value());
-        }
-        out.push('}');
-        out
+        serde_json::to_string(&self.vals_to_counts).unwrap_or_else(|_| String::from("{}"))
     }
 }