Remove `anyhow::Result` for lock serialization (#10151)

Cargo.lock

@@ -4454,6 +4454,7 @@ dependencies = [
  "thiserror 2.0.9",
  "tokio",
  "toml",
+ "toml_edit",
  "tracing",
  "tracing-durations-export",
  "tracing-subscriber",

crates/uv-resolver/src/lock/mod.rs

@@ -11,6 +11,7 @@ use itertools::Itertools;
 use petgraph::graph::NodeIndex;
 use petgraph::visit::EdgeRef;
 use rustc_hash::{FxHashMap, FxHashSet};
+use serde::Serializer;
 use toml_edit::{value, Array, ArrayOfTables, InlineTable, Item, Table, Value};
 use url::Url;
 
@@ -617,7 +618,7 @@ impl Lock {
     }
 
     /// Returns the TOML representation of this lockfile.
-    pub fn to_toml(&self) -> anyhow::Result<String> {
+    pub fn to_toml(&self) -> Result<String, toml_edit::ser::Error> {
         // We construct a TOML document manually instead of going through Serde to enable
         // the use of inline tables.
         let mut doc = toml_edit::DocumentMut::new();
@@ -2085,7 +2086,7 @@ impl Package {
         &self,
         requires_python: &RequiresPython,
         dist_count_by_name: &FxHashMap<PackageName, u64>,
-    ) -> anyhow::Result<Table> {
+    ) -> Result<Table, toml_edit::ser::Error> {
         let mut table = Table::new();
 
         self.id.to_toml(None, &mut table);
@@ -2149,7 +2150,7 @@ impl Package {
                 self.wheels
                     .iter()
                     .map(Wheel::to_toml)
-                    .collect::<anyhow::Result<Vec<_>>>()?
+                    .collect::<Result<Vec<_>, _>>()?
                     .into_iter(),
             );
             table.insert("wheels", value(wheels));
@@ -3224,7 +3225,7 @@ enum SourceDistWire {
 
 impl SourceDist {
     /// Returns the TOML representation of this source distribution.
-    fn to_toml(&self) -> anyhow::Result<InlineTable> {
+    fn to_toml(&self) -> Result<InlineTable, toml_edit::ser::Error> {
         let mut table = InlineTable::new();
         match &self {
             SourceDist::Metadata { .. } => {}
@@ -3239,7 +3240,10 @@ impl SourceDist {
             table.insert("hash", Value::from(hash.to_string()));
         }
         if let Some(size) = self.size() {
-            table.insert("size", Value::from(i64::try_from(size)?));
+            table.insert(
+                "size",
+                toml_edit::ser::ValueSerializer::new().serialize_u64(size)?,
+            );
         }
         Ok(table)
     }
@@ -3612,7 +3616,7 @@ enum WheelWireSource {
 
 impl Wheel {
     /// Returns the TOML representation of this wheel.
-    fn to_toml(&self) -> anyhow::Result<InlineTable> {
+    fn to_toml(&self) -> Result<InlineTable, toml_edit::ser::Error> {
         let mut table = InlineTable::new();
         match &self.url {
             WheelWireSource::Url { url } => {
@@ -3629,7 +3633,10 @@ impl Wheel {
             table.insert("hash", Value::from(hash.to_string()));
         }
         if let Some(size) = self.size {
-            table.insert("size", Value::from(i64::try_from(size)?));
+            table.insert(
+                "size",
+                toml_edit::ser::ValueSerializer::new().serialize_u64(size)?,
+            );
         }
         Ok(table)
     }

crates/uv/Cargo.toml

@@ -88,6 +88,7 @@ textwrap = { workspace = true }
 thiserror = { workspace = true }
 tokio = { workspace = true }
 toml = { workspace = true }
+toml_edit = { workspace = true }
 tracing = { workspace = true }
 tracing-durations-export = { workspace = true, features = ["plot"], optional = true }
 tracing-subscriber = { workspace = true, features = ["json"] }

crates/uv/src/commands/project/mod.rs

@@ -78,6 +78,9 @@ pub(crate) enum ProjectError {
     #[error("Failed to parse `uv.lock`, which uses an unsupported schema version (v{1}, but only v{0} is supported). Downgrade to a compatible uv version, or remove the `uv.lock` prior to running `uv lock` or `uv sync`.")]
     UnparsableLockVersion(u32, u32, #[source] toml::de::Error),
 
+    #[error("Failed to serialize `uv.lock`")]
+    LockSerialization(#[from] toml_edit::ser::Error),
+
     #[error("The current Python version ({0}) is not compatible with the locked Python requirement: `{1}`")]
     LockedPythonIncompatibility(Version, RequiresPython),