perf: Speed up TOML parsing by upgrading toml (#15736)

### What does this PR try to resolve?

For numbers, see https://epage.github.io/blog/2025/07/toml-09/

Further areas for improvement:
- Enable `fast_hash` (see #15649)
- Only track spans for local manifests, allowing us to skip the
`make_owned` call for most packages

### How to test and review this PR?

Author: weihanglo

Cargo.lock

@@ -105,8 +105,8 @@ tar = { version = "0.4.44", default-features = false }
 tempfile = "3.20.0"
 thiserror = "2.0.12"
 time = { version = "0.3.41", features = ["parsing", "formatting", "serde"] }
-toml = { version = "0.8.23", default-features = false }
-toml_edit = { version = "0.22.27", features = ["serde"] }
+toml = { version = "0.9.0", default-features = false }
+toml_edit = { version = "0.23.0", features = ["serde"] }
 tracing = { version = "0.1.41", default-features = false, features = ["std"] } # be compatible with rustc_log: https://github.com/rust-lang/rust/blob/e51e98dde6a/compiler/rustc_log/Cargo.toml#L9
 tracing-chrome = "0.7.2"
 tracing-subscriber = { version = "0.3.19", features = ["env-filter"] }
@@ -211,7 +211,7 @@ tar.workspace = true
 tempfile.workspace = true
 thiserror.workspace = true
 time.workspace = true
-toml = { workspace = true, features = ["display", "parse"] }
+toml = { workspace = true, features = ["std", "serde", "parse", "display", "preserve_order"] }
 toml_edit.workspace = true
 tracing = { workspace = true, features = ["attributes"] }
 tracing-subscriber.workspace = true

Cargo.toml

@@ -10,7 +10,7 @@ publish = false
 cargo_metadata.workspace = true
 flate2.workspace = true
 tar.workspace = true
-toml = { workspace = true, features = ["display", "parse"] }
+toml = { workspace = true, features = ["display", "parse", "serde"] }
 
 [lints]
 workspace = true

benches/capture/Cargo.toml

@@ -27,7 +27,7 @@ serde_json.workspace = true
 snapbox.workspace = true
 tar.workspace = true
 time.workspace = true
-toml = { workspace = true, features = ["display"] }
+toml = { workspace = true, features = ["display", "serde"] }
 url.workspace = true
 walkdir.workspace = true
 

crates/cargo-test-support/Cargo.toml

@@ -16,7 +16,7 @@ serde_json = { workspace = true, optional = true }
 serde-untagged.workspace = true
 serde-value.workspace = true
 thiserror.workspace = true
-toml.workspace = true
+toml = { workspace = true, features = ["serde"] }
 unicode-xid.workspace = true
 url.workspace = true
 

crates/cargo-util-schemas/Cargo.toml

@@ -63,7 +63,7 @@ impl EitherManifest {
 pub struct Manifest {
     // alternate forms of manifests:
     contents: Rc<String>,
-    document: Rc<toml_edit::ImDocument<String>>,
+    document: Rc<toml::Spanned<toml::de::DeTable<'static>>>,
     original_toml: Rc<TomlManifest>,
     normalized_toml: Rc<TomlManifest>,
     summary: Summary,
@@ -109,7 +109,7 @@ pub struct Warnings(Vec<DelayedWarning>);
 pub struct VirtualManifest {
     // alternate forms of manifests:
     contents: Rc<String>,
-    document: Rc<toml_edit::ImDocument<String>>,
+    document: Rc<toml::Spanned<toml::de::DeTable<'static>>>,
     original_toml: Rc<TomlManifest>,
     normalized_toml: Rc<TomlManifest>,
 
@@ -496,7 +496,7 @@ compact_debug! {
 impl Manifest {
     pub fn new(
         contents: Rc<String>,
-        document: Rc<toml_edit::ImDocument<String>>,
+        document: Rc<toml::Spanned<toml::de::DeTable<'static>>>,
         original_toml: Rc<TomlManifest>,
         normalized_toml: Rc<TomlManifest>,
         summary: Summary,
@@ -565,7 +565,7 @@ impl Manifest {
         Ok(format!("{}\n{}", MANIFEST_PREAMBLE, toml))
     }
     /// Collection of spans for the original TOML
-    pub fn document(&self) -> &toml_edit::ImDocument<String> {
+    pub fn document(&self) -> &toml::Spanned<toml::de::DeTable<'static>> {
         &self.document
     }
     /// The [`TomlManifest`] as parsed from [`Manifest::document`]
@@ -738,7 +738,7 @@ impl Manifest {
 impl VirtualManifest {
     pub fn new(
         contents: Rc<String>,
-        document: Rc<toml_edit::ImDocument<String>>,
+        document: Rc<toml::Spanned<toml::de::DeTable<'static>>>,
         original_toml: Rc<TomlManifest>,
         normalized_toml: Rc<TomlManifest>,
         replace: Vec<(PackageIdSpec, Dependency)>,
@@ -766,7 +766,7 @@ impl VirtualManifest {
         self.contents.as_str()
     }
     /// Collection of spans for the original TOML
-    pub fn document(&self) -> &toml_edit::ImDocument<String> {
+    pub fn document(&self) -> &toml::Spanned<toml::de::DeTable<'static>> {
         &self.document
     }
     /// The [`TomlManifest`] as parsed from [`VirtualManifest::document`]

src/cargo/core/manifest.rs

@@ -1043,10 +1043,9 @@ impl GlobalContext {
         let def = Definition::Environment(key.as_env_key().to_string());
         if self.cli_unstable().advanced_env && env_val.starts_with('[') && env_val.ends_with(']') {
             // Parse an environment string as a TOML array.
-            let toml_v = toml::Value::deserialize(toml::de::ValueDeserializer::new(&env_val))
-                .map_err(|e| {
-                    ConfigError::new(format!("could not parse TOML list: {}", e), def.clone())
-                })?;
+            let toml_v = env_val.parse::<toml::Value>().map_err(|e| {
+                ConfigError::new(format!("could not parse TOML list: {}", e), def.clone())
+            })?;
             let values = toml_v.as_array().expect("env var was not array");
             for value in values {
                 // TODO: support other types.

src/cargo/util/context/mod.rs

@@ -6,7 +6,6 @@ use pathdiff::diff_paths;
 use std::fmt::Display;
 use std::ops::Range;
 use std::path::Path;
-use toml_edit::ImDocument;
 
 const LINT_GROUPS: &[LintGroup] = &[TEST_DUMMY_UNSTABLE];
 pub const LINTS: &[Lint] = &[IM_A_TEAPOT, UNKNOWN_LINTS];
@@ -16,7 +15,7 @@ pub fn analyze_cargo_lints_table(
     path: &Path,
     pkg_lints: &TomlToolLints,
     ws_contents: &str,
-    ws_document: &ImDocument<String>,
+    ws_document: &toml::Spanned<toml::de::DeTable<'static>>,
     ws_path: &Path,
     gctx: &GlobalContext,
 ) -> CargoResult<()> {
@@ -116,7 +115,7 @@ fn verify_feature_enabled(
     manifest: &Manifest,
     manifest_path: &str,
     ws_contents: &str,
-    ws_document: &ImDocument<String>,
+    ws_document: &toml::Spanned<toml::de::DeTable<'static>>,
     ws_path: &str,
     error_count: &mut usize,
     gctx: &GlobalContext,
@@ -191,43 +190,33 @@ fn verify_feature_enabled(
 }
 
 pub fn get_span(
-    document: &ImDocument<String>,
+    document: &toml::Spanned<toml::de::DeTable<'static>>,
     path: &[&str],
     get_value: bool,
 ) -> Option<Range<usize>> {
-    let mut table = document.as_item().as_table_like()?;
+    let mut table = document.get_ref();
     let mut iter = path.into_iter().peekable();
     while let Some(key) = iter.next() {
-        let (key, item) = table.get_key_value(key)?;
+        let key_s: &str = key.as_ref();
+        let (key, item) = table.get_key_value(key_s)?;
         if iter.peek().is_none() {
             return if get_value {
-                item.span()
+                Some(item.span())
             } else {
-                let leaf_decor = key.dotted_decor();
-                let leaf_prefix_span = leaf_decor.prefix().and_then(|p| p.span());
-                let leaf_suffix_span = leaf_decor.suffix().and_then(|s| s.span());
-                if let (Some(leaf_prefix_span), Some(leaf_suffix_span)) =
-                    (leaf_prefix_span, leaf_suffix_span)
-                {
-                    Some(leaf_prefix_span.start..leaf_suffix_span.end)
-                } else {
-                    key.span()
-                }
+                Some(key.span())
             };
         }
-        if item.is_table_like() {
-            table = item.as_table_like().unwrap();
+        if let Some(next_table) = item.get_ref().as_table() {
+            table = next_table;
         }
-        if item.is_array() && iter.peek().is_some() {
-            let array = item.as_array().unwrap();
-            let next = iter.next().unwrap();
-            return array.iter().find_map(|item| {
-                if next == &item.to_string() {
-                    item.span()
-                } else {
-                    None
-                }
-            });
+        if iter.peek().is_some() {
+            if let Some(array) = item.get_ref().as_array() {
+                let next = iter.next().unwrap();
+                return array.iter().find_map(|item| match item.get_ref() {
+                    toml::de::DeValue::String(s) if s == next => Some(item.span()),
+                    _ => None,
+                });
+            }
         }
     }
     None
@@ -511,7 +500,7 @@ fn output_unknown_lints(
     manifest_path: &str,
     pkg_lints: &TomlToolLints,
     ws_contents: &str,
-    ws_document: &ImDocument<String>,
+    ws_document: &toml::Spanned<toml::de::DeTable<'static>>,
     ws_path: &str,
     error_count: &mut usize,
     gctx: &GlobalContext,