Use toml_edit instead of toml (#7327)

# Objective
Fixes #5675. Replace `toml` with `toml_edit`

## Solution
Replace `toml` with `toml_edit`. This conveniently also removes the `serde` dependency from `bevy_macro_utils`, which may speed up cold compilation by removing the serde bottleneck from most of the macro crates in the engine.

crates/bevy_macro_utils/Cargo.toml

@@ -9,6 +9,6 @@ license = "MIT OR Apache-2.0"
 keywords = ["bevy"]
 
 [dependencies]
-toml = "0.5.8"
+toml_edit = "0.17"
 syn = "1.0"
 quote = "1.0"

crates/bevy_macro_utils/src/lib.rs

@@ -12,10 +12,10 @@ use proc_macro::TokenStream;
 use quote::{quote, quote_spanned};
 use std::{env, path::PathBuf};
 use syn::spanned::Spanned;
-use toml::{map::Map, Value};
+use toml_edit::{Document, Item};
 
 pub struct BevyManifest {
-    manifest: Map<String, Value>,
+    manifest: Document,
 }
 
 impl Default for BevyManifest {
@@ -26,7 +26,7 @@ impl Default for BevyManifest {
                 .map(|mut path| {
                     path.push("Cargo.toml");
                     let manifest = std::fs::read_to_string(path).unwrap();
-                    toml::from_str(&manifest).unwrap()
+                    manifest.parse::<Document>().unwrap()
                 })
                 .unwrap(),
         }
@@ -37,18 +37,15 @@ const BEVY_INTERNAL: &str = "bevy_internal";
 
 impl BevyManifest {
     pub fn maybe_get_path(&self, name: &str) -> Option<syn::Path> {
-        fn dep_package(dep: &Value) -> Option<&str> {
+        fn dep_package(dep: &Item) -> Option<&str> {
             if dep.as_str().is_some() {
                 None
             } else {
-                dep.as_table()
+                dep.get("package").map(|name| name.as_str().unwrap())
-                    .unwrap()
-                    .get("package")
-                    .map(|name| name.as_str().unwrap())
             }
         }
 
-        let find_in_deps = |deps: &Map<String, Value>| -> Option<syn::Path> {
+        let find_in_deps = |deps: &Item| -> Option<syn::Path> {
             let package = if let Some(dep) = deps.get(name) {
                 return Some(Self::parse_str(dep_package(dep).unwrap_or(name)));
             } else if let Some(dep) = deps.get(BEVY) {
@@ -66,14 +63,8 @@ impl BevyManifest {
             Some(path)
         };
 
-        let deps = self
+        let deps = self.manifest.get("dependencies");
-            .manifest
+        let deps_dev = self.manifest.get("dev-dependencies");
-            .get("dependencies")
-            .map(|deps| deps.as_table().unwrap());
-        let deps_dev = self
-            .manifest
-            .get("dev-dependencies")
-            .map(|deps| deps.as_table().unwrap());
 
         deps.and_then(find_in_deps)
             .or_else(|| deps_dev.and_then(find_in_deps))

tools/build-example-pages/Cargo.toml

@@ -7,7 +7,7 @@ publish = false
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-toml = "0.5"
+toml_edit = "0.17"
 tera = "1.15"
 serde = { version = "1.0", features = [ "derive" ] }
 bitflags = "1.3"

tools/build-example-pages/src/main.rs

@@ -3,7 +3,7 @@ use std::{cmp::Ordering, collections::HashMap, fs::File};
 use bitflags::bitflags;
 use serde::Serialize;
 use tera::{Context, Tera};
-use toml::Value;
+use toml_edit::Document;
 
 bitflags! {
     struct Command: u32 {
@@ -89,7 +89,7 @@ impl PartialOrd for Example {
 
 fn parse_examples(panic_on_missing: bool) -> Vec<Example> {
     let manifest_file = std::fs::read_to_string("Cargo.toml").unwrap();
-    let manifest: HashMap<String, Value> = toml::from_str(&manifest_file).unwrap();
+    let manifest = manifest_file.parse::<Document>().unwrap();
     let metadatas = manifest
         .get("package")
         .unwrap()
@@ -99,11 +99,11 @@ fn parse_examples(panic_on_missing: bool) -> Vec<Example> {
         .clone();
 
     manifest["example"]
-        .as_array()
+        .as_array_of_tables()
         .unwrap()
         .iter()
         .flat_map(|val| {
-            let technical_name = val["name"].as_str().unwrap().to_string();
+            let technical_name = val.get("name").unwrap().as_str().unwrap().to_string();
             if panic_on_missing && metadatas.get(&technical_name).is_none() {
                 panic!("Missing metadata for example {technical_name}");
             }
@@ -132,7 +132,7 @@ fn parse_examples(panic_on_missing: bool) -> Vec<Example> {
 
 fn parse_categories() -> HashMap<String, String> {
     let manifest_file = std::fs::read_to_string("Cargo.toml").unwrap();
-    let manifest: HashMap<String, Value> = toml::from_str(&manifest_file).unwrap();
+    let manifest = manifest_file.parse::<Document>().unwrap();
     manifest
         .get("package")
         .unwrap()
@@ -140,7 +140,7 @@ fn parse_categories() -> HashMap<String, String> {
         .as_ref()
         .unwrap()["category"]
         .clone()
-        .as_array()
+        .as_array_of_tables()
         .unwrap()
         .iter()
         .map(|v| {