Group optional dependencies in Cargo.toml

Author: nicoburns

Cargo.toml

@@ -14,19 +14,21 @@ rust-version = "1.68"
 
 exclude = ["src/css-parsing-tests/**", "src/big-data-url.css"]
 
-[dev-dependencies]
-serde_json = "1.0.25"
-difference = "2.0"
-encoding_rs = "0.8"
-
 [dependencies]
-cssparser-macros = { path = "./macros", version = "0.6.1", optional = true }
 dtoa-short = "0.3"
 itoa = "1.0"
+smallvec = "1.0"
+
+# Optional dependencies
+cssparser-macros = { path = "./macros", version = "0.6.1", optional = true }
+malloc_size_of = { version = "0.1", default-features = false, optional = true }
 phf = { version = "0.13.1", features = ["macros"], optional = true }
 serde = { version = "1.0", features = ["derive"], optional = true }
-malloc_size_of = { version = "0.1", default-features = false, optional = true }
-smallvec = "1.0"
+
+[dev-dependencies]
+serde_json = "1.0.25"
+difference = "2.0"
+encoding_rs = "0.8"
 
 [profile.profiling]
 inherits = "release"