Upgrade to latest serde_yaml

This fixes serialization order to match declaration order (which is
good), so we need to update some serialization test cases.

Cargo.toml

@@ -26,9 +26,7 @@ log = "0.3.6"
 regex = "0.1.73"
 serde = "0.8"
 serde_derive = { version = "0.8", optional = true }
-# See https://github.com/dtolnay/serde-yaml/issues/30 before upgrading to
-# serde_yaml 0.5.x.
-serde_yaml = "0.4.1"
+serde_yaml = "0.5.0"
 yaml-rust = "0.3.3"
 url = "1.2.0"
 void = "1.0.2"

src/v2/build.in.rs

@@ -88,10 +88,10 @@ fn build_has_a_string_representation() {
 #[test]
 fn build_may_be_a_struct() {
     let yaml = r#"---
-"args":
-  "key": "value"
 "context": "."
 "dockerfile": "Dockerfile"
+"args":
+  "key": "value"
 "#;
     assert_roundtrip!(Build, yaml);
 

src/v2/extends.in.rs

@@ -47,8 +47,8 @@ impl Extends {
 #[test]
 fn extends_can_be_roundtripped() {
     let yaml = r#"---
-"file": "bar/docker-compose.yml"
 "service": "foo"
+"file": "bar/docker-compose.yml"
 "#;
     assert_roundtrip!(Extends, yaml);
 }

src/v2/file.in.rs

@@ -107,10 +107,10 @@ impl FromStr for File {
 #[cfg_attr(feature="clippy", allow(blacklisted_name))]
 fn file_can_be_converted_from_and_to_yaml() {
     let yaml = r#"---
+"version": "2"
 "services":
   "foo":
     "build": "."
-"version": "2"
 "volumes":
   "db":
     "external": true
@@ -125,10 +125,10 @@ fn file_can_be_converted_from_and_to_yaml() {
 #[test]
 fn file_can_only_load_from_version_2() {
     let yaml = r#"---
+"version": "3"
 "services":
   "foo":
     "build": "."
-"version": "3"
 "#;
     assert!(serde_yaml::from_str::<File>(&yaml).is_err());
 }