adding failing test for repro of rust-cli#417 showcasing failure to parse key containing periods in yaml

Author: Halkcyon

tests/Settings.yaml

@@ -15,3 +15,4 @@ place:
 # For override tests
 FOO: FOO should be overridden
 bar: I am bar
+192.168.1.1: a string value

tests/file_yaml.rs

@@ -26,6 +26,8 @@ struct Settings {
     place: Place,
     #[serde(rename = "arr")]
     elements: Vec<String>,
+    #[serde(rename = "192.168.1.1")]
+    ip_key: String,
 }
 
 fn make() -> Config {
@@ -35,6 +37,15 @@ fn make() -> Config {
         .unwrap()
 }
 
+#[test]
+fn test_keys_with_periods_deserialize() {
+    let c = make();
+
+    let s: Settings = c.try_deserialize().unwrap();
+
+    assert_eq!(s.ip_key, "a string value");
+}
+
 #[test]
 fn test_file() {
     let c = make();