improve error messages

Author: nicoburniske

src/main.rs

@@ -78,7 +78,8 @@ fn main() {
 fn parse_openapi_specs(spec: &Vec<PathBuf>) -> Vec<OpenAPI> {
     spec.into_iter()
         .map(|spec| {
-            let file = File::open(&spec).unwrap();
+            let file =
+                File::open(&spec).expect(format!("Could not open file: {:?}", spec).as_str());
             let reader = BufReader::new(file);
             let openapi: OpenAPI = serde_yaml::from_reader(reader)
                 .expect(format!("Could not deserialize input: {:?}", spec).as_str());

src/merger.rs

@@ -228,15 +228,17 @@ fn merge_unique<Key, Item>(
 ) -> Result<IndexMap<Key, Item>>
 where
     Key: std::fmt::Debug + Eq + std::hash::Hash,
-    Item: PartialEq,
+    Item: std::fmt::Debug + PartialEq,
 {
     for (key, value) in b {
         match a.entry(key) {
             indexmap::map::Entry::Occupied(entry) => {
                 if entry.get() != &value {
                     return Err(Error::unexpected(format!(
-                        "Duplicate key {:?} with different values",
-                        entry.key()
+                        "Duplicate key {:?} with different values \n Current {:?} \n New {:?}",
+                        entry.key(),
+                        entry.get(),
+                        value
                     )));
                 }
             }