duplicated field names in records are invalid

Author: creativcoder

src/error.rs

@@ -113,6 +113,8 @@ pub enum AvrowErr {
     ParsingCanonicalForm,
     #[error("Duplicate definition of named schema")]
     DuplicateSchema,
+    #[error("Duplicate field name in record schema")]
+    DuplicateField,
     #[error("Invalid default value for union. Must be the first entry from union definition")]
     FailedDefaultUnion,
     #[error("Invalid default value for given schema")]

src/schema/parser.rs

@@ -152,6 +152,10 @@ impl Registry {
 
                     let aliases = parse_aliases(o.get("aliases"));
 
+                    if fields_parsed.contains_key(name) {
+                        return Err(AvrowErr::DuplicateField);
+                    }
+
                     fields_parsed.insert(
                         name.to_string(),
                         Field::new(name, ty, default, order, aliases)?,

src/schema/tests.rs

@@ -435,3 +435,21 @@ fn test_two_instance_schema_equality() {
     let schema2 = Schema::from_str(raw_schema).unwrap();
     assert_eq!(schema, schema2);
 }
+
+#[test]
+#[should_panic(expected = "DuplicateField")]
+fn duplicate_field_name_in_record_fails() {
+    let raw_schema = r#"
+        {
+        "type": "record",
+        "name": "Person",
+        "doc": "Hi there.",
+        "fields": [
+            {"name": "id", "type": "string", "default": "dsf8e8"},
+            {"name": "id", "type": "int", "default": 56}
+        ]
+        }
+    "#;
+
+    Schema::from_str(raw_schema).unwrap();
+}