refactoring

src/test/groovy/io/emeraldpay/dshackle/config/YamlConfigReaderSpec.groovy

@@ -15,6 +15,7 @@
  */
 package io.emeraldpay.dshackle.config
 
+import org.jetbrains.annotations.Nullable
 import org.yaml.snakeyaml.Yaml
 import org.yaml.snakeyaml.nodes.MappingNode
 import spock.lang.Specification
@@ -41,5 +42,10 @@ class YamlConfigReaderSpec extends Specification {
         return new Yaml().compose(new StringReader("$key: $value")) as MappingNode
     }
 
-    class Impl extends YamlConfigReader {}
+    class Impl extends YamlConfigReader {
+        @Override
+        Object read(@Nullable MappingNode input) {
+            return null
+        }
+    }
 }

src/test/resources/configs/chains-basic.yaml

@@ -1,7 +1,12 @@
 version: v1
 
-chains:
-  - name: eth
-    syncing-size: 10
-    lagging-size: 5
-
+chain-settings:
+  default:
+    lags:
+      syncing: 6
+      lagging: 1
+  chains:
+    - id: eth
+      lags:
+        syncing: 6
+        lagging: 1