fix: make prop def getter backward-compatible

Return early for non-nested properties as before,
and undefined instead of erroring out when the
property type is undefined.

lib/connector.js

@@ -155,20 +155,24 @@ Connector.getNestedPropertyDefinition = function(definition, propPath) {
   const isArray = !isPropUndefined && Array.isArray(prop.type);
   const isFunction = !isPropUndefined && !isArray && typeof prop.type === 'function';
 
+  if (propPath.length === 1) return prop;
+
   if (isPropUndefined || (propPath.length > 1 && (isArray && prop.type.length === 0))) {
-    throw new Error(g.f('Invalid property path'));
+    return undefined;
   }
 
-  if (propPath.length === 1) return prop;
-
   const nextDefinition =
     (isArray && prop.type[0].definition) ||
     (isFunction && prop.type.definition);
 
-  return Connector.getNestedPropertyDefinition(
-    nextDefinition,
-    propPath.slice(1)
-  );
+  if (nextDefinition === undefined) {
+    return undefined;
+  } else {
+    return Connector.getNestedPropertyDefinition(
+      nextDefinition,
+      propPath.slice(1)
+    );
+  }
 };
 
 /**

test/connector.test.js

@@ -96,12 +96,17 @@ describe('Connector', () => {
       expect(propDefinition.type).to.equal(Date);
     });
 
-    it('should fail for non-existing properties', () => {
-      expect(() =>
-        connector.getPropertyDefinition(
-          'MyModel',
-          'non.existing.property'
-        )).to.throw(/Invalid property path/);
+    it('should return undefined for non-existing properties', () => {
+      const definition = connector.getPropertyDefinition('MyModel',
+        'non.existing.property');
+      // eslint-disable-next-line no-unused-expressions
+      expect(definition).to.be.undefined;
+    });
+
+    it('should preserve backward-compatibility for non-existing property', () => {
+      const definition = connector.getPropertyDefinition('MyModel', 'idontexist');
+      // eslint-disable-next-line no-unused-expressions
+      expect(definition).to.be.undefined;
     });
   });
 });