fix: add equals and hashCode to SimpleResult (#11827) (#11841)

fixes #10948

Co-authored-by: Denis <[email protected]>

flow-data/src/main/java/com/vaadin/flow/data/binder/SimpleResult.java

@@ -110,4 +110,25 @@ public <X extends Throwable> R getOrThrow(
         }
     }
 
+    @Override
+    public boolean equals(Object obj) {
+        if (obj == this) {
+            return true;
+        }
+        if (obj == null) {
+            return false;
+        }
+        if (!obj.getClass().equals(getClass())) {
+            return false;
+        }
+        SimpleResult<?> that = (SimpleResult<?>) obj;
+        return Objects.equals(that.value, value)
+                && Objects.equals(that.message, message);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(value, message);
+    }
+
 }

flow-data/src/test/java/com/vaadin/flow/data/binder/SimpleResultTest.java

@@ -0,0 +1,64 @@
+/*
+ * Copyright 2000-2021 Vaadin Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy of
+ * the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package com.vaadin.flow.data.binder;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+public class SimpleResultTest {
+
+    @Test
+    public void twoEqualSimpleResults_objectsAreEqual() {
+        SimpleResult<String> one = new SimpleResult<String>("foo", null);
+        SimpleResult<String> two = new SimpleResult<String>("foo", null);
+        Assert.assertEquals(one, two);
+    }
+
+    @Test
+    public void differentValues_objectsAreUnequal() {
+        SimpleResult<String> one = new SimpleResult<String>("foo", null);
+        SimpleResult<String> two = new SimpleResult<String>("baz", null);
+        Assert.assertNotEquals(one, two);
+    }
+
+    @Test
+    public void differentMessages_objectsAreUnequal() {
+        SimpleResult<String> one = new SimpleResult<String>(null, "bar");
+        SimpleResult<String> two = new SimpleResult<String>(null, "baz");
+        Assert.assertNotEquals(one, two);
+    }
+
+    @Test
+    public void differentClasses_objectsAreUnequal() {
+        SimpleResult<String> one = new SimpleResult<String>("foo", null);
+        SimpleResult<String> two = new SimpleResult<String>("foo", null) {
+        };
+        Assert.assertNotEquals(one, two);
+    }
+
+    @Test
+    public void nullIsNotEqualToObject() {
+        SimpleResult<String> one = new SimpleResult<String>("foo", null);
+        Assert.assertNotEquals(one, null);
+    }
+
+    @Test
+    public void twoEqualSimpleResults_hashCodeIsTheSame() {
+        SimpleResult<String> one = new SimpleResult<String>("foo", null);
+        SimpleResult<String> two = new SimpleResult<String>("foo", null);
+        Assert.assertEquals(one.hashCode(), two.hashCode());
+    }
+}