From 135eb21cff384605969d4e773d03ff6a92d718fc Mon Sep 17 00:00:00 2001
From: Igor Melnichenko <i-melnichenko@yandex-team.ru>
Date: Wed, 5 Aug 2026 01:46:47 +0300
Subject: [PATCH] Include nested issues in Issue equality

equals and hashCode ignored the nested issues, so two issues that
differed only in their children compared equal.
---
 core/src/main/java/tech/ydb/core/Issue.java   |  5 +++-
 .../test/java/tech/ydb/core/IssueTest.java    | 28 ++++++++++++++++++-
 .../ydb/query/impl/QueryIntegrationTest.java  |  8 ++++--
 3 files changed, 37 insertions(+), 4 deletions(-)

diff --git a/core/src/main/java/tech/ydb/core/Issue.java b/core/src/main/java/tech/ydb/core/Issue.java
index ddf4c0b65..6ef63b325 100644
--- a/core/src/main/java/tech/ydb/core/Issue.java
+++ b/core/src/main/java/tech/ydb/core/Issue.java
@@ -1,6 +1,7 @@
 package tech.ydb.core;
 
 import java.io.Serializable;
+import java.util.Arrays;
 import java.util.List;
 import java.util.Objects;
 
@@ -146,7 +147,8 @@ public boolean equals(Object o) {
                 && Objects.equals(position, issue.position)
                 && Objects.equals(endPosition, issue.endPosition)
                 && Objects.equals(message, issue.message)
-                && severity == issue.severity;
+                && severity == issue.severity
+                && Arrays.equals(issues, issue.issues);
     }
 
     @Override
@@ -156,6 +158,7 @@ public int hashCode() {
         result = 31 * result + code;
         result = 31 * result + message.hashCode();
         result = 31 * result + severity.hashCode();
+        result = 31 * result + Arrays.hashCode(issues);
         return result;
     }
 
diff --git a/core/src/test/java/tech/ydb/core/IssueTest.java b/core/src/test/java/tech/ydb/core/IssueTest.java
index b47d62c44..64f9569bb 100644
--- a/core/src/test/java/tech/ydb/core/IssueTest.java
+++ b/core/src/test/java/tech/ydb/core/IssueTest.java
@@ -1,9 +1,10 @@
 package tech.ydb.core;
 
-import tech.ydb.core.Issue.Position;
 import org.junit.Assert;
 import org.junit.Test;
 
+import tech.ydb.core.Issue.Position;
+
 
 /**
  * @author Sergey Polovko
@@ -37,4 +38,29 @@ public void testToString() {
             "  11:22: #4 message (S_WARNING)\n" +
             "  11:22 at file.cpp: #5 message (S_WARNING)", x.toString());
     }
+
+    @Test
+    public void testEquals() {
+        Issue nested1 = Issue.of(1, "nested 1", Issue.Severity.WARNING);
+        Issue nested2 = Issue.of(2, "nested 2", Issue.Severity.WARNING);
+
+        Issue plain = Issue.of(7, "cause", Issue.Severity.FATAL);
+        Issue samePlain = Issue.of(7, "cause", Issue.Severity.FATAL);
+
+        Assert.assertEquals(plain, samePlain);
+        Assert.assertEquals(plain.hashCode(), samePlain.hashCode());
+        Assert.assertNotEquals(plain, Issue.of(8, "root cause", Issue.Severity.FATAL));
+        Assert.assertNotEquals(plain, null);
+
+        Issue withNested = Issue.of(Position.EMPTY, Position.EMPTY, 7, "cause", Issue.Severity.FATAL, nested1);
+        Issue withSameNested = Issue.of(Position.EMPTY, Position.EMPTY, 7, "cause", Issue.Severity.FATAL, nested1);
+        Issue withOtherNested = Issue.of(Position.EMPTY, Position.EMPTY, 7, "cause", Issue.Severity.FATAL, nested2);
+
+        Assert.assertEquals(withNested, withSameNested);
+        Assert.assertEquals(withNested.hashCode(), withSameNested.hashCode());
+
+        // issues differing only in their nested issues are different issues
+        Assert.assertNotEquals(withNested, withOtherNested);
+        Assert.assertNotEquals(withNested, plain);
+    }
 }
diff --git a/query/src/test/java/tech/ydb/query/impl/QueryIntegrationTest.java b/query/src/test/java/tech/ydb/query/impl/QueryIntegrationTest.java
index f45a22ac1..5655254b4 100644
--- a/query/src/test/java/tech/ydb/query/impl/QueryIntegrationTest.java
+++ b/query/src/test/java/tech/ydb/query/impl/QueryIntegrationTest.java
@@ -610,9 +610,13 @@ public void testNoTxStatement() {
 
                 Assert.assertFalse(result.isSuccess());
                 Assert.assertEquals(StatusCode.PRECONDITION_FAILED, result.getStatus().getCode());
-                Issue issue =  Issue.of(2012,
+                Issue issue = Issue.of(
+                        Issue.Position.EMPTY,
+                        Issue.Position.EMPTY,
+                        2012,
                         "Constraint violated. Table: `" + ydbTransport.getDatabase() + "/" + TEST_TABLE + "`.",
-                        Issue.Severity.ERROR
+                        Issue.Severity.ERROR,
+                        Issue.of(2012, "Conflict with existing key.", Issue.Severity.ERROR)
                 );
                 Assert.assertArrayEquals(new Issue[] { issue }, result.getStatus().getIssues());