Fix Bug - handle unsigned long in assertion of LongHashSet

Signed-off-by: Shailesh Singh <[email protected]>

Author: Shailesh Singh

server/src/main/java/org/apache/lucene/util/UnsignedLongHashSet.java

@@ -0,0 +1,137 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.apache.lucene.util;
+
+import org.apache.lucene.util.packed.PackedInts;
+import org.opensearch.common.Numbers;
+
+import java.util.Arrays;
+import java.util.Objects;
+import java.util.stream.Collectors;
+import java.util.stream.LongStream;
+
+/** Set of longs, optimized for docvalues usage */
+public final class UnsignedLongHashSet implements Accountable {
+    private static final long BASE_RAM_BYTES = RamUsageEstimator.shallowSizeOfInstance(UnsignedLongHashSet.class);
+
+    private static final long MISSING = Numbers.MIN_UNSIGNED_LONG_VALUE_AS_LONG;
+
+    final long[] table;
+    final int mask;
+    final boolean hasMissingValue;
+    final int size;
+    /** minimum value in the set, or Long.MAX_VALUE for an empty set */
+    public final long minValue;
+    /** maximum value in the set, or Long.MIN_VALUE for an empty set */
+    public final long maxValue;
+
+    /** Construct a set. Values must be in sorted order. */
+    public UnsignedLongHashSet(long[] values) {
+        int tableSize = Math.toIntExact(values.length * 3L / 2);
+        tableSize = 1 << PackedInts.bitsRequired(tableSize); // make it a power of 2
+        assert tableSize >= values.length * 3L / 2;
+        table = new long[tableSize];
+        Arrays.fill(table, MISSING);
+        mask = tableSize - 1;
+        boolean hasMissingValue = false;
+        int size = 0;
+        long previousValue = 0; // for assert
+        for (long value : values) {
+            if (value == MISSING) {
+                size += hasMissingValue ? 0 : 1;
+                hasMissingValue = true;
+            } else if (add(value)) {
+                ++size;
+            }
+            assert Long.compareUnsigned(value, previousValue) >= 0 : " values must be provided in sorted order";
+            previousValue = value;
+        }
+        this.hasMissingValue = hasMissingValue;
+        this.size = size;
+        this.minValue = values.length == 0 ? Numbers.MAX_UNSIGNED_LONG_VALUE_AS_LONG : values[0];
+        this.maxValue = values.length == 0 ? Numbers.MIN_UNSIGNED_LONG_VALUE_AS_LONG : values[values.length - 1];
+    }
+
+    private boolean add(long l) {
+        assert l != MISSING;
+        final int slot = Long.hashCode(l) & mask;
+        for (int i = slot;; i = (i + 1) & mask) {
+            if (table[i] == MISSING) {
+                table[i] = l;
+                return true;
+            } else if (table[i] == l) {
+                // already added
+                return false;
+            }
+        }
+    }
+
+    /**
+     * check for membership in the set.
+     *
+     * <p>You should use {@link #minValue} and {@link #maxValue} to guide/terminate iteration before
+     * calling this.
+     */
+    public boolean contains(long l) {
+        if (l == MISSING) {
+            return hasMissingValue;
+        }
+        final int slot = Long.hashCode(l) & mask;
+        for (int i = slot;; i = (i + 1) & mask) {
+            if (table[i] == MISSING) {
+                return false;
+            } else if (table[i] == l) {
+                return true;
+            }
+        }
+    }
+
+    /** returns a stream of all values contained in this set */
+    LongStream stream() {
+        LongStream stream = Arrays.stream(table).filter(v -> v != MISSING);
+        if (hasMissingValue) {
+            stream = LongStream.concat(LongStream.of(MISSING), stream);
+        }
+        return stream;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(size, minValue, maxValue, mask, hasMissingValue, Arrays.hashCode(table));
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (obj != null && obj instanceof UnsignedLongHashSet) {
+            UnsignedLongHashSet that = (UnsignedLongHashSet) obj;
+            return size == that.size
+                && minValue == that.minValue
+                && maxValue == that.maxValue
+                && mask == that.mask
+                && hasMissingValue == that.hasMissingValue
+                && Arrays.equals(table, that.table);
+        }
+        return false;
+    }
+
+    @Override
+    public String toString() {
+        return stream().mapToObj(String::valueOf).collect(Collectors.joining(", ", "[", "]"));
+    }
+
+    /** number of elements in the set */
+    public int size() {
+        return size;
+    }
+
+    @Override
+    public long ramBytesUsed() {
+        return BASE_RAM_BYTES + RamUsageEstimator.sizeOfObject(table);
+    }
+}

server/src/main/java/org/opensearch/index/document/SortedUnsignedLongDocValuesSetQuery.java

@@ -25,7 +25,8 @@
 import org.apache.lucene.search.ScorerSupplier;
 import org.apache.lucene.search.TwoPhaseIterator;
 import org.apache.lucene.search.Weight;
-import org.apache.lucene.util.LongHashSet;
+
+import org.apache.lucene.util.UnsignedLongHashSet;
 
 import java.io.IOException;
 import java.math.BigInteger;
@@ -40,12 +41,12 @@
 public abstract class SortedUnsignedLongDocValuesSetQuery extends Query {
 
     private final String field;
-    private final LongHashSet numbers;
+    private final UnsignedLongHashSet numbers;
 
     SortedUnsignedLongDocValuesSetQuery(String field, BigInteger[] numbers) {
         this.field = Objects.requireNonNull(field);
         Arrays.sort(numbers);
-        this.numbers = new LongHashSet(Arrays.stream(numbers).mapToLong(n -> n.longValue()).toArray());
+        this.numbers = new UnsignedLongHashSet(Arrays.stream(numbers).mapToLong(n -> n.longValue()).toArray());
     }
 
     @Override