More randomized testing and fixes

Author: felixbarny

server/src/main/java/org/elasticsearch/common/hash/BufferedMurmur3Hasher.java

@@ -83,7 +83,7 @@ public void addString(String value) {
     public void addLong(long value) {
         flushIfRemainingCapacityLowerThan(Long.BYTES);
         ByteUtils.writeLongLE(value, buffer, pos);
-        pos = Long.BYTES;
+        pos += Long.BYTES;
     }
 
     /**
@@ -97,7 +97,7 @@ public void addLongs(long v1, long v2) {
         flushIfRemainingCapacityLowerThan(Long.BYTES * 2);
         ByteUtils.writeLongLE(v1, buffer, pos);
         ByteUtils.writeLongLE(v2, buffer, pos + 8);
-        pos = Long.BYTES * 2;
+        pos += Long.BYTES * 2;
     }
 
     /**
@@ -115,7 +115,7 @@ public void addLongs(long v1, long v2, long v3, long v4) {
         ByteUtils.writeLongLE(v2, buffer, pos + 8);
         ByteUtils.writeLongLE(v3, buffer, pos + 16);
         ByteUtils.writeLongLE(v4, buffer, pos + 24);
-        pos = Long.BYTES * 4;
+        pos += Long.BYTES * 4;
     }
 
     private void ensureCapacity(int requiredBufferLength) {

server/src/test/java/org/elasticsearch/common/hash/BufferedMurmur3HasherTests.java

@@ -15,7 +15,7 @@
 
 public class BufferedMurmur3HasherTests extends ESTestCase {
 
-    private final BufferedMurmur3Hasher bufferedHasher = new BufferedMurmur3Hasher(0);
+    private final BufferedMurmur3Hasher bufferedHasher = new BufferedMurmur3Hasher(0, randomIntBetween(32, 128));
     private final Murmur3Hasher hasher = new Murmur3Hasher(0);
 
     public void testAddString() {
@@ -41,14 +41,36 @@ public void testAddLong() {
         assertEquals(hasher.digestHash(), bufferedHasher.digestHash());
     }
 
+    public void testAddLongs() {
+        long value1 = randomLong();
+        long value2 = randomLong();
+        long value3 = randomLong();
+        long value4 = randomLong();
+        bufferedHasher.addLong(value1);
+        bufferedHasher.addLongs(value1, value2);
+        bufferedHasher.addLongs(value1, value2, value3, value4);
+
+        hasher.update(toBytes(value1));
+
+        hasher.update(toBytes(value1));
+        hasher.update(toBytes(value2));
+
+        hasher.update(toBytes(value1));
+        hasher.update(toBytes(value2));
+        hasher.update(toBytes(value3));
+        hasher.update(toBytes(value4));
+
+        assertEquals(hasher.digestHash(), bufferedHasher.digestHash());
+    }
+
     public void testAddTwoLongs() {
         long value1 = randomLong();
         long value2 = randomLong();
 
         bufferedHasher.addLongs(value1, value2);
 
-        hasher.update(toBytes(value1), 0, Long.BYTES);
-        hasher.update(toBytes(value2), 0, Long.BYTES);
+        hasher.update(toBytes(value1));
+        hasher.update(toBytes(value2));
 
         assertEquals(hasher.digestHash(), bufferedHasher.digestHash());
     }
@@ -61,15 +83,15 @@ public void testAddFourLongs() {
 
         bufferedHasher.addLongs(value1, value2, value3, value4);
 
-        hasher.update(toBytes(value1), 0, Long.BYTES);
-        hasher.update(toBytes(value2), 0, Long.BYTES);
-        hasher.update(toBytes(value3), 0, Long.BYTES);
-        hasher.update(toBytes(value4), 0, Long.BYTES);
+        hasher.update(toBytes(value1));
+        hasher.update(toBytes(value2));
+        hasher.update(toBytes(value3));
+        hasher.update(toBytes(value4));
 
         assertEquals(hasher.digestHash(), bufferedHasher.digestHash());
     }
 
-    public void randomAdds() {
+    public void testRandomAdds() {
         int numAdds = randomIntBetween(128, 1024);
         for (int i = 0; i < numAdds; i++) {
             switch (randomIntBetween(0, 4)) {