Add unit test for negative values in ByteBufferStreamInput::readVLong (elastic#115749)

Author: ChrisHegarty

server/src/test/java/org/elasticsearch/common/io/stream/ByteBufferStreamInputTests.java

@@ -21,4 +21,52 @@ protected StreamInput getStreamInput(BytesReference bytesReference) throws IOExc
         final BytesRef bytesRef = bytesReference.toBytesRef();
         return new ByteBufferStreamInput(ByteBuffer.wrap(bytesRef.bytes, bytesRef.offset, bytesRef.length));
     }
+
+    public void testReadVLongNegative() throws IOException {
+        for (int i = 0; i < 1024; i++) {
+            long write = randomNegativeLong();
+            BytesStreamOutput out = new BytesStreamOutput();
+            out.writeVLongNoCheck(write);
+            long read = getStreamInput(out.bytes()).readVLong();
+            assertEquals(write, read);
+        }
+    }
+
+    public void testReadVLongBounds() throws IOException {
+        long write = Long.MAX_VALUE;
+        BytesStreamOutput out = new BytesStreamOutput();
+        out.writeVLongNoCheck(write);
+        long read = getStreamInput(out.bytes()).readVLong();
+        assertEquals(write, read);
+
+        write = Long.MIN_VALUE;
+        out = new BytesStreamOutput();
+        out.writeVLongNoCheck(write);
+        read = getStreamInput(out.bytes()).readVLong();
+        assertEquals(write, read);
+    }
+
+    public void testReadVIntNegative() throws IOException {
+        for (int i = 0; i < 1024; i++) {
+            int write = randomNegativeInt();
+            BytesStreamOutput out = new BytesStreamOutput();
+            out.writeVInt(write);
+            int read = getStreamInput(out.bytes()).readVInt();
+            assertEquals(write, read);
+        }
+    }
+
+    public void testReadVIntBounds() throws IOException {
+        int write = Integer.MAX_VALUE;
+        BytesStreamOutput out = new BytesStreamOutput();
+        out.writeVInt(write);
+        long read = getStreamInput(out.bytes()).readVInt();
+        assertEquals(write, read);
+
+        write = Integer.MIN_VALUE;
+        out = new BytesStreamOutput();
+        out.writeVInt(write);
+        read = getStreamInput(out.bytes()).readVInt();
+        assertEquals(write, read);
+    }
 }

test/framework/src/main/java/org/elasticsearch/test/ESTestCase.java

@@ -1032,6 +1032,13 @@ public static long randomNonNegativeLong() {
         return randomLong() & Long.MAX_VALUE;
     }
 
+    /**
+     * @return a <code>long</code> between <code>Long.MIN_VALUE</code> and <code>-1</code>  (inclusive) chosen uniformly at random.
+     */
+    public static long randomNegativeLong() {
+        return randomLong() | Long.MIN_VALUE;
+    }
+
     /**
      * @return an <code>int</code> between <code>0</code> and <code>Integer.MAX_VALUE</code> (inclusive) chosen uniformly at random.
      */