From 04532220152a69a04064537daffd9e57953b81c0 Mon Sep 17 00:00:00 2001
From: feijermu <seedeed@qq.com>
Date: Mon, 2 Mar 2020 15:38:45 +0800
Subject: [PATCH] Add test cases for MathUtil. (#10071)

Motivation:

MathUtil needs more test cases.

Modification:

Add several test cases for MathUtil.

Result:

Improve test coverage slightly.
---
 .../io/netty/util/internal/MathUtilTest.java  | 88 +++++++++++++++++++
 1 file changed, 88 insertions(+)
 create mode 100644 common/src/test/java/io/netty/util/internal/MathUtilTest.java

diff --git a/common/src/test/java/io/netty/util/internal/MathUtilTest.java b/common/src/test/java/io/netty/util/internal/MathUtilTest.java
new file mode 100644
index 0000000000..16616b8897
--- /dev/null
+++ b/common/src/test/java/io/netty/util/internal/MathUtilTest.java
@@ -0,0 +1,88 @@
+/*
+ * Copyright 2020 The Netty Project
+ *
+ * The Netty Project licenses this file to you 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 io.netty.util.internal;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+import static io.netty.util.internal.MathUtil.*;
+
+import org.junit.Test;
+
+public class MathUtilTest {
+
+    @Test
+    public void testFindNextPositivePowerOfTwo() {
+        assertEquals(1, findNextPositivePowerOfTwo(0));
+        assertEquals(1, findNextPositivePowerOfTwo(1));
+        assertEquals(1024, findNextPositivePowerOfTwo(1000));
+        assertEquals(1024, findNextPositivePowerOfTwo(1023));
+        assertEquals(2048, findNextPositivePowerOfTwo(2048));
+        assertEquals(1 << 30, findNextPositivePowerOfTwo((1 << 30) - 1));
+        assertEquals(1, findNextPositivePowerOfTwo(-1));
+        assertEquals(1, findNextPositivePowerOfTwo(-10000));
+    }
+
+    @Test
+    public void testSafeFindNextPositivePowerOfTwo() {
+        assertEquals(1, safeFindNextPositivePowerOfTwo(0));
+        assertEquals(1, safeFindNextPositivePowerOfTwo(1));
+        assertEquals(1024, safeFindNextPositivePowerOfTwo(1000));
+        assertEquals(1024, safeFindNextPositivePowerOfTwo(1023));
+        assertEquals(2048, safeFindNextPositivePowerOfTwo(2048));
+        assertEquals(1 << 30, safeFindNextPositivePowerOfTwo((1 << 30) - 1));
+        assertEquals(1, safeFindNextPositivePowerOfTwo(-1));
+        assertEquals(1, safeFindNextPositivePowerOfTwo(-10000));
+        assertEquals(1 << 30, safeFindNextPositivePowerOfTwo(Integer.MAX_VALUE));
+        assertEquals(1 << 30, safeFindNextPositivePowerOfTwo((1 << 30) + 1));
+        assertEquals(1, safeFindNextPositivePowerOfTwo(Integer.MIN_VALUE));
+        assertEquals(1, safeFindNextPositivePowerOfTwo(Integer.MIN_VALUE + 1));
+    }
+
+    @Test
+    public void testIsOutOfBounds() {
+        assertFalse(isOutOfBounds(0, 0, 0));
+        assertFalse(isOutOfBounds(0, 0, 1));
+        assertFalse(isOutOfBounds(0, 1, 1));
+        assertTrue(isOutOfBounds(1, 1, 1));
+        assertTrue(isOutOfBounds(Integer.MAX_VALUE, 1, 1));
+        assertTrue(isOutOfBounds(Integer.MAX_VALUE, Integer.MAX_VALUE, 1));
+        assertTrue(isOutOfBounds(Integer.MAX_VALUE, Integer.MAX_VALUE, Integer.MAX_VALUE));
+        assertFalse(isOutOfBounds(0, Integer.MAX_VALUE, Integer.MAX_VALUE));
+        assertFalse(isOutOfBounds(0, Integer.MAX_VALUE - 1, Integer.MAX_VALUE));
+        assertTrue(isOutOfBounds(0, Integer.MAX_VALUE, Integer.MAX_VALUE - 1));
+        assertFalse(isOutOfBounds(Integer.MAX_VALUE - 1, 1, Integer.MAX_VALUE));
+        assertTrue(isOutOfBounds(Integer.MAX_VALUE - 1, 1, Integer.MAX_VALUE - 1));
+        assertTrue(isOutOfBounds(Integer.MAX_VALUE - 1, 2, Integer.MAX_VALUE));
+        assertTrue(isOutOfBounds(1, Integer.MAX_VALUE, Integer.MAX_VALUE));
+    }
+
+    @Test
+    public void testCompare() {
+        assertEquals(-1, compare(0, 1));
+        assertEquals(-1, compare(0L, 1L));
+        assertEquals(-1, compare(0, Integer.MAX_VALUE));
+        assertEquals(-1, compare(0L, Long.MAX_VALUE));
+        assertEquals(0, compare(0, 0));
+        assertEquals(0, compare(0L, 0L));
+        assertEquals(0, compare(Integer.MIN_VALUE, Integer.MIN_VALUE));
+        assertEquals(0, compare(Long.MIN_VALUE, Long.MIN_VALUE));
+        assertEquals(1, compare(Integer.MAX_VALUE, 0));
+        assertEquals(1, compare(Integer.MAX_VALUE, Integer.MAX_VALUE - 1));
+        assertEquals(1, compare(Long.MAX_VALUE, 0L));
+        assertEquals(1, compare(Long.MAX_VALUE, Long.MAX_VALUE - 1));
+    }
+}