implement validations of pagination URLs

javatests/org/chromium/distiller/PageParamInfoTest.java

Index: javatests/org/chromium/distiller/PageParamInfoTest.java
diff --git a/javatests/org/chromium/distiller/PageParamInfoTest.java b/javatests/org/chromium/distiller/PageParamInfoTest.java
new file mode 100644
index 0000000000000000000000000000000000000000..8712b0b747934cffa651fca3e20b745e017cac8b
--- /dev/null
+++ b/javatests/org/chromium/distiller/PageParamInfoTest.java
@@ -0,0 +1,97 @@
+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.distiller;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+public class PageParamInfoTest extends DomDistillerJsTestCase {
+
+    public void testArePageNumsAdjacentAndConsecutive() {
+        {
+            final int[] allNums = { 1, 2 };
+            final int[] selectedNums = { 1, 2 };
+            int result = arePageNumsAdjacentAndConsecutive(selectedNums, allNums);
+            assertTrue(isAdjacent(result));
+            assertTrue(isConsecutive(result));
+        }
+        {
+            final int[] allNums = { 1, 2, 3 };
+            final int[] selectedNums = { 2, 3 };
+            int result = arePageNumsAdjacentAndConsecutive(selectedNums, allNums);
+            assertTrue(isAdjacent(result));
+            assertTrue(isConsecutive(result));
+        }
+        {
+            final int[] allNums = { 1, 5, 6, 7, 10 };
+            final int[] selectedNums = { 1, 5, 7, 10 };
+            int result = arePageNumsAdjacentAndConsecutive(selectedNums, allNums);
+            assertTrue(isAdjacent(result));
+            assertTrue(isConsecutive(result));
+        }
+        {
+            final int[] allNums = { 10, 25, 50 };
+            final int[] selectedNums = { 10, 25, 50 };  // No consecutive pairs.
+            int result = arePageNumsAdjacentAndConsecutive(selectedNums, allNums);
+            assertTrue(isAdjacent(result));
+            assertFalse(isConsecutive(result));
+        }
+        {
+            final int[] allNums = { 23, 24, 30 };
+            // This list doesn't satisfy consecutive rule. There should be "22" on the left of "23",
+            // or "25" on the right of "24", or "29" on the left of "30".
+            final int[] selectedNums = { 23, 24, 30 };
+            int result = arePageNumsAdjacentAndConsecutive(selectedNums, allNums);
+            assertTrue(isAdjacent(result));
+            assertFalse(isConsecutive(result));
+        }
+        {
+            final int[] allNums = { 1, 2, 3, 4, 5 };
+            final int[] selectedNums = { 1, 3, 5 };  // Two gaps.
+            int result = arePageNumsAdjacentAndConsecutive(selectedNums, allNums);
+            assertFalse(isAdjacent(result));
+            assertFalse(isConsecutive(result));
+        }
+        {
+            final int[] allNums = { 2, 3, 4, 5 };
+            final int[] selectedNums = { 2, 5 };  // A gap of 2 numbers.
+            int result = arePageNumsAdjacentAndConsecutive(selectedNums, allNums);
+            assertFalse(isAdjacent(result));
+            assertFalse(isConsecutive(result));
+        }
+    }
+
+    private static int arePageNumsAdjacentAndConsecutive(int[] selectedNums, int[] allNums) {
+        List<PageParamInfo.PageInfo> ascendingNumbers = new ArrayList<PageParamInfo.PageInfo>();
+        Map<Integer, Integer> numberToPos = new HashMap<Integer, Integer>();
+
+        for (int i = 0; i < allNums.length; i++) {
+            final int number = allNums[i];
+            numberToPos.put(number, i);
+            ascendingNumbers.add(new PageParamInfo.PageInfo(number, ""));
+        }
+
+        List<PageLinkInfo> allLinkInfo = new ArrayList<PageLinkInfo>();
+        for (int i = 0; i < selectedNums.length; i++) {
+            final int number = selectedNums[i];
+            allLinkInfo.add(new PageLinkInfo(number, number, numberToPos.get(number)));
+        }
+
+        return PageParamInfo.arePageNumsAdjacentAndConsecutive(allLinkInfo, ascendingNumbers);
+    }
+
+    private static boolean isAdjacent(int result) {
+        return (result & PageParamInfo.PAGE_NUM_ADJACENT_MASK) ==
+                PageParamInfo.PAGE_NUM_ADJACENT_MASK;
+    }
+
+    private static boolean isConsecutive(int result) {
+        return (result & PageParamInfo.PAGE_NUM_CONSECUTIVE_MASK) ==
+                PageParamInfo.PAGE_NUM_CONSECUTIVE_MASK;
+    }
+
+}