implement validations of pagination URLs

javatests/org/chromium/distiller/PathComponentPagePatternTest.java

Index: javatests/org/chromium/distiller/PathComponentPagePatternTest.java
diff --git a/javatests/org/chromium/distiller/PathComponentPagePatternTest.java b/javatests/org/chromium/distiller/PathComponentPagePatternTest.java
new file mode 100644
index 0000000000000000000000000000000000000000..f8426677ec018baf0b146c0dc2bb89322d144ac3
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+++ b/javatests/org/chromium/distiller/PathComponentPagePatternTest.java
@@ -0,0 +1,151 @@
+// 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 com.google.gwt.regexp.shared.MatchResult;
+import com.google.gwt.regexp.shared.RegExp;
+
+public class PathComponentPagePatternTest extends DomDistillerJsTestCase {
+    private static final String PAGE_PARAM_VALUE = "8";
+    private static final RegExp sDigitsRegExp = RegExp.compile("(\\d+)", "gi");
+
+    public void testIsPagingUrl() {
+        assertTrue(isPagingUrl("http://www.foo.com/a/abc-2.html",
+                               "http://www.foo.com/a/abc-[*!].html"));
+        assertTrue(isPagingUrl("http://www.foo.com/a/abc.html",
+                               "http://www.foo.com/a/abc-[*!].html"));
+        assertTrue(isPagingUrl("http://www.foo.com/a/abc", "http://www.foo.com/a/abc-[*!]"));
+        assertTrue(isPagingUrl("http://www.foo.com/a/abc-2", "http://www.foo.com/a/abc-[*!]"));
+        assertTrue(isPagingUrl("http://www.foo.com/a/b-c-3", "http://www.foo.com/a/b-[*!]-c-3"));
+        assertTrue(isPagingUrl("http://www.foo.com/a-c-3", "http://www.foo.com/a-[*!]-c-3"));
+        assertTrue(isPagingUrl("http://www.foo.com/a-p-1-c-3", "http://www.foo.com/a-p-[*!]-c-3"));
+        assertFalse(isPagingUrl("http://www.foo.com/a/abc-page", "http://www.foo.com/a/abc-[*!]"));
+        assertFalse(isPagingUrl("http://www.foo.com/a/2", "http://www.foo.com/a/abc-[*!]"));
+        assertFalse(isPagingUrl("http://www.foo.com/a", "http://www.foo.com/a/abc-[*!]"));
+        assertFalse(isPagingUrl("http://www.foo.com/a/abc.html",
+                                "http://www.foo.com/a/abc[*!].html"));
+
+        assertTrue(isPagingUrl("http://www.foo.com/a/page/2", "http://www.foo.com/a/page/[*!]"));
+        assertTrue(isPagingUrl("http://www.foo.com/a", "http://www.foo.com/a/page/[*!]"));
+        assertTrue(isPagingUrl("http://www.foo.com/a/page/2/abc.html",
+                               "http://www.foo.com/a/page/[*!]/abc.html"));
+        assertTrue(isPagingUrl("http://www.foo.com/a/abc.html",
+                               "http://www.foo.com/a/page/[*!]/abc.html"));
+        assertTrue(isPagingUrl("http://www.foo.com/a/abc.html",
+                               "http://www.foo.com/a/[*!]/abc.html"));
+        assertTrue(isPagingUrl("http://www.foo.com/a/2/abc.html",
+                               "http://www.foo.com/a/[*!]/abc.html"));
+        assertTrue(isPagingUrl("http://www.foo.com/abc.html",
+                               "http://www.foo.com/a/[*!]/abc.html"));
+        assertTrue(isPagingUrl("http://www.foo.com/a/page/2page",
+                               "http://www.foo.com/a/page/[*!]page"));
+        assertFalse(isPagingUrl("http://www.foo.com/a/page/2",
+                                "http://www.foo.com/a/page/[*!]page"));
+        assertFalse(isPagingUrl("http://www.foo.com/a/page/b", "http://www.foo.com/a/page/[*!]"));
+        assertFalse(isPagingUrl("http://www.foo.com/m/page/2", "http://www.foo.com/p/page/[*!]"));
+    }
+
+    public void testIsPagePatternValid() {
+        assertTrue(isPagePatternValid("http://www.google.com/forum-12",
+                "http://www.google.com/forum-12/page/[*!]"));
+        assertTrue(isPagePatternValid("http://www.google.com/forum-12",
+                "http://www.google.com/forum-12/[*!]"));
+        assertTrue(isPagePatternValid("http://www.google.com/forum-12",
+                "http://www.google.com/forum-12/page-[*!]"));
+
+        assertTrue(isPagePatternValid("http://www.google.com/forum-12/food",
+                "http://www.google.com/forum-12/food/for/bar/[*!]"));
+        assertTrue(isPagePatternValid("http://www.google.com/forum-12-food",
+                "http://www.google.com/forum-12-food-[*!]"));
+
+        assertFalse(isPagePatternValid("http://www.google.com/forum-12/food",
+                "http://www.google.com/forum-12/food/2012/01/[*!]"));
+        assertFalse(isPagePatternValid("http://www.google.com/forum-12/food/2012/01/01",
+                "http://www.google.com/forum-12/food/2012/01/[*!]"));
+
+        assertTrue(isPagePatternValid("http://www.google.com/thread/12",
+                "http://www.google.com/thread/12/page/[*!]"));
+        assertFalse(isPagePatternValid("http://www.google.com/thread/12/foo",
+                "http://www.google.com/thread/12/page/[*!]/foo"));
+        assertTrue(isPagePatternValid("http://www.google.com/thread/12/foo",
+                "http://www.google.com/thread/12/[*!]/foo"));
+    }
+
+    public void testIsLastNumericPathComponentBad() {
+        // Path component is not numeric i.e. contains non-digits.
+        String url = "http://www.foo.com/a2";
+        int digitStart = url.indexOf("2");
+        assertFalse(isLastNumericPathComponentBad(url, digitStart));
+
+        // Numeric path component is first.
+        url = "http://www.foo.com/2";
+        digitStart = url.indexOf("2");
+        assertFalse(isLastNumericPathComponentBad(url, digitStart));
+
+        // Numeric path component follows a path component that is not a bad page param name.
+        url = "http://www.foo.com/good/2";
+        digitStart = url.indexOf("2");
+        assertFalse(isLastNumericPathComponentBad(url, digitStart));
+
+        // Numeric path component follows a path component that is a bad page param name.
+        url = "http://www.foo.com/wiki/2";
+        digitStart = url.indexOf("2");
+        assertTrue(isLastNumericPathComponentBad(url, digitStart));
+
+        // (s)htm(l) extension doesn't follow digit.
+        url = "http://www.foo.com/2a";
+        digitStart = url.indexOf("2");
+        assertFalse(isLastNumericPathComponentBad(url, digitStart));
+
+        // .htm follows digit, previous path component is not a bad page param name.
+        url = "http://www.foo.com/good/2.htm";
+        digitStart = url.indexOf("2");
+        assertFalse(isLastNumericPathComponentBad(url, digitStart));
+
+        // .html follows digit, previous path component is a bad page param name.
+        url = "http://www.foo.com/wiki/2.html";
+        digitStart = url.indexOf("2");
+        assertTrue(isLastNumericPathComponentBad(url, digitStart));
+
+        // .shtml follows digit, previous path component is not a bad page param name, but the one
+        // before that is.
+        url = "http://www.foo.com/wiki/good/2.shtml";
+        digitStart = url.indexOf("2");
+        assertFalse(isLastNumericPathComponentBad(url, digitStart));
+    }
+
+    private static boolean isPagingUrl(String urlStr, String patternStr) {
+        ParsedUrl url = ParsedUrl.create(urlStr);
+        PageParameterDetector.PagePattern pattern = createPagePattern(patternStr);
+        assertTrue(pattern != null);
+        return pattern.isPagingUrl(urlStr);
+    }
+
+    private static boolean isPagePatternValid(String urlStr, String patternStr) {
+        ParsedUrl url = ParsedUrl.create(urlStr);
+        assertTrue(url != null);
+        PageParameterDetector.PagePattern pattern = createPagePattern(patternStr);
+        assertTrue(pattern != null);
+        return pattern.isValidFor(url);
+    }
+
+    private static boolean isLastNumericPathComponentBad(String url, int digitStart) {
+        return PathComponentPagePattern.isLastNumericPathComponentBad(url, 18, digitStart,
+                digitStart + 1);
+    }
+
+    private static PageParameterDetector.PagePattern createPagePattern(String patternStr) {
+        int pathStart = patternStr.indexOf('/');
+        int digitStart = patternStr.indexOf(PageParameterDetector.PAGE_PARAM_PLACEHOLDER);
+        sDigitsRegExp.setLastIndex(digitStart);
+        String oriUrlStr = patternStr.replace(PageParameterDetector.PAGE_PARAM_PLACEHOLDER,
+                PAGE_PARAM_VALUE);
+        MatchResult match = sDigitsRegExp.exec(oriUrlStr);
+        if (match == null) return null;
+        return PathComponentPagePattern.create(ParsedUrl.create(oriUrlStr), pathStart, digitStart,
+                sDigitsRegExp.getLastIndex());
+    }
+
+}