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danfickledanfickle
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#482 #483 #491 Basic fuzz testing of the line breaking algorithms.
This should ensure no infinite loop bugs creep in over time.
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‎openhtmltopdf-examples/src/test/java/com/openhtmltopdf/nonvisualregressiontests/NonVisualRegressionTest.java‎

Lines changed: 141 additions & 1 deletion
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@@ -9,7 +9,10 @@
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import java.io.File;
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import java.io.IOException;
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import java.util.ArrayList;
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import java.util.Arrays;
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import java.util.List;
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import java.util.Locale;
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import java.util.Random;
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import org.apache.commons.io.FileUtils;
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import org.apache.pdfbox.io.IOUtils;
@@ -29,11 +32,11 @@
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import org.apache.pdfbox.util.Charsets;
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import org.hamcrest.CustomTypeSafeMatcher;
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import org.junit.Assert;
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import org.junit.Ignore;
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import org.junit.Test;
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import com.openhtmltopdf.pdfboxout.PdfRendererBuilder;
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import com.openhtmltopdf.testcases.TestcaseRunner;
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import com.openhtmltopdf.visualregressiontests.VisualRegressionTest;
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import com.openhtmltopdf.visualtest.TestSupport;
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import com.openhtmltopdf.visualtest.VisualTester.BuilderConfig;
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@@ -821,6 +824,143 @@ public void testPR480LinkShapes() throws IOException {
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}
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}
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/**
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* Runs a fuzz test, optionally with PDFBOX included font with non-zero-width
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* soft hyphen.
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*/
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private static void runFuzzTest(String html, boolean useFont) throws IOException {
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final String header = useFont ?
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"<html><body style=\"font-family: 'Liberation Sans'\">" :
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"<html><body>";
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final String footer = "</body></html>";
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System.out.println("The test is " + html.length() + " chars long.");
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try (ByteArrayOutputStream os = new ByteArrayOutputStream()) {
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PdfRendererBuilder builder = new PdfRendererBuilder();
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builder.useFastMode();
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builder.toStream(os);
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builder.withHtmlContent(header + html + footer, null);
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if (useFont) {
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builder.useFont(() -> VisualRegressionTest.class.getClassLoader().getResourceAsStream("org/apache/pdfbox/resources/ttf/LiberationSans-Regular.ttf"),
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"Liberation Sans");
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}
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builder.run();
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// Files.write(Paths.get("./target/html.txt"), html.getBytes(StandardCharsets.UTF_8));
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// Files.write(Paths.get("./target/pdf.pdf"), os.toByteArray());
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System.out.println("The result is " + os.size() + " bytes long.");
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}
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}
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/**
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* Creates a fuzz test with random characters given the styles provided in
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* arguments.
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*/
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private static void createCombinationTest(
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StringBuilder sb, int widthPx, String whiteSpace, String wordWrap, List<char[]> all, Random rndm, int testCharCount) {
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String start = String.format(Locale.US, "<div style=\"white-space: %s; word-wrap: %s; width: %dpx;\">",
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whiteSpace, wordWrap, widthPx);
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String end = "</div>";
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sb.append(start);
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int len = 0;
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while (true) {
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char[] charCombi = all.get(rndm.nextInt(all.size()));
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if (len + charCombi.length > testCharCount) {
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String combi = String.valueOf(charCombi);
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sb.append(combi.substring(0, testCharCount - len));
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break;
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}
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sb.append(charCombi);
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len += charCombi.length;
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}
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sb.append(end);
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}
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/**
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* Creates all 5 character combinations from a list of characters
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* which have special meaning to the line breaking algorithms.
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*/
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private static List<char[]> createAllCombinations() {
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char[] chars = new char[] { 'x', '\u00ad', '\n', '\r', ' ' };
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int[] loopIndices = new int[chars.length];
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int totalCombinations = (int) Math.pow(loopIndices.length, loopIndices.length);
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List<char[]> ret = new ArrayList<>(totalCombinations);
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for (int i = 0; i < totalCombinations; i++) {
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char[] result = new char[loopIndices.length];
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for (int k = 0; k < loopIndices.length; k++) {
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char ch = chars[loopIndices[k]];
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result[k] = ch;
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}
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ret.add(result);
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boolean carry = true;
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for (int j = loopIndices.length - 1; j >= 0; j--) {
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if (carry) {
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loopIndices[j]++;
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carry = false;
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}
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if (loopIndices[j] >= chars.length) {
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loopIndices[j] = 0;
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carry = true;
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}
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}
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}
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return ret;
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}
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/**
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* Tests the line breaking algorithms against infinite loop bugs
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* by using many combinations of styles and random character sequences.
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*/
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@Test
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public void testPr492InfiniteLoopBugsInLineBreakingFuzz() throws IOException {
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final String[] whiteSpace = new String[] { "normal", "pre", "nowrap", "pre-wrap", "pre-line" };
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final String[] wordWrap = new String[] { "normal", "break-word" };
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final List<char[]> all = createAllCombinations();
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final Random rndm = new Random();
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long seed = rndm.nextLong();
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System.out.println("For NonVisualRegressionTest::testPr492InfiniteLoopBugsInLineBreakingFuzz " +
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"using a random seed of " + seed + " for Random instance.");
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rndm.setSeed(seed);
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List<Integer> lengths = new ArrayList<>();
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lengths.addAll(Arrays.asList(0, 1, 2, 3, 37, 79));
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for (int i = 0; i < 4; i++) {
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lengths.add(rndm.nextInt(150));
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}
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StringBuilder sb = new StringBuilder();
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for (int i = 0; i < 100; i++) {
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for (int j = 0; j < whiteSpace.length; j++) {
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for (int k = 0; k < wordWrap.length; k++) {
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for (Integer len : lengths) {
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createCombinationTest(sb, i, whiteSpace[j], wordWrap[k], all, rndm, len);
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}
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}
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}
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}
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runFuzzTest(sb.toString(), false);
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runFuzzTest(sb.toString(), true);
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}
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// TODO:
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// + More form controls.
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// + Custom meta info.

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