src/test/java/com/google/devtools/build/android/dexer/DexFileMergerTest.java - bazel - Git at Google

 // Copyright 2017 The Bazel Authors. All rights reserved.
 //
 // Licensed 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 com.google.devtools.build.android.dexer;

 import static com.google.common.truth.Truth.assertThat;
 import static com.google.common.truth.Truth.assertWithMessage;
 import static java.nio.charset.StandardCharsets.UTF_8;
 import static org.junit.Assert.fail;

 import com.android.dex.ClassDef;
 import com.android.dex.Dex;
 import com.android.dx.command.dexer.DxContext;
 import com.android.dx.dex.code.PositionList;
 import com.google.common.base.Function;
 import com.google.common.base.Predicates;
 import com.google.common.collect.HashMultimap;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Iterators;
 import com.google.common.collect.Multimap;
 import com.google.common.collect.SetMultimap;
 import com.google.common.collect.Sets;
 import com.google.devtools.build.runfiles.Runfiles;
 import java.io.IOException;
 import java.nio.file.FileSystems;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.Enumeration;
 import java.util.HashSet;
 import java.util.Set;
 import java.util.zip.ZipEntry;
 import java.util.zip.ZipFile;
 import javax.annotation.Nullable;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.JUnit4;

 /** Tests for {@link DexFileMerger}. */
 @RunWith(JUnit4.class)
 public class DexFileMergerTest {

   private static final Path INPUT_JAR;
   private static final Path INPUT_JAR2;
   private static final Path MAIN_DEX_LIST_FILE;
   static final String DEX_PREFIX = "classes";

   static {
     try {
       Runfiles runfiles = Runfiles.create();

       INPUT_JAR = Paths.get(runfiles.rlocation(System.getProperty("testinputjar")));
       INPUT_JAR2 = Paths.get(runfiles.rlocation(System.getProperty("testinputjar2")));
       MAIN_DEX_LIST_FILE = Paths.get(runfiles.rlocation(System.getProperty("testmaindexlist")));
     } catch (Exception e) {
       throw new ExceptionInInitializerError(e);
     }
   }

   /** Exercises DexFileMerger to write a single .dex file. */
   @Test
   public void testMergeDexArchive_singleOutputDex() throws Exception {
     Path dexArchive = buildDexArchive();
     Path outputArchive = runDexFileMerger(dexArchive, 256 * 256, "from_dex_archive.dex.zip");

     int expectedClassCount = matchingFileCount(dexArchive, ".*\\.class.dex$");
     assertSingleDexOutput(expectedClassCount, outputArchive, "classes.dex");
   }

   @Test
   public void testMergeDexArchive_duplicateInputDeduped() throws Exception {
     Path dexArchive = buildDexArchive();
     Path outputArchive = runDexFileMerger(
         256 * 256,
         /*forceJumbo=*/ false,
         "duplicate.dex.zip",
         MultidexStrategy.MINIMAL,
         /*mainDexList=*/ null,
         /*minimalMainDex=*/ false,
         DEX_PREFIX,
         dexArchive,
         dexArchive);  // input Jar twice to induce duplicates

     int expectedClassCount = matchingFileCount(dexArchive, ".*\\.class.dex$");
     assertSingleDexOutput(expectedClassCount, outputArchive, "classes.dex");
   }

   /** Similar to {@link #testMergeDexArchive_singleOutputDex} but uses --multidex=given_shard. */
   @Test
   public void testMergeDexArchive_givenShard() throws Exception {
     Path dexArchive = buildDexArchive(INPUT_JAR, "3.classes.jar");
     Path outputArchive =
         runDexFileMerger(
             256 * 256,
             /*forceJumbo=*/ false,
             "given_shard.dex.zip",
             MultidexStrategy.GIVEN_SHARD,
             /*mainDexList=*/ null,
             /*minimalMainDex=*/ false,
             DEX_PREFIX,
             dexArchive);

     int expectedClassCount = matchingFileCount(dexArchive, ".*\\.class.dex$");
     assertSingleDexOutput(expectedClassCount, outputArchive, "classes3.dex");
   }

   /**
    * Similar to {@link #testMergeDexArchive_singleOutputDex} but different name for output dex file.
    */
   @Test
   public void testMergeDexArchive_singleOutputPrefixDex() throws Exception {
     Path dexArchive = buildDexArchive();
     Path outputArchive =
         runDexFileMerger(
             256 * 256,
             /*forceJumbo=*/ false,
             "prefix.dex.zip",
             MultidexStrategy.MINIMAL,
             /*mainDexList=*/ null,
             /*minimalMainDex=*/ false,
             "noname",
             dexArchive);

     int expectedClassCount = matchingFileCount(dexArchive, ".*\\.class.dex$");
     assertSingleDexOutput(expectedClassCount, outputArchive, "noname.dex");
   }

   /** Exercises DexFileMerger with two input archives. */
   @Test
   public void testMergeDexArchive_multipleInputs() throws Exception {
     Path dexArchive = buildDexArchive();
     Path dexArchive2 = buildDexArchive(INPUT_JAR2, "libtestdata.jar.dex.zip");
     Path outputArchive =
         runDexFileMerger(
             256 * 256,
             /*forceJumbo=*/ false,
             "multiple_inputs.dex.zip",
             MultidexStrategy.MINIMAL,
             /*mainDexList=*/ null,
             /*minimalMainDex=*/ false,
             DEX_PREFIX,
             dexArchive,
             dexArchive2);

     int expectedClassCount = matchingFileCount(dexArchive, ".*\\.class.dex$");
     expectedClassCount += matchingFileCount(dexArchive2, ".*\\.class.dex$");
     assertSingleDexOutput(expectedClassCount, outputArchive, "classes.dex");
   }

   /**
    * Similar to {@link #testMergeDexArchive_singleOutputDex} but forces multiple output dex files.
    */
   @Test
   public void testMergeDexArchive_multidex() throws Exception {
     Path dexArchive = buildDexArchive();
     Path outputArchive = runDexFileMerger(dexArchive, 200, "multidex_from_dex_archive.dex.zip");

     int expectedClassCount = matchingFileCount(dexArchive, ".*\\.class.dex$");
     assertMultidexOutput(expectedClassCount, outputArchive, ImmutableSet.<String>of());
   }

   @Test
   public void testMergeDexArchive_mainDexList() throws Exception {
     Path dexArchive = buildDexArchive();
     Path outputArchive =
         runDexFileMerger(
             200,
             /*forceJumbo=*/ false,
             "main_dex_list.dex.zip",
             MultidexStrategy.MINIMAL,
             MAIN_DEX_LIST_FILE,
             /*minimalMainDex=*/ false,
             DEX_PREFIX,
             dexArchive);

     int expectedClassCount = matchingFileCount(dexArchive, ".*\\.class.dex$");
     assertMainDexOutput(expectedClassCount, outputArchive, false);
   }

   @Test
   public void testMergeDexArchive_minimalMainDex() throws Exception {
     Path dexArchive = buildDexArchive();
     Path outputArchive =
         runDexFileMerger(
             256 * 256,
             /*forceJumbo=*/ false,
             "minimal_main_dex.dex.zip",
             MultidexStrategy.MINIMAL,
             MAIN_DEX_LIST_FILE,
             /*minimalMainDex=*/ true,
             DEX_PREFIX,
             dexArchive);

     int expectedClassCount = matchingFileCount(dexArchive, ".*\\.class.dex$");
     assertMainDexOutput(expectedClassCount, outputArchive, true);
   }

   @Test
   public void testMultidexOffWithMultidexFlags() throws Exception {
     Path dexArchive = buildDexArchive();
     try {
       runDexFileMerger(
           200,
           /*forceJumbo=*/ false,
           "classes.dex.zip",
           MultidexStrategy.OFF,
           /*mainDexList=*/ null,
           /*minimalMainDex=*/ true,
           DEX_PREFIX,
           dexArchive);
       fail("Expected DexFileMerger to fail");
     } catch (IllegalArgumentException e) {
       assertThat(e)
           .hasMessageThat()
           .isEqualTo(
               "--minimal-main-dex is only supported with multidex enabled, but mode is: OFF");
     }
     try {
       runDexFileMerger(
           200,
           /*forceJumbo=*/ false,
           "classes.dex.zip",
           MultidexStrategy.OFF,
           MAIN_DEX_LIST_FILE,
           /*minimalMainDex=*/ false,
           DEX_PREFIX,
           dexArchive);
       fail("Expected DexFileMerger to fail");
     } catch (IllegalArgumentException e) {
       assertThat(e)
           .hasMessageThat()
           .isEqualTo("--main-dex-list is only supported with multidex enabled, but mode is: OFF");
     }
   }

   /** Exercises --forceJumbo support. */
   @Test
   public void testMergeDexArchive_forceJumbo() throws Exception {
     Path dexArchive = buildDexArchive();
     Path outputArchive;
     try {
       outputArchive = runDexFileMerger(256 * 256, /*forceJumbo=*/ true, "from_dex_archive.dex.zip",
           MultidexStrategy.OFF, /*mainDexList=*/ null, /*minimalMainDex=*/ false, DEX_PREFIX,
           dexArchive);
     } catch (IllegalStateException e) {
       assertThat(e).hasMessageThat().isEqualTo("--forceJumbo flag not supported");
       System.err.println("Skipping this test due to missing --forceJumbo support in Android SDK.");
       e.printStackTrace();
       return;
     }

     int expectedClassCount = matchingFileCount(dexArchive, ".*\\.class.dex$");
     assertSingleDexOutput(expectedClassCount, outputArchive, "classes.dex");
   }

   private void assertSingleDexOutput(int expectedClassCount, Path outputArchive, String dexFileName)
       throws IOException {
     try (ZipFile output = new ZipFile(outputArchive.toFile())) {
       ZipEntry entry = Iterators.getOnlyElement(Iterators.forEnumeration(output.entries()));
       assertThat(entry.getName()).isEqualTo(dexFileName);
       Dex dex = new Dex(output.getInputStream(entry));
       assertThat(dex.classDefs()).hasSize(expectedClassCount);
     }
   }

   private Multimap<String, String> assertMultidexOutput(int expectedClassCount,
       Path outputArchive, Set<String> mainDexList) throws IOException {
     SetMultimap<String, String> dexFiles = HashMultimap.create();
     try (ZipFile output = new ZipFile(outputArchive.toFile())) {
       Enumeration<? extends ZipEntry> entries = output.entries();
       while (entries.hasMoreElements()) {
         ZipEntry entry = entries.nextElement();
         assertThat(entry.getName()).containsMatch("classes[2-9]?.dex");
         Dex dex = new Dex(output.getInputStream(entry));
         for (ClassDef clazz : dex.classDefs()) {
           dexFiles.put(entry.getName(),
               toSlashedClassName(dex.typeNames().get(clazz.getTypeIndex())));
         }
       }
     }
     assertThat(dexFiles.keySet().size()).isAtLeast(2);
     assertThat(dexFiles.size()).isAtLeast(1);
     assertThat(dexFiles).hasSize(expectedClassCount);
     for (int i = 0; i < dexFiles.keySet().size(); ++i) {
       assertThat(dexFiles).containsKey(expectedDexFileName(i));
     }
     for (int i = 1; i < dexFiles.keySet().size(); ++i) {
       Set<String> prev = dexFiles.get(expectedDexFileName(i - 1));
       if (i == 1) {
         prev = Sets.difference(prev, mainDexList);
       }
       Set<String> shard = dexFiles.get(expectedDexFileName(i));
       for (String c1 : prev) {
         for (String c2 : shard) {
           assertWithMessage(
                   c2
                       + " in shard "
                       + i
                       + " should compare as larger than "
                       + c1
                       + "; list of all shards for reference: "
                       + dexFiles)
               .that(ZipEntryComparator.compareClassNames(c2, c1))
               .isGreaterThan(0);
         }
       }
     }
     return dexFiles;
   }

   private static String expectedDexFileName(int i) {
     return DEX_PREFIX + (i == 0 ? "" : i + 1) + ".dex";
   }

   private void assertMainDexOutput(int expectedClassCount, Path outputArchive,
       boolean minimalMainDex) throws IOException {
     HashSet<String> mainDexList = new HashSet<>();
     for (String filename : Files.readAllLines(MAIN_DEX_LIST_FILE, UTF_8)) {
       mainDexList.add(
           filename.endsWith(".class") ? filename.substring(0, filename.length() - 6) : filename);
     }
     Multimap<String, String> dexFiles =
         assertMultidexOutput(expectedClassCount, outputArchive, mainDexList);
     assertThat(dexFiles.keySet().size()).isAtLeast(2);
     if (minimalMainDex) {
       assertThat(dexFiles.get("classes.dex")).containsExactlyElementsIn(mainDexList);
     } else {
       assertThat(dexFiles.get("classes.dex")).containsAtLeastElementsIn(mainDexList);
     }
   }

   /** Converts signature classes, eg., "Lpath/to/Class;", to regular names like "path/to/Class". */
   private static String toSlashedClassName(String signatureClassname) {
     return signatureClassname.substring(1, signatureClassname.length() - 1);
   }

   private int matchingFileCount(Path dexArchive, String filenameFilter) throws IOException {
     try (ZipFile input = new ZipFile(dexArchive.toFile())) {
       return Iterators.size(Iterators.filter(
           Iterators.transform(Iterators.forEnumeration(input.entries()), ZipEntryName.INSTANCE),
           Predicates.containsPattern(filenameFilter)));
     }
   }

   private Path runDexFileMerger(Path dexArchive, int maxNumberOfIdxPerDex, String outputBasename)
       throws IOException {
     return runDexFileMerger(
         maxNumberOfIdxPerDex,
         /*forceJumbo=*/ false,
         outputBasename,
         MultidexStrategy.MINIMAL,
         /*mainDexList=*/ null,
         /*minimalMainDex=*/ false,
         DEX_PREFIX,
         dexArchive);
   }

   private Path runDexFileMerger(
       int maxNumberOfIdxPerDex,
       boolean forceJumbo,
       String outputBasename,
       MultidexStrategy multidexMode,
       @Nullable Path mainDexList,
       boolean minimalMainDex,
       String dexPrefix,
       Path... dexArchives)
       throws IOException {
     DexFileMerger.Options options = new DexFileMerger.Options();
     options.inputArchives = ImmutableList.copyOf(dexArchives);
     options.outputArchive =
         FileSystems.getDefault().getPath(System.getenv("TEST_TMPDIR"), outputBasename);
     options.multidexMode = multidexMode;
     options.maxNumberOfIdxPerDex = maxNumberOfIdxPerDex;
     options.forceJumbo = forceJumbo;
     options.mainDexListFile = mainDexList;
     options.minimalMainDex = minimalMainDex;
     options.dexPrefix = dexPrefix;
     DexFileMerger.buildMergedDexFiles(options);
     assertThat(options.outputArchive.toFile().exists()).isTrue();
     return options.outputArchive;
   }

   private Path buildDexArchive() throws Exception {
     return buildDexArchive(INPUT_JAR, "libtests.dex.zip");
   }

   private Path buildDexArchive(Path inputJar, String outputZip) throws Exception {
     DexBuilder.Options options = new DexBuilder.Options();
     options.inputJar = inputJar;
     options.outputZip = FileSystems.getDefault().getPath(System.getenv("TEST_TMPDIR"), outputZip);
     options.maxThreads = 1;
     Dexing.DexingOptions dexingOptions = new Dexing.DexingOptions();
     dexingOptions.optimize = true;
     dexingOptions.positionInfo = PositionList.LINES;
     DexBuilder.buildDexArchive(options, new Dexing(new DxContext(), dexingOptions));
     return options.outputZip;
   }

   private enum ZipEntryName implements Function<ZipEntry, String> {
     INSTANCE;
     @Override
     public String apply(ZipEntry input) {
       return input.getName();
     }
   }
 }
	// Copyright 2017 The Bazel Authors. All rights reserved.
	//
	// Licensed 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 com.google.devtools.build.android.dexer;

	import static com.google.common.truth.Truth.assertThat;
	import static com.google.common.truth.Truth.assertWithMessage;
	import static java.nio.charset.StandardCharsets.UTF_8;
	import static org.junit.Assert.fail;

	import com.android.dex.ClassDef;
	import com.android.dex.Dex;
	import com.android.dx.command.dexer.DxContext;
	import com.android.dx.dex.code.PositionList;
	import com.google.common.base.Function;
	import com.google.common.base.Predicates;
	import com.google.common.collect.HashMultimap;
	import com.google.common.collect.ImmutableList;
	import com.google.common.collect.ImmutableSet;
	import com.google.common.collect.Iterators;
	import com.google.common.collect.Multimap;
	import com.google.common.collect.SetMultimap;
	import com.google.common.collect.Sets;
	import com.google.devtools.build.runfiles.Runfiles;
	import java.io.IOException;
	import java.nio.file.FileSystems;
	import java.nio.file.Files;
	import java.nio.file.Path;
	import java.nio.file.Paths;
	import java.util.Enumeration;
	import java.util.HashSet;
	import java.util.Set;
	import java.util.zip.ZipEntry;
	import java.util.zip.ZipFile;
	import javax.annotation.Nullable;
	import org.junit.Test;
	import org.junit.runner.RunWith;
	import org.junit.runners.JUnit4;

	/** Tests for {@link DexFileMerger}. */
	@RunWith(JUnit4.class)
	public class DexFileMergerTest {

	private static final Path INPUT_JAR;
	private static final Path INPUT_JAR2;
	private static final Path MAIN_DEX_LIST_FILE;
	static final String DEX_PREFIX = "classes";

	static {
	try {
	Runfiles runfiles = Runfiles.create();

	INPUT_JAR = Paths.get(runfiles.rlocation(System.getProperty("testinputjar")));
	INPUT_JAR2 = Paths.get(runfiles.rlocation(System.getProperty("testinputjar2")));
	MAIN_DEX_LIST_FILE = Paths.get(runfiles.rlocation(System.getProperty("testmaindexlist")));
	} catch (Exception e) {
	throw new ExceptionInInitializerError(e);
	}
	}

	/** Exercises DexFileMerger to write a single .dex file. */
	@Test
	public void testMergeDexArchive_singleOutputDex() throws Exception {
	Path dexArchive = buildDexArchive();
	Path outputArchive = runDexFileMerger(dexArchive, 256 * 256, "from_dex_archive.dex.zip");

	int expectedClassCount = matchingFileCount(dexArchive, ".*\\.class.dex$");
	assertSingleDexOutput(expectedClassCount, outputArchive, "classes.dex");
	}

	@Test
	public void testMergeDexArchive_duplicateInputDeduped() throws Exception {
	Path dexArchive = buildDexArchive();
	Path outputArchive = runDexFileMerger(
	256 * 256,
	/forceJumbo=/ false,
	"duplicate.dex.zip",
	MultidexStrategy.MINIMAL,
	/mainDexList=/ null,
	/minimalMainDex=/ false,
	DEX_PREFIX,
	dexArchive,
	dexArchive); // input Jar twice to induce duplicates

	int expectedClassCount = matchingFileCount(dexArchive, ".*\\.class.dex$");
	assertSingleDexOutput(expectedClassCount, outputArchive, "classes.dex");
	}

	/** Similar to {@link #testMergeDexArchive_singleOutputDex} but uses --multidex=given_shard. */
	@Test
	public void testMergeDexArchive_givenShard() throws Exception {
	Path dexArchive = buildDexArchive(INPUT_JAR, "3.classes.jar");
	Path outputArchive =
	runDexFileMerger(
	256 * 256,
	/forceJumbo=/ false,
	"given_shard.dex.zip",
	MultidexStrategy.GIVEN_SHARD,
	/mainDexList=/ null,
	/minimalMainDex=/ false,
	DEX_PREFIX,
	dexArchive);

	int expectedClassCount = matchingFileCount(dexArchive, ".*\\.class.dex$");
	assertSingleDexOutput(expectedClassCount, outputArchive, "classes3.dex");
	}

	/**
	* Similar to {@link #testMergeDexArchive_singleOutputDex} but different name for output dex file.
	*/
	@Test
	public void testMergeDexArchive_singleOutputPrefixDex() throws Exception {
	Path dexArchive = buildDexArchive();
	Path outputArchive =
	runDexFileMerger(
	256 * 256,
	/forceJumbo=/ false,
	"prefix.dex.zip",
	MultidexStrategy.MINIMAL,
	/mainDexList=/ null,
	/minimalMainDex=/ false,
	"noname",
	dexArchive);

	int expectedClassCount = matchingFileCount(dexArchive, ".*\\.class.dex$");
	assertSingleDexOutput(expectedClassCount, outputArchive, "noname.dex");
	}

	/** Exercises DexFileMerger with two input archives. */
	@Test
	public void testMergeDexArchive_multipleInputs() throws Exception {
	Path dexArchive = buildDexArchive();
	Path dexArchive2 = buildDexArchive(INPUT_JAR2, "libtestdata.jar.dex.zip");
	Path outputArchive =
	runDexFileMerger(
	256 * 256,
	/forceJumbo=/ false,
	"multiple_inputs.dex.zip",
	MultidexStrategy.MINIMAL,
	/mainDexList=/ null,
	/minimalMainDex=/ false,
	DEX_PREFIX,
	dexArchive,
	dexArchive2);

	int expectedClassCount = matchingFileCount(dexArchive, ".*\\.class.dex$");
	expectedClassCount += matchingFileCount(dexArchive2, ".*\\.class.dex$");
	assertSingleDexOutput(expectedClassCount, outputArchive, "classes.dex");
	}

	/**
	* Similar to {@link #testMergeDexArchive_singleOutputDex} but forces multiple output dex files.
	*/
	@Test
	public void testMergeDexArchive_multidex() throws Exception {
	Path dexArchive = buildDexArchive();
	Path outputArchive = runDexFileMerger(dexArchive, 200, "multidex_from_dex_archive.dex.zip");

	int expectedClassCount = matchingFileCount(dexArchive, ".*\\.class.dex$");
	assertMultidexOutput(expectedClassCount, outputArchive, ImmutableSet.<String>of());
	}

	@Test
	public void testMergeDexArchive_mainDexList() throws Exception {
	Path dexArchive = buildDexArchive();
	Path outputArchive =
	runDexFileMerger(
	200,
	/forceJumbo=/ false,
	"main_dex_list.dex.zip",
	MultidexStrategy.MINIMAL,
	MAIN_DEX_LIST_FILE,
	/minimalMainDex=/ false,
	DEX_PREFIX,
	dexArchive);

	int expectedClassCount = matchingFileCount(dexArchive, ".*\\.class.dex$");
	assertMainDexOutput(expectedClassCount, outputArchive, false);
	}

	@Test
	public void testMergeDexArchive_minimalMainDex() throws Exception {
	Path dexArchive = buildDexArchive();
	Path outputArchive =
	runDexFileMerger(
	256 * 256,
	/forceJumbo=/ false,
	"minimal_main_dex.dex.zip",
	MultidexStrategy.MINIMAL,
	MAIN_DEX_LIST_FILE,
	/minimalMainDex=/ true,
	DEX_PREFIX,
	dexArchive);

	int expectedClassCount = matchingFileCount(dexArchive, ".*\\.class.dex$");
	assertMainDexOutput(expectedClassCount, outputArchive, true);
	}

	@Test
	public void testMultidexOffWithMultidexFlags() throws Exception {
	Path dexArchive = buildDexArchive();
	try {
	runDexFileMerger(
	200,
	/forceJumbo=/ false,
	"classes.dex.zip",
	MultidexStrategy.OFF,
	/mainDexList=/ null,
	/minimalMainDex=/ true,
	DEX_PREFIX,
	dexArchive);
	fail("Expected DexFileMerger to fail");
	} catch (IllegalArgumentException e) {
	assertThat(e)
	.hasMessageThat()
	.isEqualTo(
	"--minimal-main-dex is only supported with multidex enabled, but mode is: OFF");
	}
	try {
	runDexFileMerger(
	200,
	/forceJumbo=/ false,
	"classes.dex.zip",
	MultidexStrategy.OFF,
	MAIN_DEX_LIST_FILE,
	/minimalMainDex=/ false,
	DEX_PREFIX,
	dexArchive);
	fail("Expected DexFileMerger to fail");
	} catch (IllegalArgumentException e) {
	assertThat(e)
	.hasMessageThat()
	.isEqualTo("--main-dex-list is only supported with multidex enabled, but mode is: OFF");
	}
	}

	/** Exercises --forceJumbo support. */
	@Test
	public void testMergeDexArchive_forceJumbo() throws Exception {
	Path dexArchive = buildDexArchive();
	Path outputArchive;
	try {
	outputArchive = runDexFileMerger(256 * 256, /forceJumbo=/ true, "from_dex_archive.dex.zip",
	MultidexStrategy.OFF, /mainDexList=/ null, /minimalMainDex=/ false, DEX_PREFIX,
	dexArchive);
	} catch (IllegalStateException e) {
	assertThat(e).hasMessageThat().isEqualTo("--forceJumbo flag not supported");
	System.err.println("Skipping this test due to missing --forceJumbo support in Android SDK.");
	e.printStackTrace();
	return;
	}

	int expectedClassCount = matchingFileCount(dexArchive, ".*\\.class.dex$");
	assertSingleDexOutput(expectedClassCount, outputArchive, "classes.dex");
	}

	private void assertSingleDexOutput(int expectedClassCount, Path outputArchive, String dexFileName)
	throws IOException {
	try (ZipFile output = new ZipFile(outputArchive.toFile())) {
	ZipEntry entry = Iterators.getOnlyElement(Iterators.forEnumeration(output.entries()));
	assertThat(entry.getName()).isEqualTo(dexFileName);
	Dex dex = new Dex(output.getInputStream(entry));
	assertThat(dex.classDefs()).hasSize(expectedClassCount);
	}
	}

	private Multimap<String, String> assertMultidexOutput(int expectedClassCount,
	Path outputArchive, Set<String> mainDexList) throws IOException {
	SetMultimap<String, String> dexFiles = HashMultimap.create();
	try (ZipFile output = new ZipFile(outputArchive.toFile())) {
	Enumeration<? extends ZipEntry> entries = output.entries();
	while (entries.hasMoreElements()) {
	ZipEntry entry = entries.nextElement();
	assertThat(entry.getName()).containsMatch("classes[2-9]?.dex");
	Dex dex = new Dex(output.getInputStream(entry));
	for (ClassDef clazz : dex.classDefs()) {
	dexFiles.put(entry.getName(),
	toSlashedClassName(dex.typeNames().get(clazz.getTypeIndex())));
	}
	}
	}
	assertThat(dexFiles.keySet().size()).isAtLeast(2);
	assertThat(dexFiles.size()).isAtLeast(1);
	assertThat(dexFiles).hasSize(expectedClassCount);
	for (int i = 0; i < dexFiles.keySet().size(); ++i) {
	assertThat(dexFiles).containsKey(expectedDexFileName(i));
	}
	for (int i = 1; i < dexFiles.keySet().size(); ++i) {
	Set<String> prev = dexFiles.get(expectedDexFileName(i - 1));
	if (i == 1) {
	prev = Sets.difference(prev, mainDexList);
	}
	Set<String> shard = dexFiles.get(expectedDexFileName(i));
	for (String c1 : prev) {
	for (String c2 : shard) {
	assertWithMessage(
	c2
	+ " in shard "
	+ i
	+ " should compare as larger than "
	+ c1
	+ "; list of all shards for reference: "
	+ dexFiles)
	.that(ZipEntryComparator.compareClassNames(c2, c1))
	.isGreaterThan(0);
	}
	}
	}
	return dexFiles;
	}

	private static String expectedDexFileName(int i) {
	return DEX_PREFIX + (i == 0 ? "" : i + 1) + ".dex";
	}

	private void assertMainDexOutput(int expectedClassCount, Path outputArchive,
	boolean minimalMainDex) throws IOException {
	HashSet<String> mainDexList = new HashSet<>();
	for (String filename : Files.readAllLines(MAIN_DEX_LIST_FILE, UTF_8)) {
	mainDexList.add(
	filename.endsWith(".class") ? filename.substring(0, filename.length() - 6) : filename);
	}
	Multimap<String, String> dexFiles =
	assertMultidexOutput(expectedClassCount, outputArchive, mainDexList);
	assertThat(dexFiles.keySet().size()).isAtLeast(2);
	if (minimalMainDex) {
	assertThat(dexFiles.get("classes.dex")).containsExactlyElementsIn(mainDexList);
	} else {
	assertThat(dexFiles.get("classes.dex")).containsAtLeastElementsIn(mainDexList);
	}
	}

	/** Converts signature classes, eg., "Lpath/to/Class;", to regular names like "path/to/Class". */
	private static String toSlashedClassName(String signatureClassname) {
	return signatureClassname.substring(1, signatureClassname.length() - 1);
	}

	private int matchingFileCount(Path dexArchive, String filenameFilter) throws IOException {
	try (ZipFile input = new ZipFile(dexArchive.toFile())) {
	return Iterators.size(Iterators.filter(
	Iterators.transform(Iterators.forEnumeration(input.entries()), ZipEntryName.INSTANCE),
	Predicates.containsPattern(filenameFilter)));
	}
	}

	private Path runDexFileMerger(Path dexArchive, int maxNumberOfIdxPerDex, String outputBasename)
	throws IOException {
	return runDexFileMerger(
	maxNumberOfIdxPerDex,
	/forceJumbo=/ false,
	outputBasename,
	MultidexStrategy.MINIMAL,
	/mainDexList=/ null,
	/minimalMainDex=/ false,
	DEX_PREFIX,
	dexArchive);
	}

	private Path runDexFileMerger(
	int maxNumberOfIdxPerDex,
	boolean forceJumbo,
	String outputBasename,
	MultidexStrategy multidexMode,
	@Nullable Path mainDexList,
	boolean minimalMainDex,
	String dexPrefix,
	Path... dexArchives)
	throws IOException {
	DexFileMerger.Options options = new DexFileMerger.Options();
	options.inputArchives = ImmutableList.copyOf(dexArchives);
	options.outputArchive =
	FileSystems.getDefault().getPath(System.getenv("TEST_TMPDIR"), outputBasename);
	options.multidexMode = multidexMode;
	options.maxNumberOfIdxPerDex = maxNumberOfIdxPerDex;
	options.forceJumbo = forceJumbo;
	options.mainDexListFile = mainDexList;
	options.minimalMainDex = minimalMainDex;
	options.dexPrefix = dexPrefix;
	DexFileMerger.buildMergedDexFiles(options);
	assertThat(options.outputArchive.toFile().exists()).isTrue();
	return options.outputArchive;
	}

	private Path buildDexArchive() throws Exception {
	return buildDexArchive(INPUT_JAR, "libtests.dex.zip");
	}

	private Path buildDexArchive(Path inputJar, String outputZip) throws Exception {
	DexBuilder.Options options = new DexBuilder.Options();
	options.inputJar = inputJar;
	options.outputZip = FileSystems.getDefault().getPath(System.getenv("TEST_TMPDIR"), outputZip);
	options.maxThreads = 1;
	Dexing.DexingOptions dexingOptions = new Dexing.DexingOptions();
	dexingOptions.optimize = true;
	dexingOptions.positionInfo = PositionList.LINES;
	DexBuilder.buildDexArchive(options, new Dexing(new DxContext(), dexingOptions));
	return options.outputZip;
	}

	private enum ZipEntryName implements Function<ZipEntry, String> {
	INSTANCE;
	@Override
	public String apply(ZipEntry input) {
	return input.getName();
	}
	}
	}