Add unit tests

- add APK file containing a simple app that tries to use coroutines every 2 seconds, and would fail with earlier versions of APKTool
- add unit test for decoding the app

brut.apktool/apktool-lib/src/main/java/brut/androlib/Androlib.java

@@ -568,6 +568,7 @@ public class Androlib {
         buildLibrary(appDir, "lib");
         buildLibrary(appDir, "libs");
         buildLibrary(appDir, "kotlin");
+        buildLibrary(appDir, "META-INF/services");
     }
 
     public void buildLibrary(File appDir, String folder) throws AndrolibException {
@@ -756,6 +757,7 @@ public class Androlib {
         return ! stored.exists() || BrutIO.recursiveModifiedTime(working) > BrutIO .recursiveModifiedTime(stored);
     }
 
+
     private boolean isFile(File working) {
         return working.exists();
     }

brut.apktool/apktool-lib/src/test/java/brut/androlib/decode/DecodeKotlinCoroutinesTest.java

@@ -0,0 +1,107 @@
+/**
+ * Copyright (C) 2018 Ryszard Wiśniewski <brut.alll@gmail.com>
+ * Copyright (C) 2018 Connor Tumbleson <connor.tumbleson@gmail.com>
+ * <p>
+ * 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
+ * <p>
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * <p>
+ * 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 brut.androlib.decode;
+
+import org.junit.AfterClass;
+import org.junit.Before;
+import org.junit.BeforeClass;
+import org.junit.Ignore;
+import org.junit.Test;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+
+import brut.androlib.Androlib;
+import brut.androlib.AndrolibException;
+import brut.androlib.ApkDecoder;
+import brut.androlib.BaseTest;
+import brut.androlib.TestUtils;
+import brut.common.BrutException;
+import brut.directory.DirectoryException;
+import brut.directory.ExtFile;
+import brut.util.OS;
+
+import static org.junit.Assert.assertTrue;
+
+/**
+ * @author Adib Faramarzi <adibfara@gmail.com>
+ */
+public class DecodeKotlinCoroutinesTest extends BaseTest {
+    private static String apk = "test-kotlin-coroutines.apk";
+    @BeforeClass
+    public static void beforeClass() throws Exception {
+        TestUtils.cleanFrameworkFile();
+        sTmpDir = new ExtFile(OS.createTempDirectory());
+        TestUtils.copyResourceDir(DecodeKotlinCoroutinesTest.class, "decode/kotlin-coroutines/", sTmpDir);
+    }
+
+    @AfterClass
+    public static void afterClass() throws BrutException {
+        OS.rmdir(sTmpDir);
+    }
+
+
+    @Test
+    public void kotlinCoroutinesDecodeTest() throws IOException, AndrolibException, DirectoryException {
+
+        // decode kotlin coroutines
+        ApkDecoder apkDecoder = new ApkDecoder(new File(sTmpDir + File.separator + apk));
+        apkDecoder.setOutDir(new File(sTmpDir + File.separator + apk + ".out"));
+        apkDecoder.setForceDelete(true);
+        apkDecoder.decode();
+        File coroutinesExceptionHandler = new File(sTmpDir + File.separator + apk + ".out"+File.separator + "META-INF" + File.separator + "services", "kotlinx.coroutines.CoroutineExceptionHandler");
+        File coroutinenMainDispatcherHandler = new File(sTmpDir + File.separator + apk + ".out"+File.separator + "META-INF" + File.separator + "services", "kotlinx.coroutines.internal.MainDispatcherFactory");
+
+        assert (coroutinesExceptionHandler.exists());
+        assert (coroutinenMainDispatcherHandler.exists());
+    }
+
+    @Test
+    public void kotlinCoroutinesEncodeAfterDecodeTest() throws IOException, BrutException {
+
+        // decode kotlin coroutines
+        ApkDecoder apkDecoder = new ApkDecoder(new File(sTmpDir + File.separator + apk));
+        apkDecoder.setOutDir(new File(sTmpDir + File.separator + apk + ".out"));
+        apkDecoder.setForceDelete(true);
+        apkDecoder.decode();
+
+        // build kotlin coroutines
+        ExtFile testApk = new ExtFile(sTmpDir, apk + ".out");
+        new Androlib().build(testApk, null);
+        String newApk = apk + ".out" + File.separator + "dist" + File.separator + apk;
+        assertTrue(fileExists(newApk));
+
+        // decode kotlin coroutines again
+        apkDecoder = new ApkDecoder(new File(sTmpDir + File.separator + newApk));
+        apkDecoder.setOutDir(new File(sTmpDir + File.separator + apk + ".out.two"));
+        apkDecoder.setForceDelete(true);
+        apkDecoder.decode();
+
+        Files.readAllBytes(Paths.get(sTmpDir + File.separator + apk + ".out.two" + File.separator + "AndroidManifest.xml"));
+        File coroutinesExceptionHandler = new File(sTmpDir + File.separator + apk + ".out.two" + File.separator + "META-INF" + File.separator + "services", "kotlinx.coroutines.CoroutineExceptionHandler");
+        File coroutinenMainDispatcherHandler = new File(sTmpDir + File.separator + apk + ".out.two" + File.separator + "META-INF" + File.separator + "services", "kotlinx.coroutines.internal.MainDispatcherFactory");
+
+        assert (coroutinesExceptionHandler.exists());
+        assert (coroutinenMainDispatcherHandler.exists());
+    }
+
+    private boolean fileExists(String filepath) {
+        return Files.exists(Paths.get(sTmpDir.getAbsolutePath() + File.separator + filepath));
+    }
+}