test: added test for extracting zstd'd tarfiles

Author: stevebillings

src/main/java/com/synopsys/integration/blackduck/imageinspector/image/common/ImageLayerApplier.java

@@ -47,7 +47,6 @@ public void applyLayer(File destinationDir, final TypedArchiveFile layerTar) thr
         } else if (layerTar.getType().equals(ArchiveFileType.TAR_GZIPPED)) {
             filesToRemove = imageLayerArchiveExtractor.extractLayerGzipTarToDir(fileOperations, layerTar.getFile(), destinationDir);
         } else if (layerTar.getType().equals(ArchiveFileType.TAR_ZSTD)) {
-            //TODO- test this works
             filesToRemove = imageLayerArchiveExtractor.extractLayerZstdTarToDir(fileOperations, layerTar.getFile(), destinationDir);
         }
         for (final File fileToRemove : filesToRemove) {

src/test/java/com/synopsys/integration/blackduck/imageinspector/image/common/archive/ImageLayerArchiveExtractorTest.java

@@ -21,6 +21,8 @@ public class ImageLayerArchiveExtractorTest {
     @TempDir
     File tempDir;
 
+    // TODO next 3 tests could be parameterized
+
     @Test
     void test() throws IOException {
         ImageLayerArchiveExtractor imageLayerArchiveExtractor = new ImageLayerArchiveExtractor();
@@ -37,6 +39,38 @@ void test() throws IOException {
         assertTrue(extractedFiles.stream().findFirst().get().isDirectory());
     }
 
+    @Test
+    void testTarGz() throws IOException {
+        ImageLayerArchiveExtractor imageLayerArchiveExtractor = new ImageLayerArchiveExtractor();
+        FileOperations fileOperations = new FileOperations();
+        File tarFile = new File("src/test/resources/layers/targz/123456");
+        File outputDir = new File(tempDir, "output");
+
+        imageLayerArchiveExtractor.extractLayerGzipTarToDir(fileOperations, tarFile, outputDir);
+
+        List<File> extractedFiles = Arrays.asList(outputDir.listFiles());
+        assertEquals(2, extractedFiles.size());
+        assertTrue(extractedFiles.stream().map(File::getName).filter(name -> name.equals("omit")).findAny().isPresent());
+        assertTrue(extractedFiles.stream().map(File::getName).filter(name -> name.equals("regular")).findAny().isPresent());
+        assertTrue(extractedFiles.stream().findFirst().get().isDirectory());
+    }
+
+    @Test
+    void testTarZstd() throws IOException {
+        ImageLayerArchiveExtractor imageLayerArchiveExtractor = new ImageLayerArchiveExtractor();
+        FileOperations fileOperations = new FileOperations();
+        File tarFile = new File("src/test/resources/layers/zstd/123456");
+        File outputDir = new File(tempDir, "output");
+
+        imageLayerArchiveExtractor.extractLayerZstdTarToDir(fileOperations, tarFile, outputDir);
+
+        List<File> extractedFiles = Arrays.asList(outputDir.listFiles());
+        assertEquals(2, extractedFiles.size());
+        assertTrue(extractedFiles.stream().map(File::getName).filter(name -> name.equals("omit")).findAny().isPresent());
+        assertTrue(extractedFiles.stream().map(File::getName).filter(name -> name.equals("regular")).findAny().isPresent());
+        assertTrue(extractedFiles.stream().findFirst().get().isDirectory());
+    }
+
     @Test
     public void testOpaqueDir() throws IOException {
         final File tarFile = new File("src/test/resources/layers/whiteoutOpaqueDir/layer.tar");