Add tests validating class file validity and message contents

Author: Col-E

src/test/java/software/coley/lljzip/PartParseTests.java

@@ -3,6 +3,8 @@
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.ValueSource;
+import org.objectweb.asm.ClassReader;
+import org.objectweb.asm.ClassWriter;
 import software.coley.lljzip.format.compression.ZipCompressions;
 import software.coley.lljzip.format.model.LocalFileHeader;
 import software.coley.lljzip.format.model.ZipArchive;
@@ -14,6 +16,7 @@
 import java.io.IOException;
 import java.nio.file.Path;
 import java.nio.file.Paths;
+import java.util.List;
 
 import static org.junit.jupiter.api.Assertions.*;
 
@@ -105,6 +108,35 @@ public void testConcatAndMerged(String name) {
 		}
 	}
 
+	@ParameterizedTest
+	@ValueSource(strings = {
+			"hello-concat.jar",
+			"hello-concat-junkheader.jar",
+			"hello-merged.jar",
+			"hello-merged-fake-empty.jar",
+			"hello-merged-junkheader.jar",
+			"hello-secret-0-length-locals.jar",
+			"hello-secret-junkheader.jar",
+			"hello-secret-trailing-slash.jar",
+			"hello-secret-trailing-slash-0-length-locals.jar",
+	})
+	public void testJvmCanRecoverData(String name) {
+		try {
+			Path path = Paths.get("src/test/resources/" + name);
+			ZipArchive zip = ZipIO.readJvm(path);
+			List<LocalFileHeader> localFiles = zip.getNameFilteredLocalFiles(n -> n.contains(".class"));
+			assertEquals(1, localFiles.size(), "More than 1 class");
+			byte[] decompressed = ByteDataUtil.toByteArray(ZipCompressions.decompress(localFiles.get(0)));
+			assertDoesNotThrow(() -> {
+				ClassWriter cw = new ClassWriter(0);
+				ClassReader cr = new ClassReader(decompressed);
+				cr.accept(cw, 0);
+			}, "Failed to read class, must have failed to decompress");
+		} catch (IOException ex) {
+			fail(ex);
+		}
+	}
+
 	@Test
 	public void testLocalHeaderDetectMismatch() {
 		Path path = Paths.get("src/test/resources/hello-secret-0-length-locals.jar");

src/test/java/software/coley/lljzip/PatchingTests.java

@@ -3,7 +3,6 @@
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.ValueSource;
-import software.coley.lljzip.format.model.LocalFileHeader;
 import software.coley.lljzip.format.model.ZipArchive;
 import software.coley.lljzip.format.transform.IdentityZipPartMapper;
 import software.coley.lljzip.format.transform.JvmClassDirectoryMapper;
@@ -59,7 +58,7 @@ public void testTrickJarPatched(String name) {
 			}
 
 			// Parse the zip with LL-Java zip, then write back using std java apis
-			// in order to create a std java complaint jar.
+			// in order to create a std java compliant jar.
 			ZipArchive zip = ZipIO.readJvm(path);
 			new ZipOutputStreamZipWriter().write(zip, baos);
 			byte[] fixed = baos.toByteArray();