some more coverage

compiler/tests/org/jetbrains/jet/compiler/CompileEnvironmentTest.java

@@ -6,7 +6,14 @@ import junit.framework.TestCase;
 import org.jetbrains.jet.codegen.ClassFileFactory;
 import org.jetbrains.jet.parsing.JetParsingTest;
 
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
 import java.io.File;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.jar.JarEntry;
+import java.util.jar.JarInputStream;
 
 /**
  * @author yole
@@ -25,7 +32,7 @@ public class CompileEnvironmentTest extends TestCase {
         super.tearDown();
     }
 
-    public void testSmoke() {
+    public void testSmoke() throws IOException {
         final File activeRtJar = CompileEnvironment.findRtJar(true);
         environment.setJavaRuntime(activeRtJar);
         environment.initializeKotlinRuntime();
@@ -36,5 +43,23 @@ public class CompileEnvironmentTest extends TestCase {
         final ClassFileFactory factory = environment.compileModule(moduleBuilder, testDataDir);
         assertNotNull(factory);
         assertNotNull(factory.asBytes("Smoke/namespace.class"));
+
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        CompileEnvironment.writeToJar(factory, baos, null, false);
+        JarInputStream is = new JarInputStream(new ByteArrayInputStream(baos.toByteArray()));
+        final List<String> entries = listEntries(is);
+        assertTrue(entries.contains("Smoke/namespace.class"));
+    }
+
+    private List<String> listEntries(JarInputStream is) throws IOException {
+        List<String> entries = new ArrayList<String>();
+        while (true) {
+            final JarEntry jarEntry = is.getNextJarEntry();
+            if (jarEntry == null) {
+                break;
+            }
+            entries.add(jarEntry.getName());
+        }
+        return entries;
     }
 }