Making compiler exit codes type safe. Fixes the problem with wrong command-line argument usage being missed by the IDE

idea/src/org/jetbrains/jet/plugin/compiler/JetCompiler.java

@@ -274,8 +274,10 @@ public class JetCompiler implements TranslatingCompiler {
             context.addMessage(INFORMATION, "Invoking in-process compiler " + compilerClassName + " with arguments " + Arrays.asList(arguments), "", -1, -1);
             
             Object rc = exec.invoke(kompiler.newInstance(), out, arguments);
-            if (rc instanceof Integer) {
-                return ((Integer) rc).intValue();
+            // exec() returns a KotlinCompiler.ExitCode object, that class is not accessible here,
+            // so we take it's contents through reflection
+            if ("org.jetbrains.jet.cli.KotlinCompiler.ExitCode".equals(rc.getClass().getCanonicalName())) {
+                return (Integer) rc.getClass().getMethod("getCode").invoke(rc);
             }
             else {
                 throw new IllegalStateException("Unexpected return: " + rc);

idea/tests/org/jetbrains/jet/plugin/libraries/LibrariesTest.java

@@ -150,8 +150,8 @@ public class LibrariesTest extends PlatformTestCase {
     protected void setUp() throws Exception {
         super.setUp();
         String libraryDir = FileUtil.getTempDirectory();
-        int compilerExec = new KotlinCompiler().exec("-src", TEST_DATA_PATH + "/library", "-output", libraryDir);
-        assertEquals(0, compilerExec);
+        KotlinCompiler.ExitCode compilerExec = new KotlinCompiler().exec("-src", TEST_DATA_PATH + "/library", "-output", libraryDir);
+        assertEquals(KotlinCompiler.ExitCode.OK, compilerExec);
         myLibraryDir = LocalFileSystem.getInstance().findFileByPath(libraryDir);
         assertNotNull(myLibraryDir);
 
@@ -168,4 +168,4 @@ public class LibrariesTest extends PlatformTestCase {
             }
         });
     }
-}
+}