Handle throwable with null message in REPL

appinventor/buildserver/src/com/google/appinventor/buildserver/resources/runtime.scm

@@ -413,13 +413,10 @@
 ;; Commented out -- we only send reports from the setting menu choice
 ;;         (com.google.appinventor.components.runtime.ReplApplication:reportError ex)
          (if isrepl
-             (when ((this):toastAllowed)
-                   (let ((message (if (instance? ex java.lang.Error) (ex:toString) (ex:getMessage))))
-                     (send-error message)
-                     ((android.widget.Toast:makeText (this) message 5):show)))
-
              (com.google.appinventor.components.runtime.util.RuntimeErrorAlert:alert
               (this)
+              (this):toastAllowed
+              (this):toastAllowed
               (ex:getMessage)
               (if (instance? ex YailRuntimeError) ((as YailRuntimeError ex):getErrorType) "Runtime Error")
               "End Application")))

appinventor/components/src/com/google/appinventor/components/runtime/util/AssetFetcher.java

@@ -146,18 +146,17 @@ private static File getFile(final String fileName, String cookieValue, String as
     Form form = Form.getActiveForm();
     if (depth > 1) {
       synchronized (semaphore) { // We are protecting the inError variable
-        if (inError) {
-          return null;
-        } else {
+        if (!inError) {
           inError = true;
           form.runOnUiThread(new Runnable() {
-              public void run() {
-                RuntimeErrorAlert.alert(Form.getActiveForm(), "Unable to load file: " + fileName,
+            public void run() {
+              RuntimeErrorAlert.alert(Form.getActiveForm(), false, true,
+                  "Unable to load file: " + fileName,
                   "Error!", "End Application");
-              }
-            });
-          return null;
+            }
+          });
         }
+        return null;
       }
     }
 

appinventor/components/src/com/google/appinventor/components/runtime/util/RuntimeErrorAlert.java

@@ -11,6 +11,7 @@
 import android.content.Context;
 import android.content.DialogInterface;
 import android.util.Log;
+import android.widget.Toast;
 
 /**
  * Shows a runtime error alert with a single button.  Pressing the button will
@@ -19,22 +20,33 @@
  * @author [email protected] (Hal Abelson)
  */
 public final class RuntimeErrorAlert {
+
+  private static final String TAG = "RuntimeErrorAlert";
+
   public static void alert(final Object context,
-      final String message, final String title,final String buttonText) {
-    Log.i("RuntimeErrorAlert", "in alert");
+                           boolean sendError,
+                           boolean toastAllowed,
+                           String message,
+                           String title,
+                           String buttonText) {
+    Log.e(TAG, "alert(" + message + ", " + title + ", " + buttonText);
+    if (message == null) {
+      // do not pass null, or it will result in a crash
+      message = title + " <No error message>";
+    }
+    if (toastAllowed) {
+      Toast.makeText((Context) context, message, Toast.LENGTH_SHORT).show();
+    }
+    if (sendError) {
+      RetValManager.sendError(message);
+    }
     AlertDialog alertDialog = new AlertDialog.Builder((Context) context).create();
     alertDialog.setTitle(title);
     alertDialog.setMessage(message);
-    alertDialog.setButton(buttonText, new DialogInterface.OnClickListener() {
+    alertDialog.setButton(AlertDialog.BUTTON_POSITIVE, buttonText, new DialogInterface.OnClickListener() {
       public void onClick(DialogInterface dialog, int which) {
         ((Activity) context).finish();
       }});
-    if (message == null) {
-      // Avoid passing null to Log.e, which would cause a NullPointerException.
-      Log.e(RuntimeErrorAlert.class.getName(), "No error message available");
-    } else {
-      Log.e(RuntimeErrorAlert.class.getName(), message);
-    }
     alertDialog.show();
   }
 }