/*
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.devtools.j2objc.ast;

/**
 * Wraps an assertion error with information about the node where the error occurred.
 */
public class TreeVisitorError extends AssertionError {

  TreeVisitorError(Throwable original, TreeNode node) {
    super(constructMessage(original, node), original.getCause());
    setStackTrace(original.getStackTrace());
    for (Throwable t : original.getSuppressed()) {
      addSuppressed(t);
    }
  }

  private static String constructMessage(Throwable original, TreeNode node) {
    CompilationUnit unit = TreeUtil.getCompilationUnit(node);
    String msg = original.getMessage();
    if (msg == null || msg.isEmpty()) {
      msg = original.getClass().getSimpleName();
    }
    if (unit == null) {
      return msg;
    }
    return String.format(
        "%s:%s: %s", unit.getSourceFilePath(), node.getLineNumber(), msg);
  }
}

@@ -1151,179 +1151,82 @@
 ing 
-msg = original.getMessage();%0A    if (msg == null %7C%7C msg.isEmpty()) %7B%0A      msg = original.getClass().getSimpleName();%0A    %7D%0A    if (unit == null) %7B%0A      return msg;%0A    %7D
+sourceFile = unit != null ? unit.getSourceFilePath() : %22%3Cunknown source%3E%22;
 %0A   
@@ -1251,17 +1251,8 @@
 mat(
-%0A        
 %22%25s:
@@ -1261,20 +1261,24 @@
 : %25s
-%22, unit.getS
+: %25s%22,%0A        s
 ourc
@@ -1282,22 +1282,16 @@
 urceFile
-Path()
 , node.g
@@ -1310,11 +1310,74 @@
 (), 
-msg
+original.getClass().getSimpleName(),%0A        original.getMessage()
 );%0A 

Update the TreeVisitorError message to always include the type of the original exception. Sometimes the message alone isn't meaningfull without knowing the exception type. For example, a "-1" message isn't helpful without knowing that it was an ArrayIndexOutOfBoundsException.