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        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - REGRESSION: Error's &quot;column&quot; property should not be readonly"
   href="https://bugs.webkit.org/show_bug.cgi?id=146047">146047</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>REGRESSION: Error's &quot;column&quot; property should not be readonly
          </td>
        </tr>

        <tr>
          <th>Classification</th>
          <td>Unclassified
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>WebKit
          </td>
        </tr>

        <tr>
          <th>Version</th>
          <td>528+ (Nightly build)
          </td>
        </tr>

        <tr>
          <th>Hardware</th>
          <td>Unspecified
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>Unspecified
          </td>
        </tr>

        <tr>
          <th>Status</th>
          <td>NEW
          </td>
        </tr>

        <tr>
          <th>Severity</th>
          <td>Normal
          </td>
        </tr>

        <tr>
          <th>Priority</th>
          <td>P2
          </td>
        </tr>

        <tr>
          <th>Component</th>
          <td>JavaScriptCore
          </td>
        </tr>

        <tr>
          <th>Assignee</th>
          <td>webkit-unassigned&#64;lists.webkit.org
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>joepeck&#64;webkit.org
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>mark.lam&#64;apple.com, webkit-bug-importer&#64;group.apple.com
          </td>
        </tr></table>
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        <pre>* SUMMARY
Error's &quot;column&quot; property should not be readonly. This used to work in Safari 8, but now fails in ToT WebKit.

* TEST
&lt;script&gt;
&quot;use strict&quot;;
var error = new Error('My Error Message');
error.lineNumber = 1;
error.column = 2; // Should not trigger a TypeError.
console.log(&quot;SUCCESS&quot;, error);
&lt;/script&gt;

* STEPS TO REPRODUCE
1. Open attached test case
  =&gt; get an error attempting to set error.column, used to work
  =&gt; [Error] TypeError: Attempted to assign to readonly property.

* NOTES
- Firefox and Chrome do not throw an error
- This is done in the Esprima JS Library, so there may also be other libraries that do this and expect it to work

* DESCRIPTORS
<span class="quote">&gt; Object.getOwnPropertyDescriptor(error, &quot;column&quot;)</span >
&lt; {value: 22, writable: false, enumerable: true, configurable: false} = $2
<span class="quote">&gt; Object.getOwnPropertyDescriptor(error, &quot;lineNumber&quot;)</span >
&lt; {value: 1, writable: true, enumerable: true, configurable: true} = $3</pre>
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