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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - Unexpected exception assigning to this._property inside arrow function"
href="https://bugs.webkit.org/show_bug.cgi?id=152028">152028</a>
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<th>Summary</th>
<td>Unexpected exception assigning to this._property inside arrow function
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<th>Classification</th>
<td>Unclassified
</td>
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<th>Product</th>
<td>WebKit
</td>
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<th>Version</th>
<td>WebKit Nightly Build
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<th>Hardware</th>
<td>Unspecified
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<th>OS</th>
<td>Unspecified
</td>
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<th>Status</th>
<td>NEW
</td>
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<th>Severity</th>
<td>Normal
</td>
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<th>Priority</th>
<td>P2
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<th>Component</th>
<td>JavaScriptCore
</td>
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<th>Assignee</th>
<td>webkit-unassigned@lists.webkit.org
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<th>Reporter</th>
<td>joepeck@webkit.org
</td>
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<th>CC</th>
<td>bburg@apple.com, ggaren@apple.com, gskachkov@gmail.com, mattbaker@apple.com, sbarati@apple.com
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<th>Blocks</th>
<td>140855
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<pre>* SUMMARY
Unexpected exception assigning to this._property inside arrow function.
"TypeError: Attempted to assign to readonly property." is thrown when attempting to do something like "this._property = value" inside of an arrow function. I do not expect this to happen. "this" itself might be readonly, but "this._property" should writeable.
* TEST
<script>
"use strict";
class Logger {
constructor() {
this._id = undefined;
}
scheduleLog() {
if (this._id) return;
this._id = requestAnimationFrame(() => {
this._id = undefined;
console.log("Logged!");
});
}
}
var logger = new Logger;
logger.scheduleLog();
</script>
* STEPS TO REPRODUCE
1. Load the test case above
=> Unexpected exception</pre>
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