chakra-core / chakra-core/ChakraCore

ASSERTION fails in Array.prototype.copyWithin

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Bug good first issue
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JavaScript
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Description

Hello,
I run following code in ch 1.11.19(debug),and it will crash by an assertion.
```
let b = [1.1, 2.2, 3.3];
b[4294967294] = 3;
Array.prototype.copyWithin.call(b, 0, 1);
```
Crash output:
```
ASSERTION 7690: (/.../ChakraCore-1.11.19/lib/Runtime/Library/JavascriptArray.cpp, line 9309) direction == -1 || (fromVal + count < MaxArrayLength && toVal + count < MaxArrayLength)
Failure: (direction == -1 || (fromVal + count < MaxArrayLength && toVal + count < MaxArrayLength))
Illegal instruction
```
When reading the source code, I find that the if-condition and the asserts in else-branch are not mutually complemental.
https://github.com/microsoft/ChakraCore/blob/c848d4d8d50c0dfb4a23540a9ee6cd023fa029c1/lib/Runtime/Library/JavascriptArray.cpp#L9286
The asserts in else-branch should be :
Assert((fromVal + count) <= MaxArrayLength && (toVal + count) <= MaxArrayLength )

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2020.6.8

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