False positive in SA1119, if (!(value is Type type)) erroneously reports inner parentheses unnecessary.

[Flynn1179]

This is a new one in C#7

The ability to also declare a variable using a type pattern causes the unnecessary parenthesis warning to appear.

This works, and correctly allows it with no warning:

if (!(value is Type)) { .. }

This doesn't:

if (!(value is Type type)) { /* do something with type */ }

The inner parenthesis are reported as unnecessary, but they're definitely not.

[sharwell]

Duplicate of #2372 😄

[Flynn1179]

Odd, I searched for SA1119, didn't find it. Sorry!

[sharwell]

@Flynn1179 No problem, we prefer a duplicate than no issue filed at all 😄

[Flynn1179]

Ah, identified my error: I left the default is:open clause in the search, and didn't consider the possibility it had already been fixed, having updated to the latest released version this morning. Lesson learned!