False positive and false negative in unnecessary_parentheses

[bwilkerson]

I created one issue instead of true because these might be related. It almost looks like a condition is reversed.

I believe the lint should produce a diagnostic for the following code, but does not.

class C {
  void m() {
    (1 + 2);
  }
}

removing the parentheses does not change the semantics of the code.

On the other hand, the lint should not produce a diagnostic for the following code, but does.

class C {
  void m() {
    ({1, 2, 3});
  }
}

removing the parentheses here causes the set literal to be interpreted as a block.