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Complexity rule prefers and `&&` over or `||`

See original GitHub issue

ESLint Version: 3.19.0
Node Version: 7.7.3
npm Version: 4.5.0

What parser (default, Babel-ESLint, etc.) are you using? : babel-eslint

Please show your full configuration:

{
  "parser": "babel-eslint",
  "rules": {
    "complexity": [2, 1]
  }
}

What did you do? Please include the actual source code causing the issue.


let foo, bar, baz, bang;

function check(foo, bar, baz, bang) {
	if (!bar || !bang) {
		baz = foo;
	}
}
function check2(foo, bar, baz, bang) {
	if (!(bar && bang)) {
		baz = foo;
	}
}
function check3(foo, bar, baz, bang) {
	if (bar && bang) {
		baz = foo;
	}
}
function check4(foo, bar, baz, bang) {
	if (!bar && !bang) {
		baz = foo;
	}
}
function check5(foo, bar, baz, bang) {
	if (bar || bang) {
		baz = foo;
	}
}

check(foo, bar, baz, bang);
check2(foo, bar, baz, bang);
check3(foo, bar, baz, bang);
check4(foo, bar, baz, bang);
check5(foo, bar, baz, bang);

What did you expect to happen?

All functions check to check5 should have the same complexity

What actually happened? Please include the actual, raw output from ESLint.

   3:1  error  Function 'check' has a complexity of 3   complexity
   8:1  error  Function 'check2' has a complexity of 2  complexity
  13:1  error  Function 'check3' has a complexity of 2  complexity
  18:1  error  Function 'check4' has a complexity of 2  complexity
  23:1  error  Function 'check5' has a complexity of 3  complexity

It seems that || has more complexity than && in the current implementation, but I don’t think that is true. All the check have a complexity of 3. (That is what http://jsmeter.info/axtsgb/1#results reports)