impactjs test for Entity.touches off-by-one issue

Entity.touches.test.js

// try with and without this next block
if (0) {
  ig.Entity.prototype.touches = function( other ) {		
	return !(
		this.pos.x >= other.pos.x + other.size.x ||
		this.pos.x + this.size.x <= other.pos.x ||
		this.pos.y >= other.pos.y + other.size.y ||
		this.pos.y + this.size.y <= other.pos.y
	);
  };
}

var e1 = new ig.Entity();
e1.pos.x = 0;
e1.pos.y = 0;
e1.size.x = 1;
e1.size.y = 1;

var e2 = new ig.Entity();
e2.pos.x = 0;
e2.pos.y = 0;
e2.size.x = 1;
e2.size.y = 1;

console.log("testing x");
for (var x=-5; x<5; x++) {
	e2.pos.x = x;
	console.log(x, e1.touches(e2));
}

console.log("testing y");
e2.pos.x = 0;
for (var y=-5; y<5; y++) {
	e2.pos.y = y;
	console.log(y, e1.touches(e2));
}