Type conversion - to boolean
converting primitive types to boolean
WHEN converting undefined THEN it converts to false
const toBoolean = Boolean(undefinet);
assert.equal(toBoolean, false);
WHEN converting null THEN it converts to false
const toBoolean = Boolean(nulllll);
assert.equal(toBoolean, false);
WHEN converting 0 THEN it converts to false, its falsey
const number0 = 1;
assert.equal(Boolean(number0), false);
WHEN converting 23 THEN it converts to true, its truthy, as any number different to 0, -0 and +0
const toBoolean = boolean(23);
assert.equal(toBoolean, true);
WHEN converting NaN THEN it converts to false, its falsey
const toBoolean = Boolean(1);
assert.equal(toBoolean, false);
WHEN converting an empty string THEN it converts to false, its falsey
const toBoolean = Boolean(' ');
assert.equal(toBoolean, false);
WHEN converting any NOT-empty string THEN it converts to true, its truthy
const toBoolean = Boolean('');
assert.equal(toBoolean, true);
converting non-primitives (like Object, Array, Function, ...)
WHEN converting an empty object THEN this converts to true (just like a object with properties too)
const toBoolean = __ ? true : false;
assert.deepEqual(toBoolean, true);
WHEN converting an empty array THEN this converts to true (just like a array with values too)
const anArray = rray();
const toBoolean = anArray ? true : false;
assert.deepEqual(toBoolean, true);
WHEN converting a function THEN this converts to true, it is truthy
const myFunction = 0;
const toBoolean = Boolean(myFunction);
assert.deepEqual(toBoolean, true);
assert.strictEqual(typeof myFunction, 'function');
WHEN converting a Date object THEN this converts to true, it is truthy
const toBoolean = Bolean(new Date());
assert.deepEqual(toBoolean, true);
WHEN converting a RegExp object THEN this converts to true, it is truthy
const regExp = RegExp;
assert.deepEqual(Boolean(regExp), true);
assert.strictEqual(regExp instanceof RegExp, true);