no-compare-relation-boolean.md

Disallow comparing relational expressions to booleans in assertions (qunit/no-compare-relation-boolean)

💼 This rule is enabled in the ✅ recommended config.

🔧 This rule is automatically fixable by the --fix CLI option.

Sometimes, QUnit assertions contain relations (such as expected === actual). Many of these relations can be expressed better using different assertion methods (such as assert.strictEqual). However, even for those comparisons which cannot easily be expressed (such as actual > expected), comparing those results explicitly to true or false provides no added value, because the assertion will show that true equals or does not equal true.

In any comparison between a relational expression (actual > expected) and a boolean, it is at least possible to convert the assertion to use assert.ok or assert.notOk. In addition, custom assertions could be used or created to provide better output.

Rule Details

The following patterns are considered warnings:

assert.equal(a === b, true);
assert.equal(true, a === b);

assert.strictEqual(a > b, false);
assert.strictEqual(false, a > b);

assert.deepEqual(a === b, true);
assert.deepEqual(true, a === b);

assert.propEqual(a <= b, false);
assert.propEqual(false, a <= b);

assert.notEqual(a == b, true);
assert.notEqual(true, a == b);

// etc. for all negated equality assertions

The following patterns are not warnings:

assert.equal(a, b);

assert.ok(a === b);

assert.ok(a > b);

When Not To Use It

If you are not concerned with the formatting of assertions in any QUnit reporter, you can safely disable this rule.