Assertion Error Messages

This lesson is a "quick tip" to emphasize that you need to pick the proper assertion to get the correct assertion error.

For example, we have a simple Service for converting currencies.

app/Services/CurrencyService.php:

class CurrencyService
{
    const RATES = [
        'usd' => [
            'eur' => 0.98
        ],
    ];
 
    public function convert(float $amount, string $currencyFrom, string $currencyTo): float
    {
        $rate = self::RATES[$currencyFrom][$currencyTo] ?? 0;
 
        return round($amount * $rate, 2);
    }
}

Then, in the unit test, we expect the...