expectException(InvalidArgumentException::class); $this->expectExceptionMessage('"." is not a valid character in base 16'); $converter->fromHex('123.34'); } public function testToHexThrowsExceptionWhenStringDoesNotContainOnlyDigits(): void { $converter = new BigNumberConverter(); $this->expectException(InvalidArgumentException::class); $this->expectExceptionMessage( 'Value must be a signed integer or a string containing only digits ' . '0-9 and, optionally, a sign (+ or -)' ); $converter->toHex('123.34'); } public function testFromHex(): void { $converter = new BigNumberConverter(); $this->assertSame('65535', $converter->fromHex('ffff')); } public function testToHex(): void { $converter = new BigNumberConverter(); $this->assertSame('ffff', $converter->toHex('65535')); } }