function FractionUnitTestCase::testFraction in Fraction 7

Test the Fraction class and it's methods.

File

./fraction.test, line 32

Fraction tests

Class

FractionUnitTestCase

Provides tests for the Fraction class.

Code

function testFraction() {

  // Test creation of a fraction.
  $fraction = fraction(1, 2);
  $numerator = $fraction
    ->getNumerator();
  $denominator = $fraction
    ->getDenominator();
  $message = 'A fraction of 1/2 should return a numerator of 1.';
  $this
    ->assertEqual($numerator, '1', $message);
  $message = 'A fraction of 1/2 should return a denominator of 2.';
  $this
    ->assertEqual($denominator, '2', $message);

  // Test creation of an empty fraction.
  $fraction = fraction();
  $numerator = $fraction
    ->getNumerator();
  $denominator = $fraction
    ->getDenominator();
  $message = 'An empty fraction should return a numerator of 0.';
  $this
    ->assertEqual($numerator, '0', $message);
  $message = 'An empty fraction should return a denominator of 1.';
  $this
    ->assertEqual($denominator, '1', $message);

  // Test returning a fraction as a string.
  $result = fraction(1, 2)
    ->toString();
  $message = 'A fraction with a numerator of 1 and a denominator of 2 should return a string of "1/2".';
  $this
    ->assertEqual($result, '1/2', $message);

  // Test returning a fraction as a string with a different separator.
  $result = fraction(1, 2)
    ->toString(':');
  $message = 'A fraction with a numerator of 1 and a denominator of 2 should return a string of "1:2" (when a colon separator is specified).';
  $this
    ->assertEqual($result, '1:2', $message);

  // Test division by zero.
  $result = fraction(1, 0)
    ->toString();
  $message = 'A fraction of 1/0 should return 0/1 (avoid division by zero).';
  $this
    ->assertEqual($result, '0/1', $message);

  // Test normalization of negative fractions.
  $result = fraction(-1, 2)
    ->toString();
  $message = 'A fraction of -1/2 should normalize to -1/2.';
  $this
    ->assertEqual($result, '-1/2', $message);
  $result = fraction(1, -2)
    ->toString();
  $message = 'A fraction of 1/-2 should normalize to -1/2.';
  $this
    ->assertEqual($result, '-1/2', $message);
  $result = fraction(-1, -2)
    ->toString();
  $message = 'A fraction of -1/-2 should normalize to 1/2.';
  $this
    ->assertEqual($result, '1/2', $message);

  // Test converting a fraction to a decimal.
  $result = fraction(1, 2)
    ->toDecimal(1);
  $message = 'A fraction of 1/2 should return a decimal of 0.5 (with precision 1)';
  $this
    ->assertEqual($result, '0.5', $message);

  // Test auto precision for non base 10 fractions.
  $result = fraction(1, 2)
    ->toDecimal(0, TRUE);
  $message = 'A fraction of 1/2 should return a decimal of 0.5 (with precision 0, auto_precision)';
  $this
    ->assertEqual($result, '0.5', $message);

  // Test decimal precision (rounding up).
  $result = fraction(1, 2)
    ->toDecimal(0);
  $message = 'A fraction of 1/2 with no precision should round to 1.';
  $this
    ->assertEqual($result, '1', $message);

  // Test decimal precision (rounding down).
  $result = fraction(2, 5)
    ->toDecimal(0);
  $message = 'A fraction of 2/5 with no precision should round to 0.';
  $this
    ->assertEqual($result, '0', $message);

  // Test decimal automatic precision.
  $result = fraction(1, 1000)
    ->toDecimal(2, TRUE);
  $message = 'A fraction of 1/1000 with precision 2 and auto-precision enabled should round to 0.001.';
  $this
    ->assertEqual($result, '0.001', $message);

  // Test creation of a fraction from a decimal.
  $result = fraction()
    ->fromDecimal(0.5)
    ->toString();
  $message = 'The fromDecimal() method should create a fraction of 5/10 from a decimal of 0.5.';
  $this
    ->assertEqual($result, '5/10', $message);

  // Test calculation of greatest common divisor.
  $result = fraction(5, 10)
    ->gcd();
  $message = 'The greatest common divisor of 1/2 is 5.';
  $this
    ->assertEqual($result, '5', $message);

  // Test reduction of a fraction to its simplest form.
  $result = fraction(5, 10)
    ->reduce()
    ->toString();
  $message = 'A fraction of 5/10 should be reducible to 1/2.';
  $this
    ->assertEqual($result, '1/2', $message);

  // Test fraction addition.
  $result = fraction(1, 2)
    ->add(fraction(1, 3))
    ->toString();
  $message = '1/2 + 1/3 = 5/6';
  $this
    ->assertEqual($result, '5/6', $message);

  // Test fraction subtraction.
  $result = fraction(2, 3)
    ->subtract(fraction(1, 7))
    ->toString();
  $message = '2/3 - 1/7 = 11/21';
  $this
    ->assertEqual($result, '11/21', $message);

  // Test fraction multiplication.
  $result = fraction(2, 5)
    ->multiply(fraction(1, 4))
    ->toString();
  $message = '2/5 * 1/4 = 2/20';
  $this
    ->assertEqual($result, '2/20', $message);

  // Test fraction division.
  $result = fraction(5, 7)
    ->divide(fraction(1, 5))
    ->toString();
  $message = '5/7 / 1/5 = 25/7';
  $this
    ->assertEqual($result, '25/7', $message);

  // Test fraction reciprocation.
  $result = fraction(1, 2)
    ->reciprocate()
    ->toString();
  $message = 'The reciprocal of 1/2 is 2/1.';
  $this
    ->assertEqual($result, '2/1', $message);

  // Test that reciprocation of a zero numerator does not result in division by zero.
  $result = fraction(0, 1)
    ->reciprocate()
    ->toString();
  $message = 'The reciprocal of 0/1 is 0/1 (avoid division by zero).';
  $this
    ->assertEqual($result, '0/1', $message);
}