public function testFnCallChain()
{
$fn = function ($v) {
return $v + 1;
};
$fnChain = FnGen::fnCallChain($fn, $fn, $fn, $fn);
$this->assertTrue($fnChain(5) == 9);
// More useful example:
$values = array(array('name' => 'Terry', 'age' => 22), array('name' => 'Bob', 'age' => 30), array('name' => 'Sam', 'age' => 19), array('name' => 'Robert', 'age' => 55), array('group' => 'student'));
$fnLen = function ($v) {
return strlen($v);
};
// Extract only the elements with with name length of 3
$results = Sequence::make($values)->filter(FnGen::fnCallChain(FnGen::fnPluck('name'), $fnLen, FnGen::fnIsEqual(3)))->to_a();
$this->assertTrue(count($results) == 2);
// Same thing, but without the chain.
$resultsNonChain = Sequence::make($values)->filter(function ($v) {
if (isset($v['name'])) {
$x = $v['name'];
} else {
$x = '';
}
$len = strlen($x);
return $len == 3;
})->to_a();
$this->assertTrue($results == $resultsNonChain);
// The first function in the chain is allowed multiple params
$results = Sequence::make($values)->filterKeys(FnGen::fnCallChain(function ($k, $v) {
return $v;
}, FnGen::fnPluck('name'), $fnLen, FnGen::fnIsEqual(3)))->to_a();
$this->assertTrue(count($results) == 2);
}
public function testGroupBy()
{
$fruitOrders = TestData::$fruit;
$fnExtractFruitCountsForName = function ($fruit, $name) {
return Sequence::make($fruit)->filter(FnGen::fnCallChain(FnGen::fnPluck('name'), FnGen::fnIsEqual($name)))->values()->to_a();
};
$fruitByName = Sequence::make($fruitOrders)->groupBy(FnGen::fnPluck('name'))->to_a();
foreach ($fruitByName as $name => $orders) {
$filteredOrders = $fnExtractFruitCountsForName($fruitOrders, $name);
$this->assertEquals($filteredOrders, $orders);
}
$peopleByAge = Sequence::make(TestData::$people)->groupBy(fn\fnPluck('age'), array_fill(0, 100, array()))->toArray();
$this->assertEquals(array(), $peopleByAge[0]);
$peopleAge55 = Sequence::make(TestData::$people)->filter(fn\fnCallChain(fn\fnPluck('age'), fn\fnIsEqual(55)))->toValues();
$this->assertEquals($peopleAge55, $peopleByAge[55]);
// Test late binding of $init
$peopleByAgeFnInit = Sequence::make(TestData::$people)->groupBy(fn\fnPluck('age'), function () {
return array_fill(0, 100, array());
})->toArray();
$this->assertEquals($peopleByAge, $peopleByAgeFnInit);
}
