test.flatten_array.js

'use strict';

// MODULES //

var tape = require( 'tape' );
var flattenArray = require( './../lib/flatten_array.js' );


// TESTS //

tape( 'main export is a function', function test( t ) {
	t.ok( true, __filename );
	t.equal( typeof flattenArray, 'function', 'main export is a function' );
	t.end();
});

tape( 'the function throws an error if not provided an array', function test( t ) {
	var values;
	var i;

	values = [
		'5',
		5,
		NaN,
		null,
		undefined,
		true,
		{},
		function(){}
	];
	for ( i = 0; i < values.length; i++ ) {
		t.throws( badValue( values[i] ), TypeError, 'throws a type error when provided '+values[i] );
	}
	t.end();

	function badValue( value ) {
		return function badValue() {
			flattenArray( value );
		};
	}
});

tape( 'the function throws an error if not provided an array (options)', function test( t ) {
	var values;
	var i;

	values = [
		'5',
		5,
		NaN,
		null,
		undefined,
		true,
		{},
		function(){}
	];
	for ( i = 0; i < values.length; i++ ) {
		t.throws( badValue( values[i] ), TypeError, 'throws a type error when provided '+values[i] );
	}
	t.end();

	function badValue( value ) {
		return function badValue() {
			flattenArray( value, {} );
		};
	}
});

tape( 'the function throws an error if provided an options argument which is not an object', function test( t ) {
	var values;
	var i;

	values = [
		'5',
		5,
		NaN,
		null,
		undefined,
		true,
		[],
		function(){}
	];
	for ( i = 0; i < values.length; i++ ) {
		t.throws( badValue( values[i] ), TypeError, 'throws a type error when provided '+values[i] );
	}
	t.end();

	function badValue( value ) {
		return function badValue() {
			flattenArray( [], value );
		};
	}
});

tape( 'the function throws an error if provided an invalid option', function test( t ) {
	var values;
	var i;

	values = [
		'5',
		5,
		NaN,
		null,
		undefined,
		[],
		{},
		function(){}
	];
	for ( i = 0; i < values.length; i++ ) {
		t.throws( badValue( values[i] ), TypeError, 'throws a type error when provided '+values[i] );
	}
	t.end();

	function badValue( value ) {
		return function badValue() {
			flattenArray( [], {
				'copy': value
			});
		};
	}
});

tape( 'if the `depth` option is `0`, the function returns the input array', function test( t ) {
	var expected;
	var actual;
	var arr;

	expected = [ 1, [2, [3], 4], 5 ];
	arr = [ 1, [2, [3], 4], 5 ];
	actual = flattenArray( arr, {
		'depth': 0
	});

	t.equal( arr, actual, 'same reference' );
	t.deepEqual( actual, expected, 'deep equal' );

	t.end();
});

tape( 'if the `depth` option is `0` and the `copy` option is `true`, the function returns a deep copy of the input array', function test( t ) {
	var expected;
	var actual;
	var arr;

	expected = [ 1, [2, [3], 4], 5 ];
	arr = [ 1, [2, [3], 4], 5 ];
	actual = flattenArray( arr, {
		'depth': 0,
		'copy': true
	});

	t.notEqual( arr, actual, 'different reference' );
	t.deepEqual( actual, expected, 'deep equal' );

	t.end();
});

tape( 'the function flattens an array', function test( t ) {
	var expected;
	var actual;
	var arr;

	arr = [ 1, [2, [3, [4, [ 5 ], 6], 7], 8], 9 ];

	actual = flattenArray( arr );
	expected = [ 1, 2, 3, 4, 5, 6, 7, 8, 9 ];

	t.deepEqual( actual, expected, 'deep equal' );
	t.end();
});

tape( 'the function flattens an array to a specified depth', function test( t ) {
	var expected;
	var actual;
	var arr;

	arr = [ 1, [2, [3, [4, [ 5 ], 6], 7], 8], 9 ];

	actual = flattenArray( arr, {
		'depth': 2
	});
	expected = [ 1, 2, 3, [4, [5], 6], 7, 8, 9 ];

	t.deepEqual( actual, expected, 'deep equal' );
	t.equal( arr[1][1][1], actual[3], 'same reference' );
	t.end();
});

tape( 'the function supports flattening an array to a specified depth with deep copying', function test( t ) {
	var expected;
	var actual;
	var arr;

	arr = [ 1, [2, [3, [4, [ 5 ], 6], 7], 8], 9 ];

	actual = flattenArray( arr, {
		'depth': 2,
		'copy': true
	});
	expected = [ 1, 2, 3, [4, [5], 6], 7, 8, 9 ];

	t.deepEqual( actual, expected, 'deep equal' );
	t.notEqual( arr[1][1][1], actual[3], 'different references' );
	t.end();
});

tape( 'the function supports an option indicating if all array elements have the same dimensions', function test( t ) {
	var expected;
	var actual;
	var arr;

	arr = [
		[ [ 1, 2, 3 ] ],
		[ [ 4, 5, 6 ] ],
		[ [ 7, 8, 9 ] ],
		[ [ 10, 11, 12 ] ]
	];

	actual = flattenArray( arr, {
		'equalDims': true
	});
	expected = [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 ];

	t.deepEqual( actual, expected, 'deep equal' );
	t.end();
});