# encoding: utf-8

require 'test_helper'

class Filters
  include Liquid::StandardFilters
end

class TestThing
  attr_reader :foo

  def initialize
    @foo = 0
  end

  def to_s
    "woot: #{@foo}"
  end

  def [](whatever)
    to_s
  end

  def to_liquid
    @foo += 1
    self
  end
end

class TestDrop < Liquid::Drop
  def test
    "testfoo"
  end
end

class TestEnumerable < Liquid::Drop
  include Enumerable

  def each(&block)
    [ { "foo" => 1, "bar" => 2 }, { "foo" => 2, "bar" => 1 }, { "foo" => 3, "bar" => 3 } ].each(&block)
  end
end

class NumberLikeThing < Liquid::Drop
  def initialize(amount)
    @amount = amount
  end

  def to_number
    @amount
  end
end

class StandardFiltersTest < Minitest::Test
  include Liquid

  def setup
    @filters = Filters.new
  end

  def test_size
    assert_equal 3, @filters.size([1, 2, 3])
    assert_equal 0, @filters.size([])
    assert_equal 0, @filters.size(nil)
  end

  def test_downcase
    assert_equal 'testing', @filters.downcase("Testing")
    assert_equal '', @filters.downcase(nil)
  end

  def test_upcase
    assert_equal 'TESTING', @filters.upcase("Testing")
    assert_equal '', @filters.upcase(nil)
  end

  def test_slice
    assert_equal 'oob', @filters.slice('foobar', 1, 3)
    assert_equal 'oobar', @filters.slice('foobar', 1, 1000)
    assert_equal '', @filters.slice('foobar', 1, 0)
    assert_equal 'o', @filters.slice('foobar', 1, 1)
    assert_equal 'bar', @filters.slice('foobar', 3, 3)
    assert_equal 'ar', @filters.slice('foobar', -2, 2)
    assert_equal 'ar', @filters.slice('foobar', -2, 1000)
    assert_equal 'r', @filters.slice('foobar', -1)
    assert_equal '', @filters.slice(nil, 0)
    assert_equal '', @filters.slice('foobar', 100, 10)
    assert_equal '', @filters.slice('foobar', -100, 10)
    assert_equal 'oob', @filters.slice('foobar', '1', '3')
    assert_raises(Liquid::ArgumentError) do
      @filters.slice('foobar', nil)
    end
    assert_raises(Liquid::ArgumentError) do
      @filters.slice('foobar', 0, "")
    end
  end

  def test_slice_on_arrays
    input = 'foobar'.split(//)
    assert_equal %w(o o b), @filters.slice(input, 1, 3)
    assert_equal %w(o o b a r), @filters.slice(input, 1, 1000)
    assert_equal %w(), @filters.slice(input, 1, 0)
    assert_equal %w(o), @filters.slice(input, 1, 1)
    assert_equal %w(b a r), @filters.slice(input, 3, 3)
    assert_equal %w(a r), @filters.slice(input, -2, 2)
    assert_equal %w(a r), @filters.slice(input, -2, 1000)
    assert_equal %w(r), @filters.slice(input, -1)
    assert_equal %w(), @filters.slice(input, 100, 10)
    assert_equal %w(), @filters.slice(input, -100, 10)
  end

  def test_truncate
    assert_equal '1234...', @filters.truncate('1234567890', 7)
    assert_equal '1234567890', @filters.truncate('1234567890', 20)
    assert_equal '...', @filters.truncate('1234567890', 0)
    assert_equal '1234567890', @filters.truncate('1234567890')
    assert_equal "测试...", @filters.truncate("测试测试测试测试", 5)
    assert_equal '12341', @filters.truncate("1234567890", 5, 1)
  end

  def test_split
    assert_equal ['12', '34'], @filters.split('12~34', '~')
    assert_equal ['A? ', ' ,Z'], @filters.split('A? ~ ~ ~ ,Z', '~ ~ ~')
    assert_equal ['A?Z'], @filters.split('A?Z', '~')
    assert_equal [], @filters.split(nil, ' ')
    assert_equal ['A', 'Z'], @filters.split('A1Z', 1)
  end

  def test_escape
    assert_equal '&lt;strong&gt;', @filters.escape('<strong>')
    assert_equal '1', @filters.escape(1)
    assert_equal '2001-02-03', @filters.escape(Date.new(2001, 2, 3))
    assert_nil @filters.escape(nil)
  end

  def test_h
    assert_equal '&lt;strong&gt;', @filters.h('<strong>')
    assert_equal '1', @filters.h(1)
    assert_equal '2001-02-03', @filters.h(Date.new(2001, 2, 3))
    assert_nil @filters.h(nil)
  end

  def test_escape_once
    assert_equal '&lt;strong&gt;Hulk&lt;/strong&gt;', @filters.escape_once('&lt;strong&gt;Hulk</strong>')
  end

  def test_url_encode
    assert_equal 'foo%2B1%40example.com', @filters.url_encode('foo+1@example.com')
    assert_equal '1', @filters.url_encode(1)
    assert_equal '2001-02-03', @filters.url_encode(Date.new(2001, 2, 3))
    assert_nil @filters.url_encode(nil)
  end

  def test_url_decode
    assert_equal 'foo bar', @filters.url_decode('foo+bar')
    assert_equal 'foo bar', @filters.url_decode('foo%20bar')
    assert_equal 'foo+1@example.com', @filters.url_decode('foo%2B1%40example.com')
    assert_equal '1', @filters.url_decode(1)
    assert_equal '2001-02-03', @filters.url_decode(Date.new(2001, 2, 3))
    assert_nil @filters.url_decode(nil)
  end

  def test_truncatewords
    assert_equal 'one two three', @filters.truncatewords('one two three', 4)
    assert_equal 'one two...', @filters.truncatewords('one two three', 2)
    assert_equal 'one two three', @filters.truncatewords('one two three')
    assert_equal 'Two small (13&#8221; x 5.5&#8221; x 10&#8221; high) baskets fit inside one large basket (13&#8221;...', @filters.truncatewords('Two small (13&#8221; x 5.5&#8221; x 10&#8221; high) baskets fit inside one large basket (13&#8221; x 16&#8221; x 10.5&#8221; high) with cover.', 15)
    assert_equal "测试测试测试测试", @filters.truncatewords('测试测试测试测试', 5)
    assert_equal 'one two1', @filters.truncatewords("one two three", 2, 1)
  end

  def test_strip_html
    assert_equal 'test', @filters.strip_html("<div>test</div>")
    assert_equal 'test', @filters.strip_html("<div id='test'>test</div>")
    assert_equal '', @filters.strip_html("<script type='text/javascript'>document.write('some stuff');</script>")
    assert_equal '', @filters.strip_html("<style type='text/css'>foo bar</style>")
    assert_equal 'test', @filters.strip_html("<div\nclass='multiline'>test</div>")
    assert_equal 'test', @filters.strip_html("<!-- foo bar \n test -->test")
    assert_equal '', @filters.strip_html(nil)
  end

  def test_join
    assert_equal '1 2 3 4', @filters.join([1, 2, 3, 4])
    assert_equal '1 - 2 - 3 - 4', @filters.join([1, 2, 3, 4], ' - ')
    assert_equal '1121314', @filters.join([1, 2, 3, 4], 1)
  end

  def test_sort
    assert_equal [1, 2, 3, 4], @filters.sort([4, 3, 2, 1])
    assert_equal [{ "a" => 1 }, { "a" => 2 }, { "a" => 3 }, { "a" => 4 }], @filters.sort([{ "a" => 4 }, { "a" => 3 }, { "a" => 1 }, { "a" => 2 }], "a")
  end

  def test_sort_with_nils
    assert_equal [1, 2, 3, 4, nil], @filters.sort([nil, 4, 3, 2, 1])
    assert_equal [{ "a" => 1 }, { "a" => 2 }, { "a" => 3 }, { "a" => 4 }, {}], @filters.sort([{ "a" => 4 }, { "a" => 3 }, {}, { "a" => 1 }, { "a" => 2 }], "a")
  end

  def test_sort_when_property_is_sometimes_missing_puts_nils_last
    input = [
      { "price" => 4, "handle" => "alpha" },
      { "handle" => "beta" },
      { "price" => 1, "handle" => "gamma" },
      { "handle" => "delta" },
      { "price" => 2, "handle" => "epsilon" }
    ]
    expectation = [
      { "price" => 1, "handle" => "gamma" },
      { "price" => 2, "handle" => "epsilon" },
      { "price" => 4, "handle" => "alpha" },
      { "handle" => "delta" },
      { "handle" => "beta" }
    ]
    assert_equal expectation, @filters.sort(input, "price")
  end

  def test_sort_natural
    assert_equal ["a", "B", "c", "D"], @filters.sort_natural(["c", "D", "a", "B"])
    assert_equal [{ "a" => "a" }, { "a" => "B" }, { "a" => "c" }, { "a" => "D" }], @filters.sort_natural([{ "a" => "D" }, { "a" => "c" }, { "a" => "a" }, { "a" => "B" }], "a")
  end

  def test_sort_natural_with_nils
    assert_equal ["a", "B", "c", "D", nil], @filters.sort_natural([nil, "c", "D", "a", "B"])
    assert_equal [{ "a" => "a" }, { "a" => "B" }, { "a" => "c" }, { "a" => "D" }, {}], @filters.sort_natural([{ "a" => "D" }, { "a" => "c" }, {}, { "a" => "a" }, { "a" => "B" }], "a")
  end

  def test_sort_natural_when_property_is_sometimes_missing_puts_nils_last
    input = [
      { "price" => "4", "handle" => "alpha" },
      { "handle" => "beta" },
      { "price" => "1", "handle" => "gamma" },
      { "handle" => "delta" },
      { "price" => 2, "handle" => "epsilon" }
    ]
    expectation = [
      { "price" => "1", "handle" => "gamma" },
      { "price" => 2, "handle" => "epsilon" },
      { "price" => "4", "handle" => "alpha" },
      { "handle" => "delta" },
      { "handle" => "beta" }
    ]
    assert_equal expectation, @filters.sort_natural(input, "price")
  end

  def test_sort_natural_case_check
    input = [
      { "key" => "X" },
      { "key" => "Y" },
      { "key" => "Z" },
      { "fake" => "t" },
      { "key" => "a" },
      { "key" => "b" },
      { "key" => "c" }
    ]
    expectation = [
      { "key" => "a" },
      { "key" => "b" },
      { "key" => "c" },
      { "key" => "X" },
      { "key" => "Y" },
      { "key" => "Z" },
      { "fake" => "t" }
    ]
    assert_equal expectation, @filters.sort_natural(input, "key")
    assert_equal ["a", "b", "c", "X", "Y", "Z"], @filters.sort_natural(["X", "Y", "Z", "a", "b", "c"])
  end

  def test_sort_empty_array
    assert_equal [], @filters.sort([], "a")
  end

  def test_sort_natural_empty_array
    assert_equal [], @filters.sort_natural([], "a")
  end

  def test_legacy_sort_hash
    assert_equal [{ a: 1, b: 2 }], @filters.sort({ a: 1, b: 2 })
  end

  def test_numerical_vs_lexicographical_sort
    assert_equal [2, 10], @filters.sort([10, 2])
    assert_equal [{ "a" => 2 }, { "a" => 10 }], @filters.sort([{ "a" => 10 }, { "a" => 2 }], "a")
    assert_equal ["10", "2"], @filters.sort(["10", "2"])
    assert_equal [{ "a" => "10" }, { "a" => "2" }], @filters.sort([{ "a" => "10" }, { "a" => "2" }], "a")
  end

  def test_uniq
    assert_equal ["foo"], @filters.uniq("foo")
    assert_equal [1, 3, 2, 4], @filters.uniq([1, 1, 3, 2, 3, 1, 4, 3, 2, 1])
    assert_equal [{ "a" => 1 }, { "a" => 3 }, { "a" => 2 }], @filters.uniq([{ "a" => 1 }, { "a" => 3 }, { "a" => 1 }, { "a" => 2 }], "a")
    testdrop = TestDrop.new
    assert_equal [testdrop], @filters.uniq([testdrop, TestDrop.new], 'test')
  end

  def test_uniq_empty_array
    assert_equal [], @filters.uniq([], "a")
  end

  def test_compact_empty_array
    assert_equal [], @filters.compact([], "a")
  end

  def test_reverse
    assert_equal [4, 3, 2, 1], @filters.reverse([1, 2, 3, 4])
  end

  def test_legacy_reverse_hash
    assert_equal [{ a: 1, b: 2 }], @filters.reverse(a: 1, b: 2)
  end

  def test_map
    assert_equal [1, 2, 3, 4], @filters.map([{ "a" => 1 }, { "a" => 2 }, { "a" => 3 }, { "a" => 4 }], 'a')
    assert_template_result 'abc', "{{ ary | map:'foo' | map:'bar' }}",
      'ary' => [{ 'foo' => { 'bar' => 'a' } }, { 'foo' => { 'bar' => 'b' } }, { 'foo' => { 'bar' => 'c' } }]
  end

  def test_map_doesnt_call_arbitrary_stuff
    assert_template_result "", '{{ "foo" | map: "__id__" }}'
    assert_template_result "", '{{ "foo" | map: "inspect" }}'
  end

  def test_map_calls_to_liquid
    t = TestThing.new
    assert_template_result "woot: 1", '{{ foo | map: "whatever" }}', "foo" => [t]
  end

  def test_map_on_hashes
    assert_template_result "4217", '{{ thing | map: "foo" | map: "bar" }}',
      "thing" => { "foo" => [ { "bar" => 42 }, { "bar" => 17 } ] }
  end

  def test_legacy_map_on_hashes_with_dynamic_key
    template = "{% assign key = 'foo' %}{{ thing | map: key | map: 'bar' }}"
    hash = { "foo" => { "bar" => 42 } }
    assert_template_result "42", template, "thing" => hash
  end

  def test_sort_calls_to_liquid
    t = TestThing.new
    Liquid::Template.parse('{{ foo | sort: "whatever" }}').render("foo" => [t])
    assert t.foo > 0
  end

  def test_map_over_proc
    drop = TestDrop.new
    p = proc{ drop }
    templ = '{{ procs | map: "test" }}'
    assert_template_result "testfoo", templ, "procs" => [p]
  end

  def test_map_over_drops_returning_procs
    drops = [
      {
        "proc" => ->{ "foo" },
      },
      {
        "proc" => ->{ "bar" },
      },
    ]
    templ = '{{ drops | map: "proc" }}'
    assert_template_result "foobar", templ, "drops" => drops
  end

  def test_map_works_on_enumerables
    assert_template_result "123", '{{ foo | map: "foo" }}', "foo" => TestEnumerable.new
  end

  def test_sort_works_on_enumerables
    assert_template_result "213", '{{ foo | sort: "bar" | map: "foo" }}', "foo" => TestEnumerable.new
  end

  def test_first_and_last_call_to_liquid
    assert_template_result 'foobar', '{{ foo | first }}', 'foo' => [ThingWithToLiquid.new]
    assert_template_result 'foobar', '{{ foo | last }}', 'foo' => [ThingWithToLiquid.new]
  end

  def test_truncate_calls_to_liquid
    assert_template_result "wo...", '{{ foo | truncate: 5 }}', "foo" => TestThing.new
  end

  def test_date
    assert_equal 'May', @filters.date(Time.parse("2006-05-05 10:00:00"), "%B")
    assert_equal 'June', @filters.date(Time.parse("2006-06-05 10:00:00"), "%B")
    assert_equal 'July', @filters.date(Time.parse("2006-07-05 10:00:00"), "%B")

    assert_equal 'May', @filters.date("2006-05-05 10:00:00", "%B")
    assert_equal 'June', @filters.date("2006-06-05 10:00:00", "%B")
    assert_equal 'July', @filters.date("2006-07-05 10:00:00", "%B")

    assert_equal '2006-07-05 10:00:00', @filters.date("2006-07-05 10:00:00", "")
    assert_equal '2006-07-05 10:00:00', @filters.date("2006-07-05 10:00:00", "")
    assert_equal '2006-07-05 10:00:00', @filters.date("2006-07-05 10:00:00", "")
    assert_equal '2006-07-05 10:00:00', @filters.date("2006-07-05 10:00:00", nil)

    assert_equal '07/05/2006', @filters.date("2006-07-05 10:00:00", "%m/%d/%Y")

    assert_equal "07/16/2004", @filters.date("Fri Jul 16 01:00:00 2004", "%m/%d/%Y")
    assert_equal "#{Date.today.year}", @filters.date('now', '%Y')
    assert_equal "#{Date.today.year}", @filters.date('today', '%Y')
    assert_equal "#{Date.today.year}", @filters.date('Today', '%Y')

    assert_nil @filters.date(nil, "%B")

    assert_equal '', @filters.date('', "%B")

    with_timezone("UTC") do
      assert_equal "07/05/2006", @filters.date(1152098955, "%m/%d/%Y")
      assert_equal "07/05/2006", @filters.date("1152098955", "%m/%d/%Y")
    end
  end

  def test_first_last
    assert_equal 1, @filters.first([1, 2, 3])
    assert_equal 3, @filters.last([1, 2, 3])
    assert_nil @filters.first([])
    assert_nil @filters.last([])
  end

  def test_replace
    assert_equal '2 2 2 2', @filters.replace('1 1 1 1', '1', 2)
    assert_equal '2 2 2 2', @filters.replace('1 1 1 1', 1, 2)
    assert_equal '2 1 1 1', @filters.replace_first('1 1 1 1', '1', 2)
    assert_equal '2 1 1 1', @filters.replace_first('1 1 1 1', 1, 2)
    assert_template_result '2 1 1 1', "{{ '1 1 1 1' | replace_first: '1', 2 }}"
  end

  def test_remove
    assert_equal '   ', @filters.remove("a a a a", 'a')
    assert_equal '   ', @filters.remove("1 1 1 1", 1)
    assert_equal 'a a a', @filters.remove_first("a a a a", 'a ')
    assert_equal ' 1 1 1', @filters.remove_first("1 1 1 1", 1)
    assert_template_result 'a a a', "{{ 'a a a a' | remove_first: 'a ' }}"
  end

  def test_pipes_in_string_arguments
    assert_template_result 'foobar', "{{ 'foo|bar' | remove: '|' }}"
  end

  def test_strip
    assert_template_result 'ab c', "{{ source | strip }}", 'source' => " ab c  "
    assert_template_result 'ab c', "{{ source | strip }}", 'source' => " \tab c  \n \t"
  end

  def test_lstrip
    assert_template_result 'ab c  ', "{{ source | lstrip }}", 'source' => " ab c  "
    assert_template_result "ab c  \n \t", "{{ source | lstrip }}", 'source' => " \tab c  \n \t"
  end

  def test_rstrip
    assert_template_result " ab c", "{{ source | rstrip }}", 'source' => " ab c  "
    assert_template_result " \tab c", "{{ source | rstrip }}", 'source' => " \tab c  \n \t"
  end

  def test_strip_newlines
    assert_template_result 'abc', "{{ source | strip_newlines }}", 'source' => "a\nb\nc"
    assert_template_result 'abc', "{{ source | strip_newlines }}", 'source' => "a\r\nb\nc"
  end

  def test_newlines_to_br
    assert_template_result "a<br />\nb<br />\nc", "{{ source | newline_to_br }}", 'source' => "a\nb\nc"
  end

  def test_plus
    assert_template_result "2", "{{ 1 | plus:1 }}"
    assert_template_result "2.0", "{{ '1' | plus:'1.0' }}"

    assert_template_result "5", "{{ price | plus:'2' }}", 'price' => NumberLikeThing.new(3)
  end

  def test_minus
    assert_template_result "4", "{{ input | minus:operand }}", 'input' => 5, 'operand' => 1
    assert_template_result "2.3", "{{ '4.3' | minus:'2' }}"

    assert_template_result "5", "{{ price | minus:'2' }}", 'price' => NumberLikeThing.new(7)
  end

  def test_abs
    assert_template_result "17", "{{ 17 | abs }}"
    assert_template_result "17", "{{ -17 | abs }}"
    assert_template_result "17", "{{ '17' | abs }}"
    assert_template_result "17", "{{ '-17' | abs }}"
    assert_template_result "0", "{{ 0 | abs }}"
    assert_template_result "0", "{{ '0' | abs }}"
    assert_template_result "17.42", "{{ 17.42 | abs }}"
    assert_template_result "17.42", "{{ -17.42 | abs }}"
    assert_template_result "17.42", "{{ '17.42' | abs }}"
    assert_template_result "17.42", "{{ '-17.42' | abs }}"
  end

  def test_times
    assert_template_result "12", "{{ 3 | times:4 }}"
    assert_template_result "0", "{{ 'foo' | times:4 }}"
    assert_template_result "6", "{{ '2.1' | times:3 | replace: '.','-' | plus:0}}"
    assert_template_result "7.25", "{{ 0.0725 | times:100 }}"
    assert_template_result "-7.25", '{{ "-0.0725" | times:100 }}'
    assert_template_result "7.25", '{{ "-0.0725" | times: -100 }}'
    assert_template_result "4", "{{ price | times:2 }}", 'price' => NumberLikeThing.new(2)
  end

  def test_divided_by
    assert_template_result "4", "{{ 12 | divided_by:3 }}"
    assert_template_result "4", "{{ 14 | divided_by:3 }}"

    assert_template_result "5", "{{ 15 | divided_by:3 }}"
    assert_equal "Liquid error: divided by 0", Template.parse("{{ 5 | divided_by:0 }}").render

    assert_template_result "0.5", "{{ 2.0 | divided_by:4 }}"
    assert_raises(Liquid::ZeroDivisionError) do
      assert_template_result "4", "{{ 1 | modulo: 0 }}"
    end

    assert_template_result "5", "{{ price | divided_by:2 }}", 'price' => NumberLikeThing.new(10)
  end

  def test_modulo
    assert_template_result "1", "{{ 3 | modulo:2 }}"
    assert_raises(Liquid::ZeroDivisionError) do
      assert_template_result "4", "{{ 1 | modulo: 0 }}"
    end

    assert_template_result "1", "{{ price | modulo:2 }}", 'price' => NumberLikeThing.new(3)
  end

  def test_round
    assert_template_result "5", "{{ input | round }}", 'input' => 4.6
    assert_template_result "4", "{{ '4.3' | round }}"
    assert_template_result "4.56", "{{ input | round: 2 }}", 'input' => 4.5612
    assert_raises(Liquid::FloatDomainError) do
      assert_template_result "4", "{{ 1.0 | divided_by: 0.0 | round }}"
    end

    assert_template_result "5", "{{ price | round }}", 'price' => NumberLikeThing.new(4.6)
    assert_template_result "4", "{{ price | round }}", 'price' => NumberLikeThing.new(4.3)
  end

  def test_ceil
    assert_template_result "5", "{{ input | ceil }}", 'input' => 4.6
    assert_template_result "5", "{{ '4.3' | ceil }}"
    assert_raises(Liquid::FloatDomainError) do
      assert_template_result "4", "{{ 1.0 | divided_by: 0.0 | ceil }}"
    end

    assert_template_result "5", "{{ price | ceil }}", 'price' => NumberLikeThing.new(4.6)
  end

  def test_floor
    assert_template_result "4", "{{ input | floor }}", 'input' => 4.6
    assert_template_result "4", "{{ '4.3' | floor }}"
    assert_raises(Liquid::FloatDomainError) do
      assert_template_result "4", "{{ 1.0 | divided_by: 0.0 | floor }}"
    end

    assert_template_result "5", "{{ price | floor }}", 'price' => NumberLikeThing.new(5.4)
  end

  def test_at_most
    assert_template_result "4", "{{ 5 | at_most:4 }}"
    assert_template_result "5", "{{ 5 | at_most:5 }}"
    assert_template_result "5", "{{ 5 | at_most:6 }}"

    assert_template_result "4.5", "{{ 4.5 | at_most:5 }}"
    assert_template_result "5", "{{ width | at_most:5 }}", 'width' => NumberLikeThing.new(6)
    assert_template_result "4", "{{ width | at_most:5 }}", 'width' => NumberLikeThing.new(4)
    assert_template_result "4", "{{ 5 | at_most: width }}", 'width' => NumberLikeThing.new(4)
  end

  def test_at_least
    assert_template_result "5", "{{ 5 | at_least:4 }}"
    assert_template_result "5", "{{ 5 | at_least:5 }}"
    assert_template_result "6", "{{ 5 | at_least:6 }}"

    assert_template_result "5", "{{ 4.5 | at_least:5 }}"
    assert_template_result "6", "{{ width | at_least:5 }}", 'width' => NumberLikeThing.new(6)
    assert_template_result "5", "{{ width | at_least:5 }}", 'width' => NumberLikeThing.new(4)
    assert_template_result "6", "{{ 5 | at_least: width }}", 'width' => NumberLikeThing.new(6)
  end

  def test_append
    assigns = { 'a' => 'bc', 'b' => 'd' }
    assert_template_result('bcd', "{{ a | append: 'd'}}", assigns)
    assert_template_result('bcd', "{{ a | append: b}}", assigns)
  end

  def test_concat
    assert_equal [1, 2, 3, 4], @filters.concat([1, 2], [3, 4])
    assert_equal [1, 2, 'a'],  @filters.concat([1, 2], ['a'])
    assert_equal [1, 2, 10],   @filters.concat([1, 2], [10])

    assert_raises(Liquid::ArgumentError, "concat filter requires an array argument") do
      @filters.concat([1, 2], 10)
    end
  end

  def test_prepend
    assigns = { 'a' => 'bc', 'b' => 'a' }
    assert_template_result('abc', "{{ a | prepend: 'a'}}", assigns)
    assert_template_result('abc', "{{ a | prepend: b}}", assigns)
  end

  def test_default
    assert_equal "foo", @filters.default("foo", "bar")
    assert_equal "bar", @filters.default(nil, "bar")
    assert_equal "bar", @filters.default("", "bar")
    assert_equal "bar", @filters.default(false, "bar")
    assert_equal "bar", @filters.default([], "bar")
    assert_equal "bar", @filters.default({}, "bar")
  end

  def test_cannot_access_private_methods
    assert_template_result('a', "{{ 'a' | to_number }}")
  end

  def test_date_raises_nothing
    assert_template_result('', "{{ '' | date: '%D' }}")
    assert_template_result('abc', "{{ 'abc' | date: '%D' }}")
  end

  private

  def with_timezone(tz)
    old_tz = ENV['TZ']
    ENV['TZ'] = tz
    yield
  ensure
    ENV['TZ'] = old_tz
  end
end # StandardFiltersTest
