exercism/elixir/strain/strain_test.exs

102 lines
2.2 KiB
Elixir

if !System.get_env("EXERCISM_TEST_EXAMPLES") do
Code.load_file("strain.exs", __DIR__)
end
ExUnit.start()
ExUnit.configure(trace: true, exclude: :pending)
defmodule StrainTest do
use ExUnit.Case
defp is_odd?(n), do: rem(n, 2) == 1
defp is_even?(n), do: rem(n, 2) == 0
defp noop(_), do: true
# @tag :pending
test "empty keep" do
assert Strain.keep([], &noop/1) == []
end
# @tag :pending
test "keep everything" do
assert Strain.keep([1, 2, 3], fn e -> e < 10 end) == [1, 2, 3]
end
# @tag :pending
test "keep first and last" do
assert Strain.keep([1, 2, 3], &is_odd?/1) == [1, 3]
end
# @tag :pending
test "keep neither first nor last" do
assert Strain.keep([1, 2, 3, 4, 5], &is_even?/1) == [2, 4]
end
# @tag :pending
test "keep strings" do
words = ~w(apple zebra banana zombies cherimoya zelot)
assert Strain.keep(words, &String.starts_with?(&1, "z")) == ~w(zebra zombies zelot)
end
# @tag :pending
test "keep arrays" do
rows = [
[1, 2, 3],
[5, 5, 5],
[5, 1, 2],
[2, 1, 2],
[1, 5, 2],
[2, 2, 1],
[1, 2, 5]
]
assert Strain.keep(rows, fn row -> 5 in row end) == [
[5, 5, 5],
[5, 1, 2],
[1, 5, 2],
[1, 2, 5]
]
end
# @tag :pending
test "empty discard" do
assert Strain.discard([], &noop/1) == []
end
# @tag :pending
test "discard nothing" do
assert Strain.discard([1, 2, 3], fn e -> e > 10 end) == [1, 2, 3]
end
# @tag :pending
test "discard first and last" do
assert Strain.discard([1, 2, 3], &is_odd?/1) == [2]
end
# @tag :pending
test "discard neither first nor last" do
assert Strain.discard([1, 2, 3, 4, 5], &is_even?/1) == [1, 3, 5]
end
# @tag :pending
test "discard strings" do
words = ~w(apple zebra banana zombies cherimoya zelot)
assert Strain.discard(words, &String.starts_with?(&1, "z")) == ~w(apple banana cherimoya)
end
# @tag :pending
test "discard arrays" do
rows = [
[1, 2, 3],
[5, 5, 5],
[5, 1, 2],
[2, 1, 2],
[1, 5, 2],
[2, 2, 1],
[1, 2, 5]
]
assert Strain.discard(rows, fn row -> 5 in row end) == [[1, 2, 3], [2, 1, 2], [2, 2, 1]]
end
end