# SPDX-License-Identifier: Apache-2.0
# SPDX-FileCopyrightText: 2021 The Elixir Team
# SPDX-FileCopyrightText: 2012 Plataformatec

Code.require_file("test_helper.exs", __DIR__)

defmodule KernelTest do
  use ExUnit.Case, async: true

  # Skip these doctests are they emit warnings
  doctest Kernel,
    except:
      [===: 2, !==: 2, and: 2, or: 2] ++
        [is_exception: 1, is_exception: 2, is_nil: 1, is_struct: 1, is_non_struct_map: 1]

  def id(arg), do: arg
  def id(arg1, arg2), do: {arg1, arg2}
  def empty_map, do: %{}

  defp purge(module) do
    :code.purge(module)
    :code.delete(module)
  end

  defp assert_eval_raise(error, msg, string) do
    assert_raise error, msg, fn ->
      Code.eval_string(string)
    end
  end

  test "op ambiguity" do
    max = 1
    assert max == 1
    assert max(1, 2) == 2
  end

  describe "=/2" do
    test "can be reassigned" do
      var = 1
      id(var)
      var = 2
      assert var == 2
    end

    test "can be reassigned inside a list" do
      _ = [var = 1, 2, 3]
      id(var)
      _ = [var = 2, 3, 4]
      assert var == 2
    end

    test "can be reassigned inside a keyword list" do
      _ = [a: var = 1, b: 2]
      id(var)
      _ = [b: var = 2, c: 3]
      assert var == 2
    end

    test "can be reassigned inside a call" do
      id(var = 1)
      id(var)
      id(var = 2)
      assert var == 2
    end

    test "can be reassigned inside a multi-argument call" do
      id(:arg, var = 1)
      id(:arg, var)
      id(:arg, var = 2)
      assert var == 2

      id(:arg, a: 1, b: var = 2)
      id(:arg, var)
      id(:arg, b: 2, c: var = 3)
      assert var == 3
    end

    test "++/2 works in matches" do
      [1, 2] ++ var = [1, 2]
      assert var == []

      [1, 2] ++ var = [1, 2, 3]
      assert var == [3]

      ~c"ab" ++ var = ~c"abc"
      assert var == ~c"c"

      [:a, :b] ++ var = [:a, :b, :c]
      assert var == [:c]
    end
  end

  test "=~/2" do
    assert "abcd" =~ ~r/c(d)/ == true
    assert "abcd" =~ ~r/e/ == false

    string = "^ab+cd*$"
    assert string =~ "ab+" == true
    assert string =~ "bb" == false

    assert "abcd" =~ ~r// == true
    assert "abcd" =~ "" == true

    assert "" =~ ~r// == true
    assert "" =~ "" == true

    assert "" =~ "abcd" == false
    assert "" =~ ~r/abcd/ == false
  end

  test "^" do
    x = List.first([1])

    assert_raise MatchError, fn ->
      {x, ^x} = {2, 2}
      x
    end
  end

  # Note we use `==` in assertions so `assert` does not rewrite `match?/2`.
  test "match?/2" do
    a = List.first([0])
    assert match?(b when b > a, 1) == true
    assert binding() == [a: 0]

    assert match?(b when b > a, -1) == false
    assert binding() == [a: 0]

    # Does not warn on underscored variables
    assert match?(_unused, a) == true
  end

  def exported?, do: not_exported?()
  defp not_exported?, do: true

  test "function_exported?/3" do
    assert function_exported?(__MODULE__, :exported?, 0)
    refute function_exported?(__MODULE__, :not_exported?, 0)
  end

  test "macro_exported?/3" do
    assert macro_exported?(Kernel, :in, 2) == true
    assert macro_exported?(Kernel, :def, 1) == true
    assert macro_exported?(Kernel, :def, 2) == true
    assert macro_exported?(Kernel, :def, 3) == false
    assert macro_exported?(Kernel, :no_such_macro, 2) == false
    assert macro_exported?(:erlang, :abs, 1) == false
  end

  test "apply/3 and apply/2" do
    assert apply(Enum, :reverse, [[1 | [2, 3]]]) == [3, 2, 1]
    assert apply(fn x -> x * 2 end, [2]) == 4
  end

  test "binding/0 and binding/1" do
    x = 1
    assert binding() == [x: 1]

    x = 2
    assert binding() == [x: 2]

    y = 3
    assert binding() == [x: 2, y: 3]

    var!(x, :foo) = 4
    assert binding() == [x: 2, y: 3]
    assert binding(:foo) == [x: 4]

    # No warnings
    _x = 1
    assert binding() == [_x: 1, x: 2, y: 3]
  end

  defmodule User do
    assert is_map(defstruct name: "john")
    # Ensure we keep the line information around.
    # It is important for debugging tools, ExDoc, etc.
    {:v1, :def, anno, _clauses} = Module.get_definition(__MODULE__, {:__struct__, 1})
    anno[:line] == __ENV__.line - 4
  end

  test "struct/1 and struct/2" do
    assert struct(User) == %User{name: "john"}

    user = struct(User, name: "meg")
    assert user == %User{name: "meg"}
    assert struct(user, %{name: "meg"}) == user

    assert struct(user, unknown: "key") == user
    assert struct(user, %{name: "john"}) == %User{name: "john"}
    assert struct(user, name: "other", __struct__: Post) == %User{name: "other"}
  end

  test "struct!/1 and struct!/2" do
    assert struct!(User) == %User{name: "john"}

    user = struct!(User, name: "meg")
    assert user == %User{name: "meg"}

    assert_raise KeyError, fn ->
      struct!(user, unknown: "key")
    end

    assert struct!(user, %{name: "john"}) == %User{name: "john"}
    assert struct!(user, name: "other", __struct__: Post) == %User{name: "other"}
  end

  test "if/2 with invalid keys" do
    error_message =
      "invalid or duplicate keys for if, only \"do\" and an optional \"else\" are permitted"

    assert_raise ArgumentError, error_message, fn ->
      Code.eval_string("if true, foo: 7")
    end

    assert_raise ArgumentError, error_message, fn ->
      Code.eval_string("if true, do: 6, boo: 7")
    end

    assert_raise ArgumentError, error_message, fn ->
      Code.eval_string("if true, do: 7, do: 6")
    end

    assert_raise ArgumentError, error_message, fn ->
      Code.eval_string("if true, do: 8, else: 7, else: 6")
    end

    assert_raise ArgumentError, error_message, fn ->
      Code.eval_string("if true, else: 6")
    end

    assert_raise ArgumentError, error_message, fn ->
      Code.eval_string("if true, []")
    end
  end

  test "unless/2 with invalid keys" do
    error_message =
      "invalid or duplicate keys for unless, only \"do\" " <>
        "and an optional \"else\" are permitted"

    assert_raise ArgumentError, error_message, fn ->
      Code.eval_string("unless true, foo: 7")
    end

    assert_raise ArgumentError, error_message, fn ->
      Code.eval_string("unless true, do: 6, boo: 7")
    end

    assert_raise ArgumentError, error_message, fn ->
      Code.eval_string("unless true, do: 7, do: 6")
    end

    assert_raise ArgumentError, error_message, fn ->
      Code.eval_string("unless true, do: 8, else: 7, else: 6")
    end

    assert_raise ArgumentError, error_message, fn ->
      Code.eval_string("unless true, else: 6")
    end

    assert_raise ArgumentError, error_message, fn ->
      Code.eval_string("unless true, []")
    end
  end

  test "and/2" do
    assert (true and false) == false
    assert (true and true) == true
    assert (true and 0) == 0
    assert (false and false) == false
    assert (false and true) == false
    assert (false and 0) == false
    assert (false and raise("oops")) == false
    assert ((x = Process.get(:unused, true)) and not x) == false
    assert_raise BadBooleanError, fn -> Process.get(:unused, 0) and 1 end
  end

  test "or/2" do
    assert (true or false) == true
    assert (true or true) == true
    assert (true or 0) == true
    assert (true or raise("foo")) == true
    assert (false or false) == false
    assert (false or true) == true
    assert (false or 0) == 0
    assert ((x = Process.get(:unused, false)) or not x) == true
    assert_raise BadBooleanError, fn -> Process.get(:unused, 0) or 1 end
  end

  defp delegate_is_struct(arg), do: is_struct(arg)

  defp guarded_is_struct(arg) when is_struct(arg), do: true
  defp guarded_is_struct(_arg), do: false

  defp struct_or_map?(arg) when is_struct(arg) or is_map(arg), do: true
  defp struct_or_map?(_arg), do: false

  test "is_struct/1" do
    assert delegate_is_struct(%{}) == false
    assert delegate_is_struct([]) == false
    assert delegate_is_struct(%Macro.Env{}) == true
    assert delegate_is_struct(%{__struct__: "foo"}) == false
    assert guarded_is_struct(%Macro.Env{}) == true
    assert guarded_is_struct(%{__struct__: "foo"}) == false
    assert guarded_is_struct([]) == false
    assert guarded_is_struct(%{}) == false
  end

  test "is_struct/1 and other match works" do
    assert struct_or_map?(%Macro.Env{}) == true
    assert struct_or_map?(%{}) == true
    assert struct_or_map?(10) == false
  end

  defp delegate_is_struct(arg, name), do: is_struct(arg, name)

  defp guarded_is_struct(arg, name) when is_struct(arg, name), do: true
  defp guarded_is_struct(_arg, _name), do: false

  defp struct_or_map?(arg, name) when is_struct(arg, name) or is_map(arg), do: true
  defp struct_or_map?(_arg, _name), do: false

  test "is_struct/2" do
    assert delegate_is_struct(%{}, Macro.Env) == false
    assert delegate_is_struct([], Macro.Env) == false
    assert delegate_is_struct(%Macro.Env{}, Macro.Env) == true
    assert delegate_is_struct(%Macro.Env{}, URI) == false
    assert guarded_is_struct(%Macro.Env{}, Macro.Env) == true
    assert guarded_is_struct(%Macro.Env{}, URI) == false
    assert guarded_is_struct(%{__struct__: "foo"}, "foo") == false
    assert guarded_is_struct(%{__struct__: "foo"}, Macro.Env) == false
    assert guarded_is_struct([], Macro.Env) == false
    assert guarded_is_struct(%{}, Macro.Env) == false

    assert_raise ArgumentError, "argument error", fn ->
      is_struct(%{}, Process.get(:unused, "not atom"))
    end
  end

  test "is_struct/2 and other match works" do
    assert struct_or_map?(%{}, "foo") == false
    assert struct_or_map?(%{}, Macro.Env) == true
    assert struct_or_map?(%Macro.Env{}, Macro.Env) == true
  end

  defp delegate_is_non_struct_map(arg), do: is_non_struct_map(arg)

  defp guarded_is_non_struct_map(arg) when is_non_struct_map(arg), do: true
  defp guarded_is_non_struct_map(_arg), do: false

  defp non_struct_map_or_struct?(arg) when is_non_struct_map(arg) or is_struct(arg), do: true
  defp non_struct_map_or_struct?(_arg), do: false

  test "is_non_struct_map/1" do
    assert delegate_is_non_struct_map(%{}) == true
    assert delegate_is_non_struct_map([]) == false
    assert delegate_is_non_struct_map(%Macro.Env{}) == false
    assert delegate_is_non_struct_map(%{__struct__: "foo"}) == true
    assert guarded_is_non_struct_map(%Macro.Env{}) == false
    assert guarded_is_non_struct_map(%{__struct__: "foo"}) == true
    assert guarded_is_non_struct_map([]) == false
    assert guarded_is_non_struct_map(%{}) == true
  end

  test "is_non_struct_map/1 and other match works" do
    assert non_struct_map_or_struct?(%Macro.Env{}) == true
    assert non_struct_map_or_struct?(%{}) == true
    assert non_struct_map_or_struct?(10) == false
  end

  defp delegate_is_exception(arg), do: is_exception(arg)

  defp guarded_is_exception(arg) when is_exception(arg), do: true
  defp guarded_is_exception(_arg), do: false

  defp exception_or_map?(arg) when is_exception(arg) or is_map(arg), do: true
  defp exception_or_map?(_arg), do: false

  test "is_exception/1" do
    assert delegate_is_exception(%{}) == false
    assert delegate_is_exception([]) == false
    assert delegate_is_exception(%RuntimeError{}) == true
    assert delegate_is_exception(%{__exception__: "foo"}) == false
    assert guarded_is_exception(%RuntimeError{}) == true
    assert guarded_is_exception(%{__exception__: "foo"}) == false
    assert guarded_is_exception([]) == false
    assert guarded_is_exception(%{}) == false
  end

  test "is_exception/1 and other match works" do
    assert exception_or_map?(%RuntimeError{}) == true
    assert exception_or_map?(%{}) == true
    assert exception_or_map?(10) == false
  end

  defp delegate_is_exception(arg, name), do: is_exception(arg, name)

  defp guarded_is_exception(arg, name) when is_exception(arg, name), do: true
  defp guarded_is_exception(_arg, _name), do: false

  defp exception_or_map?(arg, name) when is_exception(arg, name) or is_map(arg), do: true
  defp exception_or_map?(_arg, _name), do: false

  test "is_exception/2" do
    assert delegate_is_exception(%{}, RuntimeError) == false
    assert delegate_is_exception([], RuntimeError) == false
    assert delegate_is_exception(%RuntimeError{}, RuntimeError) == true
    assert delegate_is_exception(%RuntimeError{}, Macro.Env) == false
    assert guarded_is_exception(%RuntimeError{}, RuntimeError) == true
    assert guarded_is_exception(%RuntimeError{}, Macro.Env) == false
    assert guarded_is_exception(%{__exception__: "foo"}, "foo") == false
    assert guarded_is_exception(%{__exception__: "foo"}, RuntimeError) == false
    assert guarded_is_exception([], RuntimeError) == false
    assert guarded_is_exception(%{}, RuntimeError) == false

    assert_raise ArgumentError, "argument error", fn ->
      delegate_is_exception(%{}, Process.get(:unused, "not atom"))
    end
  end

  test "is_exception/2 and other match works" do
    assert exception_or_map?(%{}, "foo") == false
    assert exception_or_map?(%{}, RuntimeError) == true
    assert exception_or_map?(%RuntimeError{}, RuntimeError) == true
  end

  test "then/2" do
    assert 1 |> then(fn x -> x * 2 end) == 2
  end

  test "if/2 boolean optimization does not leak variables during expansion" do
    if false do
      :ok
    else
      assert Macro.Env.vars(__ENV__) == []
    end
  end

  describe ".." do
    test "returns 0..-1//1" do
      assert (..) == 0..-1//1
    end
  end

  describe "in/2" do
    # This test may take a long time on machine with low resources
    @tag timeout: 120_000
    test "too large list in guards" do
      defmodule TooLargeList do
        @list Enum.map(1..1024, & &1)
        defguard is_value(value) when value in @list
      end
    end

    test "with literals on right side" do
      assert 2 in [1, 2, 3]
      assert 2 in 1..3
      refute 4 in [1, 2, 3]
      refute 4 in 1..3
      refute 2 in []
      refute false in []
      refute true in []

      # make sure optimization still evaluates the left-hand side
      # (do not use assert/refute which handle in/2 differently)
      send(self(), :foo) in []
      assert_received :foo
    end

    test "with expressions on right side" do
      list = [1, 2, 3]
      empty_list = []
      assert 2 in list
      refute 4 in list

      refute 4 in empty_list
      refute false in empty_list
      refute true in empty_list

      assert 2 in [1 | [2, 3]]
      assert 3 in [1 | list]

      some_call = & &1
      refute :x in [1, 2 | some_call.([3, 4])]
      assert :x in [1, 2 | some_call.([3, :x])]

      assert_raise ArgumentError, fn ->
        :x in [1, 2 | some_call.({3, 4})]
      end
    end

    @at_list1 [4, 5]
    @at_range 6..8
    @at_list2 [13, 14]
    def fun_in(x) when x in [0], do: :list
    def fun_in(x) when x in 1..3, do: :range
    def fun_in(x) when x in @at_list1, do: :at_list
    def fun_in(x) when x in @at_range, do: :at_range
    def fun_in(x) when x in [9 | [10, 11]], do: :list_cons
    def fun_in(x) when x in [12 | @at_list2], do: :list_cons_at
    def fun_in(x) when x in 21..15//1, do: raise("oops positive")
    def fun_in(x) when x in 15..21//-1, do: raise("oops negative")
    def fun_in(x) when x in 15..21//2, do: :range_step_2
    def fun_in(x) when x in 15..21//1, do: :range_step_1
    def fun_in(_), do: :none

    test "in function guard" do
      assert fun_in(0) == :list
      assert fun_in(1) == :range
      assert fun_in(2) == :range
      assert fun_in(3) == :range
      assert fun_in(5) == :at_list
      assert fun_in(6) == :at_range
      assert fun_in(7) == :at_range
      assert fun_in(8) == :at_range
      assert fun_in(9) == :list_cons
      assert fun_in(10) == :list_cons
      assert fun_in(11) == :list_cons
      assert fun_in(12) == :list_cons_at
      assert fun_in(13) == :list_cons_at
      assert fun_in(14) == :list_cons_at
      assert fun_in(15) == :range_step_2
      assert fun_in(16) == :range_step_1
      assert fun_in(17) == :range_step_2
      assert fun_in(22) == :none

      assert fun_in(0.0) == :none
      assert fun_in(1.0) == :none
      assert fun_in(2.0) == :none
      assert fun_in(3.0) == :none
      assert fun_in(6.0) == :none
      assert fun_in(7.0) == :none
      assert fun_in(8.0) == :none
      assert fun_in(9.0) == :none
      assert fun_in(10.0) == :none
      assert fun_in(11.0) == :none
      assert fun_in(12.0) == :none
      assert fun_in(13.0) == :none
      assert fun_in(14.0) == :none
      assert fun_in(15.0) == :none
      assert fun_in(16.0) == :none
      assert fun_in(17.0) == :none
    end

    def dynamic_step_in(x, y, z, w) when x in y..z//w, do: true
    def dynamic_step_in(_x, _y, _z, _w), do: false

    test "in dynamic range with step function guard" do
      assert dynamic_step_in(1, 1, 3, 1)
      assert dynamic_step_in(2, 1, 3, 1)
      assert dynamic_step_in(3, 1, 3, 1)

      refute dynamic_step_in(1, 1, 3, -1)
      refute dynamic_step_in(2, 1, 3, -1)
      refute dynamic_step_in(3, 1, 3, -1)

      assert dynamic_step_in(1, 3, 1, -1)
      assert dynamic_step_in(2, 3, 1, -1)
      assert dynamic_step_in(3, 3, 1, -1)

      refute dynamic_step_in(1, 3, 1, 1)
      refute dynamic_step_in(2, 3, 1, 1)
      refute dynamic_step_in(3, 3, 1, 1)

      assert dynamic_step_in(1, 1, 3, 2)
      refute dynamic_step_in(2, 1, 3, 2)
      assert dynamic_step_in(3, 1, 3, 2)
      assert dynamic_step_in(3, 1, 4, 2)
      refute dynamic_step_in(4, 1, 4, 2)
    end

    defmacrop case_in(x, y) do
      quote do
        case 0 do
          _ when unquote(x) in unquote(y) -> true
          _ -> false
        end
      end
    end

    test "in case guard" do
      assert case_in(1, [1, 2, 3]) == true
      assert case_in(1, 1..3) == true
      assert case_in(2, 1..3) == true
      assert case_in(3, 1..3) == true
      assert case_in(-3, -1..-3//-1) == true
    end

    def map_dot(map) when map.field, do: true
    def map_dot(_other), do: false

    test "map dot guard" do
      refute map_dot(:foo)
      refute map_dot(%{})
      refute map_dot(%{field: false})
      assert map_dot(%{field: true})
    end

    test "performs all side-effects in order" do
      assert 1 in [1, send(self(), 2)]
      assert_received 2

      assert 1 in [1 | send(self(), [2])]
      assert_received [2]

      assert 2 in [1 | send(self(), [2])]
      assert_received [2]

      send(self(), :first) in send(self(), [:first, :second, :third])
      assert Process.info(self(), :messages) == {:messages, [:first, [:first, :second, :third]]}
      assert_received :first
      assert_received [:first, :second, :third]

      send(self(), 0) in send(self(), -2)..send(self(), 2)//send(self(), 1)
      assert Process.info(self(), :messages) == {:messages, [0, -2, 2, 1]}
    end

    test "preserves variable semantics" do
      a = 1
      assert 1 in [a = 2, a]
      # silence unused var warning
      _ = a
    end

    test "in module body" do
      defmodule InSample do
        @foo [:a, :b]
        true = :a in @foo
      end
    after
      purge(InSample)
    end

    test "inside and/2" do
      response = Process.get(:unused, %{code: 200})

      if is_map(response) and response.code in 200..299 do
        :pass
      end

      # This module definition copies internal variable
      # defined during in/2 expansion.
      Module.create(InVarCopy, nil, __ENV__)
      purge(InVarCopy)
    end

    test "with a non-literal non-escaped compile-time range in guards" do
      message = ~r"found unescaped value on the right side of in/2: 1..3"

      assert_eval_raise(ArgumentError, message, """
      defmodule InErrors do
        range = 1..3
        def foo(x) when x in unquote(range), do: :ok
      end
      """)
    end

    test "with a non-compile-time range in guards" do
      message = ~r/invalid right argument for operator "in", .* got: :hello/

      assert_eval_raise(ArgumentError, message, """
      defmodule InErrors do
        def foo(x) when x in :hello, do: :ok
      end
      """)
    end

    test "with a non-compile-time list cons in guards" do
      message = ~r/invalid right argument for operator "in", .* got: \[1 | list\(\)\]/

      assert_eval_raise(ArgumentError, message, """
      defmodule InErrors do
        def list, do: [1]
        def foo(x) when x in [1 | list()], do: :ok
      end
      """)
    end

    test "with a compile-time non-list in tail in guards" do
      message = ~r/invalid right argument for operator "in", .* got: \[1 | 1..3\]/

      assert_eval_raise(ArgumentError, message, """
      defmodule InErrors do
        def foo(x) when x in [1 | 1..3], do: :ok
      end
      """)
    end

    test "hoists variables and keeps order" do
      # Ranges
      result = expand_to_string(quote(do: rand() in 1..2))
      assert result =~ "var = rand()"

      result = expand_to_string(quote(do: var in 1..2), :guard)

      assert result =~ """
             :erlang.andalso(
               :erlang.is_integer(var),
               :erlang.andalso(:erlang.>=(var, 1), :erlang.\"=<\"(var, 2))
             )\
             """

      # Empty list
      assert expand_to_string(quote(do: :x in [])) =~ ":lists.member(:x, [])"
      assert expand_to_string(quote(do: :x in []), :guard) == "false"

      # Lists
      result = expand_to_string(quote(do: rand() in [1, 2]))
      assert result =~ ":lists.member(rand(), [1, 2]"
    end

    test "is optimized" do
      assert expand_to_string(quote(do: foo in []), :guard) ==
               "false"

      assert expand_to_string(quote(do: foo in [1, 2, 3]), :guard) == """
             :erlang.orelse(
               :erlang.orelse(:erlang.\"=:=\"(foo, 1), :erlang.\"=:=\"(foo, 2)),
               :erlang.\"=:=\"(foo, 3)
             )\
             """

      assert expand_to_string(quote(do: foo in 0..1), :guard) == """
             :erlang.andalso(
               :erlang.is_integer(foo),
               :erlang.andalso(:erlang.>=(foo, 0), :erlang.\"=<\"(foo, 1))
             )\
             """

      assert expand_to_string(quote(do: foo in -1..0), :guard) == """
             :erlang.andalso(
               :erlang.is_integer(foo),
               :erlang.andalso(:erlang.>=(foo, -1), :erlang.\"=<\"(foo, 0))
             )\
             """

      assert expand_to_string(quote(do: foo in 1..1), :guard) ==
               ":erlang.\"=:=\"(foo, 1)"

      assert expand_to_string(quote(do: 2 in 1..3), :guard) ==
               ":erlang.andalso(:erlang.is_integer(2), :erlang.andalso(:erlang.>=(2, 1), :erlang.\"=<\"(2, 3)))"
    end

    defp expand_to_string(ast, environment_or_context \\ __ENV__)

    defp expand_to_string(ast, context) when is_atom(context) do
      expand_to_string(ast, %{__ENV__ | context: context})
    end

    defp expand_to_string(ast, environment) do
      ast
      |> Macro.prewalk(&Macro.expand(&1, environment))
      |> Macro.to_string()
    end
  end

  describe "__info__" do
    test ":macros" do
      assert {:in, 2} in Kernel.__info__(:macros)
    end

    test ":functions" do
      refute {:__info__, 1} in Kernel.__info__(:functions)
    end

    test ":struct" do
      assert Kernel.__info__(:struct) == nil
      assert [%{field: :scheme, default: nil} | _] = URI.__info__(:struct)
    end

    test "others" do
      assert Kernel.__info__(:module) == Kernel
      assert is_list(Kernel.__info__(:compile))
      assert is_list(Kernel.__info__(:attributes))
    end
  end

  describe "@" do
    test "setting attribute with do-block" do
      exception =
        catch_error(
          defmodule UpcaseAttrSample do
            @foo quote do
              :ok
            end
          end
        )

      assert exception.message =~ "expected 0 or 1 argument for @foo, got 2"
      assert exception.message =~ "You probably want to wrap the argument value in parentheses"
    end

    test "setting attribute with uppercase" do
      message = "module attributes set via @ cannot start with an uppercase letter"

      assert_raise ArgumentError, message, fn ->
        defmodule UpcaseAttrSample do
          @Upper
        end
      end
    end

    test "matching attribute" do
      assert_raise ArgumentError, ~r"invalid usage of module attributes", fn ->
        defmodule MatchAttributeInModule do
          @foo = 42
        end
      end

      assert_raise ArgumentError, ~r"invalid usage of module attributes", fn ->
        defmodule MatchAttributeInModule do
          @foo 16
          <<_::@foo>> = "ab"
        end
      end

      assert_raise ArgumentError, ~r"invalid usage of module attributes", fn ->
        defmodule MatchAttributeInModule do
          @foo 16
          <<_::size(@foo)>> = "ab"
        end
      end
    end
  end

  describe "defdelegate" do
    defdelegate my_flatten(list), to: List, as: :flatten

    dynamic = :dynamic_flatten
    defdelegate unquote(dynamic)(list), to: List, as: :flatten

    test "dispatches to delegated functions" do
      assert my_flatten([[1]]) == [1]
    end

    test "with unquote" do
      assert dynamic_flatten([[1]]) == [1]
    end

    test "raises with non-variable arguments" do
      assert_raise ArgumentError,
                   "guards are not allowed in defdelegate/2, got: when is_list(term) or is_binary(term)",
                   fn ->
                     string = """
                     defmodule IntDelegateWithGuards do
                       defdelegate foo(term) when is_list(term) or is_binary(term), to: List
                     end
                     """

                     Code.eval_string(string, [], __ENV__)
                   end

      msg = "defdelegate/2 only accepts function parameters, got: 1"

      assert_raise ArgumentError, msg, fn ->
        string = """
        defmodule IntDelegate do
          defdelegate foo(1), to: List
        end
        """

        Code.eval_string(string, [], __ENV__)
      end

      assert_raise ArgumentError, msg, fn ->
        string = """
        defmodule IntOptionDelegate do
          defdelegate foo(1 \\\\ 1), to: List
        end
        """

        Code.eval_string(string, [], __ENV__)
      end
    end

    test "raises when :to targeting the delegating module is given without the :as option" do
      assert_raise ArgumentError,
                   ~r/defdelegate function is calling itself, which will lead to an infinite loop. You should either change the value of the :to option or specify the :as option/,
                   fn ->
                     defmodule ImplAttributes do
                       defdelegate foo(), to: __MODULE__
                     end
                   end
    end

    defdelegate my_reverse(list \\ []), to: :lists, as: :reverse
    defdelegate my_get(map \\ %{}, key, default \\ ""), to: Map, as: :get

    test "accepts variable with optional arguments" do
      assert my_reverse() == []
      assert my_reverse([1, 2, 3]) == [3, 2, 1]

      assert my_get("foo") == ""
      assert my_get(%{}, "foo") == ""
      assert my_get(%{"foo" => "bar"}, "foo") == "bar"
      assert my_get(%{}, "foo", "not_found") == "not_found"
    end
  end

  describe "defmodule" do
    test "expects atoms as module names" do
      msg = ~r"invalid module name: 3"

      assert_raise ArgumentError, msg, fn ->
        defmodule 1 + 2, do: :ok
      end
    end

    test "does not accept special atoms as module names" do
      special_atoms = [nil, true, false]

      Enum.each(special_atoms, fn special_atom ->
        msg = ~r"invalid module name: #{inspect(special_atom)}"

        assert_raise ArgumentError, msg, fn ->
          defmodule special_atom, do: :ok
        end
      end)
    end

    test "does not accept slashes in module names" do
      assert_raise ArgumentError, ~r(invalid module name: :"foo/bar"), fn ->
        defmodule :"foo/bar", do: :ok
      end

      assert_raise ArgumentError, ~r(invalid module name: :"foo\\\\bar"), fn ->
        defmodule :"foo\\bar", do: :ok
      end
    end
  end

  describe "access" do
    defmodule StructAccess do
      defstruct [:foo, :bar]
    end

    test "get_in/1" do
      users = %{"john" => %{age: 27}, :meg => %{age: 23}}
      assert get_in(users["john"][:age]) == 27
      assert get_in(users["dave"][:age]) == nil
      assert get_in(users["john"].age) == 27
      assert get_in(users["dave"].age) == nil
      assert get_in(users.meg[:age]) == 23
      assert get_in(users.meg.age) == 23

      is_nil = nil
      assert get_in(is_nil.age) == nil

      assert_raise KeyError, ~r"key :unknown not found", fn -> get_in(users.unknown) end
      assert_raise KeyError, ~r"key :unknown not found", fn -> get_in(users.meg.unknown) end
    end

    test "get_in/2" do
      users = %{"john" => %{age: 27}, "meg" => %{age: 23}}
      assert get_in(users, ["john", :age]) == 27
      assert get_in(users, ["dave", :age]) == nil
      assert get_in(nil, ["john", :age]) == nil

      map = %{"fruits" => ["banana", "apple", "orange"]}
      assert get_in(map, ["fruits", by_index(0)]) == "banana"
      assert get_in(map, ["fruits", by_index(3)]) == nil
      assert get_in(map, ["unknown", by_index(3)]) == nil
    end

    test "put_in/3" do
      users = %{"john" => %{age: 27}, "meg" => %{age: 23}}

      assert put_in(users, ["john", :age], 28) == %{"john" => %{age: 28}, "meg" => %{age: 23}}

      assert_raise ArgumentError, "could not put/update key \"john\" on a nil value", fn ->
        put_in(nil, ["john", :age], 28)
      end
    end

    test "put_in/2" do
      users = %{"john" => %{age: 27}, "meg" => %{age: 23}}

      assert put_in(users["john"][:age], 28) == %{"john" => %{age: 28}, "meg" => %{age: 23}}

      assert put_in(users["john"].age, 28) == %{"john" => %{age: 28}, "meg" => %{age: 23}}

      struct = %StructAccess{foo: %StructAccess{}}

      assert put_in(struct.foo.bar, :baz) ==
               %StructAccess{bar: nil, foo: %StructAccess{bar: :baz, foo: nil}}

      assert_raise BadMapError, fn ->
        put_in(users["dave"].age, 19)
      end

      assert_raise KeyError, fn ->
        put_in(users["meg"].unknown, "value")
      end
    end

    test "update_in/3" do
      users = %{"john" => %{age: 27}, "meg" => %{age: 23}}

      assert update_in(users, ["john", :age], &(&1 + 1)) ==
               %{"john" => %{age: 28}, "meg" => %{age: 23}}

      assert_raise ArgumentError, "could not put/update key \"john\" on a nil value", fn ->
        update_in(nil, ["john", :age], fn _ -> %{} end)
      end

      assert_raise UndefinedFunctionError, fn ->
        pop_in(struct(Sample, []), [:name])
      end
    end

    test "update_in/2" do
      users = %{"john" => %{age: 27}, "meg" => %{age: 23}}

      assert update_in(users["john"][:age], &(&1 + 1)) ==
               %{"john" => %{age: 28}, "meg" => %{age: 23}}

      assert update_in(users["john"].age, &(&1 + 1)) ==
               %{"john" => %{age: 28}, "meg" => %{age: 23}}

      struct = %StructAccess{foo: %StructAccess{bar: 41}}

      assert update_in(struct.foo.bar, &(&1 + 1)) ==
               %StructAccess{bar: nil, foo: %StructAccess{bar: 42, foo: nil}}

      assert_raise BadMapError, fn ->
        update_in(users["dave"].age, &(&1 + 1))
      end

      assert_raise KeyError, fn ->
        put_in(users["meg"].unknown, &(&1 + 1))
      end
    end

    test "get_and_update_in/3" do
      users = %{"john" => %{age: 27}, "meg" => %{age: 23}}

      assert get_and_update_in(users, ["john", :age], &{&1, &1 + 1}) ==
               {27, %{"john" => %{age: 28}, "meg" => %{age: 23}}}

      map = %{"fruits" => ["banana", "apple", "orange"]}

      assert get_and_update_in(map, ["fruits", by_index(0)], &{&1, String.reverse(&1)}) ==
               {"banana", %{"fruits" => ["ananab", "apple", "orange"]}}

      assert get_and_update_in(map, ["fruits", by_index(3)], &{&1, &1}) ==
               {nil, %{"fruits" => ["banana", "apple", "orange"]}}

      assert get_and_update_in(map, ["unknown", by_index(3)], &{&1, []}) ==
               {:oops, %{"fruits" => ["banana", "apple", "orange"], "unknown" => []}}
    end

    test "get_and_update_in/2" do
      users = %{"john" => %{age: 27}, "meg" => %{age: 23}}

      assert get_and_update_in(users["john"].age, &{&1, &1 + 1}) ==
               {27, %{"john" => %{age: 28}, "meg" => %{age: 23}}}

      struct = %StructAccess{foo: %StructAccess{bar: 41}}

      assert get_and_update_in(struct.foo.bar, &{&1, &1 + 1}) ==
               {41, %StructAccess{bar: nil, foo: %StructAccess{bar: 42, foo: nil}}}

      assert_raise ArgumentError, "could not put/update key \"john\" on a nil value", fn ->
        get_and_update_in(nil["john"][:age], fn nil -> {:ok, 28} end)
      end

      assert_raise BadMapError, fn ->
        get_and_update_in(users["dave"].age, &{&1, &1 + 1})
      end

      assert_raise KeyError, fn ->
        get_and_update_in(users["meg"].unknown, &{&1, &1 + 1})
      end
    end

    test "pop_in/2" do
      users = %{"john" => %{age: 27}, "meg" => %{age: 23}}

      assert pop_in(users, ["john", :age]) ==
               {27, %{"john" => %{}, "meg" => %{age: 23}}}

      assert pop_in(users, ["bob", :age]) ==
               {nil, %{"john" => %{age: 27}, "meg" => %{age: 23}}}

      assert pop_in([], [:foo, :bar]) ==
               {nil, []}
    end

    test "pop_in/2 with paths" do
      map = %{"fruits" => ["banana", "apple", "orange"]}

      assert pop_in(map, ["fruits", by_index(0)]) ==
               {"banana", %{"fruits" => ["apple", "orange"]}}

      assert pop_in(map, ["fruits", by_index(3)]) == {nil, map}

      map = %{"fruits" => [%{name: "banana"}, %{name: "apple"}]}

      assert pop_in(map, ["fruits", by_index(0), :name]) ==
               {"banana", %{"fruits" => [%{}, %{name: "apple"}]}}

      assert pop_in(map, ["fruits", by_index(3), :name]) == {nil, map}
    end

    test "pop_in/1" do
      users = %{"john" => %{age: 27}, "meg" => %{age: 23}}

      assert pop_in(users["john"]) == {%{age: 27}, %{"meg" => %{age: 23}}}

      assert pop_in(users["john"][:age]) == {27, %{"john" => %{}, "meg" => %{age: 23}}}
      assert pop_in(users["john"][:name]) == {nil, %{"john" => %{age: 27}, "meg" => %{age: 23}}}
      assert pop_in(users["bob"][:age]) == {nil, %{"john" => %{age: 27}, "meg" => %{age: 23}}}

      users = %{john: [age: 27], meg: [age: 23]}

      assert pop_in(users.john[:age]) == {27, %{john: [], meg: [age: 23]}}
      assert pop_in(users.john[:name]) == {nil, %{john: [age: 27], meg: [age: 23]}}

      assert pop_in([][:foo][:bar]) == {nil, []}
      assert_raise KeyError, fn -> pop_in(users.bob[:age]) end
    end

    test "pop_in/1,2 with nils" do
      users = %{"john" => nil, "meg" => %{age: 23}}
      assert pop_in(users["john"][:age]) == {nil, %{"meg" => %{age: 23}}}
      assert pop_in(users, ["john", :age]) == {nil, %{"meg" => %{age: 23}}}

      users = %{john: nil, meg: %{age: 23}}
      assert pop_in(users.john[:age]) == {nil, %{john: nil, meg: %{age: 23}}}
      assert pop_in(users, [:john, :age]) == {nil, %{meg: %{age: 23}}}

      x = nil
      assert_raise ArgumentError, fn -> pop_in(x["john"][:age]) end
      assert_raise ArgumentError, fn -> pop_in(nil["john"][:age]) end
      assert_raise ArgumentError, fn -> pop_in(nil, ["john", :age]) end
    end

    test "with dynamic paths" do
      map = empty_map()

      assert put_in(map[:foo], "bar") == %{foo: "bar"}
      assert put_in(empty_map()[:foo], "bar") == %{foo: "bar"}
      assert put_in(KernelTest.empty_map()[:foo], "bar") == %{foo: "bar"}
      assert put_in(__MODULE__.empty_map()[:foo], "bar") == %{foo: "bar"}

      assert_raise ArgumentError, ~r"access at least one element,", fn ->
        Code.eval_quoted(quote(do: put_in(map, "bar")), [])
      end

      assert_raise ArgumentError, ~r"must start with a variable, local or remote call", fn ->
        Code.eval_quoted(quote(do: put_in(map.foo(1, 2)[:bar], "baz")), [])
      end
    end

    def by_index(index) do
      fn
        :get, nil, _next ->
          raise "won't be invoked"

        :get, data, next ->
          next.(Enum.at(data, index))

        :get_and_update, nil, next ->
          next.(:oops)

        :get_and_update, data, next ->
          current = Enum.at(data, index)

          case next.(current) do
            {get, update} -> {get, List.replace_at(data, index, update)}
            :pop -> {current, List.delete_at(data, index)}
          end
      end
    end
  end

  describe "pipeline" do
    test "simple" do
      assert [1, [2], 3] |> List.flatten() == [1, 2, 3]
    end

    test "nested" do
      assert [1, [2], 3] |> List.flatten() |> Enum.map(&(&1 * 2)) == [2, 4, 6]
    end

    test "local call" do
      assert [1, [2], 3] |> List.flatten() |> local() == [2, 4, 6]
    end

    test "with capture" do
      assert Enum.map([1, 2, 3], &(&1 |> twice() |> twice())) == [4, 8, 12]
    end

    test "with anonymous functions" do
      assert 1 |> (&(&1 * 2)).() == 2
      assert [1] |> (&hd(&1)).() == 1
    end

    test "reverse associativity" do
      assert [1, [2], 3] |> (List.flatten() |> Enum.map(&(&1 * 2))) == [2, 4, 6]
    end

    defp twice(a), do: a * 2

    defp local(list) do
      Enum.map(list, &(&1 * 2))
    end
  end

  describe "destructure" do
    test "less args" do
      destructure [x, y, z], [1, 2, 3, 4, 5]
      assert x == 1
      assert y == 2
      assert z == 3
    end

    test "more args" do
      destructure [a, b, c, d, e], [1, 2, 3]
      assert a == 1
      assert b == 2
      assert c == 3
      assert d == nil
      assert e == nil
    end

    test "equal args" do
      destructure [a, b, c], [1, 2, 3]
      assert a == 1
      assert b == 2
      assert c == 3
    end

    test "no values" do
      destructure [a, b, c], []
      assert a == nil
      assert b == nil
      assert c == nil
    end

    test "works as match" do
      destructure [1, b, _], [1, 2, 3]
      assert b == 2
    end

    test "nil values" do
      destructure [a, b, c], a_nil()
      assert a == nil
      assert b == nil
      assert c == nil
    end

    test "invalid match" do
      a = List.first([3])

      assert_raise MatchError, fn ->
        destructure [^a, _b, _c], a_list()
      end
    end

    defp a_list, do: [1, 2, 3]
    defp a_nil, do: nil
  end

  describe "use/2" do
    import ExUnit.CaptureIO

    defmodule SampleA do
      defmacro __using__(opts) do
        prefix = Keyword.get(opts, :prefix, "")
        IO.puts(prefix <> "A")
      end
    end

    defmodule SampleB do
      defmacro __using__(_) do
        IO.puts("B")
      end
    end

    test "invalid argument is literal" do
      message = "invalid arguments for use, expected a compile time atom or alias, got: 42"

      assert_raise ArgumentError, message, fn ->
        Code.eval_string("use 42")
      end
    end

    test "invalid argument is variable" do
      message = "invalid arguments for use, expected a compile time atom or alias, got: variable"

      assert_raise ArgumentError, message, fn ->
        Code.eval_string("use variable")
      end
    end

    test "multi-call" do
      assert capture_io(fn ->
               Code.eval_string("use KernelTest.{SampleA, SampleB,}", [], __ENV__)
             end) == "A\nB\n"
    end

    test "multi-call with options" do
      assert capture_io(fn ->
               Code.eval_string(~S|use KernelTest.{SampleA}, prefix: "-"|, [], __ENV__)
             end) == "-A\n"
    end

    test "multi-call with unquote" do
      assert capture_io(fn ->
               string = """
               defmodule TestMod do
                 def main() do
                   use KernelTest.{SampleB, unquote(:SampleA)}
                 end
               end
               """

               Code.eval_string(string, [], __ENV__)
             end) == "B\nA\n"
    after
      purge(KernelTest.TestMod)
    end
  end

  test "is_map_key/2" do
    assert is_map_key(Map.new([]), :a) == false
    assert is_map_key(Map.new(b: 1), :a) == false
    assert is_map_key(Map.new(a: 1), :a) == true

    assert_raise BadMapError, fn ->
      is_map_key(Process.get(:unused, []), :a)
    end

    case Map.new(a: 1) do
      map when is_map_key(map, :a) -> true
      _ -> flunk("invalid guard")
    end
  end

  test "tap/1" do
    import ExUnit.CaptureIO

    assert capture_io(fn ->
             tap("foo", &IO.puts/1)
           end) == "foo\n"

    assert 1 = tap(1, fn x -> x + 1 end)
  end

  test "tl/1" do
    assert tl([:one]) == []
    assert tl([1, 2, 3]) == [2, 3]
    assert_raise ArgumentError, fn -> tl(Process.get(:unused, [])) end

    assert tl([:a | :b]) == :b
    assert tl([:a, :b | :c]) == [:b | :c]
  end

  test "hd/1" do
    assert hd([1, 2, 3, 4]) == 1
    assert_raise ArgumentError, fn -> hd(Process.get(:unused, [])) end
    assert hd([1 | 2]) == 1
  end

  test "floor/1" do
    assert floor(1) === 1
    assert floor(1.0) === 1
    assert floor(0) === 0
    assert floor(0.0) === 0
    assert floor(-0.0) === 0
    assert floor(1.123) === 1
    assert floor(-10.123) === -11
    assert floor(-10) === -10
    assert floor(-10.0) === -10

    assert match?(x when floor(x) == 0, 0.2)
  end

  test "ceil/1" do
    assert ceil(1) === 1
    assert ceil(1.0) === 1
    assert ceil(0) === 0
    assert ceil(0.0) === 0
    assert ceil(-0.0) === 0
    assert ceil(1.123) === 2
    assert ceil(-10.123) === -10
    assert ceil(-10) === -10
    assert ceil(-10.0) === -10

    assert match?(x when ceil(x) == 1, 0.2)
  end

  test "binary_slice/2" do
    assert binary_slice("abc", -1..0) == ""
    assert binary_slice("abc", -5..-5) == ""
    assert binary_slice("x", 0..0//2) == "x"
    assert binary_slice("abcde", 1..3//2) == "bd"
  end

  test "sigil_U/2" do
    assert ~U[2015-01-13 13:00:07.123Z] == %DateTime{
             calendar: Calendar.ISO,
             day: 13,
             hour: 13,
             microsecond: {123_000, 3},
             minute: 0,
             month: 1,
             second: 7,
             std_offset: 0,
             time_zone: "Etc/UTC",
             utc_offset: 0,
             year: 2015,
             zone_abbr: "UTC"
           }

    assert_raise ArgumentError, ~r"reason: :invalid_format", fn ->
      Code.eval_string(~s{~U[2015-01-13 13:00]})
    end

    assert_raise ArgumentError, ~r"reason: :invalid_format", fn ->
      Code.eval_string(~s{~U[20150113 130007Z]})
    end

    assert_raise ArgumentError, ~r"reason: :missing_offset", fn ->
      Code.eval_string(~s{~U[2015-01-13 13:00:07]})
    end

    assert_raise ArgumentError, ~r"reason: :non_utc_offset", fn ->
      Code.eval_string(~s{~U[2015-01-13 13:00:07+00:30]})
    end
  end

  describe "dbg/2" do
    import ExUnit.CaptureIO

    test "prints the given expression and returns its value" do
      output = capture_io(fn -> assert dbg(List.duplicate(:foo, 3)) == [:foo, :foo, :foo] end)
      assert output =~ "kernel_test.exs"
      assert output =~ "KernelTest"
      assert output =~ "List"
      assert output =~ "duplicate"
      assert output =~ ":foo"
      assert output =~ "3"
    end

    test "prints the given expression with complex options" do
      output = capture_io(fn -> assert dbg(123, [] ++ []) == 123 end)
      assert output =~ "kernel_test.exs"
    end

    test "doesn't print any colors if :syntax_colors is []" do
      output =
        capture_io(fn ->
          assert dbg(List.duplicate(:foo, 3), syntax_colors: []) == [:foo, :foo, :foo]
        end)

      assert output =~ "kernel_test.exs"
      assert output =~ "KernelTest."
      assert output =~ "List.duplicate(:foo, 3)"
      assert output =~ "[:foo, :foo, :foo]"
      refute output =~ "\\e["
    end

    test "prints binding() if no arguments are given" do
      my_var = 1
      my_other_var = :foo

      output = capture_io(fn -> dbg() end)

      assert output =~ "binding()"
      assert output =~ "my_var:"
      assert output =~ "my_other_var:"
    end

    test "is not allowed in guards" do
      message = "invalid expression in guard, dbg is not allowed in guards"

      assert_raise ArgumentError, Regex.compile!(message), fn ->
        defmodule DbgGuard do
          def dbg_guard() when dbg(1), do: true
        end
      end
    end

    test "is not allowed in pattern matches" do
      message = "invalid expression in match, dbg is not allowed in patterns"

      assert_eval_raise(ArgumentError, Regex.compile!(message), """
      {:ok, dbg()} = make_ref()
      """)
    end
  end

  describe "to_timeout/1" do
    test "works with keyword lists" do
      assert to_timeout(hour: 2) == 1000 * 60 * 60 * 2
      assert to_timeout(minute: 74) == 1000 * 60 * 74
      assert to_timeout(second: 1293) == 1_293_000
      assert to_timeout(millisecond: 1_234_123) == 1_234_123

      assert to_timeout(hour: 2, minute: 30) == 1000 * 60 * 60 * 2 + 1000 * 60 * 30
      assert to_timeout(minute: 30, hour: 2) == 1000 * 60 * 60 * 2 + 1000 * 60 * 30
      assert to_timeout(minute: 74, second: 30) == 1000 * 60 * 74 + 1000 * 30
    end

    test "raises on invalid values with keyword lists" do
      for unit <- [:hour, :minute, :second, :millisecond],
          value <- [-1, 1.0, :not_an_int] do
        message =
          "timeout component #{inspect(unit)} must be a non-negative integer, " <>
            "got: #{inspect(value)}"

        assert_raise ArgumentError, message, fn -> to_timeout([{unit, value}]) end
      end
    end

    test "raises on invalid keys with keyword lists" do
      message =
        "timeout component :not_a_unit is not a valid timeout component, valid values are: " <>
          ":week, :day, :hour, :minute, :second, :millisecond"

      assert_raise ArgumentError, message, fn -> to_timeout(minute: 3, not_a_unit: 1) end
    end

    test "raises on duplicated components with keyword lists" do
      assert_raise ArgumentError, "timeout component :minute is duplicated", fn ->
        to_timeout(minute: 3, hour: 2, minute: 1)
      end
    end

    test "works with durations" do
      assert to_timeout(Duration.new!(hour: 2)) == 1000 * 60 * 60 * 2
      assert to_timeout(Duration.new!(minute: 74)) == 1000 * 60 * 74
      assert to_timeout(Duration.new!(second: 1293)) == 1_293_000
      assert to_timeout(Duration.new!(microsecond: {1_234_123, 4})) == 1_234

      assert to_timeout(Duration.new!(hour: 2, minute: 30)) == 1000 * 60 * 60 * 2 + 1000 * 60 * 30
      assert to_timeout(Duration.new!(minute: 30, hour: 2)) == 1000 * 60 * 60 * 2 + 1000 * 60 * 30
      assert to_timeout(Duration.new!(minute: 74, second: 30)) == 1000 * 60 * 74 + 1000 * 30
    end

    test "raises on durations with non-zero months or days" do
      message = "duration with a non-zero month cannot be reliably converted to timeouts"

      assert_raise ArgumentError, message, fn ->
        to_timeout(Duration.new!(month: 3))
      end

      message = "duration with a non-zero year cannot be reliably converted to timeouts"

      assert_raise ArgumentError, message, fn ->
        to_timeout(Duration.new!(year: 1))
      end
    end

    test "raises on durations that result in a negative timeout" do
      assert_raise ArgumentError,
                   ~r"duration must be positive",
                   fn -> to_timeout(Duration.new!(second: -1)) end

      assert_raise ArgumentError,
                   ~r"duration must be positive",
                   fn -> to_timeout(Duration.new!(hour: 1, minute: -61)) end
    end

    test "works with timeouts" do
      assert to_timeout(1_000) == 1_000
      assert to_timeout(0) == 0
      assert to_timeout(:infinity) == :infinity
    end
  end
end
