require 'base_test_helper'

describe GLib::SizedArray do
  describe "::wrap" do
    it "takes a type, size and pointer and returns a GLib::SizedArray wrapping them" do
      mock(ptr = Object.new).null? { false }
      sarr = GLib::SizedArray.wrap :gint32, 3, ptr
      assert_instance_of GLib::SizedArray, sarr
      assert_equal ptr, sarr.to_ptr
      assert_equal 3, sarr.size
      assert_equal :gint32, sarr.element_type
    end

    it "returns nil if the wrapped pointer is null" do
      mock(ptr = Object.new).null? { true }
      sarr = GLib::SizedArray.wrap :gint32, 3, ptr
      sarr.must_be_nil
    end
  end

  describe "#each" do
    it "yields each element" do
      ary = ["one", "two", "three"]
      ptrs = ary.map {|a| FFI::MemoryPointer.from_string(a)}
      ptrs << nil
      block = FFI::MemoryPointer.new(:pointer, ptrs.length)
      block.write_array_of_pointer ptrs

      sarr = GLib::SizedArray.new :utf8, 3, block
      arr = []
      sarr.each do |str|
        arr << str
      end
      assert_equal ["one", "two", "three"], arr
    end
  end

  describe "::from" do
    context "from a Ruby array" do
      it "creates a GLib::SizedArray with the same elements" do
        arr = GLib::SizedArray.from :gint32, 3, [3, 2, 1]
        arr.must_be_instance_of GLib::SizedArray
        assert_equal [3, 2, 1], arr.to_a
      end

      it "raises an error if the array has the wrong number of elements" do
        lambda { GLib::SizedArray.from :gint32, 4, [3, 2, 1] }.must_raise ArgumentError
      end

      it "uses the array's size if passed -1 as the size" do
        arr = GLib::SizedArray.from :gint32, -1, [3, 2, 1]
        arr.size.must_equal 3
      end
    end

    context "from a GLib::SizedArray" do
      it "return its argument" do
        arr = GLib::SizedArray.from :gint32, 3, [3, 2, 1]
        arr2 = GLib::SizedArray.from :gint32, 3, arr
        assert_equal arr, arr2
      end

      it "raises an error if the argument has the wrong number of elements" do
        arr = GLib::SizedArray.from :gint32, 3, [3, 2, 1]
        lambda { GLib::SizedArray.from :gint32, 4, arr }.must_raise ArgumentError
      end
    end

    it "returns nil when passed nil" do
      arr = GLib::SizedArray.from :gint32, 0, nil
      arr.must_be_nil
    end

    it "wraps its argument if given a pointer" do
      arr = GLib::SizedArray.from :gint32, 3, [3, 2, 1]
      arr2 = GLib::SizedArray.from :gint32, 3, arr.to_ptr
      assert_instance_of GLib::SizedArray, arr2
      refute_equal arr, arr2
      assert_equal arr.to_a, arr2.to_a
    end
  end

  it "includes Enumerable" do
    GLib::SizedArray.must_include Enumerable
  end
end