describe :env_store, shared: true do
  before :each do
    @saved_foo = ENV["foo"]
  end

  after :each do
    ENV["foo"] = @saved_foo
  end

  it "sets the environment variable to the given value" do
    ENV.send(@method, "foo", "bar")
    ENV["foo"].should == "bar"
  end

  it "returns the value" do
    value = "bar"
    ENV.send(@method, "foo", value).should equal(value)
  end

  it "deletes the environment variable when the value is nil" do
    ENV["foo"] = "bar"
    ENV.send(@method, "foo", nil)
    ENV.key?("foo").should be_false
  end

  it "coerces the key argument with #to_str" do
    k = mock("key")
    k.should_receive(:to_str).and_return("foo")
    ENV.send(@method, k, "bar")
    ENV["foo"].should == "bar"
  end

  it "coerces the value argument with #to_str" do
    v = mock("value")
    v.should_receive(:to_str).and_return("bar")
    ENV.send(@method, "foo", v)
    ENV["foo"].should == "bar"
  end

  it "raises TypeError when the key is not coercible to String" do
    -> { ENV.send(@method, Object.new, "bar") }.should raise_error(TypeError, "no implicit conversion of Object into String")
  end

  it "raises TypeError when the value is not coercible to String" do
    -> { ENV.send(@method, "foo", Object.new) }.should raise_error(TypeError, "no implicit conversion of Object into String")
  end

  it "raises Errno::EINVAL when the key contains the '=' character" do
    -> { ENV.send(@method, "foo=", "bar") }.should raise_error(Errno::EINVAL)
  end

  it "raises Errno::EINVAL when the key is an empty string" do
    -> { ENV.send(@method, "", "bar") }.should raise_error(Errno::EINVAL)
  end

  it "does nothing when the key is not a valid environment variable key and the value is nil" do
    ENV.send(@method, "foo=", nil)
    ENV.key?("foo=").should be_false
  end
end