public void SetHeaderKeyValuesShouldAppendToExistingHeaders()
{
IHeaderDictionary headers = new HeaderDictionary(
new Dictionary <string, StringValues>()
{
{ "HeaderName", new StringValues("app=id") }
});
HttpHeadersUtilities.SetHeaderKeyValue(headers, "newHeader", "key", "value");
Assert.Equal(2, headers.Count);
Assert.Equal("HeaderName", headers.First().Key);
Assert.Equal("app=id", headers.First().Value);
Assert.Equal("newHeader", headers.Skip(1).First().Key);
Assert.Equal("key=value", headers.Skip(1).First().Value);
}
