Hadith 4:174
Sahl ibn Yusuf narrated to us, from Shu'bah, who said: I asked al-Hakam about a man who eats the pre-dawn meal (suhur) while he thinks that it is still night. He said: He should complete his fast.
حدثنا سهل بن يوسف عن شعبة قال سألت الحكم عن الرجل يتسحر وهو يرى ان عليه ليلا قال يتم صيامه