Imam Abu Haneefah prayed Fajer salah with the same wudu of Isha for 40 years. And Imam Abu Hanifah refrained to do Wudu in the Masjid because Allah had blessed him with a miracle. He was able to see the sins coming off a person doing wudhu- so to prevent him having bad thoughts of people- he always did wudu elsewhere.
Note: Imam Abu Hanifa rahimahullah was one of the well known scholars of Islam, but there is no need for fabricated stories such as the ones above in order to prove so. Additionally, it is not from the sunnah to pray all night long on every night, as the Prophet (peace & blessings upon him) used to pray part of the night and sleep part of it.
Al-Bukhari (5063) and Muslim (1401) narrated that Anas ibn Malik said: Three people came to the houses of the wives of the Prophet (peace and blessings of Allah be upon him) asking about the worship of the Prophet (peace and blessings of Allah be upon him). When they were told, it was as if they regarded it as too little. They said: Who are we in comparison to the Prophet (peace and blessings of Allah be upon him)? Allah has forgiven his past and future sins. One of them said: As for me, I will pray all night forever. Another said: I shall fast all my life and never break my fast. Another said: I shall keep away from women and never get married. The Messenger of Allah (peace and blessings of Allah be upon him) came and said: “Are you the ones who said such and such? By Allah, I am the one who fears Allah the most among you and I am the most pious, but I fast and I break my fast, I pray and I sleep, and I marry women. Whoever turns away from my Sunnah is not of me.” Narrated by al-Bukhaari (5063) and Muslim (1401).