حَدَّثَنَا الْقَعْنَبِيُّ، عَنْ مَالِكٍ، عَنْ نَافِعٍ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ ‏"‏ إِذَا دُعِيَ أَحَدُكُمْ إِلَى الْوَلِيمَةِ فَلْيَأْتِهَا ‏"‏ ‏.‏

The tradition mentioned above has also been transmitted by Ibn ‘Umar to the same effect through a different chain of narrators. This version has the additional words

If he is not fasting, he should eat, and if he is fasting, he should leave it.