WoW:API GetWeaponEnchantInfo

GetWeaponEnchantInfo();

This appears to be used for handling TEMPORARY enchants to weapons - like POISONS. Also appears to be self-only.

Returns

hasMainHandEnchant, mainHandExpiration, mainHandCharges, hasOffHandEnchant, offHandExpiration, offHandCharges

hasMainHandEnchant = 1(true) or nil
mainHandExpiration = time remaining as thousands of seconds
mainHandCharges = charges remaining
hasOffHandEnchant = 1(true) or nil
offHandExpiration = time remaining as thousands of seconds
offHandCharges = charges remaining

Reference the default interface BuffFrame.Lua for its usage.