In a saute pan, warm the oil over medium heat, and sweat the onion until just translucent. Add the carrot and garlic, and stir. After the garlic has browned slightly, sprinkle over the curry powder, and stir. Add the white wine to deglaze the pan. Add the tomatoes and chickpeas to the pan, then stir. Pour in the chicken stock, and bring the mixture to a simmer. Cover the pan with a lid, and cook for 10 minutes. Season the chickpeas with the sugar, and salt, to taste. Remove the pan from the heat and finish the chickpeas by stirring in the cold butter.