function dedupe(unique, item) {
            if (item.file != null) {
                const toDeleteIndex = unique.findIndex(
                    element =>
                        element.file &&
                        element.file.resolved === (item.file && item.file.resolved)
                );

                if (toDeleteIndex >= 0) {
                    unique.splice(toDeleteIndex, 1);
                }
            }

            return [...unique, item];
        }
@param {import("@babel/core").ConfigItem[]} unique
@param {import("@babel/core").ConfigItem} item