/// A revision specification without any bindings to a repository, useful for serialization or movement over thread boundaries.////// Note that all [object ids][git_hash::ObjectId] should be a committish, but don't have to be./// Unless the field name contains `_exclusive`, the respective objects are included in the set.#[derive(Copy, Clone, Debug, Ord, PartialOrd, Eq, PartialEq, Hash)]#[cfg_attr(feature = "serde1", derive(serde::Serialize, serde::Deserialize))]pub enum Spec {    /// Include commits reachable from this revision, i.e. `a` and its ancestors.    ///    /// The equivalent to [crate::spec::Kind::IncludeReachable], but with data.    Include(git_hash::ObjectId),    /// Exclude commits reachable from this revision, i.e. `a` and its ancestors. Example: `^a`.    ///    /// The equivalent to [crate::spec::Kind::ExcludeReachable], but with data.    Exclude(git_hash::ObjectId),    /// Every commit that is reachable from `from` to `to`, but not any ancestors of `from`. Example: `from..to`.    ///    /// The equivalent to [crate::spec::Kind::RangeBetween], but with data.    Range {        /// The starting point of the range, which is included in the set.        from: git_hash::ObjectId,        /// The end point of the range, which is included in the set.        to: git_hash::ObjectId,    },    /// Every commit reachable through either `theirs` or `ours`, but no commit that is reachable by both. Example: `theirs...ours`.    ///    /// The equivalent to [crate::spec::Kind::ReachableToMergeBase], but with data.    Merge {        /// Their side of the merge, which is included in the set.        theirs: git_hash::ObjectId,        /// Our side of the merge, which is included in the set.        ours: git_hash::ObjectId,    },    /// Include every commit of all parents of `a`, but not `a` itself. Example: `a^@`.    ///    /// The equivalent to [crate::spec::Kind::IncludeReachableFromParents], but with data.    IncludeOnlyParents(        /// Include only the parents of this object, but not the object itself.        git_hash::ObjectId,    ),    /// Exclude every commit of all parents of `a`, but not `a` itself. Example: `a^!`.    ///    /// The equivalent to [crate::spec::Kind::ExcludeReachableFromParents], but with data.    ExcludeParents(        /// Exclude the parents of this object, but not the object itself.        git_hash::ObjectId,    ),}