01b7686 Turn `Redactable` into a semilattice — heartwood

Radicle Heartwood Protocol & Stack

Turn `Redactable` into a semilattice

Alexis Sellier committed 3 years ago

commit 01b7686659356abd60d71169cc54b05d80b238b6
parent 681a8c9374a5ff39be3f09a2d6475f0638fe3361

4 files changed +63 -10

modified radicle-cob/src/history/entry.rs

@@ -39,6 +39,7 @@ pub struct Entry {

     /// The identifier for this entry
     pub(super) id: EntryId,
     /// The content-address for this entry's author.
     /// TODO: This shouldn't be here?
     pub(super) author: Option<Oid>,
     /// The content-address for the resource this entry lives under.
     pub(super) resource: Oid,

modified radicle-crdt/src/lib.rs

@@ -6,6 +6,7 @@ pub mod lwwmap;

 pub mod lwwreg;
 pub mod lwwset;
 pub mod ord;
 pub mod redactable;
 pub mod thread;
 #[cfg(test)]

added radicle-crdt/src/redactable.rs

@@ -0,0 +1,60 @@

 use crate::Semilattice;
 /// An object that can be either present or removed.
 #[derive(Default, Debug, Clone, Copy, PartialEq, Eq)]
 pub enum Redactable<T> {
     /// When the object is present.
     Present(T),
     /// When the object has been removed.
     #[default]
     Redacted,
 }
 impl<T> From<Option<T>> for Redactable<T> {
     fn from(option: Option<T>) -> Self {
         match option {
             Some(v) => Self::Present(v),
             None => Self::Redacted,
         }
     }
 }
 impl<T: PartialOrd> Redactable<T> {
     pub fn merge(&mut self, other: Self) {
         match (&self, other) {
             (Self::Redacted, _) => {}
             (Self::Present(_), Self::Redacted) => {
                 *self = Self::Redacted;
             }
             (Self::Present(a), Self::Present(b)) => {
                 if &b > a {
                     *self = Self::Present(b);
                 }
             }
         }
     }
 }
 impl<T: PartialOrd> Semilattice for Redactable<T> {
     fn join(mut self, other: Self) -> Self {
         self.merge(other);
         self
     }
 }
 #[cfg(test)]
 mod test {
     use quickcheck_macros::quickcheck;
     use super::*;
     use crate::test;
     #[quickcheck]
     fn prop_invariants(a: Option<u8>, b: Option<u8>, c: Option<u8>) {
         let a = Redactable::from(a);
         let b = Redactable::from(b);
         let c = Redactable::from(c);
         test::assert_laws(&a, &b, &c);
     }
 }

modified radicle-crdt/src/thread.rs

@@ -11,6 +11,7 @@ use radicle::hash;

 use crate::clock::LClock;
 use crate::lwwreg::LWWReg;
 use crate::lwwset::LWWSet;
 use crate::redactable::Redactable;
 /// Identifies a change.
 pub type ChangeId = radicle::hash::Digest;

@@ -63,16 +64,6 @@ pub struct Envelope {

     pub signature: Signature,
 }
 /// An object that can be either present or removed.
 #[derive(Default, Debug, Clone, Copy, PartialEq, Eq)]
 pub enum Redactable<T> {
     /// When the object is present.
     Present(T),
     /// When the object has been removed.
     #[default]
     Redacted,
 }
 /// A comment on a discussion thread.
 #[derive(Default, Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
 pub struct Comment {