refactor: unify history and memory in partial_solution (#92)

* refactor: unify history and memory in partial_solution

* refactor: use retain

* refactor: use partition_point

* perf: use more SmallVec

Co-authored-by: Jacob Finkelman <[email protected]>

Author: mpizenberg

src/internal/assignment.rs

@@ -7,9 +7,8 @@ use std::collections::HashSet as Set;
 
 use crate::error::PubGrubError;
 use crate::internal::arena::Arena;
-use crate::internal::assignment::Assignment::{Decision, Derivation};
-use crate::internal::incompatibility::IncompId;
-use crate::internal::incompatibility::{Incompatibility, Relation};
+use crate::internal::incompatibility::{IncompId, Incompatibility, Relation};
+use crate::internal::partial_solution::Assignment::{Decision, Derivation};
 use crate::internal::partial_solution::{DecisionLevel, PartialSolution};
 use crate::internal::small_vec::SmallVec;
 use crate::package::Package;
@@ -175,7 +174,7 @@ impl<P: Package, V: Version> State<P, V> {
                         &self.incompatibility_store[current_incompat_id],
                         &self.incompatibility_store,
                     );
-                match satisfier.clone() {
+                match satisfier {
                     Decision { package, .. } => {
                         self.backtrack(
                             current_incompat_id,

src/internal/core.rs

@@ -54,7 +54,7 @@ enum Kind<P: Package, V: Version> {
 
 /// A Relation describes how a set of terms can be compared to an incompatibility.
 /// Typically, the set of terms comes from the partial solution.
-#[derive(Eq, PartialEq)]
+#[derive(Eq, PartialEq, Debug)]
 pub enum Relation<P: Package> {
     /// We say that a set of terms S satisfies an incompatibility I
     /// if S satisfies every term in I.
@@ -166,11 +166,6 @@ impl<P: Package, V: Version> Incompatibility<P, V> {
         self.package_terms.iter()
     }
 
-    // The number of packages.
-    pub fn len(&self) -> usize {
-        self.package_terms.len()
-    }
-
     // Reporting ###############################################################
 
     /// Retrieve parent causes if of type DerivedFrom.

src/internal/incompatibility.rs

@@ -3,10 +3,8 @@
 //! Non exposed modules.
 
 pub mod arena;
-pub mod assignment;
 pub mod core;
 pub mod incompatibility;
-pub mod memory;
 pub mod partial_solution;
 pub mod small_map;
 pub mod small_vec;