feat: use a VersionSet trait instead of Range (pubgrub-rs#108)

* refactor: introduce a trait for sets of versions

* refactor: port report and incompatibility to version set

* refactor: port errors to version set

* refactor: port partial solution to version set

* refactor: move DependencyConstraints to type_aliases

* refactor: port core to version set

* refactor: port solver to version set

* refactor: replace old modules with ones based on version_set

* refactor: update tests to version_set

* feat: add serde bounds to OfflineDependencyProvider

* refactor: update proptest.rs to VersionSet

* docs: fix links

* refactor: allow clippy type_complexity

* Small docs changes

examples/branching_error_reporting.rs

@@ -6,9 +6,11 @@ use pubgrub::report::{DefaultStringReporter, Reporter};
 use pubgrub::solver::{resolve, OfflineDependencyProvider};
 use pubgrub::version::SemanticVersion;
 
+type SemVS = Range<SemanticVersion>;
+
 // https://github.com/dart-lang/pub/blob/master/doc/solver.md#branching-error-reporting
 fn main() {
-    let mut dependency_provider = OfflineDependencyProvider::<&str, SemanticVersion>::new();
+    let mut dependency_provider = OfflineDependencyProvider::<&str, SemVS>::new();
     #[rustfmt::skip]
     // root 1.0.0 depends on foo ^1.0.0
         dependency_provider.add_dependencies(

examples/caching_dependency_provider.rs

@@ -6,16 +6,21 @@ use std::error::Error;
 use pubgrub::package::Package;
 use pubgrub::range::Range;
 use pubgrub::solver::{resolve, Dependencies, DependencyProvider, OfflineDependencyProvider};
-use pubgrub::version::{NumberVersion, Version};
+use pubgrub::version::NumberVersion;
+use pubgrub::version_set::VersionSet;
+
+type NumVS = Range<NumberVersion>;
 
 // An example implementing caching dependency provider that will
 // store queried dependencies in memory and check them before querying more from remote.
-struct CachingDependencyProvider<P: Package, V: Version, DP: DependencyProvider<P, V>> {
+struct CachingDependencyProvider<P: Package, VS: VersionSet, DP: DependencyProvider<P, VS>> {
     remote_dependencies: DP,
-    cached_dependencies: RefCell<OfflineDependencyProvider<P, V>>,
+    cached_dependencies: RefCell<OfflineDependencyProvider<P, VS>>,
 }
 
-impl<P: Package, V: Version, DP: DependencyProvider<P, V>> CachingDependencyProvider<P, V, DP> {
+impl<P: Package, VS: VersionSet, DP: DependencyProvider<P, VS>>
+    CachingDependencyProvider<P, VS, DP>
+{
     pub fn new(remote_dependencies_provider: DP) -> Self {
         CachingDependencyProvider {
             remote_dependencies: remote_dependencies_provider,
@@ -24,22 +29,22 @@ impl<P: Package, V: Version, DP: DependencyProvider<P, V>> CachingDependencyProv
     }
 }
 
-impl<P: Package, V: Version, DP: DependencyProvider<P, V>> DependencyProvider<P, V>
-    for CachingDependencyProvider<P, V, DP>
+impl<P: Package, VS: VersionSet, DP: DependencyProvider<P, VS>> DependencyProvider<P, VS>
+    for CachingDependencyProvider<P, VS, DP>
 {
-    fn choose_package_version<T: std::borrow::Borrow<P>, U: std::borrow::Borrow<Range<V>>>(
+    fn choose_package_version<T: std::borrow::Borrow<P>, U: std::borrow::Borrow<VS>>(
         &self,
         packages: impl Iterator<Item = (T, U)>,
-    ) -> Result<(T, Option<V>), Box<dyn Error>> {
+    ) -> Result<(T, Option<VS::V>), Box<dyn Error>> {
         self.remote_dependencies.choose_package_version(packages)
     }
 
     // Caches dependencies if they were already queried
     fn get_dependencies(
         &self,
         package: &P,
-        version: &V,
-    ) -> Result<Dependencies<P, V>, Box<dyn Error>> {
+        version: &VS::V,
+    ) -> Result<Dependencies<P, VS>, Box<dyn Error>> {
         let mut cache = self.cached_dependencies.borrow_mut();
         match cache.get_dependencies(package, version) {
             Ok(Dependencies::Unknown) => {
@@ -65,7 +70,7 @@ impl<P: Package, V: Version, DP: DependencyProvider<P, V>> DependencyProvider<P,
 
 fn main() {
     // Simulating remote provider locally.
-    let mut remote_dependencies_provider = OfflineDependencyProvider::<&str, NumberVersion>::new();
+    let mut remote_dependencies_provider = OfflineDependencyProvider::<&str, NumVS>::new();
 
     // Add dependencies as needed. Here only root package is added.
     remote_dependencies_provider.add_dependencies("root", 1, Vec::new());

examples/doc_interface.rs

@@ -4,13 +4,15 @@ use pubgrub::range::Range;
 use pubgrub::solver::{resolve, OfflineDependencyProvider};
 use pubgrub::version::NumberVersion;
 
+type NumVS = Range<NumberVersion>;
+
 // `root` depends on `menu` and `icons`
 // `menu` depends on `dropdown`
 // `dropdown` depends on `icons`
 // `icons` has no dependency
 #[rustfmt::skip]
 fn main() {
-    let mut dependency_provider = OfflineDependencyProvider::<&str, NumberVersion>::new();
+    let mut dependency_provider = OfflineDependencyProvider::<&str, NumVS>::new();
     dependency_provider.add_dependencies(
         "root", 1, [("menu", Range::any()), ("icons", Range::any())],
     );

examples/doc_interface_error.rs

@@ -6,6 +6,8 @@ use pubgrub::report::{DefaultStringReporter, Reporter};
 use pubgrub::solver::{resolve, OfflineDependencyProvider};
 use pubgrub::version::SemanticVersion;
 
+type SemVS = Range<SemanticVersion>;
+
 // `root` depends on `menu`, `icons 1.0.0` and `intl 5.0.0`
 // `menu 1.0.0` depends on `dropdown < 2.0.0`
 // `menu >= 1.1.0` depends on `dropdown >= 2.0.0`
@@ -15,7 +17,7 @@ use pubgrub::version::SemanticVersion;
 // `intl` has no dependency
 #[rustfmt::skip]
 fn main() {
-    let mut dependency_provider = OfflineDependencyProvider::<&str, SemanticVersion>::new();
+    let mut dependency_provider = OfflineDependencyProvider::<&str, SemVS>::new();
     // Direct dependencies: menu and icons.
     dependency_provider.add_dependencies("root", (1, 0, 0), [
         ("menu", Range::any()),

examples/doc_interface_semantic.rs

@@ -6,6 +6,8 @@ use pubgrub::report::{DefaultStringReporter, Reporter};
 use pubgrub::solver::{resolve, OfflineDependencyProvider};
 use pubgrub::version::SemanticVersion;
 
+type SemVS = Range<SemanticVersion>;
+
 // `root` depends on `menu` and `icons 1.0.0`
 // `menu 1.0.0` depends on `dropdown < 2.0.0`
 // `menu >= 1.1.0` depends on `dropdown >= 2.0.0`
@@ -14,7 +16,7 @@ use pubgrub::version::SemanticVersion;
 // `icons` has no dependency
 #[rustfmt::skip]
 fn main() {
-    let mut dependency_provider = OfflineDependencyProvider::<&str, SemanticVersion>::new();
+    let mut dependency_provider = OfflineDependencyProvider::<&str, SemVS>::new();
     // Direct dependencies: menu and icons.
     dependency_provider.add_dependencies("root", (1, 0, 0), [
         ("menu", Range::any()),

examples/linear_error_reporting.rs

@@ -6,9 +6,11 @@ use pubgrub::report::{DefaultStringReporter, Reporter};
 use pubgrub::solver::{resolve, OfflineDependencyProvider};
 use pubgrub::version::SemanticVersion;
 
+type SemVS = Range<SemanticVersion>;
+
 // https://github.com/dart-lang/pub/blob/master/doc/solver.md#linear-error-reporting
 fn main() {
-    let mut dependency_provider = OfflineDependencyProvider::<&str, SemanticVersion>::new();
+    let mut dependency_provider = OfflineDependencyProvider::<&str, SemVS>::new();
     #[rustfmt::skip]
     // root 1.0.0 depends on foo ^1.0.0 and baz ^1.0.0
         dependency_provider.add_dependencies(

src/error.rs

@@ -6,14 +6,14 @@ use thiserror::Error;
 
 use crate::package::Package;
 use crate::report::DerivationTree;
-use crate::version::Version;
+use crate::version_set::VersionSet;
 
 /// Errors that may occur while solving dependencies.
 #[derive(Error, Debug)]
-pub enum PubGrubError<P: Package, V: Version> {
+pub enum PubGrubError<P: Package, VS: VersionSet> {
     /// There is no solution for this set of dependencies.
     #[error("No solution")]
-    NoSolution(DerivationTree<P, V>),
+    NoSolution(DerivationTree<P, VS>),
 
     /// Error arising when the implementer of
     /// [DependencyProvider](crate::solver::DependencyProvider)
@@ -24,7 +24,7 @@ pub enum PubGrubError<P: Package, V: Version> {
         /// Package whose dependencies we want.
         package: P,
         /// Version of the package for which we want the dependencies.
-        version: V,
+        version: VS::V,
         /// Error raised by the implementer of
         /// [DependencyProvider](crate::solver::DependencyProvider).
         source: Box<dyn std::error::Error>,
@@ -40,7 +40,7 @@ pub enum PubGrubError<P: Package, V: Version> {
         /// Package whose dependencies we want.
         package: P,
         /// Version of the package for which we want the dependencies.
-        version: V,
+        version: VS::V,
         /// The dependent package that requires us to pick from the empty set.
         dependent: P,
     },
@@ -55,7 +55,7 @@ pub enum PubGrubError<P: Package, V: Version> {
         /// Package whose dependencies we want.
         package: P,
         /// Version of the package for which we want the dependencies.
-        version: V,
+        version: VS::V,
     },
 
     /// Error arising when the implementer of

src/internal/core.rs

@@ -15,38 +15,37 @@ use crate::internal::partial_solution::{DecisionLevel, PartialSolution};
 use crate::internal::small_vec::SmallVec;
 use crate::package::Package;
 use crate::report::DerivationTree;
-use crate::solver::DependencyConstraints;
-use crate::type_aliases::Map;
-use crate::version::Version;
+use crate::type_aliases::{DependencyConstraints, Map};
+use crate::version_set::VersionSet;
 
 /// Current state of the PubGrub algorithm.
 #[derive(Clone)]
-pub struct State<P: Package, V: Version> {
+pub struct State<P: Package, VS: VersionSet> {
     root_package: P,
-    root_version: V,
+    root_version: VS::V,
 
-    incompatibilities: Map<P, Vec<IncompId<P, V>>>,
+    incompatibilities: Map<P, Vec<IncompId<P, VS>>>,
 
     /// Store the ids of incompatibilities that are already contradicted
     /// and will stay that way until the next conflict and backtrack is operated.
-    contradicted_incompatibilities: rustc_hash::FxHashSet<IncompId<P, V>>,
+    contradicted_incompatibilities: rustc_hash::FxHashSet<IncompId<P, VS>>,
 
     /// Partial solution.
     /// TODO: remove pub.
-    pub partial_solution: PartialSolution<P, V>,
+    pub partial_solution: PartialSolution<P, VS>,
 
     /// The store is the reference storage for all incompatibilities.
-    pub incompatibility_store: Arena<Incompatibility<P, V>>,
+    pub incompatibility_store: Arena<Incompatibility<P, VS>>,
 
     /// This is a stack of work to be done in `unit_propagation`.
     /// It can definitely be a local variable to that method, but
     /// this way we can reuse the same allocation for better performance.
     unit_propagation_buffer: SmallVec<P>,
 }
 
-impl<P: Package, V: Version> State<P, V> {
+impl<P: Package, VS: VersionSet> State<P, VS> {
     /// Initialization of PubGrub state.
-    pub fn init(root_package: P, root_version: V) -> Self {
+    pub fn init(root_package: P, root_version: VS::V) -> Self {
         let mut incompatibility_store = Arena::new();
         let not_root_id = incompatibility_store.alloc(Incompatibility::not_root(
             root_package.clone(),
@@ -66,7 +65,7 @@ impl<P: Package, V: Version> State<P, V> {
     }
 
     /// Add an incompatibility to the state.
-    pub fn add_incompatibility(&mut self, incompat: Incompatibility<P, V>) {
+    pub fn add_incompatibility(&mut self, incompat: Incompatibility<P, VS>) {
         let id = self.incompatibility_store.alloc(incompat);
         self.merge_incompatibility(id);
     }
@@ -75,9 +74,9 @@ impl<P: Package, V: Version> State<P, V> {
     pub fn add_incompatibility_from_dependencies(
         &mut self,
         package: P,
-        version: V,
-        deps: &DependencyConstraints<P, V>,
-    ) -> std::ops::Range<IncompId<P, V>> {
+        version: VS::V,
+        deps: &DependencyConstraints<P, VS>,
+    ) -> std::ops::Range<IncompId<P, VS>> {
         // Create incompatibilities and allocate them in the store.
         let new_incompats_id_range = self
             .incompatibility_store
@@ -92,13 +91,13 @@ impl<P: Package, V: Version> State<P, V> {
     }
 
     /// Check if an incompatibility is terminal.
-    pub fn is_terminal(&self, incompatibility: &Incompatibility<P, V>) -> bool {
+    pub fn is_terminal(&self, incompatibility: &Incompatibility<P, VS>) -> bool {
         incompatibility.is_terminal(&self.root_package, &self.root_version)
     }
 
     /// Unit propagation is the core mechanism of the solving algorithm.
     /// CF <https://github.com/dart-lang/pub/blob/master/doc/solver.md#unit-propagation>
-    pub fn unit_propagation(&mut self, package: P) -> Result<(), PubGrubError<P, V>> {
+    pub fn unit_propagation(&mut self, package: P) -> Result<(), PubGrubError<P, VS>> {
         self.unit_propagation_buffer.clear();
         self.unit_propagation_buffer.push(package);
         while let Some(current_package) = self.unit_propagation_buffer.pop() {
@@ -162,8 +161,8 @@ impl<P: Package, V: Version> State<P, V> {
     /// CF <https://github.com/dart-lang/pub/blob/master/doc/solver.md#unit-propagation>
     fn conflict_resolution(
         &mut self,
-        incompatibility: IncompId<P, V>,
-    ) -> Result<(P, IncompId<P, V>), PubGrubError<P, V>> {
+        incompatibility: IncompId<P, VS>,
+    ) -> Result<(P, IncompId<P, VS>), PubGrubError<P, VS>> {
         let mut current_incompat_id = incompatibility;
         let mut current_incompat_changed = false;
         loop {
@@ -209,7 +208,7 @@ impl<P: Package, V: Version> State<P, V> {
     /// Backtracking.
     fn backtrack(
         &mut self,
-        incompat: IncompId<P, V>,
+        incompat: IncompId<P, VS>,
         incompat_changed: bool,
         decision_level: DecisionLevel,
     ) {
@@ -240,7 +239,7 @@ impl<P: Package, V: Version> State<P, V> {
     /// Here we do the simple stupid thing of just growing the Vec.
     /// It may not be trivial since those incompatibilities
     /// may already have derived others.
-    fn merge_incompatibility(&mut self, id: IncompId<P, V>) {
+    fn merge_incompatibility(&mut self, id: IncompId<P, VS>) {
         for (pkg, _term) in self.incompatibility_store[id].iter() {
             self.incompatibilities
                 .entry(pkg.clone())
@@ -251,12 +250,12 @@ impl<P: Package, V: Version> State<P, V> {
 
     // Error reporting #########################################################
 
-    fn build_derivation_tree(&self, incompat: IncompId<P, V>) -> DerivationTree<P, V> {
+    fn build_derivation_tree(&self, incompat: IncompId<P, VS>) -> DerivationTree<P, VS> {
         let shared_ids = self.find_shared_ids(incompat);
         Incompatibility::build_derivation_tree(incompat, &shared_ids, &self.incompatibility_store)
     }
 
-    fn find_shared_ids(&self, incompat: IncompId<P, V>) -> Set<IncompId<P, V>> {
+    fn find_shared_ids(&self, incompat: IncompId<P, VS>) -> Set<IncompId<P, VS>> {
         let mut all_ids = Set::new();
         let mut shared_ids = Set::new();
         let mut stack = vec![incompat];