Add experimental u64 version bitset

src/experimental/helpers.rs

@@ -0,0 +1,355 @@
+//! Helpers structs.
+
+use std::fmt::{self, Display};
+use std::iter::repeat_n;
+use std::num::NonZeroU64;
+use std::rc::Rc;
+
+use crate::experimental::{VersionIndex, VersionSet};
+
+/// Package allowing more than 63 versions.
+#[derive(Debug, Clone, Eq, PartialEq, Hash)]
+pub struct Pkg<P> {
+    pkg: P,
+    quotient: u64,
+    count: u64,
+}
+
+impl<P> Pkg<P> {
+    /// Get the inner package.
+    pub fn pkg(&self) -> &P {
+        &self.pkg
+    }
+}
+
+impl<P: Display> Display for Pkg<P> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{} (q={})", self.pkg, self.quotient)
+    }
+}
+
+/// Virtual package ensuring package unicity.
+#[derive(Debug, Clone, Eq, PartialEq, Hash)]
+pub struct VirtualPkg<P> {
+    pkg: P,
+    quotient: u64,
+    count: u64,
+}
+
+impl<P> VirtualPkg<P> {
+    /// Get the inner package.
+    pub fn pkg(&self) -> &P {
+        &self.pkg
+    }
+}
+
+impl<P: Display> Display for VirtualPkg<P> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(
+            f,
+            "VirtualPkg({}, q={}, c={})",
+            self.pkg, self.quotient, self.count
+        )
+    }
+}
+
+/// Virtual package dependency allowing more than 63 versions.
+#[derive(Debug, Clone, Eq, PartialEq, Hash)]
+pub struct VirtualDep<P> {
+    pkg: P,
+    version_indices: Rc<[VersionSet]>,
+    offset: u64,
+    quotient: u64,
+}
+
+impl<P> VirtualDep<P> {
+    /// Get the inner package.
+    pub fn pkg(&self) -> &P {
+        &self.pkg
+    }
+}
+
+impl<P: Display> Display for VirtualDep<P> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let vc = self
+            .version_indices
+            .iter()
+            .map(|vs| vs.count())
+            .sum::<usize>();
+
+        write!(
+            f,
+            "VirtualDep({}, vc={vc}, o={}, q={})",
+            self.pkg, self.offset, self.quotient
+        )
+    }
+}
+
+/// Package wrapper used to allow more than 63 versions per package.
+#[derive(Debug, Clone, Eq, PartialEq, Hash)]
+pub enum PackageVersionWrapper<P: Clone + Display> {
+    /// Package allowing more than 63 versions
+    Pkg(Pkg<P>),
+    /// Virtual package ensuring package unicity
+    VirtualPkg(VirtualPkg<P>),
+    /// Virtual package dependency allowing more than 63 versions
+    VirtualDep(VirtualDep<P>),
+}
+
+impl<P: Clone + Display> Display for PackageVersionWrapper<P> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            Self::Pkg(p) => p.fmt(f),
+            Self::VirtualPkg(vp) => vp.fmt(f),
+            Self::VirtualDep(vd) => vd.fmt(f),
+        }
+    }
+}
+
+impl<P: Clone + Display> PackageVersionWrapper<P> {
+    /// Create a new package.
+    pub fn new_pkg(
+        pkg: P,
+        true_version_index: u64,
+        version_count: NonZeroU64,
+    ) -> (Self, VersionIndex) {
+        (
+            Self::Pkg(Pkg {
+                pkg,
+                quotient: true_version_index / VersionIndex::MAX,
+                count: (version_count.get() - 1) / VersionIndex::MAX,
+            }),
+            VersionIndex::new((true_version_index % VersionIndex::MAX) as u8).unwrap(),
+        )
+    }
+
+    /// Create a new package dependency with no versions.
+    pub fn new_empty_dep(pkg: P) -> (Self, VersionSet) {
+        (
+            Self::Pkg(Pkg {
+                pkg,
+                quotient: 0,
+                count: 0,
+            }),
+            VersionSet::empty(),
+        )
+    }
+
+    /// Create a new package dependency at the specified version.
+    pub fn new_singleton_dep(
+        pkg: P,
+        true_version_index: u64,
+        version_count: u64,
+    ) -> (Self, VersionSet) {
+        match NonZeroU64::new(version_count) {
+            Some(version_count) => {
+                assert!(true_version_index < version_count.get());
+                let (this, v) = Self::new_pkg(pkg, true_version_index, version_count);
+                (this, VersionSet::singleton(v))
+            }
+            None => Self::new_empty_dep(pkg),
+        }
+    }
+
+    /// Create a new package dependency at the specified versions.
+    pub fn new_dep(
+        pkg: P,
+        true_version_indices: impl IntoIterator<Item = u64>,
+        version_count: u64,
+    ) -> (Self, VersionSet) {
+        let Some(nz_version_count) = NonZeroU64::new(version_count) else {
+            return Self::new_empty_dep(pkg);
+        };
+        if version_count <= VersionIndex::MAX {
+            let mut set = VersionSet::empty();
+            for true_version_index in true_version_indices {
+                assert!(true_version_index < version_count);
+                let v = VersionIndex::new(true_version_index as u8).unwrap();
+                set = set.union(VersionSet::singleton(v));
+            }
+            return (
+                Self::Pkg(Pkg {
+                    pkg,
+                    quotient: 0,
+                    count: (version_count - 1) / VersionIndex::MAX,
+                }),
+                set,
+            );
+        }
+
+        let mut true_version_indices = true_version_indices.into_iter();
+
+        let Some(first) = true_version_indices.next() else {
+            return Self::new_empty_dep(pkg);
+        };
+        assert!(first < version_count);
+
+        let Some(second) = true_version_indices.next() else {
+            let (d, vs) = Self::new_pkg(pkg, first, nz_version_count);
+            return (d, VersionSet::singleton(vs));
+        };
+        assert!(second < version_count);
+
+        let mut version_indices = Rc::from_iter(repeat_n(
+            VersionSet::empty(),
+            (1 + (version_count - 1) / VersionIndex::MAX) as usize,
+        ));
+        let versions_slice = Rc::make_mut(&mut version_indices);
+
+        for true_version_index in [first, second].into_iter().chain(true_version_indices) {
+            assert!(true_version_index < version_count);
+            let index = (true_version_index / VersionIndex::MAX) as usize;
+            let v = VersionIndex::new((true_version_index % VersionIndex::MAX) as u8).unwrap();
+            let set = versions_slice.get_mut(index).unwrap();
+            *set = set.union(VersionSet::singleton(v));
+        }
+
+        let offset = 0;
+        let quotient = VersionIndex::MAX.pow(version_count.ilog(VersionIndex::MAX) - 1);
+        let version_set = Self::dep_version_set(&version_indices, offset, quotient);
+
+        let this = Self::VirtualDep(VirtualDep {
+            pkg,
+            version_indices,
+            offset,
+            quotient,
+        });
+
+        (this, version_set)
+    }
+
+    /// Clone and replace the package of this wrapper.
+    pub fn replace_pkg<T: Clone + Display>(&self, new_pkg: T) -> PackageVersionWrapper<T> {
+        match *self {
+            Self::Pkg(Pkg {
+                pkg: _,
+                quotient,
+                count,
+            }) => PackageVersionWrapper::Pkg(Pkg {
+                pkg: new_pkg,
+                quotient,
+                count,
+            }),
+            Self::VirtualPkg(VirtualPkg {
+                pkg: _,
+                quotient,
+                count,
+            }) => PackageVersionWrapper::VirtualPkg(VirtualPkg {
+                pkg: new_pkg,
+                quotient,
+                count,
+            }),
+            Self::VirtualDep(VirtualDep {
+                pkg: _,
+                ref version_indices,
+                offset,
+                quotient,
+            }) => PackageVersionWrapper::VirtualDep(VirtualDep {
+                pkg: new_pkg,
+                version_indices: version_indices.clone(),
+                offset,
+                quotient,
+            }),
+        }
+    }
+
+    /// Get the inner package if existing.
+    pub fn inner_pkg(&self) -> Option<&P> {
+        match self {
+            Self::Pkg(Pkg { pkg, .. }) => Some(pkg),
+            _ => None,
+        }
+    }
+
+    /// Get the inner package if existing.
+    pub fn inner(&self, version_index: VersionIndex) -> Option<(&P, u64)> {
+        match self {
+            Self::Pkg(Pkg { pkg, quotient, .. }) => Some((
+                pkg,
+                quotient * VersionIndex::MAX + version_index.get() as u64,
+            )),
+            _ => None,
+        }
+    }
+
+    /// Get the inner package if existing.
+    pub fn into_inner(self, version_index: VersionIndex) -> Option<(P, u64)> {
+        match self {
+            Self::Pkg(Pkg { pkg, quotient, .. }) => Some((
+                pkg,
+                quotient * VersionIndex::MAX + version_index.get() as u64,
+            )),
+            _ => None,
+        }
+    }
+
+    /// Get the wrapper virtual dependency if existing.
+    pub fn dependency(&self, version_index: VersionIndex) -> Option<(Self, VersionSet)> {
+        match *self {
+            Self::Pkg(Pkg {
+                ref pkg,
+                quotient,
+                count,
+            })
+            | Self::VirtualPkg(VirtualPkg {
+                ref pkg,
+                quotient,
+                count,
+            }) => {
+                if count == 0 {
+                    None
+                } else {
+                    Some((
+                        Self::VirtualPkg(VirtualPkg {
+                            pkg: pkg.clone(),
+                            quotient: quotient / VersionIndex::MAX,
+                            count: count / VersionIndex::MAX,
+                        }),
+                        VersionSet::singleton(
+                            VersionIndex::new((quotient % VersionIndex::MAX) as u8).unwrap(),
+                        ),
+                    ))
+                }
+            }
+            Self::VirtualDep(VirtualDep {
+                ref pkg,
+                ref version_indices,
+                offset,
+                quotient,
+            }) => {
+                let offset = offset + version_index.get() as u64 * quotient;
+                if quotient == 1 {
+                    return Some((
+                        Self::Pkg(Pkg {
+                            pkg: pkg.clone(),
+                            quotient: offset,
+                            count: (version_indices.len() - 1) as u64,
+                        }),
+                        version_indices[offset as usize],
+                    ));
+                }
+                let quotient = quotient / VersionIndex::MAX;
+                let version_set = Self::dep_version_set(version_indices, offset, quotient);
+
+                let this = Self::VirtualDep(VirtualDep {
+                    pkg: pkg.clone(),
+                    version_indices: version_indices.clone(),
+                    offset,
+                    quotient,
+                });
+
+                Some((this, version_set))
+            }
+        }
+    }
+
+    fn dep_version_set(sets: &[VersionSet], offset: u64, quotient: u64) -> VersionSet {
+        sets[offset as usize..]
+            .chunks(quotient as usize)
+            .take(VersionIndex::MAX as usize)
+            .enumerate()
+            .filter(|&(_, sets)| sets.iter().any(|&vs| vs != VersionSet::empty()))
+            .map(|(i, _)| VersionSet::singleton(VersionIndex::new(i as u8).unwrap()))
+            .fold(VersionSet::empty(), |acc, vs| acc.union(vs))
+    }
+}

src/experimental/mod.rs

@@ -0,0 +1,6 @@
+pub mod helpers;
+mod term;
+mod version;
+
+pub use term::Term;
+pub use version::{VersionIndex, VersionSet};