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store this in constraint, not node

This commit is contained in:
Douglas Creager 2025-12-15 16:36:53 -05:00
parent c790aa7474
commit 0b6bd9a735
1 changed files with 147 additions and 210 deletions
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357
crates/ty_python_semantic/src/types/constraints.rs
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@ -496,9 +496,10 @@ impl IntersectionResult<'_> {
/// lower and upper bound.
#[salsa::interned(debug, heap_size=ruff_memory_usage::heap_size)]
pub(crate) struct ConstrainedTypeVar<'db> {
typevar: BoundTypeVarInstance<'db>,
lower: Type<'db>,
upper: Type<'db>,
pub(crate) typevar: BoundTypeVarInstance<'db>,
pub(crate) lower: Type<'db>,
pub(crate) upper: Type<'db>,
pub(crate) explicit: ExplicitConstraint,
}
// The Salsa heap is tracked separately.
@ -586,8 +587,7 @@ impl<'db> ConstrainedTypeVar<'db> {
{
return Node::new_constraint(
db,
ConstrainedTypeVar::new(db, typevar, Type::Never, Type::object()),
explicit,
ConstrainedTypeVar::new(db, typevar, Type::Never, Type::object(), explicit),
1,
)
.negate(db);
@ -639,8 +639,8 @@ impl<'db> ConstrainedTypeVar<'db> {
typevar,
Type::TypeVar(bound),
Type::TypeVar(bound),
explicit,
),
explicit,
1,
)
}
@ -651,14 +651,24 @@ impl<'db> ConstrainedTypeVar<'db> {
{
let lower = Node::new_constraint(
db,
ConstrainedTypeVar::new(db, lower, Type::Never, Type::TypeVar(typevar)),
explicit,
ConstrainedTypeVar::new(
db,
lower,
Type::Never,
Type::TypeVar(typevar),
explicit,
),
1,
);
let upper = Node::new_constraint(
db,
ConstrainedTypeVar::new(db, upper, Type::TypeVar(typevar), Type::object()),
explicit,
ConstrainedTypeVar::new(
db,
upper,
Type::TypeVar(typevar),
Type::object(),
explicit,
),
1,
);
lower.and(db, upper)
@ -668,8 +678,13 @@ impl<'db> ConstrainedTypeVar<'db> {
(Type::TypeVar(lower), _) if typevar.can_be_bound_for(db, lower) => {
let lower = Node::new_constraint(
db,
ConstrainedTypeVar::new(db, lower, Type::Never, Type::TypeVar(typevar)),
explicit,
ConstrainedTypeVar::new(
db,
lower,
Type::Never,
Type::TypeVar(typevar),
explicit,
),
1,
);
let upper = if upper.is_object() {
@ -689,8 +704,13 @@ impl<'db> ConstrainedTypeVar<'db> {
};
let upper = Node::new_constraint(
db,
ConstrainedTypeVar::new(db, upper, Type::TypeVar(typevar), Type::object()),
explicit,
ConstrainedTypeVar::new(
db,
upper,
Type::TypeVar(typevar),
Type::object(),
explicit,
),
1,
);
lower.and(db, upper)
@ -698,8 +718,7 @@ impl<'db> ConstrainedTypeVar<'db> {
_ => Node::new_constraint(
db,
ConstrainedTypeVar::new(db, typevar, lower, upper),
explicit,
ConstrainedTypeVar::new(db, typevar, lower, upper, explicit),
1,
),
}
@ -719,6 +738,7 @@ impl<'db> ConstrainedTypeVar<'db> {
self.typevar(db),
self.lower(db).normalized(db),
self.upper(db).normalized(db),
self.explicit(db),
)
}
@ -735,7 +755,12 @@ impl<'db> ConstrainedTypeVar<'db> {
/// simplifications that we perform that operate on constraints with the same typevar, and this
/// ensures that we can find all candidate simplifications more easily.
fn ordering(self, db: &'db dyn Db) -> impl Ord {
(self.typevar(db).identity(db), self.as_id())
(
self.typevar(db).binding_context(db),
self.typevar(db).identity(db),
self.explicit(db),
self.as_id(),
)
}
/// Returns whether this constraint implies another — i.e., whether every type that
@ -767,7 +792,13 @@ impl<'db> ConstrainedTypeVar<'db> {
return IntersectionResult::CannotSimplify;
}
IntersectionResult::Simplified(Self::new(db, self.typevar(db), lower, upper))
IntersectionResult::Simplified(Self::new(
db,
self.typevar(db),
lower,
upper,
self.explicit(db) & other.explicit(db),
))
}
fn display(self, db: &'db dyn Db) -> impl Display {
@ -890,7 +921,6 @@ impl<'db> Node<'db> {
constraint: ConstrainedTypeVar<'db>,
if_true: Node<'db>,
if_false: Node<'db>,
explicit: ExplicitConstraint,
source_order: usize,
) -> Self {
debug_assert!((if_true.root_constraint(db)).is_none_or(|root_constraint| {
@ -912,7 +942,6 @@ impl<'db> Node<'db> {
constraint,
if_true,
if_false,
explicit,
source_order,
max_source_order,
))
@ -923,7 +952,6 @@ impl<'db> Node<'db> {
fn new_constraint(
db: &'db dyn Db,
constraint: ConstrainedTypeVar<'db>,
explicit: ExplicitConstraint,
source_order: usize,
) -> Self {
Self::Interior(InteriorNode::new(
@ -931,7 +959,6 @@ impl<'db> Node<'db> {
constraint,
Node::AlwaysTrue,
Node::AlwaysFalse,
explicit,
source_order,
source_order,
))
@ -943,7 +970,6 @@ impl<'db> Node<'db> {
fn new_satisfied_constraint(
db: &'db dyn Db,
constraint: ConstraintAssignment<'db>,
explicit: ExplicitConstraint,
source_order: usize,
) -> Self {
match constraint {
@ -952,7 +978,6 @@ impl<'db> Node<'db> {
constraint,
Node::AlwaysTrue,
Node::AlwaysFalse,
explicit,
source_order,
source_order,
)),
@ -961,7 +986,6 @@ impl<'db> Node<'db> {
constraint,
Node::AlwaysFalse,
Node::AlwaysTrue,
explicit,
source_order,
source_order,
)),
@ -997,7 +1021,6 @@ impl<'db> Node<'db> {
interior.constraint(db),
interior.if_true(db).with_adjusted_source_order(db, delta),
interior.if_false(db).with_adjusted_source_order(db, delta),
interior.explicit(db),
interior.source_order(db) + delta,
),
}
@ -1030,39 +1053,24 @@ impl<'db> Node<'db> {
// from it) causes the if_true edge to become impossible. We want to ignore
// impossible paths, and so we treat them as passing the "always satisfied" check.
let constraint = interior.constraint(db);
let explicit = interior.explicit(db);
let source_order = interior.source_order(db);
let true_always_satisfied = path
.walk_edge(
db,
map,
constraint.when_true(),
explicit,
source_order,
|path, _| {
interior
.if_true(db)
.is_always_satisfied_inner(db, map, path)
},
)
.walk_edge(db, map, constraint.when_true(), source_order, |path, _| {
interior
.if_true(db)
.is_always_satisfied_inner(db, map, path)
})
.unwrap_or(true);
if !true_always_satisfied {
return false;
}
// Ditto for the if_false branch
path.walk_edge(
db,
map,
constraint.when_false(),
explicit,
source_order,
|path, _| {
interior
.if_false(db)
.is_always_satisfied_inner(db, map, path)
},
)
path.walk_edge(db, map, constraint.when_false(), source_order, |path, _| {
interior
.if_false(db)
.is_always_satisfied_inner(db, map, path)
})
.unwrap_or(true)
}
}
@ -1095,35 +1103,22 @@ impl<'db> Node<'db> {
// from it) causes the if_true edge to become impossible. We want to ignore
// impossible paths, and so we treat them as passing the "never satisfied" check.
let constraint = interior.constraint(db);
let explicit = interior.explicit(db);
let source_order = interior.source_order(db);
let true_never_satisfied = path
.walk_edge(
db,
map,
constraint.when_true(),
explicit,
source_order,
|path, _| interior.if_true(db).is_never_satisfied_inner(db, map, path),
)
.walk_edge(db, map, constraint.when_true(), source_order, |path, _| {
interior.if_true(db).is_never_satisfied_inner(db, map, path)
})
.unwrap_or(true);
if !true_never_satisfied {
return false;
}
// Ditto for the if_false branch
path.walk_edge(
db,
map,
constraint.when_false(),
explicit,
source_order,
|path, _| {
interior
.if_false(db)
.is_never_satisfied_inner(db, map, path)
},
)
path.walk_edge(db, map, constraint.when_false(), source_order, |path, _| {
interior
.if_false(db)
.is_never_satisfied_inner(db, map, path)
})
.unwrap_or(true)
}
}
@ -1166,7 +1161,6 @@ impl<'db> Node<'db> {
other_interior.constraint(db),
Node::AlwaysTrue,
Node::AlwaysTrue,
other_interior.explicit(db),
other_interior.source_order(db) + other_offset,
),
(Node::Interior(self_interior), Node::AlwaysTrue) => Node::new(
@ -1174,7 +1168,6 @@ impl<'db> Node<'db> {
self_interior.constraint(db),
Node::AlwaysTrue,
Node::AlwaysTrue,
self_interior.explicit(db),
self_interior.source_order(db),
),
(Node::AlwaysFalse, _) => other.with_adjusted_source_order(db, other_offset),
@ -1208,7 +1201,6 @@ impl<'db> Node<'db> {
other_interior.constraint(db),
Node::AlwaysFalse,
Node::AlwaysFalse,
other_interior.explicit(db),
other_interior.source_order(db) + other_offset,
),
(Node::Interior(self_interior), Node::AlwaysFalse) => Node::new(
@ -1216,7 +1208,6 @@ impl<'db> Node<'db> {
self_interior.constraint(db),
Node::AlwaysFalse,
Node::AlwaysFalse,
self_interior.explicit(db),
self_interior.source_order(db),
),
(Node::AlwaysTrue, _) => other.with_adjusted_source_order(db, other_offset),
@ -1261,7 +1252,6 @@ impl<'db> Node<'db> {
interior.constraint(db),
self.iff_inner(db, interior.if_true(db), other_offset),
self.iff_inner(db, interior.if_false(db), other_offset),
interior.explicit(db),
interior.source_order(db) + other_offset,
),
(Node::Interior(interior), Node::AlwaysTrue | Node::AlwaysFalse) => Node::new(
@ -1269,7 +1259,6 @@ impl<'db> Node<'db> {
interior.constraint(db),
interior.if_true(db).iff_inner(db, other, other_offset),
interior.if_false(db).iff_inner(db, other, other_offset),
interior.explicit(db),
interior.source_order(db),
),
(Node::Interior(a), Node::Interior(b)) => a.iff(db, b, other_offset),
@ -1595,18 +1584,8 @@ impl<'db> Node<'db> {
// false
//
// (Note that the `else` branch shouldn't be reachable, but we have to provide something!)
let left_node = Node::new_satisfied_constraint(
db,
left,
ExplicitConstraint::Implicit,
left_source_order,
);
let right_node = Node::new_satisfied_constraint(
db,
right,
ExplicitConstraint::Implicit,
right_source_order,
);
let left_node = Node::new_satisfied_constraint(db, left, left_source_order);
let right_node = Node::new_satisfied_constraint(db, right, right_source_order);
let right_result = right_node.ite(db, Node::AlwaysFalse, when_left_but_not_right);
let left_result = left_node.ite(db, right_result, when_not_left);
let result = replacement.ite(db, when_left_and_right, left_result);
@ -1671,18 +1650,8 @@ impl<'db> Node<'db> {
// Lastly, verify that the result is consistent with the input. (It must produce the same
// results when `left ∨ right`.) If it doesn't, the substitution isn't valid, and we should
// return the original BDD unmodified.
let left_node = Node::new_satisfied_constraint(
db,
left,
ExplicitConstraint::Implicit,
left_source_order,
);
let right_node = Node::new_satisfied_constraint(
db,
right,
ExplicitConstraint::Implicit,
right_source_order,
);
let left_node = Node::new_satisfied_constraint(db, left, left_source_order);
let right_node = Node::new_satisfied_constraint(db, right, right_source_order);
let validity = replacement.iff(db, left_node.or(db, right_node));
let constrained_original = self.and(db, validity);
let constrained_replacement = result.and(db, validity);
@ -1837,11 +1806,12 @@ impl<'db> Node<'db> {
Node::AlwaysTrue => write!(f, "always"),
Node::AlwaysFalse => write!(f, "never"),
Node::Interior(interior) => {
let constraint = interior.constraint(self.db);
write!(
f,
"{} {:?} {}/{}",
interior.constraint(self.db).display(self.db),
interior.explicit(self.db),
constraint.display(self.db),
constraint.explicit(self.db),
interior.source_order(self.db),
interior.max_source_order(self.db),
)?;
@ -1898,7 +1868,9 @@ impl<'db> RepresentativeBounds<'db> {
}
}
#[derive(Clone, Copy, Debug, Eq, PartialEq, Hash, get_size2::GetSize, salsa::Update)]
#[derive(
Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd, get_size2::GetSize, salsa::Update,
)]
pub(crate) enum ExplicitConstraint {
Implicit,
Explicit,
@ -1938,7 +1910,6 @@ struct InteriorNode<'db> {
constraint: ConstrainedTypeVar<'db>,
if_true: Node<'db>,
if_false: Node<'db>,
explicit: ExplicitConstraint,
/// Represents the order in which this node's constraint was added to the containing constraint
/// set, relative to all of the other constraints in the set. This starts off at 1 for a simple
@ -1963,7 +1934,6 @@ impl<'db> InteriorNode<'db> {
self.constraint(db),
self.if_true(db).negate(db),
self.if_false(db).negate(db),
self.explicit(db),
self.source_order(db),
)
}
@ -1980,7 +1950,6 @@ impl<'db> InteriorNode<'db> {
.or_inner(db, other.if_true(db), other_offset),
self.if_false(db)
.or_inner(db, other.if_false(db), other_offset),
self.explicit(db) & other.explicit(db),
self.source_order(db),
),
Ordering::Less => Node::new(
@ -1990,7 +1959,6 @@ impl<'db> InteriorNode<'db> {
.or_inner(db, Node::Interior(other), other_offset),
self.if_false(db)
.or_inner(db, Node::Interior(other), other_offset),
self.explicit(db),
self.source_order(db),
),
Ordering::Greater => Node::new(
@ -1998,7 +1966,6 @@ impl<'db> InteriorNode<'db> {
other_constraint,
Node::Interior(self).or_inner(db, other.if_true(db), other_offset),
Node::Interior(self).or_inner(db, other.if_false(db), other_offset),
other.explicit(db),
other.source_order(db) + other_offset,
),
}
@ -2016,7 +1983,6 @@ impl<'db> InteriorNode<'db> {
.and_inner(db, other.if_true(db), other_offset),
self.if_false(db)
.and_inner(db, other.if_false(db), other_offset),
self.explicit(db) & other.explicit(db),
self.source_order(db),
),
Ordering::Less => Node::new(
@ -2026,7 +1992,6 @@ impl<'db> InteriorNode<'db> {
.and_inner(db, Node::Interior(other), other_offset),
self.if_false(db)
.and_inner(db, Node::Interior(other), other_offset),
self.explicit(db),
self.source_order(db),
),
Ordering::Greater => Node::new(
@ -2034,7 +1999,6 @@ impl<'db> InteriorNode<'db> {
other_constraint,
Node::Interior(self).and_inner(db, other.if_true(db), other_offset),
Node::Interior(self).and_inner(db, other.if_false(db), other_offset),
other.explicit(db),
other.source_order(db) + other_offset,
),
}
@ -2052,7 +2016,6 @@ impl<'db> InteriorNode<'db> {
.iff_inner(db, other.if_true(db), other_offset),
self.if_false(db)
.iff_inner(db, other.if_false(db), other_offset),
self.explicit(db) & other.explicit(db),
self.source_order(db),
),
Ordering::Less => Node::new(
@ -2062,7 +2025,6 @@ impl<'db> InteriorNode<'db> {
.iff_inner(db, Node::Interior(other), other_offset),
self.if_false(db)
.iff_inner(db, Node::Interior(other), other_offset),
self.explicit(db),
self.source_order(db),
),
Ordering::Greater => Node::new(
@ -2070,7 +2032,6 @@ impl<'db> InteriorNode<'db> {
other_constraint,
Node::Interior(self).iff_inner(db, other.if_true(db), other_offset),
Node::Interior(self).iff_inner(db, other.if_false(db), other_offset),
other.explicit(db),
other.source_order(db) + other_offset,
),
}
@ -2140,7 +2101,6 @@ impl<'db> InteriorNode<'db> {
) -> Node<'db> {
let self_constraint = self.constraint(db);
let self_source_order = self.source_order(db);
let self_explicit = self.explicit(db);
if should_remove(self_constraint) {
// If we should remove constraints involving this typevar, then we replace this node
// with the OR of its if_false/if_true edges. That is, the result is true if there's
@ -2154,7 +2114,6 @@ impl<'db> InteriorNode<'db> {
db,
map,
self_constraint.when_true(),
self_explicit,
self_source_order,
|path, new_range| {
let branch =
@ -2167,15 +2126,10 @@ impl<'db> InteriorNode<'db> {
// removed!
!should_remove(assignment.constraint())
})
.fold(branch, |branch, (assignment, (explicit, source_order))| {
.fold(branch, |branch, (assignment, source_order)| {
branch.and(
db,
Node::new_satisfied_constraint(
db,
*assignment,
*explicit,
*source_order,
),
Node::new_satisfied_constraint(db, *assignment, *source_order),
)
})
},
@ -2186,7 +2140,6 @@ impl<'db> InteriorNode<'db> {
db,
map,
self_constraint.when_false(),
self_explicit,
self_source_order,
|path, new_range| {
let branch =
@ -2199,15 +2152,10 @@ impl<'db> InteriorNode<'db> {
// removed!
!should_remove(assignment.constraint())
})
.fold(branch, |branch, (assignment, (explicit, source_order))| {
.fold(branch, |branch, (assignment, source_order)| {
branch.and(
db,
Node::new_satisfied_constraint(
db,
*assignment,
*explicit,
*source_order,
),
Node::new_satisfied_constraint(db, *assignment, *source_order),
)
})
},
@ -2221,7 +2169,6 @@ impl<'db> InteriorNode<'db> {
db,
map,
self_constraint.when_true(),
self_explicit,
self_source_order,
|path, _| {
self.if_true(db)
@ -2234,7 +2181,6 @@ impl<'db> InteriorNode<'db> {
db,
map,
self_constraint.when_false(),
self_explicit,
self_source_order,
|path, _| {
self.if_false(db)
@ -2245,8 +2191,7 @@ impl<'db> InteriorNode<'db> {
// NB: We cannot use `Node::new` here, because the recursive calls might introduce new
// derived constraints into the result, and those constraints might appear before this
// one in the BDD ordering.
Node::new_constraint(db, self_constraint, self_explicit, self_source_order)
.ite(db, if_true, if_false)
Node::new_constraint(db, self_constraint, self_source_order).ite(db, if_true, if_false)
}
}
@ -2279,7 +2224,6 @@ impl<'db> InteriorNode<'db> {
self_constraint,
if_true,
if_false,
self.explicit(db),
self.source_order(db),
),
found_in_true || found_in_false,
@ -2410,28 +2354,26 @@ impl<'db> InteriorNode<'db> {
_ => continue,
};
let new_constraint =
ConstrainedTypeVar::new(db, constrained_typevar, new_lower, new_upper);
let new_constraint = ConstrainedTypeVar::new(
db,
constrained_typevar,
new_lower,
new_upper,
ExplicitConstraint::Implicit,
);
if seen_constraints.contains(&new_constraint) {
continue;
}
let new_node = Node::new_constraint(
db,
new_constraint,
ExplicitConstraint::Implicit,
next_source_order,
);
let new_node = Node::new_constraint(db, new_constraint, next_source_order);
next_source_order += 1;
let positive_left_node = Node::new_satisfied_constraint(
db,
left_constraint.when_true(),
ExplicitConstraint::Implicit,
left_source_order,
);
let positive_right_node = Node::new_satisfied_constraint(
db,
right_constraint.when_true(),
ExplicitConstraint::Implicit,
right_source_order,
);
let lhs = positive_left_node.and(db, positive_right_node);
@ -2482,13 +2424,11 @@ impl<'db> InteriorNode<'db> {
let positive_larger_node = Node::new_satisfied_constraint(
db,
larger_constraint.when_true(),
ExplicitConstraint::Implicit,
larger_source_order,
);
let negative_larger_node = Node::new_satisfied_constraint(
db,
larger_constraint.when_false(),
ExplicitConstraint::Implicit,
larger_source_order,
);
@ -2556,13 +2496,11 @@ impl<'db> InteriorNode<'db> {
let positive_intersection_node = Node::new_satisfied_constraint(
db,
intersection_constraint.when_true(),
ExplicitConstraint::Implicit,
next_source_order,
);
let negative_intersection_node = Node::new_satisfied_constraint(
db,
intersection_constraint.when_false(),
ExplicitConstraint::Implicit,
next_source_order,
);
next_source_order += 1;
@ -2570,26 +2508,22 @@ impl<'db> InteriorNode<'db> {
let positive_left_node = Node::new_satisfied_constraint(
db,
left_constraint.when_true(),
ExplicitConstraint::Implicit,
left_source_order,
);
let negative_left_node = Node::new_satisfied_constraint(
db,
left_constraint.when_false(),
ExplicitConstraint::Implicit,
left_source_order,
);
let positive_right_node = Node::new_satisfied_constraint(
db,
right_constraint.when_true(),
ExplicitConstraint::Implicit,
right_source_order,
);
let negative_right_node = Node::new_satisfied_constraint(
db,
right_constraint.when_false(),
ExplicitConstraint::Implicit,
right_source_order,
);
@ -2671,13 +2605,11 @@ impl<'db> InteriorNode<'db> {
let positive_left_node = Node::new_satisfied_constraint(
db,
left_constraint.when_true(),
ExplicitConstraint::Implicit,
left_source_order,
);
let positive_right_node = Node::new_satisfied_constraint(
db,
right_constraint.when_true(),
ExplicitConstraint::Implicit,
right_source_order,
);
@ -3051,21 +2983,35 @@ impl<'db> SequentMap<'db> {
// Case 1
(Type::TypeVar(lower_typevar), Type::TypeVar(upper_typevar)) => {
if !lower_typevar.is_same_typevar_as(db, upper_typevar) {
ConstrainedTypeVar::new(db, lower_typevar, Type::Never, upper)
ConstrainedTypeVar::new(
db,
lower_typevar,
Type::Never,
upper,
constraint.explicit(db),
)
} else {
return;
}
}
// Case 2
(Type::TypeVar(lower_typevar), _) => {
ConstrainedTypeVar::new(db, lower_typevar, Type::Never, upper)
}
(Type::TypeVar(lower_typevar), _) => ConstrainedTypeVar::new(
db,
lower_typevar,
Type::Never,
upper,
constraint.explicit(db),
),
// Case 3
(_, Type::TypeVar(upper_typevar)) => {
ConstrainedTypeVar::new(db, upper_typevar, lower, Type::object())
}
(_, Type::TypeVar(upper_typevar)) => ConstrainedTypeVar::new(
db,
upper_typevar,
lower,
Type::object(),
constraint.explicit(db),
),
_ => return,
};
@ -3179,8 +3125,13 @@ impl<'db> SequentMap<'db> {
_ => return,
};
let post_constraint =
ConstrainedTypeVar::new(db, constrained_typevar, new_lower, new_upper);
let post_constraint = ConstrainedTypeVar::new(
db,
constrained_typevar,
new_lower,
new_upper,
left_constraint.explicit(db) & right_constraint.explicit(db),
);
self.add_pair_implication(db, left_constraint, right_constraint, post_constraint);
self.enqueue_constraint(post_constraint);
}
@ -3202,14 +3153,28 @@ impl<'db> SequentMap<'db> {
(Type::TypeVar(bound_typevar), Type::TypeVar(other_bound_typevar))
if bound_typevar.is_same_typevar_as(db, other_bound_typevar) =>
{
ConstrainedTypeVar::new(db, bound_typevar, right_lower, right_upper)
}
(Type::TypeVar(bound_typevar), _) => {
ConstrainedTypeVar::new(db, bound_typevar, Type::Never, right_upper)
}
(_, Type::TypeVar(bound_typevar)) => {
ConstrainedTypeVar::new(db, bound_typevar, right_lower, Type::object())
ConstrainedTypeVar::new(
db,
bound_typevar,
right_lower,
right_upper,
left_constraint.explicit(db) & right_constraint.explicit(db),
)
}
(Type::TypeVar(bound_typevar), _) => ConstrainedTypeVar::new(
db,
bound_typevar,
Type::Never,
right_upper,
left_constraint.explicit(db) & right_constraint.explicit(db),
),
(_, Type::TypeVar(bound_typevar)) => ConstrainedTypeVar::new(
db,
bound_typevar,
right_lower,
Type::object(),
left_constraint.explicit(db) & right_constraint.explicit(db),
),
_ => return,
};
self.add_pair_implication(db, left_constraint, right_constraint, post_constraint);
@ -3356,7 +3321,7 @@ impl<'db> SequentMap<'db> {
/// traversing a BDD.
#[derive(Debug, Default)]
pub(crate) struct PathAssignments<'db> {
assignments: FxOrderMap<ConstraintAssignment<'db>, (ExplicitConstraint, usize)>,
assignments: FxOrderMap<ConstraintAssignment<'db>, usize>,
}
impl<'db> PathAssignments<'db> {
@ -3387,7 +3352,6 @@ impl<'db> PathAssignments<'db> {
db: &'db dyn Db,
map: &SequentMap<'db>,
assignment: ConstraintAssignment<'db>,
explicit: ExplicitConstraint,
source_order: usize,
f: impl FnOnce(&mut Self, Range<usize>) -> R,
) -> Option<R> {
@ -3406,7 +3370,7 @@ impl<'db> PathAssignments<'db> {
edge = %assignment.display(db),
"walk edge",
);
let found_conflict = self.add_assignment(db, map, assignment, explicit, source_order);
let found_conflict = self.add_assignment(db, map, assignment, source_order);
let result = if found_conflict.is_err() {
// If that results in the path now being impossible due to a contradiction, return
// without invoking the callback.
@ -3439,15 +3403,6 @@ impl<'db> PathAssignments<'db> {
self.assignments.contains_key(&assignment)
}
fn assignment_holds_explicitly(
&self,
assignment: ConstraintAssignment<'db>,
) -> Option<ExplicitConstraint> {
self.assignments
.get(&assignment)
.map(|(explicit, _)| *explicit)
}
/// Adds a new assignment, along with any derived information that we can infer from the new
/// assignment combined with the assignments we've already seen. If any of this causes the path
/// to become invalid, due to a contradiction, returns a [`PathAssignmentConflict`] error.
@ -3456,7 +3411,6 @@ impl<'db> PathAssignments<'db> {
db: &'db dyn Db,
map: &SequentMap<'db>,
assignment: ConstraintAssignment<'db>,
explicit: ExplicitConstraint,
source_order: usize,
) -> Result<(), PathAssignmentConflict> {
// First add this assignment. If it causes a conflict, return that as an error. If we've
@ -3473,11 +3427,7 @@ impl<'db> PathAssignments<'db> {
);
return Err(PathAssignmentConflict);
}
if self
.assignments
.insert(assignment, (explicit, source_order))
.is_some()
{
if self.assignments.insert(assignment, source_order).is_some() {
return Ok(());
}
@ -3531,31 +3481,18 @@ impl<'db> PathAssignments<'db> {
for ((ante1, ante2), posts) in &map.pair_implications {
for post in posts {
if let Some(ante1_explicit) = self.assignment_holds_explicitly(ante1.when_true())
&& let Some(ante2_explicit) =
self.assignment_holds_explicitly(ante2.when_true())
if self.assignment_holds(ante1.when_true())
&& self.assignment_holds(ante2.when_true())
{
self.add_assignment(
db,
map,
post.when_true(),
explicit & ante1_explicit & ante2_explicit,
source_order,
)?;
self.add_assignment(db, map, post.when_true(), source_order)?;
}
}
}
for (ante, posts) in &map.single_implications {
for post in posts {
if let Some(ante_explicit) = self.assignment_holds_explicitly(ante.when_true()) {
self.add_assignment(
db,
map,
post.when_true(),
explicit & ante_explicit,
source_order,
)?;
if self.assignment_holds(ante.when_true()) {
self.add_assignment(db, map, post.when_true(), source_order)?;
}
}
}