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track whether constraints are explicit or not

This commit is contained in:
Douglas Creager 2025-12-15 15:54:23 -05:00
parent 298e2dcb4e
commit c790aa7474
1 changed files with 268 additions and 52 deletions
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302
crates/ty_python_semantic/src/types/constraints.rs
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@ -69,7 +69,7 @@
use std::cell::RefCell;
use std::cmp::Ordering;
use std::fmt::Display;
use std::ops::Range;
use std::ops::{BitAnd, BitOr, Range};
use itertools::Itertools;
use rustc_hash::{FxHashMap, FxHashSet};
@ -205,7 +205,13 @@ impl<'db> ConstraintSet<'db> {
upper: Type<'db>,
) -> Self {
Self {
node: ConstrainedTypeVar::new_node(db, typevar, lower, upper),
node: ConstrainedTypeVar::new_node(
db,
typevar,
lower,
upper,
ExplicitConstraint::Explicit,
),
}
}
@ -501,13 +507,12 @@ impl get_size2::GetSize for ConstrainedTypeVar<'_> {}
#[salsa::tracked]
impl<'db> ConstrainedTypeVar<'db> {
/// Returns a new range constraint.
///
/// Panics if `lower` and `upper` are not both fully static.
fn new_node(
db: &'db dyn Db,
typevar: BoundTypeVarInstance<'db>,
mut lower: Type<'db>,
mut upper: Type<'db>,
explicit: ExplicitConstraint,
) -> Node<'db> {
// It's not useful for an upper bound to be an intersection type, or for a lower bound to
// be a union type. Because the following equivalences hold, we can break these bounds
@ -522,7 +527,7 @@ impl<'db> ConstrainedTypeVar<'db> {
for lower_element in lower_union.elements(db) {
result = result.and_with_offset(
db,
ConstrainedTypeVar::new_node(db, typevar, *lower_element, upper),
ConstrainedTypeVar::new_node(db, typevar, *lower_element, upper, explicit),
);
}
return result;
@ -537,13 +542,19 @@ impl<'db> ConstrainedTypeVar<'db> {
for upper_element in upper_intersection.iter_positive(db) {
result = result.and_with_offset(
db,
ConstrainedTypeVar::new_node(db, typevar, lower, upper_element),
ConstrainedTypeVar::new_node(db, typevar, lower, upper_element, explicit),
);
}
for upper_element in upper_intersection.iter_negative(db) {
result = result.and_with_offset(
db,
ConstrainedTypeVar::new_node(db, typevar, lower, upper_element.negate(db)),
ConstrainedTypeVar::new_node(
db,
typevar,
lower,
upper_element.negate(db),
explicit,
),
);
}
return result;
@ -576,6 +587,7 @@ impl<'db> ConstrainedTypeVar<'db> {
return Node::new_constraint(
db,
ConstrainedTypeVar::new(db, typevar, Type::Never, Type::object()),
explicit,
1,
)
.negate(db);
@ -628,6 +640,7 @@ impl<'db> ConstrainedTypeVar<'db> {
Type::TypeVar(bound),
Type::TypeVar(bound),
),
explicit,
1,
)
}
@ -639,11 +652,13 @@ impl<'db> ConstrainedTypeVar<'db> {
let lower = Node::new_constraint(
db,
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,
1,
);
lower.and(db, upper)
@ -654,12 +669,13 @@ impl<'db> ConstrainedTypeVar<'db> {
let lower = Node::new_constraint(
db,
ConstrainedTypeVar::new(db, lower, Type::Never, Type::TypeVar(typevar)),
explicit,
1,
);
let upper = if upper.is_object() {
Node::AlwaysTrue
} else {
Self::new_node(db, typevar, Type::Never, upper)
Self::new_node(db, typevar, Type::Never, upper, explicit)
};
lower.and(db, upper)
}
@ -669,17 +685,23 @@ impl<'db> ConstrainedTypeVar<'db> {
let lower = if lower.is_never() {
Node::AlwaysTrue
} else {
Self::new_node(db, typevar, lower, Type::object())
Self::new_node(db, typevar, lower, Type::object(), explicit)
};
let upper = Node::new_constraint(
db,
ConstrainedTypeVar::new(db, upper, Type::TypeVar(typevar), Type::object()),
explicit,
1,
);
lower.and(db, upper)
}
_ => Node::new_constraint(db, ConstrainedTypeVar::new(db, typevar, lower, upper), 1),
_ => Node::new_constraint(
db,
ConstrainedTypeVar::new(db, typevar, lower, upper),
explicit,
1,
),
}
}
@ -868,6 +890,7 @@ 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| {
@ -889,6 +912,7 @@ impl<'db> Node<'db> {
constraint,
if_true,
if_false,
explicit,
source_order,
max_source_order,
))
@ -899,6 +923,7 @@ impl<'db> Node<'db> {
fn new_constraint(
db: &'db dyn Db,
constraint: ConstrainedTypeVar<'db>,
explicit: ExplicitConstraint,
source_order: usize,
) -> Self {
Self::Interior(InteriorNode::new(
@ -906,6 +931,7 @@ impl<'db> Node<'db> {
constraint,
Node::AlwaysTrue,
Node::AlwaysFalse,
explicit,
source_order,
source_order,
))
@ -917,6 +943,7 @@ impl<'db> Node<'db> {
fn new_satisfied_constraint(
db: &'db dyn Db,
constraint: ConstraintAssignment<'db>,
explicit: ExplicitConstraint,
source_order: usize,
) -> Self {
match constraint {
@ -925,6 +952,7 @@ impl<'db> Node<'db> {
constraint,
Node::AlwaysTrue,
Node::AlwaysFalse,
explicit,
source_order,
source_order,
)),
@ -933,6 +961,7 @@ impl<'db> Node<'db> {
constraint,
Node::AlwaysFalse,
Node::AlwaysTrue,
explicit,
source_order,
source_order,
)),
@ -968,6 +997,7 @@ 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,
),
}
@ -1000,24 +1030,39 @@ 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(), source_order, |path, _| {
.walk_edge(
db,
map,
constraint.when_true(),
explicit,
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(), source_order, |path, _| {
path.walk_edge(
db,
map,
constraint.when_false(),
explicit,
source_order,
|path, _| {
interior
.if_false(db)
.is_always_satisfied_inner(db, map, path)
})
},
)
.unwrap_or(true)
}
}
@ -1050,22 +1095,35 @@ 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(), source_order, |path, _| {
interior.if_true(db).is_never_satisfied_inner(db, map, path)
})
.walk_edge(
db,
map,
constraint.when_true(),
explicit,
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(), source_order, |path, _| {
path.walk_edge(
db,
map,
constraint.when_false(),
explicit,
source_order,
|path, _| {
interior
.if_false(db)
.is_never_satisfied_inner(db, map, path)
})
},
)
.unwrap_or(true)
}
}
@ -1108,6 +1166,7 @@ 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(
@ -1115,6 +1174,7 @@ 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),
@ -1148,6 +1208,7 @@ 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(
@ -1155,6 +1216,7 @@ 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),
@ -1199,6 +1261,7 @@ 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(
@ -1206,6 +1269,7 @@ 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),
@ -1234,12 +1298,14 @@ impl<'db> Node<'db> {
bound_typevar,
Type::Never,
rhs.bottom_materialization(db),
ExplicitConstraint::Implicit,
),
(_, Type::TypeVar(bound_typevar)) => ConstrainedTypeVar::new_node(
db,
bound_typevar,
lhs.top_materialization(db),
Type::object(),
ExplicitConstraint::Implicit,
),
_ => panic!("at least one type should be a typevar"),
};
@ -1529,8 +1595,18 @@ 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, left_source_order);
let right_node = Node::new_satisfied_constraint(db, right, right_source_order);
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 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);
@ -1595,8 +1671,18 @@ 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, left_source_order);
let right_node = Node::new_satisfied_constraint(db, right, right_source_order);
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 validity = replacement.iff(db, left_node.or(db, right_node));
let constrained_original = self.and(db, validity);
let constrained_replacement = result.and(db, validity);
@ -1753,8 +1839,9 @@ impl<'db> Node<'db> {
Node::Interior(interior) => {
write!(
f,
"{} {}/{}",
"{} {:?} {}/{}",
interior.constraint(self.db).display(self.db),
interior.explicit(self.db),
interior.source_order(self.db),
interior.max_source_order(self.db),
)?;
@ -1811,12 +1898,47 @@ impl<'db> RepresentativeBounds<'db> {
}
}
#[derive(Clone, Copy, Debug, Eq, PartialEq, Hash, get_size2::GetSize, salsa::Update)]
pub(crate) enum ExplicitConstraint {
Implicit,
Explicit,
}
impl BitAnd for ExplicitConstraint {
type Output = Self;
fn bitand(self, other: Self) -> Self {
match (self, other) {
(ExplicitConstraint::Explicit, ExplicitConstraint::Explicit) => {
ExplicitConstraint::Explicit
}
(ExplicitConstraint::Implicit, _) | (_, ExplicitConstraint::Implicit) => {
ExplicitConstraint::Implicit
}
}
}
}
impl BitOr for ExplicitConstraint {
type Output = Self;
fn bitor(self, other: Self) -> Self {
match (self, other) {
(ExplicitConstraint::Implicit, ExplicitConstraint::Implicit) => {
ExplicitConstraint::Implicit
}
(ExplicitConstraint::Explicit, _) | (_, ExplicitConstraint::Explicit) => {
ExplicitConstraint::Explicit
}
}
}
}
/// An interior node of a BDD
#[salsa::interned(debug, heap_size=ruff_memory_usage::heap_size)]
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
@ -1841,6 +1963,7 @@ 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),
)
}
@ -1857,6 +1980,7 @@ 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(
@ -1866,6 +1990,7 @@ 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(
@ -1873,6 +1998,7 @@ 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,
),
}
@ -1890,6 +2016,7 @@ 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(
@ -1899,6 +2026,7 @@ 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(
@ -1906,6 +2034,7 @@ 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,
),
}
@ -1923,6 +2052,7 @@ 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(
@ -1932,6 +2062,7 @@ 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(
@ -1939,6 +2070,7 @@ 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,
),
}
@ -2008,6 +2140,7 @@ 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
@ -2021,6 +2154,7 @@ impl<'db> InteriorNode<'db> {
db,
map,
self_constraint.when_true(),
self_explicit,
self_source_order,
|path, new_range| {
let branch =
@ -2033,10 +2167,15 @@ impl<'db> InteriorNode<'db> {
// removed!
!should_remove(assignment.constraint())
})
.fold(branch, |branch, (assignment, source_order)| {
.fold(branch, |branch, (assignment, (explicit, source_order))| {
branch.and(
db,
Node::new_satisfied_constraint(db, *assignment, *source_order),
Node::new_satisfied_constraint(
db,
*assignment,
*explicit,
*source_order,
),
)
})
},
@ -2047,6 +2186,7 @@ impl<'db> InteriorNode<'db> {
db,
map,
self_constraint.when_false(),
self_explicit,
self_source_order,
|path, new_range| {
let branch =
@ -2059,10 +2199,15 @@ impl<'db> InteriorNode<'db> {
// removed!
!should_remove(assignment.constraint())
})
.fold(branch, |branch, (assignment, source_order)| {
.fold(branch, |branch, (assignment, (explicit, source_order))| {
branch.and(
db,
Node::new_satisfied_constraint(db, *assignment, *source_order),
Node::new_satisfied_constraint(
db,
*assignment,
*explicit,
*source_order,
),
)
})
},
@ -2076,6 +2221,7 @@ impl<'db> InteriorNode<'db> {
db,
map,
self_constraint.when_true(),
self_explicit,
self_source_order,
|path, _| {
self.if_true(db)
@ -2088,6 +2234,7 @@ impl<'db> InteriorNode<'db> {
db,
map,
self_constraint.when_false(),
self_explicit,
self_source_order,
|path, _| {
self.if_false(db)
@ -2098,7 +2245,7 @@ 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.source_order(db))
Node::new_constraint(db, self_constraint, self_explicit, self_source_order)
.ite(db, if_true, if_false)
}
}
@ -2132,6 +2279,7 @@ impl<'db> InteriorNode<'db> {
self_constraint,
if_true,
if_false,
self.explicit(db),
self.source_order(db),
),
found_in_true || found_in_false,
@ -2267,16 +2415,23 @@ impl<'db> InteriorNode<'db> {
if seen_constraints.contains(&new_constraint) {
continue;
}
let new_node = Node::new_constraint(db, new_constraint, next_source_order);
let new_node = Node::new_constraint(
db,
new_constraint,
ExplicitConstraint::Implicit,
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);
@ -2327,11 +2482,13 @@ 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,
);
@ -2399,11 +2556,13 @@ 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;
@ -2411,22 +2570,26 @@ 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,
);
@ -2508,11 +2671,13 @@ 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,
);
@ -3191,7 +3356,7 @@ impl<'db> SequentMap<'db> {
/// traversing a BDD.
#[derive(Debug, Default)]
pub(crate) struct PathAssignments<'db> {
assignments: FxOrderMap<ConstraintAssignment<'db>, usize>,
assignments: FxOrderMap<ConstraintAssignment<'db>, (ExplicitConstraint, usize)>,
}
impl<'db> PathAssignments<'db> {
@ -3222,6 +3387,7 @@ 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> {
@ -3240,7 +3406,7 @@ impl<'db> PathAssignments<'db> {
edge = %assignment.display(db),
"walk edge",
);
let found_conflict = self.add_assignment(db, map, assignment, source_order);
let found_conflict = self.add_assignment(db, map, assignment, explicit, 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.
@ -3273,6 +3439,15 @@ 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.
@ -3281,6 +3456,7 @@ 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
@ -3297,7 +3473,11 @@ impl<'db> PathAssignments<'db> {
);
return Err(PathAssignmentConflict);
}
if self.assignments.insert(assignment, source_order).is_some() {
if self
.assignments
.insert(assignment, (explicit, source_order))
.is_some()
{
return Ok(());
}
@ -3351,18 +3531,31 @@ impl<'db> PathAssignments<'db> {
for ((ante1, ante2), posts) in &map.pair_implications {
for post in posts {
if self.assignment_holds(ante1.when_true())
&& self.assignment_holds(ante2.when_true())
if let Some(ante1_explicit) = self.assignment_holds_explicitly(ante1.when_true())
&& let Some(ante2_explicit) =
self.assignment_holds_explicitly(ante2.when_true())
{
self.add_assignment(db, map, post.when_true(), source_order)?;
self.add_assignment(
db,
map,
post.when_true(),
explicit & ante1_explicit & ante2_explicit,
source_order,
)?;
}
}
}
for (ante, posts) in &map.single_implications {
for post in posts {
if self.assignment_holds(ante.when_true()) {
self.add_assignment(db, map, post.when_true(), source_order)?;
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,
)?;
}
}
}
@ -3615,7 +3808,13 @@ impl<'db> BoundTypeVarInstance<'db> {
None => Node::AlwaysTrue,
Some(TypeVarBoundOrConstraints::UpperBound(bound)) => {
let bound = bound.top_materialization(db);
ConstrainedTypeVar::new_node(db, self, Type::Never, bound)
ConstrainedTypeVar::new_node(
db,
self,
Type::Never,
bound,
ExplicitConstraint::Implicit,
)
}
Some(TypeVarBoundOrConstraints::Constraints(constraints)) => {
let mut specializations = Node::AlwaysFalse;
@ -3624,7 +3823,13 @@ impl<'db> BoundTypeVarInstance<'db> {
let constraint_upper = constraint.top_materialization(db);
specializations = specializations.or_with_offset(
db,
ConstrainedTypeVar::new_node(db, self, constraint_lower, constraint_upper),
ConstrainedTypeVar::new_node(
db,
self,
constraint_lower,
constraint_upper,
ExplicitConstraint::Implicit,
),
);
}
specializations
@ -3659,7 +3864,13 @@ impl<'db> BoundTypeVarInstance<'db> {
Some(TypeVarBoundOrConstraints::UpperBound(bound)) => {
let bound = bound.bottom_materialization(db);
(
ConstrainedTypeVar::new_node(db, self, Type::Never, bound),
ConstrainedTypeVar::new_node(
db,
self,
Type::Never,
bound,
ExplicitConstraint::Implicit,
),
Vec::new(),
)
}
@ -3669,8 +3880,13 @@ impl<'db> BoundTypeVarInstance<'db> {
for constraint in constraints.elements(db) {
let constraint_lower = constraint.bottom_materialization(db);
let constraint_upper = constraint.top_materialization(db);
let constraint =
ConstrainedTypeVar::new_node(db, self, constraint_lower, constraint_upper);
let constraint = ConstrainedTypeVar::new_node(
db,
self,
constraint_lower,
constraint_upper,
ExplicitConstraint::Implicit,
);
if constraint_lower == constraint_upper {
non_gradual_constraints =
non_gradual_constraints.or_with_offset(db, constraint);