tame/tamer/src/asg/air/test.rs

805 lines
25 KiB
Rust

// Tests for ASG IR
//
// Copyright (C) 2014-2023 Ryan Specialty, LLC.
//
// This file is part of TAME.
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
//! These are tested as if they are another API directly atop of the ASG,
//! since that is how they are used.
use super::super::graph::object::{ObjectKind, ObjectRelTo};
use super::super::Ident;
use super::*;
use crate::{
parse::{ParseError, Parsed},
span::dummy::*,
};
use std::assert_matches::assert_matches;
type Sut = AirAggregate;
#[test]
fn ident_decl() {
let id = SPair("foo".into(), S1);
let kind = IdentKind::Tpl;
let src = Source {
src: Some("test/decl".into()),
..Default::default()
};
let toks = vec![Air::IdentDecl(id, kind.clone(), src.clone())].into_iter();
let mut sut = Sut::parse(toks);
assert_eq!(Some(Ok(Parsed::Incomplete)), sut.next());
let asg = sut.finalize().unwrap().into_context();
let ident_node = asg.lookup(id).expect("identifier was not added to graph");
let ident = asg.get(ident_node).unwrap();
assert_eq!(
Ok(ident),
Ident::declare(id)
.resolve(S1, kind.clone(), src.clone())
.as_ref(),
);
// Re-instantiate the parser and test an error by attempting to
// redeclare the same identifier.
let bad_toks =
vec![Air::IdentDecl(SPair(id.symbol(), S2), kind, src)].into_iter();
let mut sut = Sut::parse_with_context(bad_toks, asg);
assert_matches!(
sut.next(),
Some(Err(ParseError::StateError(AsgError::IdentTransition(_)))),
);
}
#[test]
fn ident_extern_decl() {
let id = SPair("foo".into(), S1);
let kind = IdentKind::Tpl;
let src = Source {
src: Some("test/decl-extern".into()),
..Default::default()
};
let toks =
vec![Air::IdentExternDecl(id, kind.clone(), src.clone())].into_iter();
let mut sut = Sut::parse(toks);
assert_eq!(Some(Ok(Parsed::Incomplete)), sut.next());
let asg = sut.finalize().unwrap().into_context();
let ident_node = asg.lookup(id).expect("identifier was not added to graph");
let ident = asg.get(ident_node).unwrap();
assert_eq!(
Ok(ident),
Ident::declare(id).extern_(S1, kind, src.clone()).as_ref(),
);
// Re-instantiate the parser and test an error by attempting to
// redeclare with a different kind.
let different_kind = IdentKind::Meta;
let bad_toks = vec![Air::IdentExternDecl(
SPair(id.symbol(), S2),
different_kind,
src,
)]
.into_iter();
let mut sut = Sut::parse_with_context(bad_toks, asg);
assert_matches!(
sut.next(),
Some(Err(ParseError::StateError(AsgError::IdentTransition(_)))),
);
}
#[test]
fn ident_dep() {
let id = SPair("foo".into(), S1);
let dep = SPair("dep".into(), S2);
let toks = vec![Air::IdentDep(id, dep)].into_iter();
let mut sut = Sut::parse(toks);
assert_eq!(Some(Ok(Parsed::Incomplete)), sut.next());
let asg = sut.finalize().unwrap().into_context();
let ident_node = asg.lookup(id).expect("identifier was not added to graph");
let dep_node = asg.lookup(dep).expect("dep was not added to graph");
assert!(asg.has_dep(ident_node, dep_node));
}
#[test]
fn ident_fragment() {
let id = SPair("frag".into(), S1);
let kind = IdentKind::Tpl;
let src = Source {
src: Some("test/frag".into()),
..Default::default()
};
let frag = "fragment text".into();
let toks = vec![
// Identifier must be declared before it can be given a
// fragment.
Air::IdentDecl(id, kind.clone(), src.clone()),
Air::IdentFragment(id, frag),
]
.into_iter();
let mut sut = Sut::parse(toks);
assert_eq!(Some(Ok(Parsed::Incomplete)), sut.next()); // IdentDecl
assert_eq!(Some(Ok(Parsed::Incomplete)), sut.next()); // IdentFragment
let asg = sut.finalize().unwrap().into_context();
let ident_node = asg.lookup(id).expect("identifier was not added to graph");
let ident = asg.get(ident_node).unwrap();
assert_eq!(
Ok(ident),
Ident::declare(id)
.resolve(S1, kind.clone(), src.clone())
.and_then(|resolved| resolved.set_fragment(frag))
.as_ref(),
);
// Re-instantiate the parser and test an error by attempting to
// re-set the fragment.
let bad_toks = vec![Air::IdentFragment(id, frag)].into_iter();
let mut sut = Sut::parse_with_context(bad_toks, asg);
assert_matches!(
sut.next(),
Some(Err(ParseError::StateError(AsgError::IdentTransition(_)))),
);
}
// Adding a root before the identifier exists should add a
// `Ident::Missing`.
#[test]
fn ident_root_missing() {
let id = SPair("toroot".into(), S1);
let toks = vec![Air::IdentRoot(id)].into_iter();
let mut sut = Sut::parse(toks);
assert_eq!(Some(Ok(Parsed::Incomplete)), sut.next());
let asg = sut.finalize().unwrap().into_context();
let ident_node = asg
.lookup(id)
.expect("identifier was not added to the graph");
let ident = asg.get(ident_node).unwrap();
// The identifier did not previously exist,
// and so a missing node is created as a placeholder.
assert_eq!(&Ident::Missing(id), ident);
// And that missing identifier should be rooted.
assert!(asg.is_rooted(ident_node));
}
#[test]
fn ident_root_existing() {
let id = SPair("toroot".into(), S1);
let kind = IdentKind::Tpl;
let src = Source {
src: Some("test/root-existing".into()),
..Default::default()
};
// Ensure that it won't auto-root based on the kind,
// otherwise we won't be testing the right thing.
assert!(!kind.is_auto_root());
let toks = vec![
Air::IdentDecl(id, kind.clone(), src.clone()),
Air::IdentRoot(SPair(id.symbol(), S2)),
]
.into_iter();
let mut sut = Sut::parse(toks);
assert_eq!(Some(Ok(Parsed::Incomplete)), sut.next()); // IdentDecl
assert_eq!(Some(Ok(Parsed::Incomplete)), sut.next()); // IdentRoot
let asg = sut.finalize().unwrap().into_context();
let ident_node = asg
.lookup(id)
.expect("identifier was not added to the graph");
let ident = asg.get(ident_node).unwrap();
// The previously-declared identifier...
assert_eq!(
Ok(ident),
Ident::declare(id)
.resolve(S1, kind.clone(), src.clone())
.as_ref()
);
// ...should have been subsequently rooted.
assert!(asg.is_rooted(ident_node));
}
#[test]
fn expr_empty_ident() {
let id = SPair("foo".into(), S2);
let toks = vec![
Air::OpenExpr(ExprOp::Sum, S1),
Air::IdentExpr(id),
Air::CloseExpr(S3),
];
let mut sut = Sut::parse(toks.into_iter());
assert!(sut.all(|x| x.is_ok()));
let asg = sut.finalize().unwrap().into_context();
// The expression should have been bound to this identifier so that
// we're able to retrieve it from the graph by name.
let expr = asg.expect_ident_obj::<Expr>(id);
assert_eq!(expr.span(), S1.merge(S3).unwrap());
}
#[test]
fn expr_non_empty_ident_root() {
let id_a = SPair("foo".into(), S2);
let id_b = SPair("bar".into(), S2);
let toks = vec![
Air::OpenExpr(ExprOp::Sum, S1),
// Identifier while still empty...
Air::IdentExpr(id_a),
Air::OpenExpr(ExprOp::Sum, S3),
// (note that the inner expression _does not_ have an ident binding)
Air::CloseExpr(S4),
// ...and an identifier non-empty.
Air::IdentExpr(id_b),
Air::CloseExpr(S6),
];
let mut sut = Sut::parse(toks.into_iter());
assert!(sut.all(|x| x.is_ok()));
let asg = sut.finalize().unwrap().into_context();
let expr_a = asg.expect_ident_obj::<Expr>(id_a);
assert_eq!(expr_a.span(), S1.merge(S6).unwrap());
// Identifiers should reference the same expression.
let expr_b = asg.expect_ident_obj::<Expr>(id_b);
assert_eq!(expr_a, expr_b);
}
// Binding an identifier after a child expression means that the parser is
// creating an expression that is a child of a dangling expression,
// which only becomes reachable at the end.
#[test]
fn expr_non_empty_bind_only_after() {
let id = SPair("foo".into(), S2);
let toks = vec![
Air::OpenExpr(ExprOp::Sum, S1),
// Expression root is still dangling at this point.
Air::OpenExpr(ExprOp::Sum, S2),
Air::CloseExpr(S3),
// We only bind an identifier _after_ we've created the expression,
// which should cause the still-dangling root to become
// reachable.
Air::IdentExpr(id),
Air::CloseExpr(S5),
];
let mut sut = Sut::parse(toks.into_iter());
assert!(sut.all(|x| x.is_ok()));
let asg = sut.finalize().unwrap().into_context();
let expr = asg.expect_ident_obj::<Expr>(id);
assert_eq!(expr.span(), S1.merge(S5).unwrap());
}
// Danging expressions are unreachable and therefore not useful
// constructions.
// Prohibit them,
// since they're either mistakes or misconceptions.
#[test]
fn expr_dangling_no_subexpr() {
let toks = vec![
Air::OpenExpr(ExprOp::Sum, S1),
// No `IdentExpr`,
// so this expression is dangling.
Air::CloseExpr(S2),
];
// The error span should encompass the entire expression.
let full_span = S1.merge(S2).unwrap();
assert_eq!(
vec![
Ok(Parsed::Incomplete),
Err(ParseError::StateError(AsgError::DanglingExpr(full_span)))
],
Sut::parse(toks.into_iter()).collect::<Vec<_>>(),
);
}
#[test]
fn expr_dangling_with_subexpr() {
let toks = vec![
Air::OpenExpr(ExprOp::Sum, S1),
// Expression root is still dangling at this point.
Air::OpenExpr(ExprOp::Sum, S2),
Air::CloseExpr(S3),
// Still no ident binding,
// so root should still be dangling.
Air::CloseExpr(S4),
];
let full_span = S1.merge(S4).unwrap();
assert_eq!(
vec![
Ok(Parsed::Incomplete),
Ok(Parsed::Incomplete),
Ok(Parsed::Incomplete),
Err(ParseError::StateError(AsgError::DanglingExpr(full_span)))
],
Sut::parse(toks.into_iter()).collect::<Vec<_>>(),
);
}
#[test]
fn expr_dangling_with_subexpr_ident() {
let id = SPair("foo".into(), S3);
let toks = vec![
Air::OpenExpr(ExprOp::Sum, S1),
// Expression root is still dangling at this point.
Air::OpenExpr(ExprOp::Sum, S2),
// The _inner_ expression receives an identifier,
// but that should have no impact on the dangling status of the
// root,
// especially given that subexpressions are always reachable
// anyway.
Air::IdentExpr(id),
Air::CloseExpr(S4),
// But the root still has no ident binding,
// and so should still be dangling.
Air::CloseExpr(S5),
];
let full_span = S1.merge(S5).unwrap();
assert_eq!(
vec![
Ok(Parsed::Incomplete),
Ok(Parsed::Incomplete),
Ok(Parsed::Incomplete),
Ok(Parsed::Incomplete),
Err(ParseError::StateError(AsgError::DanglingExpr(full_span)))
],
Sut::parse(toks.into_iter()).collect::<Vec<_>>(),
);
}
// Ensure that the parser correctly recognizes dangling expressions after
// having encountered a reachable expression.
// Ideally the parser will have been written to make this impossible,
// but this also protects against potential future breakages.
#[test]
fn expr_reachable_subsequent_dangling() {
let id = SPair("foo".into(), S2);
let toks = vec![
// Reachable
Air::OpenExpr(ExprOp::Sum, S1),
Air::IdentExpr(id),
Air::CloseExpr(S3),
// Dangling
Air::OpenExpr(ExprOp::Sum, S4),
Air::CloseExpr(S5),
];
// The error span should encompass the entire expression.
// TODO: ...let's actually have something inside this expression.
let second_span = S4.merge(S5).unwrap();
assert_eq!(
vec![
Ok(Parsed::Incomplete),
Ok(Parsed::Incomplete),
Ok(Parsed::Incomplete),
Ok(Parsed::Incomplete),
Err(ParseError::StateError(AsgError::DanglingExpr(second_span)))
],
Sut::parse(toks.into_iter()).collect::<Vec<_>>(),
);
}
// Recovery from dangling expression.
#[test]
fn recovery_expr_reachable_after_dangling() {
let id = SPair("foo".into(), S4);
let toks = vec![
// Dangling
Air::OpenExpr(ExprOp::Sum, S1),
Air::CloseExpr(S2),
// Reachable, after error from dangling.
Air::OpenExpr(ExprOp::Sum, S3),
Air::IdentExpr(id),
Air::CloseExpr(S5),
];
// The error span should encompass the entire expression.
let err_span = S1.merge(S2).unwrap();
let mut sut = Sut::parse(toks.into_iter());
assert_eq!(
vec![
Ok(Parsed::Incomplete),
Err(ParseError::StateError(AsgError::DanglingExpr(err_span))),
// Recovery allows us to continue at this point with the next
// expression.
Ok(Parsed::Incomplete),
Ok(Parsed::Incomplete),
Ok(Parsed::Incomplete),
],
sut.by_ref().collect::<Vec<_>>(),
);
let asg = sut.finalize().unwrap().into_context();
// Let's make sure that we _actually_ added it to the graph,
// despite the previous error.
let expr = asg.expect_ident_obj::<Expr>(id);
assert_eq!(expr.span(), S3.merge(S5).unwrap());
// The dangling expression may or may not be on the graph,
// but it doesn't matter;
// we cannot reference it
// (unless we break abstraction and walk the underlying graph).
// Let's leave this undefined so that we have flexibility in what we
// decide to do in the future.
// So we end here.
}
#[test]
fn expr_close_unbalanced() {
let id = SPair("foo".into(), S3);
let toks = vec![
// Close before _any_ open.
Air::CloseExpr(S1),
// Should recover,
// allowing for a normal expr.
Air::OpenExpr(ExprOp::Sum, S2),
Air::IdentExpr(id),
Air::CloseExpr(S4),
// And now an extra close _after_ a valid expr.
Air::CloseExpr(S5),
];
let mut sut = Sut::parse(toks.into_iter());
assert_eq!(
vec![
Err(ParseError::StateError(AsgError::UnbalancedExpr(S1))),
// Recovery should allow us to continue.
Ok(Parsed::Incomplete), // OpenExpr
Ok(Parsed::Incomplete), // IdentExpr
Ok(Parsed::Incomplete), // CloseExpr
// Another error after a successful expression.
Err(ParseError::StateError(AsgError::UnbalancedExpr(S5))),
],
sut.by_ref().collect::<Vec<_>>(),
);
let asg = sut.finalize().unwrap().into_context();
// Just verify that the expression was successfully added after recovery.
let expr = asg.expect_ident_obj::<Expr>(id);
assert_eq!(expr.span(), S2.merge(S4).unwrap());
}
#[test]
fn expr_bind_to_empty() {
let id_noexpr_a = SPair("noexpr_a".into(), S1);
let id_good = SPair("noexpr".into(), S3);
let id_noexpr_b = SPair("noexpr_b".into(), S5);
let toks = vec![
// No open expression to bind to.
Air::IdentExpr(id_noexpr_a),
// Post-recovery create an expression.
Air::OpenExpr(ExprOp::Sum, S2),
Air::IdentExpr(id_good),
Air::CloseExpr(S4),
// Once again we have nothing to bind to.
Air::IdentExpr(id_noexpr_b),
];
let mut sut = Sut::parse(toks.into_iter());
assert_eq!(
vec![
Err(ParseError::StateError(AsgError::InvalidExprBindContext(
id_noexpr_a
))),
// Recovery should allow us to continue.
Ok(Parsed::Incomplete), // OpenExpr
Ok(Parsed::Incomplete), // IdentExpr
Ok(Parsed::Incomplete), // CloseExpr
// Another error after a successful expression.
Err(ParseError::StateError(AsgError::InvalidExprBindContext(
id_noexpr_b
))),
],
sut.by_ref().collect::<Vec<_>>(),
);
let asg = sut.finalize().unwrap().into_context();
// Neither of the identifiers outside of expressions should exist on the
// graph.
assert_eq!(None, asg.get_ident_obj::<Expr>(id_noexpr_a));
assert_eq!(None, asg.get_ident_obj::<Expr>(id_noexpr_b));
// Verify that the expression was successfully added after recovery.
let expr = asg.expect_ident_obj::<Expr>(id_good);
assert_eq!(expr.span(), S2.merge(S4).unwrap());
}
// Subexpressions should not only have edges to their parent,
// but those edges ought to be ordered,
// allowing TAME to handle non-commutative expressions.
// We must further understand the relative order in which edges are stored
// for non-associative expressions.
#[test]
fn sibling_subexprs_have_ordered_edges_to_parent() {
let id_root = SPair("root".into(), S1);
let toks = vec![
Air::OpenExpr(ExprOp::Sum, S1),
// Identify the root so that it is not dangling.
Air::IdentExpr(id_root),
// Sibling A
Air::OpenExpr(ExprOp::Sum, S3),
Air::CloseExpr(S4),
// Sibling B
Air::OpenExpr(ExprOp::Sum, S5),
Air::CloseExpr(S6),
// Sibling C
Air::OpenExpr(ExprOp::Sum, S7),
Air::CloseExpr(S8),
Air::CloseExpr(S9),
];
let asg = asg_from_toks(toks);
// The root is the parent expression that should contain edges to each
// subexpression
// (the siblings above).
// Note that we retrieve its _index_,
// not the object itself.
let oi_root = asg.expect_ident_oi::<Expr>(id_root);
let siblings = oi_root
.edges::<Expr>(&asg)
.map(|oi| oi.resolve(&asg))
.collect::<Vec<_>>();
// The reversal here is an implementation detail with regards to how
// Petgraph stores its edges as effectively linked lists,
// using node indices instead of pointers.
// It is very important that we understand this behavior.
assert_eq!(siblings.len(), 3);
assert_eq!(siblings[2].span(), S3.merge(S4).unwrap());
assert_eq!(siblings[1].span(), S5.merge(S6).unwrap());
assert_eq!(siblings[0].span(), S7.merge(S8).unwrap());
}
#[test]
fn nested_subexprs_related_to_relative_parent() {
let id_root = SPair("root".into(), S1);
let id_suba = SPair("suba".into(), S2);
let toks = vec![
Air::OpenExpr(ExprOp::Sum, S1), // 0
Air::IdentExpr(id_root),
Air::OpenExpr(ExprOp::Sum, S2), // 1
Air::IdentExpr(id_suba),
Air::OpenExpr(ExprOp::Sum, S3), // 2
Air::CloseExpr(S4),
Air::CloseExpr(S5),
Air::CloseExpr(S6),
];
let asg = asg_from_toks(toks);
let oi_0 = asg.expect_ident_oi::<Expr>(id_root);
let subexprs_0 = collect_subexprs(&asg, oi_0);
// Subexpr 1
assert_eq!(subexprs_0.len(), 1);
let (oi_1, subexpr_1) = subexprs_0[0];
assert_eq!(subexpr_1.span(), S2.merge(S5).unwrap());
let subexprs_1 = collect_subexprs(&asg, oi_1);
// Subexpr 2
assert_eq!(subexprs_1.len(), 1);
let (_, subexpr_2) = subexprs_1[0];
assert_eq!(subexpr_2.span(), S3.merge(S4).unwrap());
}
#[test]
fn expr_redefine_ident() {
// Same identifier but with different spans
// (which would be the case in the real world).
let id_first = SPair("foo".into(), S2);
let id_dup = SPair("foo".into(), S3);
let toks = vec![
Air::OpenExpr(ExprOp::Sum, S1),
Air::IdentExpr(id_first),
Air::OpenExpr(ExprOp::Sum, S3),
Air::IdentExpr(id_dup),
Air::CloseExpr(S4),
Air::CloseExpr(S5),
];
let mut sut = Sut::parse(toks.into_iter());
assert_eq!(
vec![
Ok(Parsed::Incomplete), // OpenExpr
Ok(Parsed::Incomplete), // IdentExpr (first)
Ok(Parsed::Incomplete), // OpenExpr
Err(ParseError::StateError(AsgError::IdentRedefine(
id_first,
id_dup.span(),
))),
// RECOVERY: Ignore the attempt to redefine and continue.
Ok(Parsed::Incomplete), // CloseExpr
Ok(Parsed::Incomplete), // CloseExpr
],
sut.by_ref().collect::<Vec<_>>(),
);
let asg = sut.finalize().unwrap().into_context();
// The identifier should continue to reference the first expression.
let expr = asg.expect_ident_obj::<Expr>(id_first);
assert_eq!(expr.span(), S1.merge(S5).unwrap());
}
// Similar to the above test,
// but with two entirely separate expressions,
// such that a failure to identify an expression ought to leave it in an
// unreachable state.
#[test]
fn expr_still_dangling_on_redefine() {
// Same identifier but with different spans
// (which would be the case in the real world).
let id_first = SPair("foo".into(), S2);
let id_dup = SPair("foo".into(), S5);
let id_dup2 = SPair("foo".into(), S8);
let id_second = SPair("bar".into(), S9);
let toks = vec![
// First expr (OK)
Air::OpenExpr(ExprOp::Sum, S1),
Air::IdentExpr(id_first),
Air::CloseExpr(S3),
// Second expr should still dangle due to use of duplicate
// identifier
Air::OpenExpr(ExprOp::Sum, S4),
Air::IdentExpr(id_dup),
Air::CloseExpr(S6),
// Third expr will error on redefine but then be successful.
// This probably won't happen in practice with TAME's original
// source language,
// but could happen at e.g. a REPL.
Air::OpenExpr(ExprOp::Sum, S7),
Air::IdentExpr(id_dup2), // fail
Air::IdentExpr(id_second), // succeed
Air::CloseExpr(S10),
];
let mut sut = Sut::parse(toks.into_iter());
assert_eq!(
vec![
Ok(Parsed::Incomplete), // OpenExpr
Ok(Parsed::Incomplete), // IdentExpr (first)
Ok(Parsed::Incomplete), // CloseExpr
// Beginning of second expression
Ok(Parsed::Incomplete), // OpenExpr
Err(ParseError::StateError(AsgError::IdentRedefine(
id_first,
id_dup.span(),
))),
// RECOVERY: Ignore the attempt to redefine and continue.
// ...but then immediately fail _again_ because we've closed a
// dangling expression.
Err(ParseError::StateError(AsgError::DanglingExpr(
S4.merge(S6).unwrap()
))),
// RECOVERY: But we'll continue onto one final expression,
// which we will fail to define but then subsequently define
// successfully.
Ok(Parsed::Incomplete), // OpenExpr
Err(ParseError::StateError(AsgError::IdentRedefine(
id_first,
id_dup2.span(),
))),
// RECOVERY: Despite the initial failure,
// we can now re-attempt to bind with a unique id.
Ok(Parsed::Incomplete), // IdentExpr (second)
Ok(Parsed::Incomplete), // CloseExpr
],
sut.by_ref().collect::<Vec<_>>(),
);
let asg = sut.finalize().unwrap().into_context();
// The identifier should continue to reference the first expression.
let expr = asg.expect_ident_obj::<Expr>(id_first);
assert_eq!(expr.span(), S1.merge(S3).unwrap());
// There's nothing we can do using the ASG's public API at the time of
// writing to try to reference the dangling expression.
// The second identifier should have been successfully bound despite the
// failed initial attempt.
let expr = asg.expect_ident_obj::<Expr>(id_second);
assert_eq!(expr.span(), S7.merge(S10).unwrap());
}
fn asg_from_toks<I: IntoIterator<Item = Air>>(toks: I) -> Asg
where
I::IntoIter: Debug,
{
let mut sut = Sut::parse(toks.into_iter());
assert!(sut.all(|x| x.is_ok()));
sut.finalize().unwrap().into_context()
}
fn collect_subexprs<O: ObjectKind>(
asg: &Asg,
oi: ObjectIndex<O>,
) -> Vec<(ObjectIndex<O>, &O)>
where
O: ObjectRelTo<O>,
{
oi.edges::<O>(&asg)
.map(|oi| (oi, oi.resolve(&asg)))
.collect::<Vec<_>>()
}