simplicity/node/
construct.rs

1// SPDX-License-Identifier: CC0-1.0
2
3use crate::dag::{InternalSharing, PostOrderIterItem};
4use crate::jet::Jet;
5use crate::types::{self, arrow::Arrow};
6use crate::{encode, BitIter, BitWriter, Cmr, FailEntropy, FinalizeError, RedeemNode, Value, Word};
7
8use std::io;
9use std::marker::PhantomData;
10use std::sync::Arc;
11
12use super::{
13    Commit, CommitData, CommitNode, Converter, Inner, Marker, NoDisconnect, NoWitness, Node,
14    Redeem, RedeemData,
15};
16use super::{CoreConstructible, DisconnectConstructible, JetConstructible, WitnessConstructible};
17
18/// ID used to share [`ConstructNode`]s.
19///
20/// This is impossible to construct, which is a promise that it is impossible
21/// to share [`ConstructNode`]s.
22#[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Debug, Hash)]
23pub enum ConstructId {}
24
25#[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Debug, Hash)]
26pub struct Construct<J> {
27    /// Makes the type non-constructible.
28    never: std::convert::Infallible,
29    /// Required by Rust.
30    phantom: std::marker::PhantomData<J>,
31}
32
33impl<J: Jet> Marker for Construct<J> {
34    type CachedData = ConstructData<J>;
35    type Witness = Option<Value>;
36    type Disconnect = Option<Arc<ConstructNode<J>>>;
37    type SharingId = ConstructId;
38    type Jet = J;
39
40    fn compute_sharing_id(_: Cmr, _: &ConstructData<J>) -> Option<ConstructId> {
41        None
42    }
43}
44
45pub type ConstructNode<J> = Node<Construct<J>>;
46
47impl<J: Jet> ConstructNode<J> {
48    /// Accessor for the node's arrow
49    pub fn arrow(&self) -> &Arrow {
50        self.data.arrow()
51    }
52
53    /// Sets the source and target type of the node to unit
54    pub fn set_arrow_to_program(&self) -> Result<(), types::Error> {
55        let ctx = self.data.inference_context();
56        let unit_ty = types::Type::unit(ctx);
57        ctx.unify(
58            &self.arrow().source,
59            &unit_ty,
60            "setting root source to unit",
61        )?;
62        ctx.unify(
63            &self.arrow().target,
64            &unit_ty,
65            "setting root target to unit",
66        )?;
67        Ok(())
68    }
69
70    /// Convert a [`ConstructNode`] to a [`CommitNode`] by finalizing all of the types.
71    ///
72    /// Also sets the source and target type of this node to unit. This is almost
73    /// certainly what you want, since the resulting `CommitNode` cannot be further
74    /// composed, and needs to be 1->1 to go on-chain. But if you don't, call
75    /// [`Self::finalize_types_non_program`] instead.
76    pub fn finalize_types(&self) -> Result<Arc<CommitNode<J>>, types::Error> {
77        self.set_arrow_to_program()?;
78        self.finalize_types_non_program()
79    }
80
81    /// Convert a [`ConstructNode`] to a [`CommitNode`] by finalizing all of the types.
82    ///
83    /// Does *not* sets the source and target type of this node to unit.
84    pub fn finalize_types_non_program(&self) -> Result<Arc<CommitNode<J>>, types::Error> {
85        struct FinalizeTypes<J: Jet>(PhantomData<J>);
86
87        impl<J: Jet> Converter<Construct<J>, Commit<J>> for FinalizeTypes<J> {
88            type Error = types::Error;
89
90            fn convert_witness(
91                &mut self,
92                _: &PostOrderIterItem<&ConstructNode<J>>,
93                _: &Option<Value>,
94            ) -> Result<NoWitness, Self::Error> {
95                Ok(NoWitness)
96            }
97
98            fn convert_disconnect(
99                &mut self,
100                _: &PostOrderIterItem<&ConstructNode<J>>,
101                _: Option<&Arc<CommitNode<J>>>,
102                _: &Option<Arc<ConstructNode<J>>>,
103            ) -> Result<NoDisconnect, Self::Error> {
104                Ok(NoDisconnect)
105            }
106
107            fn convert_data(
108                &mut self,
109                data: &PostOrderIterItem<&ConstructNode<J>>,
110                inner: Inner<&Arc<CommitNode<J>>, J, &NoDisconnect, &NoWitness>,
111            ) -> Result<Arc<CommitData<J>>, Self::Error> {
112                let converted_data = inner.map(|node| node.cached_data());
113                CommitData::new(&data.node.data.arrow, converted_data).map(Arc::new)
114            }
115        }
116
117        self.convert::<InternalSharing, _, _>(&mut FinalizeTypes(PhantomData))
118    }
119
120    /// Finalize the witness program as an unpruned redeem program.
121    ///
122    /// Witness nodes must be populated with sufficient data,
123    /// to ensure that the resulting redeem program successfully runs on the Bit Machine.
124    /// Furthermore, **all** disconnected branches must be populated,
125    /// even those that are not executed.
126    ///
127    /// The resulting redeem program is **not pruned**.
128    ///
129    /// ## See
130    ///
131    /// [`RedeemNode::prune`]
132    pub fn finalize_unpruned(&self) -> Result<Arc<RedeemNode<J>>, FinalizeError> {
133        struct Finalizer<J>(PhantomData<J>);
134
135        impl<J: Jet> Converter<Construct<J>, Redeem<J>> for Finalizer<J> {
136            type Error = FinalizeError;
137
138            fn convert_witness(
139                &mut self,
140                data: &PostOrderIterItem<&ConstructNode<J>>,
141                wit: &Option<Value>,
142            ) -> Result<Value, Self::Error> {
143                if let Some(ref wit) = wit {
144                    Ok(wit.shallow_clone())
145                } else {
146                    // We insert a zero value into unpopulated witness nodes,
147                    // assuming that this node will later be pruned out of the program.
148                    //
149                    // Pruning requires running a program on the Bit Machine,
150                    // which in turn requires a program with fully populated witness nodes.
151                    // It would be horrible UX to force the caller to provide witness data
152                    // even for unexecuted branches, so we insert zero values here.
153                    //
154                    // If this node is executed after all, then the caller can fix the witness
155                    // data based on the returned execution error.
156                    //
157                    // Zero values may "accidentally" satisfy a program even if the caller
158                    // didn't provide any witness data. However, this is only the case for the
159                    // most trivial programs. The only place where we must be careful is our
160                    // unit tests, which tend to include these kinds of trivial programs.
161                    let ty = data
162                        .node
163                        .arrow()
164                        .target
165                        .finalize()
166                        .map_err(FinalizeError::Type)?;
167                    Ok(Value::zero(&ty))
168                }
169            }
170
171            fn convert_disconnect(
172                &mut self,
173                _: &PostOrderIterItem<&ConstructNode<J>>,
174                maybe_converted: Option<&Arc<RedeemNode<J>>>,
175                _: &Option<Arc<ConstructNode<J>>>,
176            ) -> Result<Arc<RedeemNode<J>>, Self::Error> {
177                if let Some(child) = maybe_converted {
178                    Ok(Arc::clone(child))
179                } else {
180                    Err(FinalizeError::DisconnectRedeemTime)
181                }
182            }
183
184            fn convert_data(
185                &mut self,
186                data: &PostOrderIterItem<&ConstructNode<J>>,
187                inner: Inner<&Arc<RedeemNode<J>>, J, &Arc<RedeemNode<J>>, &Value>,
188            ) -> Result<Arc<RedeemData<J>>, Self::Error> {
189                let converted_data = inner
190                    .map(|node| node.cached_data())
191                    .map_disconnect(|node| node.cached_data())
192                    .map_witness(Value::shallow_clone);
193                Ok(Arc::new(RedeemData::new(
194                    data.node.arrow().finalize().map_err(FinalizeError::Type)?,
195                    converted_data,
196                )))
197            }
198        }
199
200        self.convert::<InternalSharing, _, _>(&mut Finalizer(PhantomData))
201    }
202
203    /// Finalize the witness program as a pruned redeem program.
204    ///
205    /// Witness nodes must be populated with sufficient data,
206    /// to ensure that the resulting redeem program successfully runs on the Bit Machine.
207    /// Furthermore, **all** disconnected branches must be populated,
208    /// even those that are not executed.
209    ///
210    /// The resulting redeem program is **pruned** based on the given transaction environment.
211    ///
212    /// ## See
213    ///
214    /// [`RedeemNode::prune`]
215    pub fn finalize_pruned(
216        &self,
217        env: &J::Environment,
218    ) -> Result<Arc<RedeemNode<J>>, FinalizeError> {
219        let unpruned = self.finalize_unpruned()?;
220        unpruned.prune(env).map_err(FinalizeError::Execution)
221    }
222
223    /// Decode a Simplicity expression from bits, without witness data.
224    ///
225    /// # Usage
226    ///
227    /// Use this method only if the serialization **does not** include the witness data.
228    /// This means, the program simply has no witness during commitment,
229    /// or the witness is provided by other means.
230    ///
231    /// If the serialization contains the witness data, then use [`crate::RedeemNode::decode()`].
232    pub fn decode<I: Iterator<Item = u8>>(
233        mut bits: BitIter<I>,
234    ) -> Result<Arc<Self>, crate::decode::Error> {
235        let res = crate::decode::decode_expression(&mut bits)?;
236        bits.close()?;
237        Ok(res)
238    }
239
240    #[cfg(feature = "base64")]
241    #[allow(clippy::should_implement_trait)] // returns Arc<Self>
242    pub fn from_str(s: &str) -> Result<Arc<Self>, crate::ParseError> {
243        use crate::base64::engine::general_purpose;
244        use crate::base64::Engine as _;
245
246        let v = general_purpose::STANDARD
247            .decode(s)
248            .map_err(crate::ParseError::Base64)?;
249        let iter = crate::BitIter::new(v.into_iter());
250        Self::decode(iter)
251            .map_err(crate::DecodeError::Decode)
252            .map_err(crate::ParseError::Decode)
253    }
254
255    /// Encode a Simplicity expression to bits, with no witness data
256    #[deprecated(since = "0.5.0", note = "use Self::encode_without_witness instead")]
257    pub fn encode<W: io::Write>(&self, w: &mut BitWriter<W>) -> io::Result<usize> {
258        let program_bits = encode::encode_program(self, w)?;
259        w.flush_all()?;
260        Ok(program_bits)
261    }
262}
263
264#[derive(Clone, Debug)]
265pub struct ConstructData<J> {
266    arrow: Arrow,
267    /// This isn't really necessary, but it helps type inference if every
268    /// struct has a \<J\> parameter, since it forces the choice of jets to
269    /// be consistent without the user needing to specify it too many times.
270    phantom: PhantomData<J>,
271}
272
273impl<J: Jet> ConstructData<J> {
274    /// Constructs a new [`ConstructData`] from an (unfinalized) type arrow
275    pub fn new(arrow: Arrow) -> Self {
276        ConstructData {
277            arrow,
278            phantom: PhantomData,
279        }
280    }
281
282    /// Accessor for the node's arrow
283    pub fn arrow(&self) -> &Arrow {
284        &self.arrow
285    }
286}
287
288impl<J> CoreConstructible for ConstructData<J> {
289    fn iden(inference_context: &types::Context) -> Self {
290        ConstructData {
291            arrow: Arrow::iden(inference_context),
292            phantom: PhantomData,
293        }
294    }
295
296    fn unit(inference_context: &types::Context) -> Self {
297        ConstructData {
298            arrow: Arrow::unit(inference_context),
299            phantom: PhantomData,
300        }
301    }
302
303    fn injl(child: &Self) -> Self {
304        ConstructData {
305            arrow: Arrow::injl(&child.arrow),
306            phantom: PhantomData,
307        }
308    }
309
310    fn injr(child: &Self) -> Self {
311        ConstructData {
312            arrow: Arrow::injr(&child.arrow),
313            phantom: PhantomData,
314        }
315    }
316
317    fn take(child: &Self) -> Self {
318        ConstructData {
319            arrow: Arrow::take(&child.arrow),
320            phantom: PhantomData,
321        }
322    }
323
324    fn drop_(child: &Self) -> Self {
325        ConstructData {
326            arrow: Arrow::drop_(&child.arrow),
327            phantom: PhantomData,
328        }
329    }
330
331    fn comp(left: &Self, right: &Self) -> Result<Self, types::Error> {
332        Ok(ConstructData {
333            arrow: Arrow::comp(&left.arrow, &right.arrow)?,
334            phantom: PhantomData,
335        })
336    }
337
338    fn case(left: &Self, right: &Self) -> Result<Self, types::Error> {
339        Ok(ConstructData {
340            arrow: Arrow::case(&left.arrow, &right.arrow)?,
341            phantom: PhantomData,
342        })
343    }
344
345    fn assertl(left: &Self, right: Cmr) -> Result<Self, types::Error> {
346        Ok(ConstructData {
347            arrow: Arrow::assertl(&left.arrow, right)?,
348            phantom: PhantomData,
349        })
350    }
351
352    fn assertr(left: Cmr, right: &Self) -> Result<Self, types::Error> {
353        Ok(ConstructData {
354            arrow: Arrow::assertr(left, &right.arrow)?,
355            phantom: PhantomData,
356        })
357    }
358
359    fn pair(left: &Self, right: &Self) -> Result<Self, types::Error> {
360        Ok(ConstructData {
361            arrow: Arrow::pair(&left.arrow, &right.arrow)?,
362            phantom: PhantomData,
363        })
364    }
365
366    fn fail(inference_context: &types::Context, entropy: FailEntropy) -> Self {
367        ConstructData {
368            arrow: Arrow::fail(inference_context, entropy),
369            phantom: PhantomData,
370        }
371    }
372
373    fn const_word(inference_context: &types::Context, word: Word) -> Self {
374        ConstructData {
375            arrow: Arrow::const_word(inference_context, word),
376            phantom: PhantomData,
377        }
378    }
379
380    fn inference_context(&self) -> &types::Context {
381        self.arrow.inference_context()
382    }
383}
384
385impl<J: Jet> DisconnectConstructible<Option<Arc<ConstructNode<J>>>> for ConstructData<J> {
386    fn disconnect(
387        left: &Self,
388        right: &Option<Arc<ConstructNode<J>>>,
389    ) -> Result<Self, types::Error> {
390        let right = right.as_ref();
391        Ok(ConstructData {
392            arrow: Arrow::disconnect(&left.arrow, &right.map(|n| n.arrow()))?,
393            phantom: PhantomData,
394        })
395    }
396}
397
398impl<J> WitnessConstructible<Option<Value>> for ConstructData<J> {
399    fn witness(inference_context: &types::Context, _witness: Option<Value>) -> Self {
400        ConstructData {
401            arrow: Arrow::witness(inference_context, NoWitness),
402            phantom: PhantomData,
403        }
404    }
405}
406
407impl<J: Jet> JetConstructible<J> for ConstructData<J> {
408    fn jet(inference_context: &types::Context, jet: J) -> Self {
409        ConstructData {
410            arrow: Arrow::jet(inference_context, jet),
411            phantom: PhantomData,
412        }
413    }
414}
415
416#[cfg(test)]
417mod tests {
418    use super::*;
419    use crate::jet::Core;
420    use crate::types::Final;
421    use crate::Value;
422
423    #[test]
424    fn occurs_check_error() {
425        let ctx = types::Context::new();
426        let iden = Arc::<ConstructNode<Core>>::iden(&ctx);
427        let node = Arc::<ConstructNode<Core>>::disconnect(&iden, &Some(Arc::clone(&iden))).unwrap();
428
429        assert!(matches!(
430            node.finalize_types_non_program(),
431            Err(types::Error::OccursCheck { .. }),
432        ));
433    }
434
435    #[test]
436    fn occurs_check_2() {
437        let ctx = types::Context::new();
438        // A more complicated occurs-check test that caused a deadlock in the past.
439        let iden = Arc::<ConstructNode<Core>>::iden(&ctx);
440        let injr = Arc::<ConstructNode<Core>>::injr(&iden);
441        let pair = Arc::<ConstructNode<Core>>::pair(&injr, &iden).unwrap();
442        let drop = Arc::<ConstructNode<Core>>::drop_(&pair);
443
444        let case1 = Arc::<ConstructNode<Core>>::case(&drop, &drop).unwrap();
445        let case2 = Arc::<ConstructNode<Core>>::case(&case1, &case1).unwrap();
446
447        let comp1 = Arc::<ConstructNode<Core>>::comp(&case2, &case2).unwrap();
448        let comp2 = Arc::<ConstructNode<Core>>::comp(&comp1, &case1).unwrap();
449
450        assert!(matches!(
451            comp2.finalize_types_non_program(),
452            Err(types::Error::OccursCheck { .. }),
453        ));
454    }
455
456    #[test]
457    fn occurs_check_3() {
458        let ctx = types::Context::new();
459        // A similar example that caused a slightly different deadlock in the past.
460        let wit = Arc::<ConstructNode<Core>>::witness(&ctx, None);
461        let drop = Arc::<ConstructNode<Core>>::drop_(&wit);
462
463        let comp1 = Arc::<ConstructNode<Core>>::comp(&drop, &drop).unwrap();
464        let comp2 = Arc::<ConstructNode<Core>>::comp(&comp1, &comp1).unwrap();
465        let comp3 = Arc::<ConstructNode<Core>>::comp(&comp2, &comp2).unwrap();
466        let comp4 = Arc::<ConstructNode<Core>>::comp(&comp3, &comp3).unwrap();
467        let comp5 = Arc::<ConstructNode<Core>>::comp(&comp4, &comp4).unwrap();
468
469        let case = Arc::<ConstructNode<Core>>::case(&comp5, &comp4).unwrap();
470        let drop2 = Arc::<ConstructNode<Core>>::drop_(&case);
471        let case2 = Arc::<ConstructNode<Core>>::case(&drop2, &case).unwrap();
472        let comp6 = Arc::<ConstructNode<Core>>::comp(&case2, &case2).unwrap();
473        let case3 = Arc::<ConstructNode<Core>>::case(&comp6, &comp6).unwrap();
474
475        let comp7 = Arc::<ConstructNode<Core>>::comp(&case3, &case3).unwrap();
476        let comp8 = Arc::<ConstructNode<Core>>::comp(&comp7, &comp7).unwrap();
477
478        assert!(matches!(
479            comp8.finalize_types_non_program(),
480            Err(types::Error::OccursCheck { .. }),
481        ));
482    }
483
484    #[test]
485    fn type_check_error() {
486        let ctx = types::Context::new();
487        let unit = Arc::<ConstructNode<Core>>::unit(&ctx);
488        let case = Arc::<ConstructNode<Core>>::case(&unit, &unit).unwrap();
489
490        assert!(matches!(
491            Arc::<ConstructNode<Core>>::disconnect(&case, &Some(unit)),
492            Err(types::Error::Bind { .. }),
493        ));
494    }
495
496    #[test]
497    fn scribe() {
498        // Ok to use same type inference context for all the below tests,
499        // since everything has concrete types and anyway we only care
500        // about CMRs, for which type inference is irrelevant.
501        let ctx = types::Context::new();
502        let unit = Arc::<ConstructNode<Core>>::unit(&ctx);
503        let bit0 = Arc::<ConstructNode<Core>>::const_word(&ctx, Word::u1(0));
504        let bit1 = Arc::<ConstructNode<Core>>::const_word(&ctx, Word::u1(1));
505
506        assert_eq!(
507            unit.cmr(),
508            Arc::<ConstructNode<Core>>::scribe(&ctx, &Value::unit()).cmr()
509        );
510        assert_eq!(
511            bit0.cmr(),
512            Arc::<ConstructNode<Core>>::scribe(&ctx, &Value::u1(0)).cmr()
513        );
514        assert_eq!(
515            bit1.cmr(),
516            Arc::<ConstructNode<Core>>::scribe(&ctx, &Value::u1(1)).cmr()
517        );
518        assert_eq!(
519            Arc::<ConstructNode<Core>>::const_word(&ctx, Word::u2(1)).cmr(),
520            Arc::<ConstructNode<Core>>::scribe(&ctx, &Value::u2(1)).cmr()
521        );
522        assert_eq!(
523            Arc::<ConstructNode<Core>>::injl(&bit0).cmr(),
524            Arc::<ConstructNode<Core>>::scribe(&ctx, &Value::left(Value::u1(0), Final::unit()))
525                .cmr()
526        );
527        assert_eq!(
528            Arc::<ConstructNode<Core>>::injr(&bit1).cmr(),
529            Arc::<ConstructNode<Core>>::scribe(&ctx, &Value::right(Final::unit(), Value::u1(1)))
530                .cmr()
531        );
532        assert_eq!(
533            Arc::<ConstructNode<Core>>::pair(&unit, &unit)
534                .unwrap()
535                .cmr(),
536            Arc::<ConstructNode<Core>>::scribe(&ctx, &Value::product(Value::unit(), Value::unit()))
537                .cmr()
538        );
539    }
540
541    #[test]
542    fn regression_286_1() {
543        // This is the smallest pure Simplicity program I was able to find that exhibits the bad
544        // behavior seen in https://github.com/BlockstreamResearch/rust-simplicity/issues/286
545        let ctx = types::Context::new();
546        let cmr = Cmr::from_byte_array([0xde; 32]);
547
548        let u0 = Arc::<ConstructNode<Core>>::unit(&ctx);
549        let i1 = Arc::<ConstructNode<Core>>::injl(&u0);
550        let i2 = Arc::<ConstructNode<Core>>::injr(&i1);
551        let i3 = Arc::<ConstructNode<Core>>::injr(&i2);
552        let i4 = Arc::<ConstructNode<Core>>::injl(&i3);
553        let u5 = Arc::<ConstructNode<Core>>::unit(&ctx);
554        let i6 = Arc::<ConstructNode<Core>>::injl(&u5);
555        let i7 = Arc::<ConstructNode<Core>>::injr(&i6);
556        let p8 = Arc::<ConstructNode<Core>>::pair(&i4, &i7).unwrap();
557        let u9 = Arc::<ConstructNode<Core>>::unit(&ctx);
558        let a10 = Arc::<ConstructNode<Core>>::assertr(cmr, &u9).unwrap();
559        let u11 = Arc::<ConstructNode<Core>>::unit(&ctx);
560        let a12 = Arc::<ConstructNode<Core>>::assertr(cmr, &u11).unwrap();
561        let a13 = Arc::<ConstructNode<Core>>::assertl(&a12, cmr).unwrap();
562        let c14 = Arc::<ConstructNode<Core>>::case(&a10, &a13).unwrap();
563        let c15 = Arc::<ConstructNode<Core>>::comp(&p8, &c14).unwrap();
564
565        let finalized: Arc<CommitNode<_>> = c15.finalize_types().unwrap();
566        let prog = finalized.to_vec_without_witness();
567        // In #286 we are encoding correctly...
568        assert_eq!(
569            hex::DisplayHex::as_hex(&prog).to_string(),
570            "dc920a28812b6f6f6f6f6f6f6f6f6f6f6f6f6f6f6f6f6f6f6f6f6f6f6f6f6f6f6f6f6f6f6f6f243090e00b10e00680",
571        );
572
573        let prog = BitIter::from(prog);
574        let decode = CommitNode::<Core>::decode(prog).unwrap();
575
576        // ...but then during decoding we read the program incorrectly and this assertion fails.
577        assert_eq!(finalized, decode);
578    }
579
580    #[test]
581    fn regression_286_2() {
582        // This one is smaller because it starts with a witness node which has a large type.
583        // This is a bit easier to grok but can't be serialized as a complete/valid program
584        // without providing the witness data, which limits its ability to share with the
585        // other libraries.
586        //
587        // It also exhibits the bug earlier than the other one -- it *should* just fail to
588        // typecheck and not be constructible. So we can't get an encoding of it.
589        let ctx = types::Context::new();
590
591        let w0 = Arc::<ConstructNode<Core>>::witness(&ctx, None);
592        let i1 = Arc::<ConstructNode<Core>>::iden(&ctx);
593        let d2 = Arc::<ConstructNode<Core>>::drop_(&i1);
594        let i3 = Arc::<ConstructNode<Core>>::iden(&ctx);
595        let i4 = Arc::<ConstructNode<Core>>::iden(&ctx);
596        let t5 = Arc::<ConstructNode<Core>>::take(&i4);
597        let ca6 = Arc::<ConstructNode<Core>>::case(&i3, &t5).unwrap();
598        let ca7 = Arc::<ConstructNode<Core>>::case(&d2, &ca6).unwrap();
599        let c8 = Arc::<ConstructNode<Core>>::comp(&w0, &ca7).unwrap();
600        let u9 = Arc::<ConstructNode<Core>>::unit(&ctx);
601        let c10 = Arc::<ConstructNode<Core>>::comp(&c8, &u9).unwrap();
602
603        // In #286 we incorrectly succeed finalizing the types, and then encode a bad program.
604        let err = c10.finalize_types().unwrap_err();
605        assert!(matches!(err, types::Error::OccursCheck { .. }));
606    }
607}
simplicity/node/construct.rs

simplicity/node/
construct.rs
