#36442 allows multipath descriptors to be represented in a single Descriptor object. GetMultipathExpansion returns the multiple descriptors represented by a multipath descriptor. This expansion is reversible - given the expansion in the order of the multipath elements, it is possible to determine what the original multipath descriptor was. This PR adds ReconstructMultipath to produce a new Descriptor representing the multipath descriptor that produced the expansion.
Depends on #36442
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| Concept ACK | w0xlt |
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Possible typos and grammar issues:
src/util/bip32.h: for a give multipath position → for a given multipath position [“give” is a typo]src/test/descriptor_tests.cpp: Failed reconstrcted to private string → Failed reconstructed to private string [“reconstrcted” is misspelled]Possible places where named args for integral literals may be used (e.g. func(x, /*named_arg=*/0) in C++, and func(x, named_arg=0) in Python):
src/scriptpubkeyman.cpp: Parse(desc_str, provider, error, false) (combo descriptor)src/scriptpubkeyman.cpp: Parse(desc_str, provider, error, false) (chain descriptor)src/scriptpubkeyman.cpp: WalletDescriptor w_desc(std::move(desc), creation_time, 0, 0, 0)src/scriptpubkeyman.cpp: WalletDescriptor w_desc(std::move(desc), 0, 0, chain_counter, 0)src/wallet/rpc/spend.cpp: Parse(desc_str, desc_out, error, true)src/wallet/test/fuzz/scriptpubkeyman.cpp: Parse(desc_str.value(), keys, error, false)src/wallet/test/util.cpp: Parse(desc_str, keys, error, false)src/wallet/walletutil.cpp: Parse(desc_str, keys, error, false)src/wallet/walletutil.cpp: WalletDescriptor w_desc(std::move(desc), creation_time, 0, 0, 0)<sup>2026-10-07 18:03:03</sup>
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🚧 At least one of the CI tasks failed.
<sub>Task macOS-cross to arm64: https://github.com/bitcoin/bitcoin/actions/runs/37381386585/job/112003972868</sub>
<sub>LLM reason (✨ experimental): CI failed to compile walletload_tests.cpp: Parse() returns a std::unique_ptr<Descriptor>, but the code assigns it to a vector of those pointers.</sub>
<details><summary>Hints</summary>
Try to run the tests locally, according to the documentation. However, a CI failure may still happen due to a number of reasons, for example:
Possibly due to a silent merge conflict (the changes in this pull request being incompatible with the current code in the target branch). If so, make sure to rebase on the latest commit of the target branch.
A sanitizer issue, which can only be found by compiling with the sanitizer and running the affected test.
An intermittent issue.
Leave a comment here, if you need help tracking down a confusing failure.
</details>
We will want to have member functions on KeyPath later, so make it a
class now.
Moves all of the multipath parsing into ParseHDKeypath, and let
KeyPathElement be a multipath element.
Internally, descriptor parsing will produce multipath descriptor objects
rather than std::vector<DescriptorImpl>. This single multipath
descriptor becomes std::vector<Descriptor> within Parse. Future commits
will return the single multipath descriptor object for all descriptor parsing.
Instead of a std::vector<std::unique_ptr<Descriptor>>, Parse can return
a single std::unique_ptr<Descriptor> that contains the multipath
information if the descriptor was multipath. Callers that
require the multipath expansion use GetMultipathExpansion() to get the
expanded descriptors.
Concept ACK