test: Descriptor roundtrip and raw()/ addr() coverage #36013

pull pablomartin4btc wants to merge 2 commits into bitcoin:master from pablomartin4btc:descriptor/roundtrip-raw-addr-tests changing 1 files +99 −6

pablomartin4btc commented at 7:29 PM on August 18, 2026: member
Part 1 of 2, reviving #24361.

<details> <summary>Ports the two test-only commits from the original PR above, re-applied against the current <code>descriptor_tests.cpp</code> — the original no longer applies cleanly, since <code>DoCheck()</code>'s signature has changed substantially since the original PR was created back in 2022.</summary> <br>

norm_prv was dropped, and op_desc_id, spender_nlocktime, spender_nsequence, preimages, expected_prv/expected_pub, and desc_index were all added - so the original diff no longer applies...
```
diff -u <(git show 15220ec903:src/test/descriptor_tests.cpp | sed -n '/^void DoCheck/,/^{/p') \
        <(git show HEAD:src/test/descriptor_tests.cpp | sed -n '/^void DoCheck/,/^{/p')
```
```
@@ -1,3 +1,7 @@
-void DoCheck(const std::string& prv, const std::string& pub, const std::string& norm_prv, const std::string& norm_pub, int flags, const std::vector<std::vector<std::string>>& scripts, const std::optional<OutputType>& type, const std::set<std::vector<uint32_t>>& paths = ONLY_EMPTY,
-    bool replace_apostrophe_with_h_in_prv=false, bool replace_apostrophe_with_h_in_pub=false)
+void DoCheck(std::string prv, std::string pub, const std::string& norm_pub, int flags,
+             const std::vector<std::vector<std::string>>& scripts, const std::optional<OutputType>& type, std::optional<uint256> op_desc_id = std::nullopt,
+             const std::set<std::vector<uint32_t>>& paths = ONLY_EMPTY, bool replace_apostrophe_with_h_in_prv=false,
+             bool replace_apostrophe_with_h_in_pub=false, uint32_t spender_nlocktime=0, uint32_t spender_nsequence=CTxIn::SEQUENCE_FINAL,
+             std::map<std::vector<uint8_t>, std::vector<uint8_t>> preimages={},
+             std::optional<std::string> expected_prv = std::nullopt, std::optional<std::string> expected_pub = std::nullopt, int desc_index = 0)
 {
 
```
</details>
- Roundtrip testing that inferring a descriptor from a generated scriptPubKey reproduces the original descriptor's structure (keys stripped from both sides for comparison). Added extension for MuSig key expressions (#31244) and BIP389 multipath (#22838), both added since 2022, and skipping for multi-branch taproot trees, where sibling order isn't meaningful. (For more details check 1st commit body)
- Check() coverage for valid raw() and addr() descriptors, previously exercised only for invalid inputs and only in the script-to-descriptor direction. Added a new NO_KEYS flag, since these descriptors have zero keys and several existing checks assumed at least one. (For more details check 2nd commit body)
No behavior change, test-only.

Part 2 (not yet opened): the ToString()/ToPrivateString() merge from #24361, independent of this PR — needs more design work before it's ready.

test: Roundtripping of descriptors ignoring keys

Add DropKeys(), which strips a descriptor string down to structure
only (key material replaced with "<KEY>", sortedmulti() normalized to
multi(), checksum dropped), and use it to check that inferring a
descriptor back from a script it generated reproduces the original
descriptor's structure.

A few descriptor features need special handling for this comparison
to hold:

- MuSig key expressions (musig(...)) aren't recognized by the plain
  key-matching regex. Added a separate pass collapsing musig()
  expressions (and any trailing derivation path) to <KEY> before the
  plain-key regex runs, rather than teaching that regex to understand
  musig()'s internals recursively.
- BIP389 multipath key expressions (<1;2;3>) in derivation paths.
  Extended the path-segment pattern to recognize them, which added
  two capture groups to the key-matching regex and shifted the
  position of the group the replacement substitutes back in.
  Computed that position from the regex's own capture count instead
  of hardcoding it, so it can't silently drift out of sync again.
- Sibling branches within a taproot script tree have no meaningful
  order (it's a Merkle tree), so InferDescriptor() reconstructing a
  multi-leaf tree in a different but equally valid branch order isn't
  something a plain string comparison can account for. Skipped the
  check for any taproot descriptor with more than one script leaf,
  detected via the presence of '{' in the descriptor string (the
  grammar only emits '{'/'}' for grouping 2+ branches).

Co-authored-by: Pieter Wuille <pieter@wuille.net>

d840df45ea

test: raw() and addr() descriptors in unit tests

Add Check() coverage for valid raw() and addr() descriptors: a raw
script, legacy and P2SH addresses, two bech32 v0 addresses, and two
future-witness-version addresses (v1 and v2, both expected
non-standard/unsolvable) - verifying checksum handling, solvability,
script derivation, and structural roundtripping. Address/script pairs
verified against a live node's own validateaddress before use.

These descriptors have no key expressions at all, which DoCheck()
didn't previously account for:

- keys_priv.keys is expected to be empty rather than non-empty, gated
  on a new NO_KEYS flag.
- GetMaxKeyExpr()/GetKeyCount() are expected to both report zero
  rather than the usual "highest index + 1 == count" relationship.
  Added the NO_KEYS-aware branch for it.
- HavePrivateKeys() returns false for a keyless descriptor, not
  vacuously true - it didn't exist when the original patch was
  written, so this wasn't previously exercised. Gated
  have_all_private_keys on NO_KEYS in addition to the existing
  MISSING_PRIVKEYS.
- raw()/addr() hardcode ToPrivateString() to always fail, so the
  existing "can serialize back to the private version" check needs
  skipping for these descriptors too. Extended its MISSING_PRIVKEYS
  gate to also cover NO_KEYS.

Co-authored-by: Pieter Wuille <pieter@wuille.net>

5b4c861a60

DrahtBot added the label Tests on Aug 18, 2026
DrahtBot commented at 7:30 PM on August 18, 2026: contributor



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For details see: https://corecheck.dev/bitcoin/bitcoin/pulls/36013.



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w0xlt commented at 9:17 PM on August 18, 2026: contributor

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#22838 descriptors: Be able to specify change and receiving in a single descriptor string #24361 Descriptor unit tests and simplifications #31244 descriptors: MuSig2

test: Descriptor roundtrip and raw()/ addr() coverage #36013

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