test: Fix list index out of range error in feature_bip68_sequence.py #32765

1. 
   zaidmstrr commented at 4:09 pm on June 17, 2025: contributor

   Fixes #32334

   The test feature_bip68_sequence.py fails with IndexError: list index out of range error due to a mismatch between the number of inputs requested (at random) and the number of UTXOs available. The error is reproducible with the randomseed:

   0$ ./build/test/functional/feature_bip68_sequence.py --randomseed 6169832640268785903 
   

   This PR adds a valid upper bound to randomly select the inputs.

2. test: Fix list index out of range error in feature_bip68_sequence.py e285e691b7
3. 
   DrahtBot commented at 4:09 pm on June 17, 2025: contributor

   The following sections might be updated with supplementary metadata relevant to reviewers and maintainers.

   Code Coverage & Benchmarks

   For details see: https://corecheck.dev/bitcoin/bitcoin/pulls/32765.

   Reviews

   See the guideline for information on the review process.

   Type	Reviewers
   ACK	maflcko, Prabhat1308, theStack

   If your review is incorrectly listed, please react with 👎 to this comment and the bot will ignore it on the next update.

4. DrahtBot added the label Tests on Jun 17, 2025
5. 
   Prabhat1308 commented at 5:46 pm on June 17, 2025: contributor

   Approach ACK

   The tests passes even with the original suggestion from the issue here , I wonder why you did not go with that ?

   Although I see no issues with the current approach

   UPD: The test did run noticably slower with the original suggestion

6. in test/functional/feature_bip68_sequence.py:149 in e285e691b7

   143@@ -144,8 +144,10 @@ def test_sequence_lock_confirmed_inputs(self):
   144         # between height/time locking). Small random chance of making the locks
   145         # all pass.
   146         for _ in range(400):
   147+            available_utxos = len(utxos)
   148+
   149             # Randomly choose up to 10 inputs
   

   ---

   ---

   

   Prabhat1308 commented at 5:50 pm on June 17, 2025:

   This comment should be changed along the line “randomly choose upto minimum of 10 and available_utxo inputs here " now since its also bounded by the size of available_utxos

   Technically the statement still stands so no need to change

   ---

   

   zaidmstrr commented at 6:01 pm on June 17, 2025:

   Yes, still the maximum bound is 10.
7. 
   zaidmstrr commented at 6:12 pm on June 17, 2025: contributor

   The tests passes even with the original suggestion from the issue here , I wonder why you did not go with that ?

   The approach suggested here is resource inefficient compared to this. You need to create 4000 UTXOs which is 20x more than the current implementation.

8. 
   maflcko commented at 6:41 pm on June 17, 2025: member

   lgtm ACK e285e691b7a311e278f89e9fe423716de1ee268b
9. DrahtBot requested review from Prabhat1308 on Jun 17, 2025
10. 
    Prabhat1308 commented at 9:25 am on June 18, 2025: contributor

    re-ACK e285e69
11. theStack approved
12. 
    theStack commented at 10:44 pm on June 18, 2025: contributor

    ACK e285e691b7a311e278f89e9fe423716de1ee268b

    Thanks for fixing!

13. fanquake merged this on Jun 19, 2025
14. fanquake closed this on Jun 19, 2025

    ---

15. fanquake referenced this in commit 4c7ed36c96 on Jun 19, 2025
16. 
    fanquake commented at 2:07 pm on June 19, 2025: member

    Backported to 29.x in #32589.
17. fanquake referenced this in commit 983b268768 on Jun 25, 2025
18. fanquake referenced this in commit d235d5b77d on Jun 25, 2025
19. fanquake referenced this in commit 3c56d36bec on Jul 3, 2025
20. 
    fanquake commented at 4:37 pm on July 3, 2025: member

    Backported to 28.x in #32811.

Contributors
zaidmstrr DrahtBot Prabhat1308 maflcko theStack fanquake

Review Requested
Prabhat1308

Labels
Tests