rpc: Use self.Arg<_>(name) helper over manual and duplicate parsing #36384

maflcko commented at 8:05 PM on September 29, 2026: member

The Arg() helper has many benefits:

It does not require manual isNull checks
It does not require hard-coding the fallback/default value a second time
It does not require manually specifying the getter for the type. Specifying the type is enough.

So use it more broadly.

DrahtBot added the label RPC/REST/ZMQ on Sep 29, 2026

DrahtBot commented at 8:05 PM on September 29, 2026: contributor

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Code Coverage & Benchmarks

For details see: https://corecheck.dev/bitcoin/bitcoin/pulls/36384.

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Concept ACK	fanquake

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Conflicts

Reviewers, this pull request conflicts with the following ones:

#36264 (wallet rpc: fix stale argument metadata and help text by MrHodlX)
#35370 (rpc: add key-origin modes to PSBT processing RPCs by junbyjun1238)
#33112 (wallet: relax external_signer flag constraints by Sjors)
#32857 (wallet: allow skipping script paths by Sjors)
#32468 (rpc: generateblock to allow multiple outputs by polespinasa)

If you consider this pull request important, please also help to review the conflicting pull requests. Ideally, start with the one that should be merged first.

maflcko force-pushed on Sep 29, 2026

DrahtBot added the label CI failed on Sep 29, 2026

DrahtBot commented at 8:28 PM on September 29, 2026: contributor

🚧 At least one of the CI tasks failed. <sub>Task iwyu: https://github.com/bitcoin/bitcoin/actions/runs/36623882963/job/109595800670</sub> <sub>LLM reason (✨ experimental): CI failed because IWYU detected incorrect/missing includes and triggered a “Failure generated from IWYU” (returned exit code 1).</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>

rpc: Use the first arg name in GetParamIndex

GetName does not support aliases at all. However, it should be fine for
GetParamIndex (used in Arg and MaybeArg) to support lookup by the first
name.

The test is modified to show the second legacy alias is ignored.

fae108b0a2

maflcko force-pushed on Sep 29, 2026

rpc: doc: Use proper RPCArg::Default in verifychain faf064078b

maflcko force-pushed on Sep 30, 2026

refactor: rpc: Use self.Arg<_>(name) helper over manual isNull() ? fallback : getter()

The Arg() helper has many benefits:

* It does not require manual isNull checks
* It does not require hard-coding the fallback/default value a second time
* It does not require manually specifying the getter for the type. Specifying the type is enough.

So use it in this refactor, which does not change any behavior.

fae633e268

doc: Fix typo in walletcreatefundedpsbt dev comment

Use same wording as in walletprocesspsbt

fa77e12603

maflcko force-pushed on Sep 30, 2026

DrahtBot removed the label CI failed on Sep 30, 2026

fanquake commented at 9:23 AM on October 1, 2026: member

Concept ACK

maflcko commented at 9:39 AM on October 1, 2026: member

Forgot to say that everything here is a refactor, except for the cleanup commit that changes the schema of one RPC:

diff --git a/getopenrpcinfo.full.json b/getopenrpcinfo.full.json
index e0cebef..cbbf785 100644
--- a/getopenrpcinfo.full.json
+++ b/getopenrpcinfo.full.json
@@ -15035,5 +15035,5 @@
                         "type": "number",
-                        "x-bitcoin-default-hint": "3, range=0-4"
+                        "default": 3
                     },
-                    "description": "How thorough the block verification is:\n- level 0 reads the blocks from disk\n- level 1 verifies block validity\n- level 2 verifies undo data\n- level 3 checks disconnection of tip blocks\n- level 4 tries to reconnect the blocks\n- each level includes the checks of the previous levels"
+                    "description": "How thorough the block verification is (range 0-4):\n- level 0 reads the blocks from disk\n- level 1 verifies block validity\n- level 2 verifies undo data\n- level 3 checks disconnection of tip blocks\n- level 4 tries to reconnect the blocks\n- each level includes the checks of the previous levels"
                 },
@@ -15044,5 +15044,5 @@
                         "type": "number",
-                        "x-bitcoin-default-hint": "6, 0=all"
+                        "default": 6
                     },
-                    "description": "The number of blocks to check."
+                    "description": "The number of blocks to check (0=all)."
                 }
diff --git a/verifychain b/verifychain
index b742f17..1863a80 100644
--- a/verifychain
+++ b/verifychain
@@ -5,3 +5,3 @@ Verifies blockchain database.
 Arguments:
-1. checklevel    (numeric, optional, default=3, range=0-4) How thorough the block verification is:
+1. checklevel    (numeric, optional, default=3) How thorough the block verification is (range 0-4):
                  - level 0 reads the blocks from disk
@@ -12,3 +12,3 @@ Arguments:
                  - each level includes the checks of the previous levels
-2. nblocks       (numeric, optional, default=6, 0=all) The number of blocks to check.
+2. nblocks       (numeric, optional, default=6) The number of blocks to check (0=all).