29eafd5733 rpc: doc: use "output script" terminology consistently in "asm"/"hex" results (Sebastian Falbesoner)
Pull request description:
The wording "public key script" was likely chosen as a human-readable form of the technical term `scriptPubKey`, but it doesn't seem to be really widespread. Replace it by the more (probably most?) common term "output script" instead. Note that the argument for the `decodescript` RPC is not necessarily an output script (it could e.g. be also a redeem script), so in this case we just stay generic and use "script".
See also the draft BIP "Terminology for Transaction Components" (https://github.com/murchandamus/bips/blob/2022-04-tx-terminology/bip-tx-terminology.mediawiki) from murchandamus which suggests to use "output script" as well.
Affects the help text of the following RPCs:
- decodepsbt
- decoderawtransaction
- decodescript
- getblock (if verbosity=3)
- getrawtransaction (if verbosity=2,3)
- gettxout
ACKs for top commit:
maflcko:
ACK 29eafd5733
achow101:
ACK 29eafd5733
BrandonOdiwuor:
ACK 29eafd5733
tdb3:
ACK 29eafd5733
Tree-SHA512: 62eb92d42bc44e36dc3090df7b248a123868a74af253d2046de02086e688bf6ff98307b927ba2fee3d599f85e073aeb8eca90ed15105ca63b648b6796cfa340b
c504b6997b refactor: add coinbase constraints to BlockCreateOptions (Sjors Provoost)
6b4c817d4b refactor: pass BlockCreateOptions to createNewBlock (Sjors Provoost)
323cfed595 refactor: use CHECK_NONFATAL to avoid single-use symbol (Sjors Provoost)
Pull request description:
When generating a block template through e.g. getblocktemplate RPC, we reserve 4000 weight units and 400 sigops. Pools use this space for their coinbase outputs.
At least one pool patched their Bitcoin Core node to adjust these hardcoded values. They eventually [produced an invalid block](https://bitcoin.stackexchange.com/questions/117837/how-many-sigops-are-in-the-invalid-block-783426) which exceeded the sigops limit.
The existince of such patches suggests it may be useful to make this value configurable. This PR would make such a change easier. However, the main motivation is that in the Stratum v2 spec requires the pool to communicate the maximum bytes they intend
to add to the coinbase outputs.
Specifically the `CoinbaseOutputDataSize` message which is part of the [Template Distribution Protocol](https://github.com/stratum-mining/sv2-spec/blob/main/07-Template-Distribution-Protocol.md#71-coinbaseoutputdatasize-client---server) has a field `coinbase_output_max_additional_size`.
A proposed change to the spec adds the max additional sigops as well: https://github.com/stratum-mining/sv2-spec/pull/86. Whether that change makes it into the spec is not important though, as adding both to `BlockAssembler::Options` makes sense.
The first commit is a test refactor followup for #30335, related to the code that's changed here, but not required.
The second commit introduces BlockCreateOptions, with just `use_mempool`.
The thirds commit adds `coinbase_max_additional_weight` and `coinbase_output_max_additional_sigops` to `BlockCreateOptions`. They use the originally hardcoded values, and no existing caller overrides these defaults. This changes in #29432.
ACKs for top commit:
itornaza:
tested ACK c504b6997b
ryanofsky:
Code review ACK c504b6997b
ismaelsadeeq:
Code review ACK c504b6997b
Tree-SHA512: de2fa085f47048c91d95524e03f909f6f27f175c1fefa3d6106445e7eb5cf5b710eda6ea5b641cf3b4704a4e4e0181a0c829003b9fd35465f2a46167e5d64487
734076c6de [wallet, rpc]: add `max_tx_weight` to tx funding options (ismaelsadeeq)
b6fc5043c1 [wallet]: update the data type of `change_output_size`, `change_spend_size` and `tx_noinputs_size` to `int` (ismaelsadeeq)
baab0d2d43 [doc]: update reason for deducting change output weight (ismaelsadeeq)
7f61d31a5c [refactor]: update coin selection algorithms input parameter `max_weight` name (ismaelsadeeq)
Pull request description:
This PR taken over from #29264
The PR added an option `max_tx_weight` to transaction funding RPC's that ensures the resulting transaction weight does not exceed the specified `max_tx_weight` limit.
If `max_tx_weight` is not given `MAX_STANDARD_TX_WEIGHT` is used as the max threshold.
This PR addressed outstanding review comments in #29264
For more context and rationale behind this PR see https://delvingbitcoin.org/t/lightning-transactions-with-v3-and-ephemeral-anchors/418/11?u=instagibbs
ACKs for top commit:
achow101:
ACK 734076c6de
furszy:
utACK 734076c6de
rkrux:
reACK [734076c](734076c6de)
Tree-SHA512: 013501aa443d239ee2ac01bccfc5296490c27b4edebe5cfca6b96c842375e895e5cfeb5424e82e359be581460f8be92095855763a62779a18ccd5bdfdd7ddce7
fa6270737e rpc: Use CHECK_NONFATAL over Assert (MarcoFalke)
Pull request description:
Any RPC method should not abort the whole node when an internal logic error happens.
Fix it by just aborting this single RPC method call when an error happens.
Also, fix the linter to find the fixed cases.
ACKs for top commit:
achow101:
ACK fa6270737e
stickies-v:
ACK fa6270737e
tdb3:
ACK fa6270737e
hodlinator:
ACK fa6270737e
Tree-SHA512: dad2f31b01a66578949009499e4385fb4d72f0f897419f2a6e0ea02e799b9a31e6ecb5a67fa5d27fcbc7939fe8acd62dc04e877b35831493b7f2c604dec7dc64
Rather than pass options individually to createNewBlock and then
combining them into BlockAssembler::Options, this commit introduces
BlockCreateOptions and passes that instead.
Currently there's only one option (use_mempool) but the next
commit adds more.
Co-authored-by: Ryan Ofsky <ryan@ofsky.org>
3333bae9b2 tidy: modernize-use-equals-default (MarcoFalke)
Pull request description:
Prior to C++20, `modernize-use-equals-default` could have been problematic because it could turn a non-aggregate into an aggregate. The risk would be that aggregate initialization would be enabled where the author did not intend to enable it.
With C++20, aggregate for those is forbidden either way. (https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1008r1.pdf)
So enabled it for code clarity, consistency, and possibly unlocking compiler optimizations. See https://clang.llvm.org/extra/clang-tidy/checks/modernize/use-equals-default.html
ACKs for top commit:
stickies-v:
ACK 3333bae9b2
Tree-SHA512: ab42ff01be7ca7e7d8b4c6a485e68426f59627d83dd827cf292304829562348dc17a52ee009f5f6f3c1c2081d7166ffac4baef23197ebeba8de7767c6ddfe255
8789dc8f31 doc: Add note to getblockfrompeer on missing undo data (Fabian Jahr)
4a1975008b rpc: Make pruneheight also reflect undo data presence (Fabian Jahr)
96b4facc91 refactor, blockstorage: Generalize GetFirstStoredBlock (Fabian Jahr)
Pull request description:
The function `GetFirstStoredBlock()` helps us find the first block for which we have data. So far this function only looked for a block with `BLOCK_HAVE_DATA`. However, this doesn't mean that we also have the undo data of that block, and undo data might be required for what a user would like to do with those blocks. One example of how this might happen is if some blocks were fetched using the `getblockfrompeer` RPC. Blocks fetched from a peer will have data but no undo data.
The first commit here allows `GetFirstStoredBlock()` to check for undo data as well by passing a parameter. This alone is useful for #29553 and I would use it there.
In the second commit I am applying the undo check to the RPCs that report `pruneheight` to the user. I find this much more intuitive because I think the user expects to be able to do all operations on blocks up until the `pruneheight` but that is not the case if undo data is missing. I personally ran into this once before and now again when testing for assumeutxo when I had used `getblockfrompeer`. The following commit adds test coverage for this change of behavior.
The last commit adds a note in the docs of `getblockfrompeer` that undo data will not be available.
ACKs for top commit:
achow101:
ACK 8789dc8f31
furszy:
Code review ACK 8789dc8f31.
stickies-v:
ACK 8789dc8f31
Tree-SHA512: 90ae8bdd07a496ade579aa25240609c61c9ed173ad38d30533f6c631fe674e5a41727478ade69ca4b71a571ad94c9da4b33ebba6b5d8821109313c2de3bdfb3d
6ecda04fef random: drop ad-hoc Shuffle in favor of std::shuffle (Pieter Wuille)
da28a26aae bench random: benchmark more functions, and add InsecureRandomContext (Pieter Wuille)
0a9bbc64c1 random bench refactor: move to new bench/random.cpp (Pieter Wuille)
Pull request description:
This adds benchmarks for various operations on `FastRandomContext` and `InsecureRandomContext`, and then removes the ad-hoc `Shuffle` functions, now that it appears that standard library `std::shuffle` has comparable performance. The other reason for keeping `Shuffle`, namely the fact that libstdc++ used self-move (which debug mode panics on) has been fixed as well (see https://github.com/bitcoin/bitcoin/pull/29625#discussion_r1658344049).
ACKs for top commit:
achow101:
ACK 6ecda04fef
hodlinator:
ACK 6ecda04fef
dergoegge:
Code review ACK 6ecda04fef
Tree-SHA512: 2560b7312410581ff2b9bd0716e0f1558d910b5eadb9544785c972384985ac0f11f72d6b2797cfe2e7eb71fa57c30cffd98cc009cb4ee87a18b1524694211417
The wording "public key script" was likely chosen as a human-readable form of
the technical term `scriptPubKey`, but it doesn't seem to be really widespread.
Replace it by the more common term "output script" instead. Note that the
argument for the `decodescript` RPC is not necessarily an output script (it
could e.g. be also a redeem script), so in this case we just stay generic and
use "script".
See also the draft BIP "Terminology for Transaction Components"
(https://github.com/murchandamus/bips/blob/2022-04-tx-terminology/bip-tx-terminology.mediawiki)
which suggests to use "output script" as well.
Affects the help text of the following RPCs:
- decodepsbt
- decoderawtransaction
- decodescript
- getblock (if verbosity=3)
- getrawtransaction (if verbosity=2,3)
- gettxout
2342b46c45 test: Add coverage for getchaintxstats in assumeutxo context (Fabian Jahr)
faf2a6750b rpc: Reorder getchaintxstats output (MarcoFalke)
fa2dada0c9 rpc: Avoid getchaintxstats invalid results (MarcoFalke)
Pull request description:
The `getchaintxstats` RPC reply during AU background download may return non-zero, but invalid, values for `window_tx_count` and `txrate`.
For example, `txcount` may be zero for a to-be-downloaded block, but may be non-zero for an ancestor block which is already downloaded. Thus, the values returned may be negative (and cause intermediate integer sanitizer violations).
Also, `txcount` may be accurate for the snapshot base block, or a descendant of it. However it may be zero for an ancestor block that still needs to be downloaded. Thus, the values returned may be positive, but wrong.
Fix all issues by skipping the returned value if either `txcount` is unset (equal to zero).
Also, skip `txcount` in the returned value, if it is unset (equal to zero).
Fixes https://github.com/bitcoin/bitcoin/issues/29328
ACKs for top commit:
fjahr:
re-ACK 2342b46c45
achow101:
ACK 2342b46c45
mzumsande:
ACK 2342b46c45
Tree-SHA512: 931cecc40ee5dc0f96be728db7eb297155f8343076cd29c8b8c050c99fd1d568b80f54c9459a34ca7a9489c2474c729796d00eeb1934d6a9f7b4d6a53e3ec430
2f9bde69f4 test: Remove unnecessary restart in assumeutxo test (Fabian Jahr)
19ce3d407e assumeutxo: Check snapshot base block is not marked invalid (Fabian Jahr)
80315c0118 refactor: Move early loadtxoutset checks into ActiveSnapshot (Fabian Jahr)
Pull request description:
This was discovered in a discussion in #29996
If the base block of the snapshot is marked invalid or part of an invalid chain, we currently still load the snapshot and get stuck in a weird state where we have the snapshot chainstate but it will never connect to our valid chain.
While this scenario is highly unlikely to occur on mainnet, it still seems good to prevent this inconsistent state.
The behavior change described above is in the second commit.
The first commit refactors the early checks in the `loadtxoutset` RPC by moving them into `ActivateSnapshot()` in order to have the chance to cover them by unit tests in the future and have a more consistent interface. Previously checks were spread out between `rpc/blockchain.cpp` and `validation.cpp`. In order to be able to return the error message to users of the RPC, the return type of `ActivateSnapshot()` is changed from `bool` to `util::Result`.
The third commit removes an unnecessary restart introduced in #29428.
ACKs for top commit:
mzumsande:
re-ACK 2f9bde6
alfonsoromanz:
Re-ACK 2f9bde69f4. The RPC code looks much cleaner after the refactor. Also, it seems very useful to get the error message in the RPC response rather than having to rely on the logs in some scenarios if you are an RPC user.
achow101:
ACK 2f9bde69f4
Tree-SHA512: 5328dd88c3c7be3f1be97c9eef52ac3666c27188c30a798b3e949f3ffcb83be075127c107e4046f7f39f961a79911ea3d61b61f3c11e451b3e4c541c264eeed4
f1478c0545 mempool: move LoadMempool/DumpMempool to node (Cory Fields)
6d242ff1e9 kernel: remove mempool_persist.cpp (Cory Fields)
Pull request description:
DumpMempool/LoadMempool are not necessary for the kernel.
Noticed while working on instantiated logging.
I suppose these could have been left in on purpose, but I'm assuming it was probably just an oversight.
ACKs for top commit:
TheCharlatan:
Re-ACK f1478c0545
glozow:
ACK f1478c0545
stickies-v:
ACK f1478c0545
Tree-SHA512: 5825da0cf2e67470524eb6ebe397eb90755a368469a25f184df99ab935b3eb6d89eb802b41a6c3661e869bba3bbfa8ba9d95281bc75ebbf790ec5d9d1f79c66f
a74b0f93ef Have testBlockValidity hold cs_main instead of caller (Sjors Provoost)
f6dc6db44d refactor: use CHECK_NONFATAL to avoid single-use symbol (Sjors Provoost)
5fb2b70489 Drop unneeded lock from createNewBlock (Sjors Provoost)
75ce7637ad refactor: testBlockValidity make out argument last (Sjors Provoost)
83a9bef0e2 Add missing include for mining interface (Sjors Provoost)
Pull request description:
Followups from #30200
Fixes:
- `std::unique_ptr` needs `#include <memory>` (noticed while working on #30332, which has fewer includes than its parent PR that I originally tested with)
- Drop lock from createNewBlock that was spuriously added
- Have testBlockValidity hold cs_main instead of caller (also fixes a race condition in test-only code)
Refactor:
- Use CHECK_NONFATAL to avoid single-use symbol (refactor)
- move output argument `state` to the end of `testBlockValidity`, see https://github.com/bitcoin/bitcoin/pull/30200#discussion_r1647987176
ACKs for top commit:
AngusP:
Code Review ACK a74b0f93ef
itornaza:
Tested ACK a74b0f93ef
ryanofsky:
Code review ACK a74b0f93ef. Just new error string is added since last review, and a commit message was updated
Tree-SHA512: 805e133bb59303fcee107d6f02b3e2761396c290efb731a85e6a29ae56b4b1b9cd28ada9629e979704dcfd98cf35034e7e6b618e29923049eb1eca2f65630e41
73f0a6cbd0 doc: detail -rpccookieperms option (willcl-ark)
d2afa2690c test: add rpccookieperms test (willcl-ark)
f467aede78 init: add option for rpccookie permissions (willcl-ark)
7df03f1a92 util: add perm string helper functions (willcl-ark)
Pull request description:
This PR picks up #26088 by aureleoules which adds a bitcoind launch option `-rpccookieperms` to set the file permissions of the cookie generated by bitcoin core.
Example usage to make the generated cookie group-readable: `./src/bitcoind -rpccookieperms=group`.
Accepted values for `-rpccookieperms` are `[owner|group|all]`. We let `fs::perms` handle platform-specific permissions changes.
ACKs for top commit:
achow101:
ACK 73f0a6cbd0
ryanofsky:
Code review ACK 73f0a6cbd0. Main change since last review is no longer throwing a skip exception in the rpc test on windows, so other checks can run after it, and overall test result is passing, not skipped. Also were clarifying renames and documentation improvements.
tdb3:
cr ACK 73f0a6cbd0
Tree-SHA512: e800d59a44aca10e1c58ca69bf3fdde9f6ccf5eab4b7b962645af6d6bc0cfa3a357701e409c8c60d8d7744fcd33a91e77ada11790aa88cd7811ef60fab86ab11
This allows a transaction's weight to be bound under a certain
weight if possible and desired. This can be beneficial for future
RBF attempts, or whenever a more restricted spend topology is
desired.
Co-authored-by: Greg Sanders <gsanders87@gmail.com>
The goal of interfaces is to eventually run in their own process,
so we can't use EXCLUSIVE_LOCKS_REQUIRED in their declaration.
However TestBlockValidaty will crash (in its call to ConnectBlock)
if the tip changes from under the proposed block.
Have the testBlockValidity implementation hold the lock instead,
and non-fatally check for this condition.
GetFirstStoredBlock is generalized to check for any data status with a
status mask that needs to be passed as a parameter. To reflect this the
function is also renamed to GetFirstBlock.
Co-authored-by: stickies-v <stickies-v@protonmail.com>
Set tip at the start of the function and only update it for a long poll.
Additionally have getTipHash return an optional, so the
caller can explicitly check that a tip exists.
c7376babd1 doc: Clarify distinction between util and common libraries in libraries.md (Ryan Ofsky)
4f74c59334 util: Move util/string.h functions to util namespace (Ryan Ofsky)
4d05d3f3b4 util: add TransactionError includes and namespace declarations (Ryan Ofsky)
680eafdc74 util: move fees.h and error.h to common/messages.h (Ryan Ofsky)
02e62c6c9a common: Add PSBTError enum (Ryan Ofsky)
0d44c44ae3 util: move error.h TransactionError enum to node/types.h (Ryan Ofsky)
9bcce2608d util: move spanparsing.h to script/parsing.h (Ryan Ofsky)
6dd2ad4792 util: move spanparsing.h Split functions to string.h (Ryan Ofsky)
23cc8ddff4 util: move HexStr and HexDigit from util to crypto (TheCharlatan)
6861f954f8 util: move util/message to common/signmessage (Ryan Ofsky)
cc5f29fbea build: move memory_cleanse from util to crypto (Ryan Ofsky)
5b9309420c build: move chainparamsbase from util to common (Ryan Ofsky)
ffa27af24d test: Add check-deps.sh script to check for unexpected library dependencies (Ryan Ofsky)
Pull request description:
Remove `fees.h`, `errors.h`, and `spanparsing.h` from the util library. Specifically:
- Move `Split` functions from `util/spanparsing.h` to `util/string.h`, using `util` namespace for clarity.
- Move remaining spanparsing functions to `script/parsing.h` since they are used for descriptor and miniscript parsing.
- Combine `util/fees.h` and `util/errors.h` into `common/messages.h` so there is a place for simple functions that generate user messages to live, and these functions are not part of the util library.
Motivation for this change is that the util library is a dependency of the kernel, and we should remove functionality from util that shouldn't be called by kernel code or kernel applications. These changes should also improve code organization and make functions easier to discover. Some of these same moves are (or were) part of #28690, but did not help with code organization, or made it worse, so it is better to move them and clean them up in the same PR so code only has to change one time.
ACKs for top commit:
achow101:
ACK c7376babd1
TheCharlatan:
Re-ACK c7376babd1
hebasto:
re-ACK c7376babd1.
Tree-SHA512: 5bcef16c1255463b1b69270548711e7ff78ca0dd34e300b95e3ca1ce52ceb34f83d9ddb2839e83800ba36b200de30396e504bbb04fa02c6d0c24a16d06ae523d
429ec1aaaa refactor: Rename CTransaction::nVersion to version (Ava Chow)
27e70f1f5b consensus: Store transaction nVersion as uint32_t (Ava Chow)
Pull request description:
Given that the use of a transaction's nVersion is always as an unsigned int, it doesn't make sense to store it as signed and then cast it to unsigned everywhere it is used and displayed.
Since a few alternative implementations have recently been revealed to have made an error with this signedness that would have resulted in consensus failure, I think it makes sense for us to just make this always unsigned to make it clear that the version is treated as unsigned. This would also help us avoid future potential issues with signedness of this value.
I believe that this is safe and does not actually change what transactions would or would not be considered both standard and consensus valid. Within consensus, the only use of the version in consensus is in BIP68 validation which was already casting it to uint32_t. Within policy, although it is used as a signed int for the transaction version number check, I do not think that this change would change standardness. Standard transactions are limited to the range [1, 2]. Negative numbers would have fallen under the < 1 condition, but by making it unsigned, they are still non-standard under the > 2 condition.
Unsigned and signed ints are serialized and unserialized the same way so there is no change in serialization.
ACKs for top commit:
maflcko:
ACK 429ec1aaaa 🐿
glozow:
ACK 429ec1aaaa
shaavan:
ACK 429ec1aaaa💯
Tree-SHA512: 0bcd92a245d7d16c3665d2d4e815a4ef28207ad4a1fb46c6f0203cdafeab1b82c4e95e4bdce7805d80a4f4a46074f6542abad708e970550d38a00d759e3dcef1
In order to ensure that the change of nVersion to a uint32_t in the
previous commit has no effect, rename nVersion to version in this commit
so that reviewers can easily spot if a spot was missed or if there is a
check somewhere whose semantics have changed.
2451a217dd test: addmultisigaddress, coverage for script size limits (furszy)
53302a0981 bugfix: addmultisigaddress, add unsupported operation for redeem scripts over 520 bytes (furszy)
9be6065cc0 test: coverage for 16-20 segwit multisig scripts (furszy)
9d9a91c4ea rpc: bugfix, incorrect segwit redeem script size used in signrawtransactionwithkey (furszy)
0c9fedfc45 fix incorrect multisig redeem script size limit for segwit (furszy)
f7a173b578 test: rpc_createmultisig, decouple 'test_sortedmulti_descriptors_bip67' (furszy)
4f33dbd8f8 test: rpc_createmultisig, decouple 'test_mixing_uncompressed_and_compressed_keys' (furszy)
25a81705d3 test: rpc_createmultisig, remove unnecessary checkbalances() (furszy)
b5a3289433 test: refactor, multiple cleanups in rpc_createmultisig.py (furszy)
3635d43268 test: rpc_createmultisig, remove manual wallet initialization (furszy)
Pull request description:
Fixing https://github.com/bitcoin/bitcoin/issues/28250#issuecomment-1674830104 and more.
Currently, redeem scripts longer than 520 bytes, which are technically valid under segwit rules, have flaws in the following processes:
1) The multisig creation process fails to deduce the output descriptor, resulting in the generation of an incorrect descriptor. Additionally, the accompanying user warning is also inaccurate.
2) The `signrawtransactionwithkey` RPC command fail to sign them.
3) The legacy wallet `addmultisigaddress` wrongly discards them.
The issue arises because most of these flows are utilizing the legacy spkm keystore, which imposes
the [p2sh max redeem script size rule](ded6873340/src/script/signingprovider.cpp (L160)) on all scripts. Which blocks segwit redeem scripts longer than
the max element size in all the previously mentioned processes (`createmultisig`, `addmultisigaddress`, and
`signrawtransactionwithkey`).
This PR fixes the problem, enabling the creation of multisig output descriptors involving more than 15 keys and
allowing the signing of these scripts, along with other post-segwit redeem scripts that surpass the 520-byte
p2sh limit.
Important note:
Instead of adding support for these longer redeem scripts in the legacy wallet, an "unsupported operation"
error has been added. The reasons behind this decision are:
1) The introduction of this feature brings about a compatibility-breaking change that requires downgrade
protection; older wallets would be unable to interact with these "new" legacy wallets.
2) Considering the ongoing deprecation of the legacy spkm, this issue provides another compelling
reason to transition towards descriptors.
Testing notes:
To easily verify each of the fixes, I decoupled the tests into standalone commits. So they can be
cherry-picked on top of master. Where `rpc_createmultisig.py` (with and without the `--legacy-wallet`
arg) will fail without the bugs fixes commits.
Extra note:
The initial commits improves the `rpc_createmultisig.py` test in many ways. I found this test very
antiquated, screaming for an update and cleanup.
ACKs for top commit:
pinheadmz:
ACK 2451a217dd
theStack:
Code-review ACK 2451a217dd
achow101:
ACK 2451a217dd
Tree-SHA512: 71794533cbd46b3a1079fb4e9d190d3ea3b615de0cbfa443466e14f05e4616ca90e12ce2bf07113515ea8113e64a560ad572bb9ea9d4835b6fb67b6ae596167f
fa3169b073 rpc: Remove index-based Arg accessor (MarcoFalke)
Pull request description:
The index-based Arg accessor is redundant with the name-based one. It does not provide any benefit to the code reader, or otherwise, so remove it.
ACKs for top commit:
stickies-v:
re-ACK fa3169b073, addressed doc nits
achow101:
ACK fa3169b073
ryanofsky:
Code review ACK fa3169b073. One changes since last review are some documentation improvements
Tree-SHA512: f9da1c049dbf38c3b47a8caf8d24d195c2d4b88c7ec45a9ccfb78f1e39f29cb86869f84b308f6e49856b074c06604ab634c90eb89c9c93d2a8169e070aa1bd40
