232f96f5c8doc: Add release notes for -avoidpartialspends (Karl-Johan Alm)e00b4699ccclean-up: Remove no longer used ivars from CInputCoin (Karl-Johan Alm)43e04d13b1wallet: Remove deprecated OutputEligibleForSpending (Karl-Johan Alm)0128121101test: Add basic testing for wallet groups (Karl-Johan Alm)59d6f7b4e2wallet: Switch to using output groups instead of coins in coin selection (Karl-Johan Alm)87ebce25d6wallet: Add output grouping (Karl-Johan Alm)bb629cb9dcAdd -avoidpartialspends and m_avoid_partial_spends (Karl-Johan Alm)65b3eda458wallet: Add input bytes to CInputCoin (Karl-Johan Alm)a443d7a0camoveonly: CoinElegibilityFilter into coinselection.h (Karl-Johan Alm)173e18a289utils: Add insert() convenience templates (Karl-Johan Alm) Pull request description: This PR adds an optional (off by default) `-avoidpartialspends` flag, which changes coin select to use output groups rather than outputs, where each output group corresponds to all outputs with the same destination. It is a privacy improvement, as each time you spend some output, any other output that is publicly associated with the destination (address) will also be spent at the same time, at the cost of fee increase for cases where coin select without group restriction would find a more optimal set of coins (see example below). For regular use without address reuse, this PR should have no effect on the user experience whatsoever; it only affects users who, for some reason, have multiple outputs with the same destination (i.e. address reuse). Nodes with this turned off will still try to avoid partial spending, if the fee of the resulting transaction is not greater than the fee of the original transaction. Example: a node has four outputs linked to two addresses `A` and `B`: * 1.0 btc to `A` * 0.5 btc to `A` * 1.0 btc to `B` * 0.5 btc to `B` The node sends 0.2 btc to `C`. Without `-avoidpartialspends`, the following coin selection will occur: * 0.5 btc to `A` or `B` is picked * 0.2 btc is output to `C` * 0.3 - fee is output to (unique change address) With `-avoidpartialspends`, the following will instead happen: * Both of (0.5, 1.0) btc to `A` or `B` is picked (one or the other pair) * 0.2 btc is output to `C` * 1.3 - fee is output to (unique change address) As noted, the pro here is that, assuming nobody sends to the address after you spend from it, you will only ever use one address once. The con is that the transaction becomes slightly larger in this case, because it is overpicking outputs to adhere to the no partial spending rule. This complements #10386, in particular it addresses @luke-jr and @gmaxwell's concerns in https://github.com/bitcoin/bitcoin/pull/10386#issuecomment-300667926 and https://github.com/bitcoin/bitcoin/pull/10386#issuecomment-302361381. Together with `-avoidreuse`, this fully addresses the concerns in #10065 I believe. Tree-SHA512: 24687a4490ba59cf4198ed90052944ff4996653a4257833bb52ed24d058b3e924800c9b3790aeb6be6385b653b49e304453e5d7ff960e64c682fc23bfc447621
Bitcoin Core integration/staging tree
What is Bitcoin?
Bitcoin is an experimental digital currency that enables instant payments to anyone, anywhere in the world. Bitcoin uses peer-to-peer technology to operate with no central authority: managing transactions and issuing money are carried out collectively by the network. Bitcoin Core is the name of open source software which enables the use of this currency.
For more information, as well as an immediately useable, binary version of the Bitcoin Core software, see https://bitcoincore.org/en/download/, or read the original whitepaper.
License
Bitcoin Core is released under the terms of the MIT license. See COPYING for more information or see https://opensource.org/licenses/MIT.
Development Process
The master branch is regularly built and tested, but is not guaranteed to be
completely stable. Tags are created
regularly to indicate new official, stable release versions of Bitcoin Core.
The contribution workflow is described in CONTRIBUTING.md.
Testing
Testing and code review is the bottleneck for development; we get more pull requests than we can review and test on short notice. Please be patient and help out by testing other people's pull requests, and remember this is a security-critical project where any mistake might cost people lots of money.
Automated Testing
Developers are strongly encouraged to write unit tests for new code, and to
submit new unit tests for old code. Unit tests can be compiled and run
(assuming they weren't disabled in configure) with: make check. Further details on running
and extending unit tests can be found in /src/test/README.md.
There are also regression and integration tests, written
in Python, that are run automatically on the build server.
These tests can be run (if the test dependencies are installed) with: test/functional/test_runner.py
The Travis CI system makes sure that every pull request is built for Windows, Linux, and macOS, and that unit/sanity tests are run automatically.
Manual Quality Assurance (QA) Testing
Changes should be tested by somebody other than the developer who wrote the code. This is especially important for large or high-risk changes. It is useful to add a test plan to the pull request description if testing the changes is not straightforward.
Translations
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