blockchain.cpp has low unit test coverage. This commit is intended
to start improving its code coverage to reasonable levels. One or more
follow up commits will complete the task that this commit is starting
(though the usefulness of this commit is not dependent upon later
commits).
Note that these tests were not written based upon a specification of how
GetDifficulty *should* work, but rather how it actually *does* work. As
a result, if there are any bugs in the current GetDifficulty
implementation, these unit tests serve to lock them in rather than
expose them.
-- Why has blockchain.cpp been modified if this is a unit testing change?
Since the existing GetDifficulty function relies on a global variable,
chainActive, it was not suitable for unit testing purposes. Both the
existing GetDifficulty function and the unit tests now call through to
a new, more modular version of GetDifficulty that can work on any chain,
not just chainActive.
-- Why does blockchain_tests.cpp directly include blockchain.cpp instead
of blockchain.h?
While the new GetDifficulty function's signature is arguably better than
the old one's, it still isn't great, and doesn't seem to warrant inclusion
as part of the blockchain.h API, especially since only test code is
directly using it. If a better way of exposing the new GetDifficulty
function to unit tests exists, please mention it and the commit will be
updated accordingly.
-- Why is the test fixture named blockchain_difficulty_tests rather than
blockchain_tests?
The Bitcoin Core policy for naming unit test files is to match the the
file under test ("blockchain" becomes "blockchain_tests"). While this
commit complies with that, blockchain.cpp is a massive file, such that
having all of the unit tests in one file will tend towards disorder.
Since there will be a lot more tests added to this file, the intention
is to divide up different types of tests into different test fixtures
within the same file.
1. The RPC help text should use the constant CURRENCY_UNIT defined in
policy/feerate.cpp instead of the literal 'BTC'. In the following
2 RPC commands, 'BTC' is written directly in the help text.
1) estimatesmartfee
2) estimaterawfee
And also, for these help strings, the notation
'fee-per-kilobyte (in BTC)' is somewhat ambiguous.
To write more precisely, this commit changes to 'fee rate in BTC/kB'
with using the constant CURRENCY_UNIT.
2. Some RPC command use 'satoshis' as the unit. It should be written
as 'satoshis' instead of 'Satoshis' in the RPC help text.
So, this commit fixes this typo in getblocktemplate.
3. The phrase that '... feerate (BTC per KB) ...' is used to explain
the fee rate in the help text of following 2 RPC commands.
1) getmempoolinfo
2) fundrawtransaction
But they are different from other similar help text of the RPCs.
And also, 'KB' implies Kibibyte (2^10 byte).
To unify and to clarify, this commit changes these phrase to
'... fee rate in BTC/kB ...'.
(BTC references the constant 'CURRENCY_UNIT')
This contains most of the changes of 10563 "remove safe mode", but doesn't
remove the safe mode yet, but put an `ObserveSafeMode()` check in
individual calls with okSafeMode=false.
This cleans up the ugly "okSafeMode" flag from the dispatch tables,
which is not a concern for the RPC server.
Extra-author: Wladimir J. van der Laan <laanwj@gmail.com>
1. Calculate nblocks more adaptive.
If not specify nblocks-parameter, illegal parameter error
will happen when target block height is below blocks for 1 month.
To avoid this error, set default nblocks to
min(blocks for 1 month, target block's height - 1)
And allowing 0 so that this RPC works good even if target block is
genesis block or 1st block.
2. Correct error message.
nblocks accepts [0 .. block's height -1] . so fix as following:
"Invalid block count: should be between 0 and the block's height - 1"
3. Add check 0-divide.
If nTimeDiff = 0 then returns {... "txrate":} and
bitcoin-cli cannot handle the response.
To avoid this error, do not return "txrate" if nTimeDiff = 0.
4. Add following 3 elements to the return object.
1) 'window_block_count' : Size of the window in number of blocks.
2) 'window_tx_count' : The number of transactions in the window.
3) 'window_interval' : The elapsed time in the window.
They clarify how 'txrate' is calculated. 2) and 3) are returned
only if 'window_block_count' is a positive value.
5. Improve help text for 'time' as following.
'The timestamp for the final block in the window in UNIX format.
CCoinsViewCache doesn't actually support cursor iteration returning the
current contents of the cache, so raise an error when the cursor method is
called instead of returning a cursor that iterates over stale data.
Also update the gettxoutsetinfo RPC which was relying on the old behavior to be
explicit about which view it is returning data about.
Just Wonder