7918c1b019 test: Add CreateWalletFromFile test (Russell Yanofsky)
Pull request description:
Add unit test calling CreateWalletFromFile, which isn't currently called from other unit tests, with some basic checks to make sure it rescans and registers for notifications correctly.
Motivation for this change was to try to write a test that would fail without the early `handleNotifications` call in ef8c6ca60767cac589d98ca57ee33179608ccda8 from https://github.com/bitcoin/bitcoin/pull/16426, but succeed with it:
ef8c6ca607/src/wallet/wallet.cpp (L3978-L3986)
However, writing a full test for the race condition that call prevents isn't possible without the locking changes from #16426. So this PR just adds as much test coverage as is possible now.
This new test is also useful for https://github.com/bitcoin/bitcoin/pull/15719, since it detects the stale notifications.transactionAddedToMempool notifications that PR eliminates.
ACKs for top commit:
MarcoFalke:
ACK 7918c1b019
jonatack:
ACK 7918c1b019
Tree-SHA512: 44035aee698ecb722c6039d061d8fac2011e9da0b314e4aff19be1d610b53cacff99016b34d6b84669bb3b61041b2318d9d8e3363658f087802ae4aa36ca17b8
0f204dd3f2