In line with previous commits we are progressively removing the
mutateState argument from this call stack for a more principled
software design approach.
NOTE FOR REVIEWERS:
We take a naive approach to updating the tests here and simply
take the functionality we are removing from evaluateHTLCView and
run it directly after the function in the test suite.
It's possible that we should instead remove this from the test
suite altogether but I opted to take a more conservative approach
with respect to reducing the scope of tests. If you have opinions
here, please make them known.
The purpose of this commit is to begin the process of packing
symmetric fields into the newly introduced Dual structure. The
reason for this is that the Dual structure has a handy indexing
method where we can supply a ChannelParty and get back a value.
This will cut down on the amount of branching code in the main
lines of the codebase logic, making it easier to follow what is
going on.
The objective of this commit is to make paymentDescriptor a private
data structure so we can quarantine it to the lnwallet package.
To accomplish this we had to prevent it from leaking out via the
arguments or return values of the public functions in lnwallet.
This naturally had consequences for the htlcswitch package as we
choose other mechanisms for tracking the data that paymentDescriptor
was responsible for.
Astoundingly, this was highly successful and allowed us to remove
a ton of redundant code. The diff for this commit represents a
substantial reduction in total lines of code as well as extraneous
arguments and return values from key functions.
This also sets the stage for future commits where we actually will
be attempting to rid lnwallet of paymentDescriptor completely.
Here we add a function that is capable of recovering LogUpdates from
paymentDescriptors and we refactor the lnwallet code to use this
rather than doing JIT inline construction of the LogUpdates.
In this commit we track the ChannelID on the PaymentDescriptor.
This will be useful in upcoming commits that need to be able to
reconstruct lnwire.Message values from PaymentDescriptors as the
Messages that are exchanged to update channel state all include
the ChannelID.
In this commit, we add a TLV blob to the PaymentDescriptor struct. We also now thread through this value from the UpdateAddHTLC message to the PaymentDescriptor mapping, and the other way around.
