The first should address a long term issue where we recommend a gas
price that is greater than that required for 50% of transactions in
recent blocks, which can lead to gas price inflation as people take
this figure and add a margin to it, resulting in a positive feedback
loop.
* eth, internal: Implement using trie diffs
* eth, internal: Changes in response to review
* eth: More fixes to getModifiedAccountsBy*
* eth: minor polishes on error capitalization
This PR implements a differenceIterator, which allows iterating over trie nodes
that exist in one trie but not in another. This is a prerequisite for most GC
strategies, in order to find obsolete nodes.
This commit introduces a FindOnce method for filters. FindOnce finds the next block that
matches the filter and returns all matching logs from that block. If there are no further
matching logs, it returns a nil slice. This method allows callers to iterate over large
sets of logs progressively.
The changes introduce a small inefficiency relating to mipmaps: the first time a filter is
called, it acts as if all mipmaps are matched, and thus iterates several blocks near the
requested start point. This is in the interest of simplicity and avoiding duplicate mipmap
lookups each time FindOnce is called.
This CL makes several refactors:
- Define a Tracer interface, implementing the `CaptureState` method
- Add the VM environment as the first argument of
`Tracer.CaptureState`
- Rename existing functionality `StructLogger` an make it an
implementation of `Tracer`
- Delete `StructLogCollector` and make `StructLogger` collect the logs
directly
- Change all callers to use the new `StructLogger` where necessary and
extract logs from that.
- Deletes the apparently obsolete and likely nonfunctional 'TraceCall'
from the eth API.
Callers that only wish accumulated logs can use the `StructLogger`
implementation straightforwardly. Callers that wish to efficiently
capture VM traces and operate on them without excessive copying can now
implement the `Tracer` interface to receive VM state at each step and
do with it as they wish.
This CL also removes the accumulation of logs from the vm.Environment;
this was necessary as part of the refactor, but also simplifies it by
removing a responsibility that doesn't directly belong to the
Environment.
This is necessary for external users of the go-ethereum code who want to, for instance, build a custom node that plays back transactions, as core.ApplyTransaction requires a ChainConfig as a parameter.
Nick JohnsonandFelix Lange
