make it a good debugger!

Need slight refactoring of blocking I/O interacting with the event
handler stuff.

We would like to have at least a status showing while downloading is
in progress, maybe a modal popup.

It might even be worth it to make a Y/N dialog box query.

https://github.com/paritytech/parity/pull/5307/files

https://hackage.haskell.org/package/mcl

seems pretty tricky to me

An Org mode document with descriptions and thoughts about
architecture, implementation details, etc.

Implement RETURNDATASIZE and RETURNDATACOPY.

In order to do more easily do interesting things in the debugger, we
should have a console that pops up on Enter and lets you inspect and
manipulate the state of the VM and the environment.

Basic commands:

[ ] list known contract addresses
[ ] see contract details
[ ] get storage slot

can't just call into the runtime code yo

Right now the big steppers just take single steps when there's no source map.

Should be easy.

See sc-forks/solidity-coverage#41 (comment)

Some small modifications to hevm should let us do precise coverage analysis of unit test suites.

Implementation thoughts...

• In the Stepper interpreter defined in UnitTest, after each instruction we would save the current code position (e.g., code hash and program counter).
• After completion, we would generate a coverage report by mapping all the code positions to source maps.
• If we also output the number of times a position was touched, along with gas cost, this would also be a way to do gas profiling.

Given that we don't have any blockhashes yet, I don't know if we need
to do anything.

Implement STATICCALL.

In interactive mode, show a gas counter.

We're getting there!

We should be able to create repositories when they don't exist, and also to automatically reset --hard the working tree if there are no conflicts with local changes.

The gitlib-cmdline library can do these things, but maybe we should just shell out in a trivial way.

Turns out that gitlib is both too complex for what we need, and too unsupported.

I made an external library https://github.com/lessrest/restless-git that could be adapted like this.

The name "context trace" isn't accurate and the current type is silly.

The current command syntax is a bit awkward...

Will need some crypto dependencies etc.

Running into an interesting issue when creating contracts with the .value() function when using DSTest.

I'd like to seed contracts with ether using the value field of the transaction, so I can limit payments to just the constructor, but checking the contract balance post-creation still shows a zero balance. transfer() of course works when I add a payable fallback, but I'd prefer to not have a payable fallback to avoid unintended ether transfers.

I made a test repo here https://github.com/ngmiller/dapp-value-test - with the relevant code here: https://github.com/ngmiller/dapp-value-test/blob/master/src/DappValueTest.t.sol#L11-L14

Results of dapp test:

+ dapp clean
+ rm -rf out
+ solc --overwrite ds-test/=lib/ds-test/src/ ds-test=lib/ds-test/src/index.sol --abi --bin --bin-runtime = -o out/ src/DappValueTest.t.sol
+ solc --overwrite ds-test/=lib/ds-test/src/ ds-test=lib/ds-test/src/index.sol --combined-json=abi,bin,bin-runtime,srcmap,srcmap-runtime,ast = src/DappValueTest.t.sol
+ solc --overwrite ds-test/=lib/ds-test/src/ ds-test=lib/ds-test/src/index.sol --abi --bin --bin-runtime = -o out/ src/DappValueTest.sol
+ solc --overwrite ds-test/=lib/ds-test/src/ ds-test=lib/ds-test/src/index.sol --combined-json=abi,bin,bin-runtime,srcmap,srcmap-runtime,ast = src/DappValueTest.sol
Running 2 tests for src/DappValueTest.t.sol:DappValueTestTest
FAIL test_balance()
PASS test_value() (gas: 3390)

Failure: test_balance

  "Error: Wrong `uint' value"
    Expected: ~1.00000000e18
      Actual: 0

  src/DappValueTest.t.sol:DappValueTestTest
   ├╴constructor
   ├╴initialize test
   │  └╴create DappValueTest (src/DappValueTest.t.sol:11)
   └╴test_balance()
      ├╴log_bytes32("Error: Wrong `uint' value") (lib/ds-test/src/test.sol:112)
      ├╴log_named_uint("  Expected", 1000000000000000000) (lib/ds-test/src/test.sol:113)
      └╴log_named_uint("    Actual", 0) (lib/ds-test/src/test.sol:114)

Linking with Solidity libraries requires loading code at particular addresses known in advance, which is right now possible through the Git state directory feature, but it should be thought through and then support should be implemented in dapp.

Turns out that the VMTests part of the Ethereum Foundation test
suite is made for the Homestead fork.

I don't know if the plan is to upgrade those tests to Metropolis, or
deprecate that whole suite... it's a bit confusing.

Now that we can load states, we could rather easily load that state over the network from an actual blockchain.

Some wreq requests and aeson fiddling should be enough for the fetching.

We should also be able to autofetch missing contracts and refresh. This would require turning the exec function into a kind of coroutine that supports fetching. We could then have different fetching behaviors, e.g. in the debugger we show a dialog asking about the fetch, etc.

Implement the special logic for the null sender and also CREATE2.

I guess the proper solution, since the tests run in parallel, is to
have a shared mutable cache. Using STM it should be pretty easy.

Needs to return data, similar to RETURN, but revert state changes.

We need a way to track which tests are failing.

I'm using hsevm to test my own manually written assembly and copy-pasting the bytecode manually into cli is cumbersome. -o option to load the file directly instead of --code would be useful.

This doesn't look helpful, but it's the only error message given.

FAIL test_transfer()

hevm: internal error: method type
CallStack (from HasCallStack):
  error, called at src/EVM/Solidity.hs:214:22 in hevm-0.12.3-F2xYvHyywk1C4HRq6dL7d:EVM.Solidity