Create a TestEngine

[shargon]

We have a problem creating unit tests, I'm going to make a testEngine to facilitate the testing of smart contracts.

• new Testing environment #890 . It will create a dll with the contract to be able to call it by code
• TestEngine: Get instruction coverage and move to net standard #898
• Nep17 UnitTests #893
• TestEngine: add Checkpoints, RpcStorage and Dump to html #904
• TestEngine: Compute coverage branches #936
• TestEngine: Source code coverage #937

Doc:

• https://github.com/neo-project/neo-devpack-dotnet/blob/master/src/Neo.SmartContract.Testing/README.md

Bugs found with this engine:

• bug: Fix default value when Stored #895
• Update and fix Nep17 template #891
• Optimize OnPersist neo#3145
• Fix if statement sequence points and SequencePointInserter #938

[cschuchardt88]

I will be creating an DebugApplicationEngine. After my TraceApplicationEngine. Just keep that in mind.

[shargon]

I will be creating an DebugApplicationEngine. After my TraceApplicationEngine. Just keep that in mind.

The underlying engine could be changed in a future easily in order to be more verbose.

[cschuchardt88]

I will be creating an DebugApplicationEngine. After my TraceApplicationEngine. Just keep that in mind.

The underlying engine could be changed in a future easily in order to be more verbose.

I already did that. Im not changing ApplicationEngine. I am however replacing it by doing ApplicationEngine.Provider = new TraceApplicationEngine());

All I am saying is, all this work you are doing can be done very easy with current code we have. It already built to handle something like this. I don't know why you reinventing the wheel again. When we have already made it.

[shargon]

I don't know why you reinventing the wheel again. When we have already made it.

I'm tired of seeing projects in neo without any unit tests, it's not easy to do them, show me a single project that has them, I think this wheel is not even being reinvented, if it is even designed.

[cschuchardt88]

Your misunderstanding it. I explained it incorrectly.

The TestEngine you are creating. Can be done with ease with IApplicationEngineProvider. All I am saying is build your Engine with that Interface. So you can plugin/hook into the ApplicationEngine protected or virtual methods for getting all the VMs information. I don't think I need to tell you the information you can get from ApplicationEngine. But this would be the real big test. Where you can test on mainnet or testnet without problems. I been working on TraceApplicationEngine for about a day. And was saying no one should reinvent all the functionality that ApplicationEngine has already. We have an Engine Its called ApplicationEngine. You should make TestApplicationEngine or ContractApplicationEngine. If that makes sense.

[roman-khimov]

IIUC that'd be something similar to https://pkg.go.dev/github.com/nspcc-dev/neo-go/pkg/neotest or https://neow3j.io/#/neo-n3/smart_contract_development/testing. But both have some real or almost real ledger behind, so invocations are real transactions packed into some blocks and processed in a regular way. Can you you provide more details on how DLL-packed contracts will work here?

[shargon]

IIUC that'd be something similar to https://pkg.go.dev/github.com/nspcc-dev/neo-go/pkg/neotest or https://neow3j.io/#/neo-n3/smart_contract_development/testing. But both have some real or almost real ledger behind, so invocations are real transactions packed into some blocks and processed in a regular way. Can you you provide more details on how DLL-packed contracts will work here?

The problem that we have been encountering throughout all the contracts reviewed is mainly the same, the contracts have not been tested, and the lack of unit tests.

What I am doing is the ability to generate some "artifacts" abstract class extracted from NefFile, in this way the testing is not limited to contracts made in C#, these artifacts generate a valid C# code descriptive of the Abi, and through mocks, I intend convert types between VM<>dotnet to facilitate calling and testing contracts.

The initial idea (it may evolve in a future version) is to test without generating a transaction, so if you want to simulate two transactions you would have to do something like this:

var walletA= new UInt160("a");
var walletA= new UInt160("b");
TestEngine engine=new ();

var contract = engine.Deploy<MyContract>();

engine.Signer= walletA;
contract.Mint();

engine.Signer= walletB;
Assert.IsFalse(contract.Transfer(walletA,walletB,1)); // no signed by a

engine.Signer= walletA;
Assert.IsTrue(contract.Transfer(walletA,walletB,1));

[shargon]

Here you can see how it will work:

https://github.com/neo-project/neo-devpack-dotnet/blob/f00d32a7eae7b739cf512f9c8d735ad84af38f19/tests/Neo.SmartContract.Testing.UnitTests/NativeArtifactsTests.cs

[Jim8y]

would be much better if you had provided a detailed introduction on what you are trying to do, and how it is supposed to work.

[cschuchardt88]

would be much better if you had provided a detailed introduction on what you are trying to do, and how it is supposed to work.

@shargon Yes we need more information. So you dont waste everyone's time, including yours.

[shargon]

would be much better if you had provided a detailed introduction on what you are trying to do, and how it is supposed to work.

Got it, next time I will do that. My goal is to make it easy unit tests for any smart contract, because trust me, there's a lack of this everywhere.

[cschuchardt88]

would be much better if you had provided a detailed introduction on what you are trying to do, and how it is supposed to work.

Got it, next time I will do that. My goal is to make it easy unit tests for any smart contract, because trust me, there's a lack of this everywhere.

That is fine. How are we to use it? How do we build tests now? How do we setup the environment? What is required of a test? Whats the convention of the API? How are files and configuration laid out?

[shargon]

That is fine. How are we to use it? How do we build tests now? How do we setup the environment? What is required of a test? Whats the convention of the API? How are files and configuration laid out?

I will write a Readme.md explaining the new testing environment

[shargon]

https://github.com/neo-project/neo-devpack-dotnet/blob/master/src%2FNeo.SmartContract.Testing%2FREADME.md please tell me if you need more information

[cschuchardt88]

@shargon can you add checkpoints to your engine?

[Jim8y]

@shargon can you add checkpoints to your engine?

BreakPoint? VM.Tests's engine can do that. Can be added in another pr if not added.

[shargon]

@shargon can you add checkpoints to your engine?

Only snapshots now, commit and rollback, but if you consider dump the storage to a json, and load from it a checkpoint, yes, it's possible to do that

[cschuchardt88]

Also can we have in binary file format? If not already.

[shargon]

Also can we have in binary file format? If not already.

Of course, it could be faster

[cschuchardt88]

Also can we have in binary file format? If not already.

Of course, it could be faster

I mean log file in binary format also.

[shargon]

I think that the testEngine is finished, let's move to the next step #949