How I can do steps in the truffle test?

Question

I'm testing AMM, so I have steps like

1. add liquidity,
2. try to swap
3. remove liquidity

etc

I can just add it in one it block like this answer suggests

contract('amm', (accounts) => {
    it ("test all three steps", async () => {
        // await step 1
        // await step 2
        // await step 3
    })
})

however the test output would in one block together, which isn't very informative. I can't use several It blocks because one steps depends on previous one.

Mocha has steps for that purpose, what's the truffle analog, if any?

Answer 1

Using several it blocks is exactly what you need in the given scenario. If I understand correctly, then your testing document should look like something like this:

contract('amm', (accounts) =>{
  var tokenInstance;

      it('adds the funds', ()=> {
        return AMMToken.deployed().then((instance)=> {
          tokenInstance = instance;
          return tokenInstance.addFund(12);
        }).then((addFundReceipt)=> {
          assert.equal(addFundReceipt.success, true, 'fund added correctly');
      });
    });

      it('performs the swap',()=> {
        return AMMToken.deployed().then((instance)=> {
          tokenInstance = instance;
          return tokenInstance.swap(to,from);
        }).then((SwapFundReceipt)=>{
          assert.equal(SwapFundReceipt.success, true, 'fund added correctly');
      });
    });

Using the above structure, in every call, you can set your Arrange and Act by calling tokenInstance.callYourFunction(ARRANGED values) and Assert in the succeeding promise. Since truffle comes with Chai Assertion Library, its very intuitive to use it. Also, if there are other steps that need to be performed before adding your funds like validating if funds are available, then you can test them all before calling. Since your Assert statements have a statement to go with it, if any of the assertions fail, you will see exactly what failed, this solves the problem of your block being "non-informative".

I personally have never got over promises. I keep coming back to it when writing tests.