Warning: Could not decode event

Support Contracts
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Some good news, I have found and fixed some of the errors I was getting. For the Simple ERC777 token example, both the Simple777Recipient.test.js and Simple777Sender.test.js had problems in the code lines that use expectEvent…

Simple777Recipient.test.js

    await this.token.send(holder, amount, data, { from: creator });
    this.recipient = await Simple777Recipient.new(this.token.address, { from: creator });
  });

it('sends to a contract from an externally-owned account', async function () {
    const amount = new BN(1000);
    const receipt = await this.token.send(this.recipient.address, amount, data, { from: holder });

    await expectEvent.inTransaction(receipt.tx, Simple777Recipient, 'DoneStuff', { from: holder, to: this.recipient.address, amount: amount, userData: data, operatorData: null });

    const recipientBalance = await this.token.balanceOf(this.recipient.address);
    recipientBalance.should.be.bignumber.equal(amount);
  });

I changed the 2nd parameter in expectEvent.inTransaction from Simple777Recipient to this.recipient and the DoneStuff event was found and the test passed. Similarly for Simple777Sender.test.js

I have not however been able to pass the Simple777Token.test.js test

   it('assigns the initial total supply to the creator', async function () {
    const totalSupply = await this.token.totalSupply();
    const creatorBalance = await this.token.balanceOf(creator);

    expect(creatorBalance).to.be.bignumber.equal(totalSupply);

    await expectEvent.inConstruction(this.token, 'Transfer', {
      from: ZERO_ADDRESS,
      to: creator,
      value: totalSupply,
    });
  });

Here is the output from truffle test:

 Contract: Simple777Token
    √ has a name (234ms)

    Events emitted during test:
    ---------------------------

    Warning: Could not decode event!

    Warning: Could not decode event!

    Simple777Token.Minted(
      operator: <indexed> 0x856bFAFaB009C586BA043d2202B734c1eb56bBdE (type: address),
      to: <indexed> 0x856bFAFaB009C586BA043d2202B734c1eb56bBdE (type: address),
      amount: 10000000000000000000000 (type: uint256),
      data: hex'' (type: bytes),
      operatorData: hex'' (type: bytes)
    )

    Simple777Token.Transfer(
      from: <indexed> 0x0000000000000000000000000000000000000000 (type: address),
      to: <indexed> 0x856bFAFaB009C586BA043d2202B734c1eb56bBdE (type: address),
      value: 10000000000000000000000 (type: uint256)
    )

Clearly the Transfer event is being fired. Yet expectEvent.inConstruction does not find this ‘Transfer’ event. Would you have any idea why the event is not found?