How do your retrieve nested CPI/Inner Instructions from web3.js?

Question

From solana web3.js, it looks like it only shows 1 level deep of CPI.

How would I get inner ix 2 in this example:

tx:
  ix1:
    inner ix1:
      inner ix2:
  ix2:
    ...

  type ConfirmedTransactionMeta = {
    ...
    /** An array of cross program invoked instructions */
    innerInstructions?: CompiledInnerInstruction[] | null;
    ...
  };
    
  type CompiledInnerInstruction = {
    index: number;
    instructions: CompiledInstruction[];
  };
  
  type CompiledInstruction = {
    /** Index into the transaction keys array indicating the program account that executes this instruction */
    programIdIndex: number;
    /** Ordered indices into the transaction keys array indicating which accounts to pass to the program */
    accounts: number[];
    /** The program input data encoded as base 58 */
    data: string;
  };

Answer 1

Take a look at how the innerInstructions are returned from this example https://docs.solana.com/developing/clients/jsonrpc-api#notification-format-1

So you're very close! The index in CompiledInnerInstruction gives the index of the instruction in the top-level transaction, so to get inner ix 2, which is the second inner instruction in the first top-level instruction, you'd look at innerInstructions[0].instructions[1], and make sure that innerInstructions[0].index === 0.