Support stellar-core protocol 12

[abuiles]

Add support for stellar-core protocol 12 release and CAP 24 ("Make PathPayment Symmetrical").

Add ➕

• Operation.pathPaymentStrictSend: Sends a path payment, debiting from the source account exactly a specified amount of one asset, crediting at least a given amount of another asset.

  The following operation will debit exactly 10 USD from the source account, crediting at least 9.2 EUR in the destination account 💸:

  var sendAsset = new StellarBase.Asset(
    'USD',
    'GDGU5OAPHNPU5UCLE5RDJHG7PXZFQYWKCFOEXSXNMR6KRQRI5T6XXCD7'
  );
  var sendAmount = '10';
  var destination =
    'GCEZWKCA5VLDNRLN3RPRJMRZOX3Z6G5CHCGSNFHEYVXM3XOJMDS674JZ';
  var destAsset = new StellarBase.Asset(
    'USD',
    'GDGU5OAPHNPU5UCLE5RDJHG7PXZFQYWKCFOEXSXNMR6KRQRI5T6XXCD7'
  );
  var destMin = '9.2';
  var path = [
    new StellarBase.Asset(
      'USD',
      'GBBM6BKZPEHWYO3E3YKREDPQXMS4VK35YLNU7NFBRI26RAN7GI5POFBB'
    ),
    new StellarBase.Asset(
      'EUR',
      'GDTNXRLOJD2YEBPKK7KCMR7J33AAG5VZXHAJTHIG736D6LVEFLLLKPDL'
    )
  ];
  let op = StellarBase.Operation.pathPaymentStrictSend({
    sendAsset,
    sendAmount,
    destination,
    destAsset,
    destMin,
    path
  });

• Operation.pathPaymentStrictReceive: This behaves the same as the former pathPayments operation.

  The following operation will debit maximum 10 USD from the source account, crediting exactly 9.2 EUR in the destination account 💸:

  var sendAsset = new StellarBase.Asset(
    'USD',
    'GDGU5OAPHNPU5UCLE5RDJHG7PXZFQYWKCFOEXSXNMR6KRQRI5T6XXCD7'
  );
  var sendMax = '10';
  var destination =
    'GCEZWKCA5VLDNRLN3RPRJMRZOX3Z6G5CHCGSNFHEYVXM3XOJMDS674JZ';
  var destAsset = new StellarBase.Asset(
    'USD',
    'GDGU5OAPHNPU5UCLE5RDJHG7PXZFQYWKCFOEXSXNMR6KRQRI5T6XXCD7'
  );
  var destAmount = '9.2';
  var path = [
    new StellarBase.Asset(
      'USD',
      'GBBM6BKZPEHWYO3E3YKREDPQXMS4VK35YLNU7NFBRI26RAN7GI5POFBB'
    ),
    new StellarBase.Asset(
      'EUR',
      'GDTNXRLOJD2YEBPKK7KCMR7J33AAG5VZXHAJTHIG736D6LVEFLLLKPDL'
    )
  ];
  let op = StellarBase.Operation.pathPaymentStrictReceive({
    sendAsset,
    sendMax,
    destination,
    destAsset,
    destAmount,
    path
  });

Deprecated ❗️

• Operation.pathPayment is being deprecated in favor of Operation.pathPaymentStrictReceive. Both functions take the same arguments and behave the same.

[marcinx]

Beautiful! I was just about to ask :)

[bartekn]

LGTM, just one question.

[bartekn]

Suggested change

	The following operation will debit exactly $10 USD from the source acount, crediting at least $9.2 EUR in the destination account 💸:
	The following operation will debit exactly 10 USD from the source acount, crediting at least 9.2 EUR in the destination account 💸:

[abuiles]

@bartekn oh, good catch! I won't apply the suggestion but do it as a commit on my machine since I used $ somewhere else