UT: Lots of improvements and fixes.

- Parse negative amounts.
- Make Amount.negate() return a new value.
- Add Amount.equals().
- Rename Remote.trace() to set_trace().
- Fix request_ripple_balnce.
- Add more tests to send-test.js.
- Add more tests to amount-test.js.
- Add helper functions create_accounts and credit_limits to
  testutils.js.

js/amount.js

@@ -38,6 +38,10 @@ UInt160.prototype.copyTo = function(d) {
   return d;
 };
 
+UInt160.prototype.equals = function(d) {
+  return this.value === d.value;
+};
+
 // value = NaN on error.
 UInt160.prototype.parse_json = function (j) {
   // Canonicalize and validate
@@ -166,6 +170,12 @@ var Amount = function () {
   this.issuer	    = new UInt160();
 };
 
+// Given "100/USD/mtgox" return the a string with mtgox remapped.
+Amount.text_full_rewrite = function (j) {
+  return Amount.from_json(j).to_text_full();
+}
+
+// Given "100/USD/mtgox" return the json.
 Amount.json_rewrite = function(j) {
   return Amount.from_json(j).to_json();
 };
@@ -174,15 +184,18 @@ Amount.from_json = function(j) {
   return (new Amount()).parse_json(j);
 };
 
-Amount.prototype.clone = function() {
-  return this.copyTo(new Amount());
+Amount.prototype.clone = function(negate) {
+  return this.copyTo(new Amount(), negate);
 };
 
 // Returns copy.
-Amount.prototype.copyTo = function(d) {
+Amount.prototype.copyTo = function(d, negate) {
   if ('object' === typeof this.value)
   {
-    this.value.copyTo(d.value);
+    if (this.is_native && negate)
+      this.value.negate.copyTo(d.value);
+    else
+      this.value.copyTo(d.value);
   }
   else
   {
@@ -191,7 +204,7 @@ Amount.prototype.copyTo = function(d) {
 
   d.offset	= this.offset;
   d.is_native	= this.is_native;
-  d.is_negative	= this.is_negative;
+  d.is_negative	= this.is_negative ? undefined : !this.is_negative;
 
   this.currency.copyTo(d.currency);
   this.issuer.copyTo(d.issuer);
@@ -266,15 +279,13 @@ Amount.prototype.canonicalize = function() {
       this.offset += 1;
     }
   }
+
+  return this;
 };
 
+// Return a new value.
 Amount.prototype.negate = function () {
-  if (this.is_native) {
-    this.value.negate();
-  }
-  else {
-    this.is_negative  = !this.is_negative;
-  }
+  return this.clone('NEGATE');
 };
 
 Amount.prototype.to_json = function() {
@@ -307,23 +318,26 @@ Amount.prototype.parse_native = function(j) {
   var m;
 
   if ('string' === typeof j)
-    m = j.match(/^(\d+)(\.\d{1,6})?$/);
+    m = j.match(/^(-?)(\d+)(\.\d{1,6})?$/);
 
   if (m) {
-    if (undefined === m[2]) {
+    if (undefined === m[3]) {
       // Integer notation
 
-      this.value	  = new BigInteger(m[1]);
+      this.value	  = new BigInteger(m[2]);
     }
     else {
       // Decimal notation
 
-      var   int_part	  = (new BigInteger(m[1])).multiply(exports.consts.bi_xns_unit);
-      var   fraction_part = (new BigInteger(m[2])).multiply(new BigInteger(String(Math.pow(10, 1+exports.consts.xns_precision-m[2].length))));
+      var   int_part	  = (new BigInteger(m[2])).multiply(exports.consts.bi_xns_unit);
+      var   fraction_part = (new BigInteger(m[3])).multiply(new BigInteger(String(Math.pow(10, 1+exports.consts.xns_precision-m[3].length))));
 
       this.value	  = int_part.add(fraction_part);
     }
 
+    if (m[1])
+      this.value  = this.value.negate();
+
     this.is_native    = true;
     this.offset	      = undefined;
     this.is_negative  = undefined;
@@ -442,6 +456,20 @@ Amount.prototype.parse_issuer = function (issuer) {
   return this;
 };
 
+// Check BigInteger NaN
+Amount.prototype.equals = function (d) {
+  return 'string' === typeof (d)
+    ? this.equals(Amount.from_json(d))
+    : this === d
+      || (d.constructor === Amount
+	&& this.is_native === d.is_native
+	&& (this.is_native
+	    ? this.value.equals(d.value)
+	    : this.is_negative === d.is_negative
+	      ? this.value.equals(d.value)
+	      : this.value.equals(BigInteger.ZERO) && d.value.equals(BigInteger.ZERO)));
+};
+
 exports.Amount	      = Amount;
 exports.Currency      = Currency;
 exports.UInt160	      = UInt160;

js/remote.js

@@ -244,8 +244,8 @@ Remote.prototype._set_state = function (state) {
   }
 };
 
-Remote.prototype.trace = function () {
-  this.trace  = true;
+Remote.prototype.set_trace = function (trace) {
+  this.trace  = undefined === trace || trace;
 
   return this;
 };
@@ -731,6 +731,8 @@ Remote.prototype.dirty_account_root = function (account) {
 // --> issuer: String
 // --> currency: String
 // --> current: bool : true = current ledger
+//
+// If does not exist: emit('error', 'error' : 'remoteError', 'remote' : { 'error' : 'entryNotFound' })
 Remote.prototype.request_ripple_balance = function (account, issuer, currency, current) {
   var request	    = this.request_ledger_entry('ripple_state');	  // YYY Could be cached per ledger.
 
@@ -739,20 +741,25 @@ Remote.prototype.request_ripple_balance = function (account, issuer, currency, c
     .ledger_choose(current)
     .on('success', function (message) {
 	var node	    = message.node;
+
 	var lowLimit	    = Amount.from_json(node.LowLimit);
 	var highLimit	    = Amount.from_json(node.HighLimit);
+	// The amount account holds of issuer (after negation if needed).
 	var balance	    = Amount.from_json(node.Balance);
-	var flip	    = UInt160.from_json(account) == highLimit.issuer;
-	var issuerLimit	    = flip ? lowLimit : highLimit;
-	var accountLimit    = flip ? highLimit : lowLimit;
-	var issuerBalance   = (flip ? balance.negate() : balance).parse_issuer(issuer);
-	var accountBalance  = issuerBalance.clone().parse_issuer(issuer);
+	// accountHigh implies: for account: balance is negated, highLimit is the limit set by account.
+	var accountHigh	    = UInt160.from_json(account).equals(highLimit.issuer);
+	// The limit set by issuer.
+	var issuerLimit	    = (accountHigh ? lowLimit : highLimit).parse_issuer(issuer);
+	// The limit set by account.
+	var accountLimit    = (accountHigh ? highLimit : lowLimit).parse_issuer(account);
+	var issuerBalance   = (accountHigh ? balance.negate() : balance).parse_issuer(issuer);
+	var accountBalance  = issuerBalance.clone().negate().parse_issuer(account);
 
 	request.emit('ripple_state', {
-	  'issuer_balance'  : issuerBalance,				  // Balance with dst as issuer.
-	  'account_balance' : accountBalance,				  // Balance with account as issuer.
-	  'issuer_limit'    : issuerLimit.clone().parse_issuer(account),  // Limit set by issuer with src as issuer.
-	  'account_limit'   : accountLimit.clone().parse_issuer(issuer)	  // Limit set by account with dst as issuer.
+	  'issuer_balance'  : issuerBalance,  // Balance with dst as issuer.
+	  'account_balance' : accountBalance, // Balance with account as issuer.
+	  'issuer_limit'    : issuerLimit,    // Limit set by issuer with src as issuer.
+	  'account_limit'   : accountLimit    // Limit set by account with dst as issuer.
 	});
       });
 }
@@ -774,7 +781,7 @@ Remote.prototype.transaction = function () {
 //  Events:
 // 'success' : Transaction submitted without error.
 // 'error' : Error submitting transaction.
-// 'proposed: Advisory proposed status transaction.
+// 'proposed' : Advisory proposed status transaction.
 // - A client should expect 0 to multiple results.
 // - Might not get back. The remote might just forward the transaction.
 // - A success could be reverted in final.
@@ -1115,7 +1122,7 @@ Transaction.prototype.ripple_line_set = function (src, limit, quality_in, qualit
 
   // Allow limit of 0 through.
   if (undefined !== limit)
-    this.transaction.LimitAmount  = limit.to_json();
+    this.transaction.LimitAmount  = Amount.json_rewrite(limit);
 
   if (quality_in)
     this.transaction.QualityIn	  = quality_in;