Fixes problem with many optional decimals

When using a format with many optional decimals, insignificant trailing
digits could be added to the number:
Ex:
numeral(3162.63).format('0.0[000000000000]') = "3162.6300000000001"

Also changed numerals internal toFixed method to never return
trailing decimal points.

Also fixed a bug where an extra optional decimal was being added when
using a specified abbreviation.

numeral.js

@@ -39,17 +39,29 @@
      * Fixes binary rounding issues (eg. (0.615).toFixed(2) === '0.61') that present
      * problems for accounting- and finance-related software.
      */
-    function toFixed (value, precision, roundingFunction, optionals) {
-        var power = Math.pow(10, precision),
+    function toFixed (value, maxDecimals, roundingFunction, optionals) {
+        var splitValue = value.toString().split('.'),
+            minDecimals = maxDecimals - (optionals || 0),
+            boundedPrecision,
             optionalsRegExp,
+            power,
             output;
-
+
+        // Use the smallest precision value possible to avoid errors from floating point representation
+        if (splitValue.length === 2) {
+          boundedPrecision = Math.min(Math.max(splitValue[1].length, minDecimals), maxDecimals);
+        } else {
+          boundedPrecision = minDecimals;
+        }
+
+        power = Math.pow(10, boundedPrecision);
+
         //roundingFunction = (roundingFunction !== undefined ? roundingFunction : Math.round);
         // Multiply up by precision, round accurately, then divide and use native toFixed():
-        output = (roundingFunction(value * power) / power).toFixed(precision);
+        output = (roundingFunction(value * power) / power).toFixed(boundedPrecision);
 
-        if (optionals) {
-            optionalsRegExp = new RegExp('0{1,' + optionals + '}$');
+        if (optionals > maxDecimals - boundedPrecision) {
+            optionalsRegExp = new RegExp('\\.?0{1,' + (optionals - (maxDecimals - boundedPrecision)) + '}$');
             output = output.replace(optionalsRegExp, '');
         }
 
@@ -276,11 +288,10 @@
                 // check for space before abbreviation
                 if (format.indexOf(' a') > -1) {
                     abbr = ' ';
-                    format = format.replace(' a', '');
-                } else {
-                    format = format.replace('a', '');
                 }
 
+                format = format.replace(new RegExp(abbr + 'a[KMBT]?'), '');
+
                 if (abs >= Math.pow(10, 12) && !abbrForce || abbrT) {
                     // trillion
                     abbr = abbr + languages[currentLanguage].abbreviations.trillion;
@@ -357,7 +368,7 @@
 
                 w = d.split('.')[0];
 
-                if (d.split('.')[1].length) {
+                if (d.indexOf('.') > -1) {
                     d = languages[currentLanguage].delimiters.decimal + d.split('.')[1];
                 } else {
                     d = '';

tests/numeral/format.js

@@ -57,6 +57,9 @@ exports.format = {
                 [-0.23,'(.00)','(.23)'],
                 [0.23,'0.00000','0.23000'],
                 [0.67,'0.0[0000]','0.67'],
+                [3162.63,'0.0[00000000000000]','3162.63'],
+                [1.99,'0.[0]','2'],
+                [1.0501,'0.00[0]','1.05'],
                 [2000000000,'0.0a','2.0b'],
                 [1230974,'0.0a','1.2m'],
                 [1460,'0a','1k'],
@@ -70,7 +73,8 @@ exports.format = {
                 [-5444333222111, '0,0 aK', '-5,444,333,222 k'],
                 [-5444333222111, '0,0 aM', '-5,444,333 m'],
                 [-5444333222111, '0,0 aB', '-5,444 b'],
-                [-5444333222111, '0,0 aT', '-5 t']
+                [-5444333222111, '0,0 aT', '-5 t'],
+                [123456, '0.0[0] aK', '123.46 k'],
             ],
             i;