WIP: a bit of tidying up

Author: petebacondarwin

src/ng/filter/filters.js

@@ -124,8 +124,6 @@ function currencyFilter($locale) {
      </file>
    </example>
  */
-
-
 numberFilter.$inject = ['$locale'];
 function numberFilter($locale) {
   var formats = $locale.NUMBER_FORMATS;
@@ -139,82 +137,84 @@ function numberFilter($locale) {
   };
 }
 
-var isValid = /^-?(\d+(\.\d*)?|\.\d+)(e[+-]?\d+)?$/i;
+var MAX_DIGITS = 22;
+var DECIMAL_SEP = '.';
+var ZERO_CHAR = '0';
+
 function parse(numStr) {
-  var parsedNumber = {};
-  var exponent, i, j, zeros;
+  var exponent = 0, digits, integerLen;
+  var e, i, j, zeros;
 
   // Decimal point?
-  if ((exponent = numStr.indexOf('.')) > -1) {
-    numStr = numStr.replace('.', '');
+  if ((e = numStr.indexOf(DECIMAL_SEP)) > -1) {
+    numStr = numStr.replace(DECIMAL_SEP, '');
   }
   // Exponential form?
   if ((i = numStr.search(/e/i)) > 0) {
     // Determine exponent.
-    if (exponent < 0) {
-      exponent = i;
-    }
-    exponent += +numStr.slice(i + 1);
+    if (e < 0) e = i;
+    e += +numStr.slice(i + 1);
     numStr = numStr.substring(0, i);
-  } else if (exponent < 0) {
+  } else if (e < 0) {
     // Integer.
-    exponent = numStr.length;
+    e = numStr.length;
   }
   // Determine leading zeros.
-  i = 0;
-  while (numStr.charAt(i) == '0') i++;
+  for (i = 0; numStr.charAt(i) == ZERO_CHAR; i++);
 
   if (i == (zeros = numStr.length)) {
     // Zero.
-    parsedNumber.digits = [parsedNumber.exponent = 0];
+    digits = [0];
+    integerLen = 1;
   } else {
     // Determine trailing zeros.
-    do {
-      zeros--;
-    } while (numStr.charAt(zeros) == '0');
-    parsedNumber.exponent = exponent - i - 1;
-    parsedNumber.digits = [];
+    while (numStr.charAt(--zeros) == ZERO_CHAR);
+    integerLen = e - i;
+    digits = [];
     // Convert string to array of digits without leading/trailing zeros.
-    j = 0;
-    while (i <= zeros) {
-      parsedNumber.digits[j++] = +numStr.charAt(i++);
+    for (j = 0; i <= zeros; i++, j++) {
+      digits[j] = +numStr.charAt(i);
     }
   }
-  return parsedNumber;
+
+  // if the overflow the maximum allowed digits then use an exponent
+  if (integerLen > MAX_DIGITS) {
+    digits = digits.splice(0, MAX_DIGITS - 1);
+    exponent = integerLen - 1;
+    integerLen = 1;
+  }
+
+  return { digits: digits, exponent: exponent, integerLen: integerLen };
 }
 
 function roundNumber(parsedNumber, fractionSize, minFrac, maxFrac) {
     var digit = 0;
     var digits = parsedNumber.digits;
-    var exponent = parsedNumber.exponent;
-    var fractionLen = digits.length - 1 - exponent;
+    var fractionLen = digits.length - parsedNumber.integerLen;
 
     // determine fractionSize if it is not specified
     if (isUndefined(fractionSize)) {
       fractionSize = Math.min(Math.max(minFrac, fractionLen), maxFrac);
     }
 
     // Cut off unwanted digits with rounding
-    while (fractionLen > fractionSize && digits.length) {
+    for (; fractionLen > fractionSize && digits.length; fractionLen--) {
       digit = digits.pop();
       // Round up if necessary
       if (digit >= 5) digits[digits.length - 1]++;
-      fractionLen--;
     }
 
-    if (digits.length === 0) {
+    if (!digits.length) {
       // We rounded to zero so reset the parsedNumber
-      parsedNumber.exponent = 0;
+      parsedNumber.integerLen = 1;
       // If the last removed digit was >= 5 then we need to round up
       if (digit >= 5) digits.push(1);
       // Pad out with the necessary zeros
       while (digits.length <= fractionSize) digits.unshift(0);
     }
 
-    while (fractionLen < fractionSize) {
-      digits.push(0);
-      fractionLen++;
-    }
+    // Pad out with zeros to get the required fraction length
+    for (; fractionLen < fractionSize; fractionLen++)  digits.push(0);
 
     // Do a final clear of any carrying, e.g. the last digit was rounded up to 10
     var carry = digits.reduceRight(function(carry, d, i, digits) {
@@ -224,13 +224,10 @@ function roundNumber(parsedNumber, fractionSize, minFrac, maxFrac) {
     }, 0);
     if (carry) {
       digits.unshift(carry);
-      parsedNumber.exponent++;
+      parsedNumber.integerLen++;
     }
 }
 
-var DECIMAL_SEP = '.';
-var MAX_DIGITS = 21;
-
 /**
  * Format a number into a string
  * @param  {number} number       The number to format
@@ -252,43 +249,39 @@ var MAX_DIGITS = 21;
 function formatNumber(number, pattern, groupSep, decimalSep, fractionSize) {
 
   if (isObject(number)) return '';
-  var isInfinity = number === Infinity || number === -Infinity;
-  if (!isInfinity && !isFinite(number)) return '';
+
   var isNegative = number < 0;
-  var isZero = false;
   number = Math.abs(number);
+
+  var isInfinity = number === Infinity;
+  if (!isInfinity && !isFinite(number)) return '';
+
+  var isZero = false;
   var numStr = number + '',
       formattedText = '',
-      realExponent = 0,
       parsedNumber;
 
   if (isInfinity) {
     formattedText = '\u221e';
   } else {
     parsedNumber = parse(numStr);
 
-    if (parsedNumber.exponent > MAX_DIGITS) {
-      parsedNumber.digits = parsedNumber.digits.splice(0, MAX_DIGITS - 1);
-      realExponent = parsedNumber.exponent;
-      parsedNumber.exponent = 0;
-    }
-
     roundNumber(parsedNumber, fractionSize, pattern.minFrac, pattern.maxFrac);
 
     var digits = parsedNumber.digits;
-    var exponent = parsedNumber.exponent;
+    var integerLen = parsedNumber.integerLen;
     var decimals = [];
     isZero = digits.reduce(function(isZero, d) { return isZero && !d; }, true);
 
     // pad zeros for small numbers
-    while (exponent < -1) {
+    while (integerLen < 0) {
       digits.unshift(0);
-      exponent++;
+      integerLen++;
     }
 
     // extract decimals digits
-    if (exponent >= 0) {
-      decimals = digits.splice(exponent + 1);
+    if (integerLen > 0) {
+      decimals = digits.splice(integerLen);
     } else {
       decimals = digits;
       digits = [0];
@@ -312,8 +305,8 @@ function formatNumber(number, pattern, groupSep, decimalSep, fractionSize) {
       formattedText += decimalSep + decimals.join('');
     }
 
-    if (realExponent) {
-      formattedText += 'e+' + realExponent;
+    if (parsedNumber.exponent) {
+      formattedText += 'e+' + parsedNumber.exponent;
     }
   }
   if (isNegative && !isZero) {
@@ -330,7 +323,7 @@ function padNumber(num, digits, trim) {
     num = -num;
   }
   num = '' + num;
-  while (num.length < digits) num = '0' + num;
+  while (num.length < digits) num = ZERO_CHAR + num;
   if (trim) {
     num = num.substr(num.length - digits);
   }