Merge pull request #107 from andrewla/develop

Fixing large number behavior of format
BenjaminVanRyseghem · Oct 14, 2015 · 0c2d42c · 0c2d42c
2 parents 7d16321 + 4ab3161
commit 0c2d42c
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Showing 2 changed files with 68 additions and 3 deletions.
diff --git a/numbro.js b/numbro.js
@@ -66,6 +66,43 @@
         this._value = number;
     }
 
+    function zeroes(count) {
+        var i, ret = '';
+
+        for (i = 0; i < count; i++) {
+            ret += '0';
+        }
+
+        return ret;
+    }
+    /**
+     * Implementation of toFixed() for numbers with exponent > 21
+     *
+     *
+     */
+    function toFixedLarge(value, precision) {
+        var mantissa,
+            beforeDec,
+            afterDec,
+            exponent,
+            str;
+
+        str = value.toString();
+
+        mantissa = str.split('e')[0];
+        exponent  = str.split('e')[1];
+
+        beforeDec = mantissa.split('.')[0];
+        afterDec = mantissa.split('.')[1] || '';
+
+        str = beforeDec + afterDec + zeroes(exponent - afterDec.length);
+        if (precision > 0) {
+            str += '.' + zeroes(precision);
+        }
+
+        return str;
+    }
+
     /**
      * Implementation of toFixed() that treats floats more like decimals
      *
@@ -77,9 +114,16 @@
             optionalsRegExp,
             output;
 
-        //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);
+        if (value.toFixed(0).search('e') > -1) {
+            // Above 1e21, toFixed returns scientific notation, which
+            // is useless and unexpected
+            output = toFixedLarge(value, precision);
+        }
+        else {
+            //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);
+        }
 
         if (optionals) {
             optionalsRegExp = new RegExp('0{1,' + optionals + '}$');

diff --git a/tests/numbro/format.js b/tests/numbro/format.js
@@ -114,6 +114,27 @@ exports.format = {
                 [18823578.85, '6 a', '18823.6 k'],
                 [188235773.85, '6 a', '188236 k'],
 
+                // large numbers
+                [100, '0,0[.]0000','100'],
+                [1e23, '0,0[.]0000','100,000,000,000,000,000,000,000'],
+
+                [1e19, '0,0.0000','10,000,000,000,000,000,000.0000'],
+                [1e20, '0,0.0000','100,000,000,000,000,000,000.0000'],
+                [1e21, '0,0.0000','1,000,000,000,000,000,000,000.0000'],
+                [1e22, '0,0.0000','10,000,000,000,000,000,000,000.0000'],
+                [1e23, '0,0.0000','100,000,000,000,000,000,000,000.0000'],
+
+                [-1e19, '0,0.0000','-10,000,000,000,000,000,000.0000'],
+                [-1e20, '0,0.0000','-100,000,000,000,000,000,000.0000'],
+                [-1e21, '0,0.0000','-1,000,000,000,000,000,000,000.0000'],
+                [-1e22, '0,0.0000','-10,000,000,000,000,000,000,000.0000'],
+                [-1e23, '0,0.0000','-100,000,000,000,000,000,000,000.0000'],
+
+                [1.1e23, '0,0.0000','110,000,000,000,000,000,000,000.0000'],
+                [1.11e23, '0,0.0000','111,000,000,000,000,000,000,000.0000'],
+                [1.111e23, '0,0.0000','111,100,000,000,000,000,000,000.0000'],
+
+
         // Non-finite numbers
         [Infinity, '0.0', 'Infinity'],
         [-Infinity, '0.0', '-Infinity'],