Hiddenchars (#221)

* Fix bug where an icons font is counted as two unused unicode ranges
* Display the number of hidden chars

lib/tools/redownload/redownload.js

@@ -500,6 +500,8 @@ var Redownload = function() {
                 var ranges = [];
                 var others = null;
                 var rangeNames = Object.keys(req.fontMetrics.unicodeRanges);
+                var unicodePointsCount = 0;
+                var unusedRangesInFont = 0;
                 
                 rangeNames.forEach(function(rangeName) {
                     var range = req.fontMetrics.unicodeRanges[rangeName];
@@ -508,18 +510,20 @@ var Redownload = function() {
                     if (rangeName === 'Others') {
                         if (range.numGlyphsInCommonWithPageContent === 0 && range.charset.length > 50) {
                             range.underused = true;
-                            unusedUnicodeRanges ++;
+                            unusedRangesInFont ++;
                         }
 
+                        unicodePointsCount += range.charset.length;
                         others = range;
                     } else if (range.charset.length > 0) {
                         // Now lets detect if the current Unicode range is unused.
                         // Reminder: range.coverage = glyphs declared in this range, divided by the range size
                         if (range.coverage > 0.25 && range.numGlyphsInCommonWithPageContent === 0) {
                             range.underused = true;
-                            unusedUnicodeRanges ++;
+                            unusedRangesInFont ++;
                         }
 
+                        unicodePointsCount += range.charset.length;
                         ranges.push(range);
                     }
                 });
@@ -539,7 +543,7 @@ var Redownload = function() {
 
                     // And if less than 5% of the icons are used, let's report it as underused
                     if (others && others.numGlyphsInCommonWithPageContent / others.charset.length <= 0.05) {
-                        unusedUnicodeRanges ++;
+                        unusedRangesInFont = 1;
                     }
 
                 // Not an icons font
@@ -549,13 +553,21 @@ var Redownload = function() {
                         ranges.push(others);
                     }
 
+                    var ligaturesOrHiddenChars = req.fontMetrics.numGlyphs - unicodePointsCount;
+                    if (ligaturesOrHiddenChars > 25) {
+                        unusedUnicodeRanges ++;
+                    }
+
                     list.push({
                         url: req.url,
                         weight: req.weightCheck.bodySize,
                         isIconFont: false,
-                        unicodeRanges: ranges
+                        unicodeRanges: ranges,
+                        ligaturesOrHiddenChars: ligaturesOrHiddenChars 
                     });
                 }
+
+                unusedUnicodeRanges += unusedRangesInFont;
             }
         });