Merge pull request #2239 from yurydelendik/no-glyphs-message

Stops font processing when valid glyphs are absent in the font

src/evaluator.js

@@ -161,7 +161,7 @@ var PartialEvaluator = (function PartialEvaluatorClosure() {
           translated = this.translateFont(font, xref, resources,
                                           dependency);
         } catch (e) {
-          translated = { error: e };
+          translated = { error: e instanceof Error ? e.message : e };
         }
         font.translated = translated;
 

src/fonts.js

@@ -3557,6 +3557,10 @@ var Font = (function FontClosure() {
         this.glyphNameMap = properties.glyphNameMap;
       }
 
+      if (ids.length === 0) {
+        error('Valid glyph data is not found');
+      }
+
       // Converting glyphs and ids into font's cmap table
       cmap.data = createCMapTable(glyphs, ids);
       var unicodeIsEnabled = [];