diff --git a/.eslintrc b/.eslintrc
index fa220bd7afcca..aca4fe1acdef9 100644
--- a/.eslintrc
+++ b/.eslintrc
@@ -47,11 +47,13 @@
     "eqeqeq": ["error", "always"],
     "no-caller": "error",
     "no-else-return": "error",
+    "no-empty-pattern": "error",
     "no-eval": "error",
     "no-extend-native": "error",
     "no-extra-bind": "error",
     "no-extra-label": "error",
     "no-fallthrough": "error",
+    "no-floating-decimal": "error",
     "no-global-assign": "error",
     "no-implied-eval": "error",
     "no-lone-blocks": "error",
@@ -64,6 +66,7 @@
     "no-octal": "error",
     "no-redeclare": "error",
     "no-self-assign": "error",
+    "no-self-compare": "error",
     "no-unused-expressions": "error",
     "no-unused-labels": "error",
     "no-useless-call": "error",
@@ -76,6 +79,7 @@
 
     // Variables
     "no-catch-shadow": "error",
+    "no-delete-var": "error",
     "no-label-var": "error",
     "no-shadow-restricted-names": "error",
     "no-undef-init": "error",
@@ -97,6 +101,7 @@
     "new-parens": "error",
     "no-array-constructor": "error",
     "no-multiple-empty-lines": ["error", { "max": 2, "maxEOF": 0, "maxBOF": 1, }],
+    "no-new-object": "error",
     "no-tabs": "error",
     "no-trailing-spaces": ["error", { "skipBlankLines": false, }],
     "no-whitespace-before-property": "error",
diff --git a/src/core/fonts.js b/src/core/fonts.js
index db272718e208d..796d1f38a673e 100644
--- a/src/core/fonts.js
+++ b/src/core/fonts.js
@@ -2121,7 +2121,7 @@ var Font = (function FontClosure() {
               op >= 0xC0 && op <= 0xDF ? -1 : op >= 0xE0 ? -2 : 0;
             if (op >= 0x71 && op <= 0x75) {
               n = stack.pop();
-              if (n === n) {
+              if (!isNaN(n)) {
                 stackDelta = -n * 2;
               }
             }