test numeric HTML entity conversion in IE

Author: alexcjohnson

src/lib/svg_text_utils.js

@@ -301,17 +301,16 @@ function convertEntities(_str) {
 }
 exports.convertEntities = convertEntities;
 
-// but also in other browsers we don't want to overflow
-var stringFromCodePoint = String.fromCodePoint;
-var stringFromCharCode = String.fromCharCode;
 function fromCodePoint(code) {
     // Don't allow overflow. In Chrome this turns into � but I feel like it's
     // more useful to just not convert it at all.
     if(code > 0x10FFFF) return;
+    var stringFromCodePoint = String.fromCodePoint;
     if(stringFromCodePoint) return stringFromCodePoint(code);
 
     // IE doesn't have String.fromCodePoint
     // see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/fromCodePoint
+    var stringFromCharCode = String.fromCharCode;
     if(code <= 0xFFFF) return stringFromCharCode(code);
     return stringFromCharCode(
         (code >> 10) + 0xD7C0,

test/jasmine/tests/svg_text_utils_test.js

@@ -8,6 +8,16 @@ describe('svg+text utils', function() {
 
     describe('convertToTspans', function() {
 
+        var stringFromCodePoint;
+
+        beforeAll(function() {
+            stringFromCodePoint = String.fromCodePoint;
+        });
+
+        afterEach(function() {
+            String.fromCodePoint = stringFromCodePoint;
+        });
+
         function mockTextSVGElement(txt) {
             return d3.select('body')
                 .append('svg')
@@ -330,6 +340,28 @@ describe('svg+text utils', function() {
             expect(i).toBe(355);
         });
 
+        it('decodes arbitrary decimal and hex number entities (IE case)', function() {
+            // IE does not have String.fromCodePoint
+            String.fromCodePoint = undefined;
+            expect(String.fromCodePoint).toBeUndefined();
+
+            var i = 0;
+            for(var n = 33; n < 0x10FFFF; n = Math.round(n * 1.03)) {
+                var node = mockTextSVGElement(
+                    '&#x' + n.toString(16) +
+                    '; = &#' + n.toString() +
+                    '; = &#x' + n.toString(16).toUpperCase() + ';'
+                );
+                var char = stringFromCodePoint(n);
+                expect(node.text()).toBe(char + ' = ' + char + ' = ' + char, n);
+                i++;
+            }
+            // not really necessary to assert this, but we tested  355 characters,
+            // weighted toward the low end but continuing all the way to the
+            // end of the unicode definition
+            expect(i).toBe(355);
+        });
+
         it('does not decode entities prematurely', function() {
             var testCases = [
                 '&lt;b>not bold</b&gt;',