templateFormatString: do not error out when lookup objects are undefined

Author: antoinerg

Diff for: src/lib/index.js

@@ -1031,6 +1031,7 @@ var TEMPLATE_STRING_FORMAT_SEPARATOR = /^[:|\|]/;
 function templateFormatString(string, labels, d3locale) {
     var opts = this;
     var args = arguments;
+    if(!labels) labels = {};
     // Not all that useful, but cache nestedProperty instantiation
     // just in case it speeds things up *slightly*:
     var getterCache = {};
@@ -1039,6 +1040,7 @@ function templateFormatString(string, labels, d3locale) {
         var obj, value, i;
         for(i = 3; i < args.length; i++) {
             obj = args[i];
+            if(!obj) continue;
             if(obj.hasOwnProperty(key)) {
                 value = obj[key];
                 break;

Diff for: test/jasmine/tests/lib_test.js

@@ -2250,14 +2250,24 @@ describe('Test lib.js:', function() {
             }
             expect(Lib.warn.calls.count()).toBe(10);
         });
+
+        it('does not error out when arguments are undefined', function() {
+            expect(function() {
+                Lib.hovertemplateString('y: %{y}', undefined, locale, undefined);
+            }).not.toThrow();
+        });
     });
 
     describe('texttemplateString', function() {
+        var locale = false;
         it('evaluates attributes', function() {
-            var locale = false;
             expect(Lib.texttemplateString('foo %{bar}', {}, locale, {bar: 'baz'})).toEqual('foo baz');
         });
 
+        it('looks for default label if no format is provided', function() {
+            expect(Lib.texttemplateString('y: %{y}', {yLabel: '0.1'}, locale, {y: 0.123})).toEqual('y: 0.1');
+        });
+
         it('warns user up to 10 times if a variable cannot be found', function() {
             spyOn(Lib, 'warn').and.callThrough();
             Lib.texttemplateString('%{idontexist}', {});