AngularJS Unit tests Unit test a filter
Example
Filter code:
angular.module('myModule', []).filter('multiplier', function() {
return function(number, multiplier) {
if (!angular.isNumber(number)) {
throw new Error(number + " is not a number!");
}
if (!multiplier) {
multiplier = 2;
}
return number * multiplier;
}
});
The test:
describe('multiplierFilter', function() {
var filter;
beforeEach(function() {
module('myModule');
inject(function(multiplierFilter) {
filter = multiplierFilter;
});
});
it('multiply by 2 by default', function() {
expect(filter(2)).toBe(4);
expect(filter(3)).toBe(6);
});
it('allow to specify custom multiplier', function() {
expect(filter(2, 4)).toBe(8);
});
it('throws error on invalid input', function() {
expect(function() {
filter(null);
}).toThrow();
});
});
Remark: In the inject call in the test, your filter needs to be specified by its name + Filter. The cause for this is that whenever you register a filter for your module, Angular register it with a Filter appended to its name.
