Persona filter tests and pass-through behavior

Allow the persona filter to pass invalid account URIs through unharmed.

h/static/scripts/filters.coffee

@@ -26,8 +26,12 @@ momentFilter = ->
 
 
 persona = (user, part='username') ->
-  part = ['term', 'username', 'provider'].indexOf(part)
-  (user?.match /^acct:([^@]+)@(.+)/)?[part]
+  index = ['term', 'username', 'provider'].indexOf(part)
+  groups = user?.match /^acct:([^@]+)@(.+)/
+  if groups
+    groups[index]
+  else if part != 'provider'
+    user
 
 
 angular.module('h')

tests/js/filters-test.coffee

+assert = chai.assert
+sinon.assert.expose assert, prefix: null
+
+describe 'persona', ->
+  filter = null
+  term = 'acct:hacker@example.com'
+
+  beforeEach module('h')
+  beforeEach inject ($filter) ->
+    filter = $filter('persona')
+
+  it 'should return the whole term by request', ->
+    assert.equal filter('acct:hacker@example.com', 'term'), 'acct:hacker@example.com'
+
+  it 'should return the requested part', ->
+    assert.equal filter(term), 'hacker'
+    assert.equal filter(term, 'term'), term,
+    assert.equal filter(term, 'username'), 'hacker'
+    assert.equal filter(term, 'provider'), 'example.com'
+
+  it 'should pass through unrecognized terms as username or term', ->
+    assert.equal filter('bogus'), 'bogus'
+    assert.equal filter('bogus', 'username'), 'bogus'
+
+  it 'should handle error cases', ->
+    assert.notOk filter()
+    assert.notOk filter('bogus', 'provider')