Async options retrieval error is handled through this.error()

README.md

@@ -149,6 +149,7 @@ var ldapOpts = {
 ## Asynchronous configuration retrieval
 
 Instead of providing a static configuration object, you can pass a function as `options` that will take care of fetching the configuration. It will be called with the `req` object and a callback function having the standard `(err, result)` signature. Notice that the provided function will be called on every authenticate request.
+If the function returns an error, the authentication request will error out with that error.
 
 ```javascript
 var getLDAPConfiguration = function(req, callback) {

lib/passport-ldapauth/strategy.js

@@ -346,7 +346,7 @@ Strategy.prototype.authenticate = function(req, options) {
 
   var callback = function(err, configuration) {
     if (err) {
-      return this.fail(err);
+      return this.error(err);
     }
 
     this.options = setDefaults(configuration);

test/strategy-test.js

@@ -324,6 +324,25 @@ describe('LDAP authentication strategy', function() {
     });
   });
 
+  describe('with options as function returning an error', function() {
+    var opts = function(cb) {
+      process.nextTick(function() {
+        cb(new Error('What a terrible failure'));
+      });
+    };
+
+    before(start_servers(opts, BASE_TEST_OPTS));
+    after(stop_servers);
+
+    it('should fail the authentication with an error', function(cb) {
+      request(expressapp)
+        .post('/login')
+        .send({username: 'valid', password: 'valid'})
+        .expect(500)
+        .end(cb);
+    });
+  });
+
   describe('with group fetch settings defined', function() {
     var OPTS;