Merge branch 'bug/ldap_dn_matches_filter' into 'master'

Handle LDAP errors in Adapter#dn_matches_filter?

CHANGELOG-EE

+v 6.7.1
+  - Handle LDAP errors in Adapter#dn_matches_filter?
+
 v 6.7.0
   - Improve LDAP sign-in speed by reusing connections
   - Add support for Active Directory nested LDAP groups

lib/gitlab/ldap/adapter.rb

@@ -107,7 +107,12 @@ module Gitlab
       end
 
       def dn_matches_filter?(dn, filter)
-        ldap.search(base: dn, filter: filter, attributes: %w{dn}).any?
+        results = ldap.search(base: dn, filter: filter, attributes: %w{dn})
+        if results.nil?
+          false # Net::LDAP encountered an LDAP error
+        else
+          results.any?
+        end
       end
 
       private

spec/lib/gitlab/ldap/ldap_adapter_spec.rb

+require 'spec_helper'
+
+describe Gitlab::LDAP::Adapter do
+  let(:adapter) { Gitlab::LDAP::Adapter.new }
+
+  describe :dn_matches_filter? do
+    let(:ldap) { double(:ldap) }
+    subject { adapter.dn_matches_filter?(:dn, :filter) }
+    before { adapter.stub(ldap: ldap) }
+
+    context "when the search is successful" do
+      context "and the result is non-empty" do
+        before { ldap.stub(search: [:foo]) }
+
+        it { should be_true }
+      end
+
+      context "and the result is empty" do
+        before { ldap.stub(search: []) }
+
+        it { should be_false }
+      end
+    end
+
+    context "when the search encounters an error" do
+      before { ldap.stub(search: nil) }
+
+      it { should be_false }
+    end
+  end
+end