Update VirtualBox driver ssh_port helper

Be more restrictive when matching the port forward used for
SSH. Allow matching simply on the guest port, but also include
extra matching criteria for cases where multiple results may
be returned.

plugins/providers/virtualbox/driver/version_5_0.rb

@@ -689,12 +689,21 @@ module VagrantPlugins
         def ssh_port(expected_port)
           @logger.debug("Searching for SSH port: #{expected_port.inspect}")
 
-          # Look for the forwarded port only by comparing the guest port
-          read_forwarded_ports.each do |_, _, hostport, guestport|
-            return hostport if guestport == expected_port
-          end
+          # Look for the forwarded port. Valid based on the guest port, but will do
+          # scoring based matching to determine best value when multiple results are
+          # available.
+          matches = read_forwarded_ports.map do |_, name, hostport, guestport, host_ip|
+            next if guestport != expected_port
+            match = [0, hostport]
+            match[0] += 1 if name == "ssh"
+            match[0] += 1 if name.downcase == "ssh"
+            match[0] += 1 if host_ip == "127.0.0.1"
+            match
+          end.compact
 
-          nil
+          result = matches.sort_by(&:first).last
+
+          result.last if result
         end
 
         def resume

test/unit/plugins/providers/virtualbox/driver/version_5_0_test.rb

@@ -79,4 +79,57 @@ describe VagrantPlugins::ProviderVirtualBox::Driver::Version_5_0 do
       end
     end
   end
+
+  describe "#ssh_port" do
+    let(:forwards) {
+      [[1, "ssh", 2222, 22, "127.0.0.1"],
+        [1, "ssh", 8080, 80, ""]]
+    }
+
+    before { allow(subject).to receive(:read_forwarded_ports).and_return(forwards) }
+
+    it "should return the host port" do
+      expect(subject.ssh_port(22)).to eq(2222)
+    end
+
+    context "when multiple matches are available" do
+      let(:forwards) {
+        [[1, "ssh", 2222, 22, "127.0.0.1"],
+          [1, "", 2221, 22, ""]]
+      }
+
+      it "should choose localhost port forward" do
+        expect(subject.ssh_port(22)).to eq(2222)
+      end
+
+      context "when multiple named matches are available" do
+        let(:forwards) {
+          [[1, "ssh", 2222, 22, "127.0.0.1"],
+            [1, "SSH", 2221, 22, "127.0.0.1"]]
+        }
+
+        it "should choose lowercased name forward" do
+          expect(subject.ssh_port(22)).to eq(2222)
+        end
+      end
+    end
+
+    context "when only ports are defined" do
+      let(:forwards) {
+        [[1, "", 2222, 22, ""]]
+      }
+
+      it "should return the host port" do
+        expect(subject.ssh_port(22)).to eq(2222)
+      end
+    end
+
+    context "when no matches are available" do
+      let(:forwards) { [] }
+
+      it "should return nil" do
+        expect(subject.ssh_port(22)).to be_nil
+      end
+    end
+  end
 end