mount: Add test for parseMountFlagsAndOptions

Create a new unit test for `parseMountFlagsAndOptions()`. This involved
dropping the `error` return value since the function cannot fail.

Signed-off-by: James O. D. Hunt <[email protected]>

agent.go

@@ -1177,9 +1177,9 @@ func mountToRootfs(m initMount) error {
 		return err
 	}
 
-	if flags, options, err := parseMountFlagsAndOptions(m.options); err != nil {
-		return grpcStatus.Errorf(codes.Internal, "Could not parseMountFlagsAndOptions(%v)", m.options)
-	} else if err := syscall.Mount(m.src, m.dest, m.fstype, uintptr(flags), options); err != nil {
+	flags, options := parseMountFlagsAndOptions(m.options)
+
+	if err := syscall.Mount(m.src, m.dest, m.fstype, uintptr(flags), options); err != nil {
 		return grpcStatus.Errorf(codes.Internal, "Could not mount %v to %v: %v", m.src, m.dest, err)
 	}
 	return nil

mount.go

@@ -158,7 +158,7 @@ func ensureDestinationExists(source, destination string, fsType string) error {
 	return nil
 }
 
-func parseMountFlagsAndOptions(optionList []string) (int, string, error) {
+func parseMountFlagsAndOptions(optionList []string) (int, string) {
 	var (
 		flags   int
 		options []string
@@ -174,7 +174,7 @@ func parseMountFlagsAndOptions(optionList []string) (int, string, error) {
 		options = append(options, opt)
 	}
 
-	return flags, strings.Join(options, ","), nil
+	return flags, strings.Join(options, ",")
 }
 
 func parseOptions(optionList []string) map[string]string {
@@ -320,10 +320,7 @@ func commonStorageHandler(storage pb.Storage) (string, error) {
 
 // mountStorage performs the mount described by the storage structure.
 func mountStorage(storage pb.Storage) error {
-	flags, options, err := parseMountFlagsAndOptions(storage.Options)
-	if err != nil {
-		return err
-	}
+	flags, options := parseMountFlagsAndOptions(storage.Options)
 
 	return mount(storage.Source, storage.MountPoint, storage.Fstype, flags, options)
 }

mount_test.go

@@ -308,3 +308,43 @@ func TestMount(t *testing.T) {
 		}
 	}
 }
+
+func TestMountParseMountFlagsAndOptions(t *testing.T) {
+	assert := assert.New(t)
+
+	type testData struct {
+		options []string
+
+		expectedFlags   int
+		expectedOptions string
+	}
+
+	// Start with some basic tests
+	data := []testData{
+		{[]string{}, 0, ""},
+		{[]string{"moo"}, 0, "moo"},
+		{[]string{"moo", "foo"}, 0, "moo,foo"},
+		{[]string{"foo", "moo"}, 0, "foo,moo"},
+	}
+
+	// Add the expected flag handling tests
+	for name, value := range flagList {
+		td := testData{
+			options:         []string{"foo", name, "bar"},
+			expectedFlags:   value,
+			expectedOptions: "foo,bar",
+		}
+
+		data = append(data, td)
+	}
+
+	for i, d := range data {
+		msg := fmt.Sprintf("test[%d]: %+v\n", i, d)
+
+		flags, options := parseMountFlagsAndOptions(d.options)
+
+		assert.Equal(d.expectedFlags, flags, msg)
+		assert.Equal(d.expectedOptions, options, msg)
+
+	}
+}