Add lock tests (#209)

* Add lock tests

* Refactor setLock to accept key value pairs

This allows SetCron and Lock to use the same function setLockValue. It
also removes the need to call getLock explicitly in tests by returning
the lock object.

internal/lock/lock.go

@@ -14,6 +14,10 @@ var lock *viper.Viper
 var file string
 var once sync.Once
 
+const (
+	RUNNING = "running"
+)
+
 func getLock() *viper.Viper {
 	if lock == nil {
 
@@ -37,36 +41,38 @@ func getLock() *viper.Viper {
 	return lock
 }
 
-func setLock(locked bool) error {
+func setLockValue(key string, value interface{}) (*viper.Viper, error) {
 	lock := getLock()
-	if locked {
-		running := lock.GetBool("running")
-		if running {
+
+	if key == RUNNING {
+		value := value.(bool)
+		if value && lock.GetBool(key) {
 			colors.Error.Println("an instance is already running. exiting")
 			os.Exit(1)
 		}
 	}
-	lock.Set("running", locked)
+
+	lock.Set(key, value)
 	if err := lock.WriteConfigAs(file); err != nil {
-		return err
+		return nil, err
 	}
-	return nil
+	return lock, nil
 }
 
 func GetCron(location string) int64 {
-	lock := getLock()
-	return lock.GetInt64("cron." + location)
+	return getLock().GetInt64("cron." + location)
 }
 
 func SetCron(location string, value int64) {
-	lock.Set("cron."+location, value)
-	lock.WriteConfigAs(file)
+	setLockValue("cron."+location, value)
 }
 
 func Lock() error {
-	return setLock(true)
+	_, err := setLockValue(RUNNING, true)
+	return err
 }
 
 func Unlock() error {
-	return setLock(false)
+	_, err := setLockValue(RUNNING, false)
+	return err
 }