Moved from flag module singleton usage to FlagSet and fixed tests.

flagger.go

@@ -27,6 +27,7 @@ import (
 	// stdlib
 	"errors"
 	"flag"
+	"os"
 	"sync"
 )
 
@@ -45,13 +46,14 @@ type Flagger struct {
 	flagsBool   map[string]*bool
 	flagsInt    map[string]*int
 	flagsString map[string]*string
+
+	flagSet *flag.FlagSet
 }
 
-// Adds flag to list of flags we will pass to ``flag`` package.
+// AddFlag adds flag to list of flags we will pass to ``flag`` package.
 func (f *Flagger) AddFlag(flag *Flag) error {
 	_, present := f.flags[flag.Name]
 	if present {
-		logger.Fatal("Cannot add flag '" + flag.Name + "' - already added!")
 		return errors.New("Cannot add flag '" + flag.Name + "' - already added!")
 	}
 
@@ -59,7 +61,7 @@ func (f *Flagger) AddFlag(flag *Flag) error {
 	return nil
 }
 
-// This function returns boolean value for flag with given name.
+// GetBoolValue returns boolean value for flag with given name.
 // Returns bool value for flag and nil as error on success
 // and false bool plus error with text on error.
 func (f *Flagger) GetBoolValue(name string) (bool, error) {
@@ -70,7 +72,7 @@ func (f *Flagger) GetBoolValue(name string) (bool, error) {
 	return (*fl), nil
 }
 
-// This function returns integer value for flag with given name.
+// GetIntValue returns integer value for flag with given name.
 // Returns integer on success and 0 on error.
 func (f *Flagger) GetIntValue(name string) (int, error) {
 	fl, present := f.flagsInt[name]
@@ -80,7 +82,7 @@ func (f *Flagger) GetIntValue(name string) (int, error) {
 	return (*fl), nil
 }
 
-// This function returns string value for flag with given name.
+// GetStringValue returns string value for flag with given name.
 // Returns string on success or empty string on error.
 func (f *Flagger) GetStringValue(name string) (string, error) {
 	fl, present := f.flagsString[name]
@@ -90,7 +92,7 @@ func (f *Flagger) GetStringValue(name string) (string, error) {
 	return (*fl), nil
 }
 
-// Flagger initialization.
+// Initialize initializes Flagger.
 func (f *Flagger) Initialize() {
 	logger.Print("Initializing CLI parameters parser...")
 
@@ -99,28 +101,35 @@ func (f *Flagger) Initialize() {
 	f.flagsBool = make(map[string]*bool)
 	f.flagsInt = make(map[string]*int)
 	f.flagsString = make(map[string]*string)
+
+	f.flagSet = flag.NewFlagSet("flagger", flag.ContinueOnError)
 }
 
-// This function adds flags from flags map to flag package and parse
+// Parse adds flags from flags map to flag package and parse
 // them. They can be obtained later by calling GetTYPEValue(name),
 // where TYPE is one of Bool, Int, String.
 func (f *Flagger) Parse() {
+	// If flags was already parsed - do nothing.
+	if f.flagSet.Parsed() {
+		return
+	}
+
 	for name, fl := range f.flags {
 		if fl.Type == "bool" {
 			fdef := fl.DefaultValue.(bool)
 			f.flagsBool[name] = &fdef
-			flag.BoolVar(&fdef, name, fdef, fl.Description)
+			f.flagSet.BoolVar(&fdef, name, fdef, fl.Description)
 		} else if fl.Type == "int" {
 			fdef := fl.DefaultValue.(int)
 			f.flagsInt[name] = &fdef
-			flag.IntVar(&fdef, name, fdef, fl.Description)
+			f.flagSet.IntVar(&fdef, name, fdef, fl.Description)
 		} else if fl.Type == "string" {
 			fdef := fl.DefaultValue.(string)
 			f.flagsString[name] = &fdef
-			flag.StringVar(&fdef, name, fdef, fl.Description)
+			f.flagSet.StringVar(&fdef, name, fdef, fl.Description)
 		}
 	}
 
 	logger.Print("Parsing CLI parameters...")
-	flag.Parse()
+	f.flagSet.Parse(os.Args)
 }