add method to allow running from go source, without flags, see #50

README.md

@@ -206,7 +206,6 @@ installed. See the following example:
 package main
 
 import (
-	"flag"
 	"os"
 	"testing"
 
@@ -214,21 +213,13 @@ import (
 )
 
 func TestMain(m *testing.M) {
-	args := os.Args
-	// args for godog
-	os.Args = []string{
-		args[0],
-		"-f", "progress",
-		"features",
-	}
-
-	status := godog.Run(func(s *godog.Suite) {
+	status := godog.RunWithOptions(func(s *godog.Suite) {
 		FeatureContext(s)
+	}, godog.Options{
+		Format: "progress",
+		Paths:  []string{"features"},
 	})
 
-	os.Args = args
-	flag.Parse()
-
 	if st := m.Run(); st > status {
 		status = st
 	}

cmd/godog/main.go

@@ -68,8 +68,10 @@ func main() {
 	var tags, format, output string
 	var concurrency int
 
-	flagSet := godog.FlagSet(&format, &tags, &defs, &sof, &noclr, &concurrency, &output)
+	flagSet := godog.FlagSet(&format, &tags, &defs, &sof, &noclr, &concurrency)
 	flagSet.BoolVar(&vers, "version", false, "Show current version.")
+	flagSet.StringVar(&output, "o", "", "Build and output test runner executable to given target path.")
+	flagSet.StringVar(&output, "output", "", "Build and output test runner executable to given target path.")
 
 	err := flagSet.Parse(os.Args[1:])
 	if err != nil {

examples/godogs/godogs_test.go

@@ -2,7 +2,6 @@
 package main
 
 import (
-	"flag"
 	"fmt"
 	"os"
 	"testing"
@@ -11,21 +10,13 @@ import (
 )
 
 func TestMain(m *testing.M) {
-	args := os.Args
-	// args for godog
-	os.Args = []string{
-		args[0],
-		"-f", "progress",
-		"features",
-	}
-
-	status := godog.Run(func(s *godog.Suite) {
+	status := godog.RunWithOptions(func(s *godog.Suite) {
 		FeatureContext(s)
+	}, godog.Options{
+		Format: "progress",
+		Paths:  []string{"features"},
 	})
 
-	os.Args = args
-	flag.Parse()
-
 	if st := m.Run(); st > status {
 		status = st
 	}

flags.go

@@ -23,11 +23,8 @@ var descTagsOption = "Filter scenarios by tags. Expression can be:\n" +
 	s(4) + "- " + cl(`"@wip && ~@new"`, yellow) + ": run wip scenarios, but exclude new\n" +
 	s(4) + "- " + cl(`"@wip,@undone"`, yellow) + ": run wip or undone scenarios"
 
-var descOutputOption = "Output the temporary test runner executable:\n" +
-	s(4) + "- supply the name to give the executable " + cl("test_features.exe", yellow) + "\n"
-
 // FlagSet allows to manage flags by external suite runner
-func FlagSet(format, tags *string, defs, sof, noclr *bool, cr *int, output *string) *flag.FlagSet {
+func FlagSet(format, tags *string, defs, sof, noclr *bool, cr *int) *flag.FlagSet {
 	descFormatOption := "How to format tests output. Available formats:\n"
 	for _, f := range formatters {
 		descFormatOption += s(4) + "- " + cl(f.name, yellow) + ": " + f.description + "\n"
@@ -45,8 +42,6 @@ func FlagSet(format, tags *string, defs, sof, noclr *bool, cr *int, output *stri
 	set.BoolVar(defs, "d", false, "Print all available step definitions.")
 	set.BoolVar(sof, "stop-on-failure", false, "Stop processing on first failed scenario.")
 	set.BoolVar(noclr, "no-colors", false, "Disable ansi colors.")
-	set.StringVar(output, "output", "", descOutputOption)
-	set.StringVar(output, "o", "", descOutputOption)
 	set.Usage = usage(set)
 	return set
 }

options.go

@@ -0,0 +1,18 @@
+package godog
+
+// Options are suite run options
+// flags are mapped to these options.
+//
+// It can also be used together with godog.RunWithOptions
+// to run test suite from go source directly
+//
+// See the flags for more details
+type Options struct {
+	ShowStepDefinitions bool
+	StopOnFailure       bool
+	NoColors            bool
+	Tags                string
+	Format              string
+	Concurrency         int
+	Paths               []string
+}

run.go

@@ -61,7 +61,58 @@ func (r *runner) run() (failed bool) {
 	return suite.failed
 }
 
+// RunWithOptions is same as Run function, except
+// it uses Options provided in order to run the
+// test suite without parsing flags
+//
+// This method is useful in case if you run
+// godog in for example TestMain function together
+// with go tests
+func RunWithOptions(contextInitializer func(suite *Suite), opt Options) int {
+	if opt.ShowStepDefinitions {
+		s := &Suite{}
+		contextInitializer(s)
+		s.printStepDefinitions()
+		return 0
+	}
+
+	if len(opt.Paths) == 0 {
+		inf, err := os.Stat("features")
+		if err == nil && inf.IsDir() {
+			opt.Paths = []string{"features"}
+		}
+	}
+
+	if opt.Concurrency > 1 && opt.Format != "progress" {
+		fatal(fmt.Errorf("when concurrency level is higher than 1, only progress format is supported"))
+	}
+	formatter, err := findFmt(opt.Format)
+	fatal(err)
+
+	features, err := parseFeatures(opt.Tags, opt.Paths)
+	fatal(err)
+
+	r := runner{
+		fmt:           formatter,
+		initializer:   contextInitializer,
+		features:      features,
+		stopOnFailure: opt.StopOnFailure,
+	}
+
+	var failed bool
+	if opt.Concurrency > 1 {
+		failed = r.concurrent(opt.Concurrency)
+	} else {
+		failed = r.run()
+	}
+	if failed {
+		return 1
+	}
+	return 0
+}
+
 // Run creates and runs the feature suite.
+// Reads all configuration options from flags.
 // uses contextInitializer to register contexts
 //
 // the concurrency option allows runner to
@@ -73,52 +124,18 @@ func (r *runner) run() (failed bool) {
 // contextInitializer must be able to register
 // the step definitions and event handlers.
 func Run(contextInitializer func(suite *Suite)) int {
-	var defs, sof, noclr bool
-	var tags, format, output string
-	var concurrency int
-	flagSet := FlagSet(&format, &tags, &defs, &sof, &noclr, &concurrency, &output)
+	var opt Options
+	flagSet := FlagSet(
+		&opt.Format,
+		&opt.Tags,
+		&opt.ShowStepDefinitions,
+		&opt.StopOnFailure,
+		&opt.NoColors,
+		&opt.Concurrency,
+	)
 	err := flagSet.Parse(os.Args[1:])
 	fatal(err)
+	opt.Paths = flagSet.Args()
 
-	if defs {
-		s := &Suite{}
-		contextInitializer(s)
-		s.printStepDefinitions()
-		return 0
-	}
-
-	paths := flagSet.Args()
-	if len(paths) == 0 {
-		inf, err := os.Stat("features")
-		if err == nil && inf.IsDir() {
-			paths = []string{"features"}
-		}
-	}
-
-	if concurrency > 1 && format != "progress" {
-		fatal(fmt.Errorf("when concurrency level is higher than 1, only progress format is supported"))
-	}
-	formatter, err := findFmt(format)
-	fatal(err)
-
-	features, err := parseFeatures(tags, paths)
-	fatal(err)
-
-	r := runner{
-		fmt:           formatter,
-		initializer:   contextInitializer,
-		features:      features,
-		stopOnFailure: sof,
-	}
-
-	var failed bool
-	if concurrency > 1 {
-		failed = r.concurrent(concurrency)
-	} else {
-		failed = r.run()
-	}
-	if failed {
-		return 1
-	}
-	return 0
+	return RunWithOptions(contextInitializer, opt)
 }