Merge pull request #11 from msgehard/demo-without-login

`exercism demo` should not require login

src/exercism/config.go

@@ -4,6 +4,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"io/ioutil"
+	"os"
 )
 
 const FILENAME = ".exercism.go"
@@ -40,6 +41,15 @@ func ConfigToFile(dir string, c Config) (err error) {
 	return
 }
 
+func DemoDirectory() (dir string, err error) {
+	dir, err = os.Getwd()
+	if err != nil {
+		return
+	}
+	dir = dir + "/exercism-demo"
+	return
+}
+
 func configFilename(dir string) string {
 	return dir + "/" + FILENAME
 }

src/exercism/config_test.go

@@ -3,6 +3,8 @@ package exercism
 import (
 	"github.com/stretchr/testify/assert"
 	"io/ioutil"
+	"os"
+	"path/filepath"
 	"testing"
 )
 
@@ -23,3 +25,17 @@ func TestReadingWritingConfig(t *testing.T) {
 
 	assert.Equal(t, writtenConfig, loadedConfig)
 }
+
+func TestDemoDir(t *testing.T) {
+	path, err := ioutil.TempDir("", "")
+	assert.NoError(t, err)
+	os.Chdir(path)
+
+	path, err = filepath.EvalSymlinks(path)
+	assert.NoError(t, err)
+
+	path = filepath.Join(path, "exercism-demo")
+
+	demoDir, err := DemoDirectory()
+	assert.Equal(t, demoDir, path)
+}

src/main/exercism.go

@@ -23,8 +23,17 @@ func main() {
 			Action: func(c *cli.Context) {
 				config, err := exercism.ConfigFromFile(exercism.HomeDir())
 				if err != nil {
-					fmt.Println("Are you sure you are logged in? Please login again.")
-					return
+					demoDir, err2 := exercism.DemoDirectory()
+					if err2 != nil {
+						err = err2
+						fmt.Println(err)
+						return
+					}
+					config = exercism.Config{
+						Hostname: "http://exercism.io",
+						ApiKey: "",
+						ExercismDirectory: demoDir,
+					}
 				}
 				assignments, err := exercism.FetchAssignments(config.Hostname,
 					exercism.FetchEndpoints["demo"], config.ApiKey)