Add tests for wtf/colors.go exported functions

wtf_tests/bargraph/bargraph_test.go

@@ -0,0 +1,33 @@
+package bargraph_test
+
+import (
+	"testing"
+
+	. "github.com/senorprogrammer/wtf/wtf"
+	. "github.com/stretchr/testify/assert"
+)
+
+// MakeData - Create sample data
+func makeData() [][2]int64 {
+
+	//this could come from config
+	const lineCount = 2
+	var stats [lineCount][2]int64
+
+	stats[0][1] = 1530122942000
+	stats[0][0] = 100
+
+	stats[1][1] = 1531142942000
+	stats[1][0] = 210
+
+	return stats[:]
+
+}
+
+//TestOutput of the bargraph make string (BuildStars) function
+func TestOutput(t *testing.T) {
+
+	result := BuildStars(makeData(), 20, "*")
+
+	Equal(t, "Jun 27, 2018 -\t [red]*[white] - (100)\nJul 09, 2018 -\t [red]********************[white] - (210)\n", result)
+}