Add feedback when there are no violations found

cmd/root.go

@@ -115,6 +115,10 @@ func rootRunE(cmd *cobra.Command, args []string) error {
 		err = fmt.Errorf("files with violations: %d", violations)
 	}
 
+    if violations == 0 {
+        fmt.Println("No violations found. Stay woke \u270a")
+    }
+
 	return err
 }
 

cmd/root_test.go

@@ -1,6 +1,10 @@
 package cmd
 
 import (
+	"bytes"
+	"io"
+	"os"
+	"sync"
 	"regexp"
 	"testing"
 
@@ -25,9 +29,13 @@ func TestRunE(t *testing.T) {
 		exitOneOnFailure = false
 		noIgnore = false
 	})
-	t.Run("no violations", func(t *testing.T) {
-		err := rootRunE(new(cobra.Command), []string{"../testdata"})
-		assert.NoError(t, err)
+	t.Run("no violations found", func(t *testing.T) {
+    	got := captureOutput(func() {
+           err := rootRunE(new(cobra.Command), []string{"../testdata/good.yml"})
+           assert.NoError(t, err)
+        })
+        expected := "No violations found. Stay woke \u270a\n"
+        assert.Equal(t, expected, got)
 	})
 	t.Run("violations w error", func(t *testing.T) {
 		exitOneOnFailure = true
@@ -36,3 +44,33 @@ func TestRunE(t *testing.T) {
 		assert.Regexp(t, regexp.MustCompile(`^files with violations: \d`), err.Error())
 	})
 }
+// Returns output of `os.Stdout` as string.
+// Based on https://medium.com/@hau12a1/golang-capturing-log-println-and-fmt-println-output-770209c791b4
+func captureOutput(f func()) string {
+	reader, writer, err := os.Pipe()
+	if err != nil {
+		panic(err)
+	}
+	stdout := os.Stdout
+	stderr := os.Stderr
+	defer func() {
+		os.Stdout = stdout
+		os.Stderr = stderr
+	}()
+	os.Stdout = writer
+	os.Stderr = writer
+
+	out := make(chan string)
+	wg := new(sync.WaitGroup)
+	wg.Add(1)
+	go func() {
+		var buf bytes.Buffer
+		wg.Done()
+		_, _ = io.Copy(&buf, reader)
+		out <- buf.String()
+	}()
+	wg.Wait()
+	f()
+	writer.Close()
+	return <-out
+}