From 844f6e95837abe355e4233d033a7baa15d4a53e9 Mon Sep 17 00:00:00 2001
From: Yusuke Kuoka <ykuoka@gmail.com>
Date: Sun, 13 Nov 2022 02:48:00 +0000
Subject: [PATCH] Introduce a new test helper for easier log snapshot testing

Use the new runWithLogCapture helper instead of the long boilerplate to capture the log for snapshot testing.

Signed-off-by: Yusuke Kuoka <ykuoka@gmail.com>
---
 pkg/app/app_apply_nokubectx_test.go | 34 +++---------------------
 pkg/app/snapshot_test.go            | 41 +++++++++++++++++++++++++++++
 2 files changed, 44 insertions(+), 31 deletions(-)

diff --git a/pkg/app/app_apply_nokubectx_test.go b/pkg/app/app_apply_nokubectx_test.go
index 43d17ca2..1261e31d 100644
--- a/pkg/app/app_apply_nokubectx_test.go
+++ b/pkg/app/app_apply_nokubectx_test.go
@@ -1,14 +1,12 @@
 package app
 
 import (
-	"bufio"
-	"bytes"
-	"io"
 	"sync"
 	"testing"
 
 	"github.com/google/go-cmp/cmp"
 	"github.com/variantdev/vals"
+	"go.uber.org/zap"
 
 	"github.com/helmfile/helmfile/pkg/exectest"
 	"github.com/helmfile/helmfile/pkg/filesystem"
@@ -54,35 +52,9 @@ func TestApply_3(t *testing.T) {
 			ReleasesMutex:        &sync.Mutex{},
 		}
 
-		bs := &bytes.Buffer{}
-
-		func() {
+		bs := runWithLogCapture(t, func(t *testing.T, logger *zap.SugaredLogger) {
 			t.Helper()
 
-			logReader, logWriter := io.Pipe()
-
-			logFlushed := &sync.WaitGroup{}
-			// Ensure all the log is consumed into `bs` by calling `logWriter.Close()` followed by `logFlushed.Wait()`
-			logFlushed.Add(1)
-			go func() {
-				scanner := bufio.NewScanner(logReader)
-				for scanner.Scan() {
-					bs.Write(scanner.Bytes())
-					bs.WriteString("\n")
-				}
-				logFlushed.Done()
-			}()
-
-			defer func() {
-				// This is here to avoid data-trace on bytes buffer `bs` to capture logs
-				if err := logWriter.Close(); err != nil {
-					panic(err)
-				}
-				logFlushed.Wait()
-			}()
-
-			logger := helmexec.NewLogger(logWriter, "debug")
-
 			valsRuntime, err := vals.New(vals.Options{CacheSize: 32})
 			if err != nil {
 				t.Errorf("unexpected error creating vals runtime: %v", err)
@@ -156,7 +128,7 @@ func TestApply_3(t *testing.T) {
 					}
 				}
 			}
-		}()
+		})
 
 		if tc.log != "" {
 			actual := bs.String()
diff --git a/pkg/app/snapshot_test.go b/pkg/app/snapshot_test.go
index b36ea6e1..da42453f 100644
--- a/pkg/app/snapshot_test.go
+++ b/pkg/app/snapshot_test.go
@@ -1,15 +1,56 @@
 package app
 
 import (
+	"bufio"
+	"bytes"
+	"io"
 	"os"
 	"path/filepath"
 	"reflect"
 	"strings"
+	"sync"
 	"testing"
 
 	"github.com/google/go-cmp/cmp"
+	"go.uber.org/zap"
+
+	"github.com/helmfile/helmfile/pkg/helmexec"
 )
 
+func runWithLogCapture(t *testing.T, f func(*testing.T, *zap.SugaredLogger)) *bytes.Buffer {
+	t.Helper()
+
+	bs := &bytes.Buffer{}
+
+	logReader, logWriter := io.Pipe()
+
+	logFlushed := &sync.WaitGroup{}
+	// Ensure all the log is consumed into `bs` by calling `logWriter.Close()` followed by `logFlushed.Wait()`
+	logFlushed.Add(1)
+	go func() {
+		scanner := bufio.NewScanner(logReader)
+		for scanner.Scan() {
+			bs.Write(scanner.Bytes())
+			bs.WriteString("\n")
+		}
+		logFlushed.Done()
+	}()
+
+	defer func() {
+		// This is here to avoid data-trace on bytes buffer `bs` to capture logs
+		if err := logWriter.Close(); err != nil {
+			panic(err)
+		}
+		logFlushed.Wait()
+	}()
+
+	logger := helmexec.NewLogger(logWriter, "debug")
+
+	f(t, logger)
+
+	return bs
+}
+
 func assertLogEqualsToSnapshot(t *testing.T, data string) {
 	t.Helper()