Add tests for logging LogHolder

Signed-off-by: Evans Mungai <mbuevans@gmail.com>

internal/logging/logging_test.go

@@ -0,0 +1,115 @@
+/*
+Copyright The Helm Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package logging
+
+import (
+	"bytes"
+	"log/slog"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestLogHolder_Logger(t *testing.T) {
+	t.Run("should return new logger with a then set handler", func(t *testing.T) {
+		holder := &LogHolder{}
+		buf := &bytes.Buffer{}
+		handler := slog.NewTextHandler(buf, &slog.HandlerOptions{Level: slog.LevelDebug})
+
+		holder.SetLogger(handler)
+		logger := holder.Logger()
+
+		assert.NotNil(t, logger)
+
+		// Test that the logger works
+		logger.Info("test message")
+		assert.Contains(t, buf.String(), "test message")
+	})
+
+	t.Run("should return discard - defaultlogger when no handler is set", func(t *testing.T) {
+		holder := &LogHolder{}
+		logger := holder.Logger()
+
+		assert.Equal(t, slog.Default().Handler(), logger.Handler())
+	})
+}
+
+func TestLogHolder_SetLogger(t *testing.T) {
+	t.Run("sets logger with valid handler", func(t *testing.T) {
+		holder := &LogHolder{}
+		buf := &bytes.Buffer{}
+		handler := slog.NewTextHandler(buf, &slog.HandlerOptions{Level: slog.LevelDebug})
+
+		holder.SetLogger(handler)
+		logger := holder.Logger()
+
+		assert.NotNil(t, logger)
+
+		// Compare the handler directly
+		assert.Equal(t, handler, logger.Handler())
+	})
+
+	t.Run("sets discard logger with nil handler", func(t *testing.T) {
+		holder := &LogHolder{}
+
+		holder.SetLogger(nil)
+		logger := holder.Logger()
+
+		assert.NotNil(t, logger)
+
+		assert.Equal(t, slog.Handler(slog.DiscardHandler), logger.Handler())
+	})
+
+	t.Run("can replace existing logger", func(t *testing.T) {
+		holder := &LogHolder{}
+
+		// Set first logger
+		buf1 := &bytes.Buffer{}
+		handler1 := slog.NewTextHandler(buf1, &slog.HandlerOptions{Level: slog.LevelDebug})
+		holder.SetLogger(handler1)
+
+		logger1 := holder.Logger()
+		assert.Equal(t, handler1, logger1.Handler())
+
+		// Replace with second logger
+		buf2 := &bytes.Buffer{}
+		handler2 := slog.NewTextHandler(buf2, &slog.HandlerOptions{Level: slog.LevelDebug})
+		holder.SetLogger(handler2)
+
+		logger2 := holder.Logger()
+		assert.Equal(t, handler2, logger2.Handler())
+	})
+}
+
+func TestLogHolder_InterfaceCompliance(t *testing.T) {
+	t.Run("implements LoggerSetterGetter interface", func(_ *testing.T) {
+		var _ LoggerSetterGetter = &LogHolder{}
+	})
+
+	t.Run("interface methods work correctly", func(t *testing.T) {
+		var holder LoggerSetterGetter = &LogHolder{}
+
+		buf := &bytes.Buffer{}
+		handler := slog.NewTextHandler(buf, &slog.HandlerOptions{Level: slog.LevelDebug})
+
+		holder.SetLogger(handler)
+		logger := holder.Logger()
+
+		assert.NotNil(t, logger)
+		assert.Equal(t, handler, logger.Handler())
+	})
+}