fix(dotnet): show nuget package dir not found log only when checking nuget packages (#7194)

Co-authored-by: knqyf263 <knqyf263@gmail.com>

Author: DmitriyLewen

pkg/fanal/analyzer/language/dotnet/nuget/nuget.go

@@ -17,6 +17,7 @@ import (
 	"github.com/aquasecurity/trivy/pkg/fanal/analyzer"
 	"github.com/aquasecurity/trivy/pkg/fanal/analyzer/language"
 	"github.com/aquasecurity/trivy/pkg/fanal/types"
+	"github.com/aquasecurity/trivy/pkg/log"
 	"github.com/aquasecurity/trivy/pkg/utils/fsutils"
 )
 
@@ -39,19 +40,24 @@ type nugetLibraryAnalyzer struct {
 	lockParser    language.Parser
 	configParser  language.Parser
 	licenseParser nuspecParser
+	logger        *log.Logger
 }
 
 func newNugetLibraryAnalyzer(_ analyzer.AnalyzerOptions) (analyzer.PostAnalyzer, error) {
 	return &nugetLibraryAnalyzer{
 		lockParser:    lock.NewParser(),
 		configParser:  config.NewParser(),
 		licenseParser: newNuspecParser(),
+		logger:        log.WithPrefix("nuget"),
 	}, nil
 }
 
 func (a *nugetLibraryAnalyzer) PostAnalyze(_ context.Context, input analyzer.PostAnalysisInput) (*analyzer.AnalysisResult, error) {
 	var apps []types.Application
 	foundLicenses := make(map[string][]string)
+	if a.licenseParser.packagesDir == "" {
+		a.logger.Debug("The nuget packages directory couldn't be found. License search disabled")
+	}
 
 	// We saved only config and lock files in the FS,
 	// so we need to parse all saved files

pkg/fanal/analyzer/language/dotnet/nuget/nuget_test.go

@@ -12,7 +12,7 @@ import (
 	"github.com/aquasecurity/trivy/pkg/fanal/types"
 )
 
-func Test_nugetibraryAnalyzer_Analyze(t *testing.T) {
+func Test_nugetLibraryAnalyzer_Analyze(t *testing.T) {
 	tests := []struct {
 		name string
 		dir  string

pkg/fanal/analyzer/language/dotnet/nuget/nuspec.go

@@ -9,7 +9,6 @@ import (
 
 	"golang.org/x/xerrors"
 
-	"github.com/aquasecurity/trivy/pkg/log"
 	"github.com/aquasecurity/trivy/pkg/utils/fsutils"
 )
 
@@ -30,26 +29,21 @@ type License struct {
 }
 
 type nuspecParser struct {
-	logger      *log.Logger
 	packagesDir string // global packages folder - https: //learn.microsoft.com/en-us/nuget/consume-packages/managing-the-global-packages-and-cache-folders
 }
 
 func newNuspecParser() nuspecParser {
-	logger := log.WithPrefix("nuget")
-
 	// cf. https: //learn.microsoft.com/en-us/nuget/consume-packages/managing-the-global-packages-and-cache-folders
 	packagesDir := os.Getenv("NUGET_PACKAGES")
 	if packagesDir == "" {
 		packagesDir = filepath.Join(os.Getenv("HOME"), ".nuget", "packages")
 	}
 
 	if !fsutils.DirExists(packagesDir) {
-		logger.Debug("The nuget packages directory couldn't be found. License search disabled")
 		return nuspecParser{}
 	}
 
 	return nuspecParser{
-		logger:      logger,
 		packagesDir: packagesDir,
 	}
 }