source/kernel: add unit tests for kernel version parsing

source/kernel/kernel.go

@@ -122,7 +122,7 @@ func (s *kernelSource) Discover() error {
 	s.features = nfdv1alpha1.NewFeatures()
 
 	// Read kernel version
-	if version, err := parseVersion(); err != nil {
+	if version, err := discoverVersion(); err != nil {
 		klog.ErrorS(err, "failed to get kernel version")
 	} else {
 		s.features.Attributes[VersionFeature] = nfdv1alpha1.NewAttributeFeatures(version)

source/kernel/version.go

@@ -23,17 +23,21 @@ import (
 )
 
 // Read and parse kernel version
-func parseVersion() (map[string]string, error) {
-	version := map[string]string{}
-
-	full, err := getVersion()
+func discoverVersion() (map[string]string, error) {
+	raw, err := getVersion()
 	if err != nil {
 		return nil, err
 	}
 
+	return parseVersion(raw), nil
+}
+
+func parseVersion(raw string) map[string]string {
+	version := map[string]string{}
+
 	// Replace forbidden symbols
 	fullRegex := regexp.MustCompile("[^-A-Za-z0-9_.]")
-	full = fullRegex.ReplaceAllString(full, "_")
+	full := fullRegex.ReplaceAllString(raw, "_")
 	// Label values must start and end with an alphanumeric
 	full = strings.Trim(full, "-_.")
 
@@ -49,7 +53,7 @@ func parseVersion() (map[string]string, error) {
 		}
 	}
 
-	return version, nil
+	return version
 }
 
 func getVersion() (string, error) {

source/kernel/version_test.go

@@ -0,0 +1,72 @@
+/*
+Copyright 2024 The Kubernetes 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 kernel
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestParseVersion(t *testing.T) {
+	tests := []struct {
+		raw      string
+		expected map[string]string
+	}{
+		{
+			raw: "6.2.3",
+			expected: map[string]string{
+				"full":     "6.2.3",
+				"major":    "6",
+				"minor":    "2",
+				"revision": "3",
+			},
+		},
+		{
+			raw: "6.0.0-beta",
+			expected: map[string]string{
+				"full":     "6.0.0-beta",
+				"major":    "6",
+				"minor":    "0",
+				"revision": "0",
+			},
+		},
+		{
+			raw: "6.8",
+			expected: map[string]string{
+				"full":     "6.8",
+				"major":    "6",
+				"minor":    "8",
+				"revision": "",
+			},
+		},
+		{
+			raw: "6.0.10-100+123.x86_64~",
+			expected: map[string]string{
+				"full":     "6.0.10-100_123.x86_64",
+				"major":    "6",
+				"minor":    "0",
+				"revision": "10",
+			},
+		},
+	}
+
+	for _, test := range tests {
+		actual := parseVersion(test.raw)
+		assert.Equal(t, test.expected, actual)
+	}
+}