fix: follow newline conventions of the autofixed file

This change makes the autofix handler use the newline separator defined
in the fixed file for writing its changes.

core/pkg/fixhandler/datastructures.go

@@ -1,6 +1,9 @@
 package fixhandler
 
 import (
+	"sort"
+	"strings"
+
 	"github.com/armosec/armoapi-go/armotypes"
 	metav1 "github.com/kubescape/kubescape/v2/core/meta/datastructures/v1"
 	"github.com/kubescape/opa-utils/reporthandling"
@@ -43,7 +46,7 @@ type fixInfoMetadata struct {
 	linesToRemove       *[]linesToRemove
 }
 
-// ContentToAdd holds the information about where to insert the new changes in the existing yaml file
+// contentToAdd holds the information about where to insert the new changes in the existing yaml file
 type contentToAdd struct {
 	// Line where the fix should be applied to
 	line int
@@ -51,6 +54,49 @@ type contentToAdd struct {
 	content string
 }
 
+func withNewline(content, targetNewline string) string {
+	replaceNewlines := map[string]bool{
+		unixNewline:    true,
+		windowsNewline: true,
+		oldMacNewline:     true,
+	}
+	replaceNewlines[targetNewline] = false
+
+	newlinesToReplace := make([]string, len(replaceNewlines))
+	i := 0
+	for k := range replaceNewlines {
+		newlinesToReplace[i] = k
+		i++
+	}
+
+	// To ensure that we fully replace Windows newlines (CR LF), and not
+	// corrupt them into two new newlines (CR CR or LF LF) by partially
+	// replacing either CR or LF, we have to ensure we replace longer
+	// Windows newlines first
+	sort.Slice(newlinesToReplace, func(i int, j int) bool {
+		return len(newlinesToReplace[i]) > len(newlinesToReplace[j])
+	})
+
+	// strings.Replacer takes a flat list of (oldVal, newVal) pairs, so we
+	// need to allocate twice the space and assign accordingly
+	newlinesOldNew := make([]string, 2*len(replaceNewlines))
+	i = 0
+	for _, nl := range newlinesToReplace {
+		newlinesOldNew[2*i] = nl
+		newlinesOldNew[2*i+1] = targetNewline
+		i++
+	}
+
+	replacer := strings.NewReplacer(newlinesOldNew...)
+	return replacer.Replace(content)
+}
+
+// Content returns the content that will be added, separated by the explicitly
+// provided `targetNewline`
+func (c *contentToAdd) Content(targetNewline string) string {
+	return withNewline(c.content, targetNewline)
+}
+
 // LinesToRemove holds the line numbers to remove from the existing yaml file
 type linesToRemove struct {
 	startLine int

core/pkg/fixhandler/datastructures_test.go

@@ -0,0 +1,89 @@
+package fixhandler
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestContentNewlinesMatchTarget(t *testing.T) {
+	cases := []struct {
+		Name          string
+		InputContent  string
+		TargetNewline string
+		WantedContent string
+	}{
+		{
+			"Unix to DOS",
+			"first line\nsecond line\n",
+			"\r\n",
+			"first line\r\nsecond line\r\n",
+		},
+		{
+			"Unix to Unix",
+			"first line\nsecond line\n",
+			"\n",
+			"first line\nsecond line\n",
+		},
+		{
+			"Unix to Mac",
+			"first line\nsecond line\n",
+			"\r",
+			"first line\rsecond line\r",
+		},
+		{
+			"DOS to Unix",
+			"first line\r\nsecond line\r\n",
+			"\n",
+			"first line\nsecond line\n",
+		},
+		{
+			"DOS to DOS",
+			"first line\r\nsecond line\r\n",
+			"\r\n",
+			"first line\r\nsecond line\r\n",
+		},
+		{
+			"DOS to OldMac",
+			"first line\r\nsecond line\r\n",
+			"\r",
+			"first line\rsecond line\r",
+		},
+		{
+			"Mac to DOS",
+			"first line\rsecond line\r",
+			"\r\n",
+			"first line\r\nsecond line\r\n",
+		},
+		{
+			"Mac to Unix",
+			"first line\rsecond line\r",
+			"\n",
+			"first line\nsecond line\n",
+		},
+		{
+			"DOS, Mac to Unix",
+			"first line\r\n\rsecond line\r",
+			"\n",
+			"first line\n\nsecond line\n",
+		},
+		{
+			"Mac, DOS to Unix",
+			"first line\r\r\r\nsecond line\r",
+			"\n",
+			"first line\n\n\nsecond line\n",
+		},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.Name, func(t *testing.T) {
+			c := &contentToAdd{content: tc.InputContent}
+			want := tc.WantedContent
+
+			got := c.Content(tc.TargetNewline)
+
+			assert.Equal(t, want, got)
+		})
+	}
+
+}

core/pkg/fixhandler/fixhandler.go

@@ -24,6 +24,10 @@ import (
 
 const UserValuePrefix = "YOUR_"
 
+const windowsNewline = "\r\n"
+const unixNewline = "\n"
+const oldMacNewline = "\r"
+
 func NewFixHandler(fixInfo *metav1.FixInfo) (*FixHandler, error) {
 	jsonFile, err := os.Open(fixInfo.ReportFile)
 	if err != nil {
@@ -232,7 +236,9 @@ func (h *FixHandler) getFilePathAndIndex(filePathWithIndex string) (filePath str
 }
 
 func (h *FixHandler) ApplyFixToContent(yamlAsString, yamlExpression string) (fixedString string, err error) {
-	yamlLines := strings.Split(yamlAsString, "\n")
+	newline := determineNewlineSeparator(yamlAsString)
+
+	yamlLines := strings.Split(yamlAsString, newline)
 
 	originalRootNodes, err := decodeDocumentRoots(yamlAsString)
 
@@ -248,9 +254,9 @@ func (h *FixHandler) ApplyFixToContent(yamlAsString, yamlExpression string) (fix
 
 	fileFixInfo := getFixInfo(originalRootNodes, fixedRootNodes)
 
-	fixedYamlLines := getFixedYamlLines(yamlLines, fileFixInfo)
+	fixedYamlLines := getFixedYamlLines(yamlLines, fileFixInfo, newline)
 
-	fixedString = getStringFromSlice(fixedYamlLines)
+	fixedString = getStringFromSlice(fixedYamlLines, newline)
 
 	return fixedString, nil
 }
@@ -344,3 +350,12 @@ func writeFixesToFile(filepath, content string) error {
 
 	return nil
 }
+
+func determineNewlineSeparator(contents string) string {
+	switch {
+	case strings.Contains(contents, windowsNewline):
+		return windowsNewline
+	default:
+		return unixNewline
+	}
+}

core/pkg/fixhandler/fixhandler_test.go

@@ -98,6 +98,11 @@ func getTestCases() []indentationTestCase {
 			`select(di==0).spec.containers += {"name": "redis", "image": "redis"}`,
 			"inserts/tc-10-01-expected.yaml",
 		},
+		{
+			"inserts/tc-11-00-input-list-insert-new-mapping-crlf-newlines.yaml",
+			`select(di==0).spec.containers += {"name": "redis", "image": "redis"}`,
+			"inserts/tc-11-01-expected.yaml",
+		},
 
 		// Removal Scenarios
 		{

core/pkg/fixhandler/testdata/inserts/tc-11-00-input-list-insert-new-mapping-crlf-newlines.yaml

@@ -0,0 +1,11 @@
+# Fix to Apply:
+# select(di==0).spec.containers += {"name": "redis", "image": "redis"}
+
+apiVersion: v1
+kind: Pod
+metadata:
+  name: indented-list-insert-new-object
+spec:
+  containers:
+  - name: nginx_container
+    image: nginx

core/pkg/fixhandler/testdata/inserts/tc-11-01-expected.yaml

@@ -0,0 +1,13 @@
+# Fix to Apply:
+# select(di==0).spec.containers += {"name": "redis", "image": "redis"}
+
+apiVersion: v1
+kind: Pod
+metadata:
+  name: indented-list-insert-new-object
+spec:
+  containers:
+  - name: nginx_container
+    image: nginx
+  - name: redis
+    image: redis

core/pkg/fixhandler/yamlhandler.go

@@ -244,7 +244,7 @@ func removeNewLinesAtTheEnd(yamlLines []string) []string {
 	return yamlLines
 }
 
-func getFixedYamlLines(yamlLines []string, fileFixInfo fileFixInfo) (fixedYamlLines []string) {
+func getFixedYamlLines(yamlLines []string, fileFixInfo fileFixInfo, newline string) (fixedYamlLines []string) {
 
 	// Determining last line requires original yaml lines slice. The placeholder for last line is replaced with the real last line
 	assignLastLine(fileFixInfo.contentsToAdd, fileFixInfo.linesToRemove, &yamlLines)
@@ -267,7 +267,7 @@ func getFixedYamlLines(yamlLines []string, fileFixInfo fileFixInfo) (fixedYamlLi
 			lineIdx += 1
 		}
 
-		content := (*fileFixInfo.contentsToAdd)[lineToAddIdx].content
+		content := (*fileFixInfo.contentsToAdd)[lineToAddIdx].Content(newline)
 		fixedYamlLines = append(fixedYamlLines, content)
 
 		lineToAddIdx += 1

core/pkg/fixhandler/yamlhelper.go

@@ -401,6 +401,6 @@ func updateTracker(nodeList *[]nodeInfo, tracker int) int {
 	return updatedTracker
 }
 
-func getStringFromSlice(yamlLines []string) (fixedYamlString string) {
-	return strings.Join(yamlLines, "\n")
+func getStringFromSlice(yamlLines []string, newline string) (fixedYamlString string) {
+	return strings.Join(yamlLines, newline)
 }