feat: Adding Savetofile() and its test

pkg/iniparser.go

@@ -5,6 +5,7 @@ import (
 	"log"
 	"os"
 	"reflect"
+	"sort"
 	"strings"
 )
 
@@ -103,11 +104,37 @@ func (i *iniParser) Set(sectionName string, key string, value string) error {
 
 func (i *iniParser) ToString() string {
 	var result string
-	for sectionName, section := range i.sections {
+	sectionNames := make([]string, 0)
+	for sectionName := range i.sections {
+		sectionNames = append(sectionNames, sectionName)
+	}
+	sort.Strings(sectionNames)
+
+	for _, sectionName := range sectionNames {
+		keys := make([]string, 0)
 		result += "[" + sectionName + "]\n"
-		for key, value := range section.map_ {
-			result += key + "=" + value + "\n"
+		for key := range i.sections[sectionName].map_ {
+			keys = append(keys, key)
+		}
+		sort.Strings(keys)
+		for _, key := range keys {
+			result += key + " = " + i.sections[sectionName].map_[key] + "\n"
 		}
 	}
 	return result
 }
+
+func (i *iniParser) SaveToFile(path string) error {
+	file, err := os.OpenFile(path, os.O_CREATE|os.O_WRONLY, 0644)
+	if err != nil {
+		return fmt.Errorf("error in opening the file: %v", err)
+	}
+	defer file.Close()
+
+	stringFile := i.ToString()
+	_, err = file.WriteString(stringFile)
+	if err != nil {
+		return fmt.Errorf("error in writing to the file: %v", err)
+	}
+	return nil
+}

pkg/iniparser_test.go

@@ -2,6 +2,7 @@ package iniparser
 
 import (
 	"fmt"
+	"os"
 	"reflect"
 	"testing"
 )
@@ -16,7 +17,10 @@ organization = Acme Widgets Inc.
 [database]
 ; use IP address in case network name resolution is not working
 server = 192.0.2.62
-port = 143`
+port = 143
+[section]
+key0 = val0    
+key1 = val1`
 
 func populateExpectedNormal(t *testing.T) map[string]section {
 	t.Helper()
@@ -33,6 +37,12 @@ func populateExpectedNormal(t *testing.T) map[string]section {
 				"port":   "143",
 			},
 		},
+		"section": {
+			map_: map[string]string{
+				"key0": "val0",
+				"key1": "val1",
+			},
+		},
 	}
 	return expected
 }
@@ -63,6 +73,16 @@ func assertEquality(t *testing.T, obj1 any, obj2 any) {
 	}
 }
 
+func assertFile(t *testing.T, filePath string, expectedData string) {
+	t.Helper()
+	data, err := os.ReadFile(filePath)
+	if err != nil {
+		t.Errorf("Error! : %v\n", err)
+	}
+	assertEquality(t, expectedData, string(data))
+
+}
+
 func TestLoadFromString(t *testing.T) {
 	t.Run("test normal ini file", func(t *testing.T) {
 
@@ -106,7 +126,7 @@ func TestGetSectionNames(t *testing.T) {
 	parser.LoadFromFile(path)
 	names := parser.GetSectionNames()
 
-	expected := []string{"owner", "database"}
+	expected := []string{"owner", "database", "section"}
 
 	assertEquality(t, expected, names)
 }
@@ -222,3 +242,14 @@ func TestToString(t *testing.T) {
 
 	assertEquality(t, parser1.sections, parser2.sections)
 }
+
+func TestSaveToFile(t *testing.T) {
+	const outPath = "testdata/out.ini"
+	parser := InitParser()
+	parser.LoadFromFile(path)
+
+	parser.SaveToFile(outPath)
+
+	stringFile := parser.ToString()
+	assertFile(t, outPath, stringFile)
+}

pkg/testdata/file.ini

@@ -6,3 +6,6 @@ organization = Acme Widgets Inc.
 [database]
 server = 192.0.2.62     
 port = 143
+[section]
+key0 = val0    
+key1 = val1

pkg/testdata/out.ini

@@ -0,0 +1,9 @@
+[database]
+port = 143
+server = 192.0.2.62
+[owner]
+name = John Doe
+organization = Acme Widgets Inc.
+[section]
+key0 = val0
+key1 = val1