diff --git a/engine/account_test.go b/engine/account_test.go
index 3d0aafd74..68711fe84 100644
--- a/engine/account_test.go
+++ b/engine/account_test.go
@@ -3335,10 +3335,91 @@ func TestEngineToStringJSON(t *testing.T) {
 	}
 	want, err := json.Marshal(acc)
 	if err != nil {
-		t.Errorf("Error marshalling Account to JSON: %v", err)
+		t.Error(err)
 	}
 	got := acc.String()
 	if got != string(want) {
-		t.Errorf("Expected JSON: %s, got: %s", want, got)
+		t.Errorf("acc.String()=%s, want%s", got, want)
+	}
+}
+
+func TestEngineGetID(t *testing.T) {
+	tests := []struct {
+		name  string
+		accID string
+		want  string
+	}{
+		{
+			name:  "Valid ID format",
+			accID: "prefix" + utils.ConcatenatedKeySep + "suffix",
+			want:  "suffix",
+		},
+		{
+			name:  "Invalid ID format (missing separator)",
+			accID: "invalidID",
+			want:  "",
+		},
+		{
+			name:  "Invalid ID format (too many parts)",
+			accID: "prefix" + utils.ConcatenatedKeySep + "suffix" + utils.ConcatenatedKeySep + "extra",
+			want:  "",
+		},
+		{
+			name:  "Empty ID",
+			accID: "",
+			want:  "",
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			acc := &Account{ID: tt.accID}
+			got := acc.GetID()
+			if got != tt.want {
+				t.Errorf("Expected ID: %s, Got: %s", tt.want, got)
+			}
+		})
+	}
+}
+
+func TestEngineNewAccountSummaryFromJSON(t *testing.T) {
+	tests := []struct {
+		name    string
+		jsonStr string
+		want    *AccountSummary
+	}{
+		{
+			name:    "Valid JSON",
+			jsonStr: `{"tenant": "cgrates.org", "id": "1234", "balanceSummaries": [], "allowNegative": false, "disabled": true}`,
+			want: &AccountSummary{
+				Tenant:           "cgrates.org",
+				ID:               "1234",
+				BalanceSummaries: BalanceSummaries{},
+				AllowNegative:    false,
+				Disabled:         true,
+			},
+		},
+		{
+			name:    "Empty JSON",
+			jsonStr: "",
+			want:    nil,
+		},
+		{
+			name:    "Null JSON",
+			jsonStr: "null",
+			want:    nil,
+		},
+		{
+			name:    "Invalid JSON",
+			jsonStr: "{invalid: json}",
+			want:    nil,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, _ := NewAccountSummaryFromJSON(tt.jsonStr)
+			if !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("NewAccountSummaryFromJSON(%q) got = %v, want %v", tt.jsonStr, got, tt.want)
+			}
+		})
 	}
 }
diff --git a/engine/ratingprofile_test.go b/engine/ratingprofile_test.go
index 5993689cb..67e98a3db 100644
--- a/engine/ratingprofile_test.go
+++ b/engine/ratingprofile_test.go
@@ -18,12 +18,12 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>
 package engine
 
 import (
-	"reflect"
 	"testing"
 	"time"
 
 	"github.com/cgrates/cgrates/config"
 	"github.com/cgrates/cgrates/utils"
+	"github.com/google/go-cmp/cmp"
 )
 
 func TestGetRatingProfileForPrefix(t *testing.T) {
@@ -479,14 +479,13 @@ func TestEngineSwapRpasIndex(t *testing.T) {
 		FallbackKeys:   []string{"key3"},
 	}
 	initialRPAs := RatingPlanActivations{plan1, plan2}
-	index1 := 0
-	index2 := 1
 	want := RatingPlanActivations{plan2, plan1}
 	rpas := make(RatingPlanActivations, len(initialRPAs))
 	copy(rpas, initialRPAs)
-	rpas.Swap(index1, index2)
-	if !reflect.DeepEqual(rpas, want) {
-		t.Errorf("Expected RatingPlanActivations after swap: %v, got: %v", want, rpas)
+	rpas.Swap(0, 1)
+	diff := cmp.Diff(rpas, want)
+	if diff != "" {
+		t.Errorf("Expected RatingPlanActivations after swap to be equal to want: (-got, +want)\n%s", diff)
 	}
 }
 
diff --git a/engine/units_counter_test.go b/engine/units_counter_test.go
index dccf07e11..5bfefaea1 100644
--- a/engine/units_counter_test.go
+++ b/engine/units_counter_test.go
@@ -957,7 +957,7 @@ func TestEngineCounterFilterString(t *testing.T) {
 	}
 	want, err := json.Marshal(testFilter)
 	if err != nil {
-		t.Errorf("Error marshalling CounterFilter to JSON: %v", err)
+		t.Error(err)
 	}
 	got := testFilter.String()
 	if got != string(want) {
@@ -971,7 +971,7 @@ func TestEngineUnitCounterString(t *testing.T) {
 	}
 	want, err := json.Marshal(testCounter)
 	if err != nil {
-		t.Errorf("Error marshalling UnitCounter to JSON: %v", err)
+		t.Error(err)
 	}
 	got := testCounter.String()
 	if got != string(want) {