Add JsonSprintError

json.go

@@ -6,7 +6,7 @@ import (
 	"encoding/json"
 )
 
-func JsonPrintError(err error, content []byte) {
+func JsonSprintError(err error, content []byte) (error, string) {
 	if syntaxErr, ok := err.(*json.SyntaxError); ok {
 		totalLen := int64(len(content))
 		
@@ -16,11 +16,18 @@ func JsonPrintError(err error, content []byte) {
 		to := MathMin(syntaxErr.Offset + min, totalLen)
 
 		sliceBuf := content[from:to]
-		
-		log.Printf("Failed to unmarshal %#v \n %s", syntaxErr, string(sliceBuf))
+
+		return err, string(sliceBuf)
 	} else {
-		log.Printf("%v", err)
+		
+		return err, ""
 	}
+}
+
+func JsonPrintError(err error, content []byte) {
+	e, s := JsonSprintError(err, content)
+	
+	log.Printf("Failed to unmarshal %#v \n %s", e, s)
 } 
 
 // JsonEqual check if two json string representations are equal.

json_test.go

@@ -39,3 +39,30 @@ func TestJsonPrintError(t *testing.T) {
 	}
 } 
 
+func TestJsonSprintError(t *testing.T) {
+	jsonstr := `
+	{
+		"name": "George",
+		"age": 87,
+		active": "false",
+		"properties": {
+			"one": "two",
+			"three": "four"
+		}
+	}
+	`
+
+	var buf bytes.Buffer
+	log.SetOutput(&buf)
+
+	content := []byte(jsonstr)
+	var data map[string]any
+	
+	err := json.Unmarshal(content, &data)
+
+	_, s := JsonSprintError(err, content)
+
+	if s == "" {
+		t.Fatal("should have printed the error")
+	}
+}