template: preserve quoted numeric strings in DeepCopyWithTemplate

template/template.go

@@ -463,10 +463,16 @@ func DeepCopyWithTemplate(value any, tmplTextFunc TemplateFunc) (any, error) {
 		if ok == nil {
 			var inlineType any
 			err := yaml.Unmarshal([]byte(parsed), &inlineType)
-			if err != nil || (inlineType != nil && reflect.TypeOf(inlineType).Kind() == reflect.String) {
+			if err != nil {
 				// ignore error, thus the string is not an interface
 				return parsed, ok
 			}
+			if inlineString, isString := inlineType.(string); isString {
+				return inlineString, ok
+			}
+			if strings.TrimSpace(parsed) == "" {
+				return parsed, ok
+			}
 			return DeepCopyWithTemplate(inlineType, tmplTextFunc)
 		}
 		return parsed, ok

template/template_test.go

@@ -693,6 +693,33 @@ func TestDeepCopyWithTemplate(t *testing.T) {
 			fn:    withSuffix,
 			want:  "hello-templated",
 		},
+		{
+			title: "quoted numeric string stays string",
+			input: "hello",
+			fn: TemplateFunc(func(string) (string, error) {
+				return "\"123\"", nil
+			}),
+			want: "123",
+		},
+		{
+			title: "quoted numeric string stays string in nested map",
+			input: map[string]any{
+				"customfield_11209": map[string]any{
+					"id": "TOKEN",
+				},
+			},
+			fn: TemplateFunc(func(s string) (string, error) {
+				if s == "TOKEN" {
+					return "\"15129\"", nil
+				}
+				return s, nil
+			}),
+			want: map[string]any{
+				"customfield_11209": map[string]any{
+					"id": "15129",
+				},
+			},
+		},
 		{
 			title: "string parsed as YAML map",
 			input: "foo: bar",