If you ever get "Error executing code: The field with ID '0' does not exist in table 'SysExtensionSerializerExtensionMap'." error in CIL, it may happen it is the table extension framework + the standard buf2buf function to blame.
Somehow, if you pass a Map instead of a table to buf2buf function, the following line fails:
_to.(fieldId) = _from.(fieldId);
However, if you replace this line with:
fieldName = fieldId2name(_from.TableId, fieldId);
_to.setFieldValue(fieldName, _from.getFieldValue(fieldName));
everything is fine both in X++ and in CIL.
P.S. I didn't dare to change the standard buf2buf method. Istead, I created another method and used it in the table extension framework logic, which failed because of the issue (\Data Dictionary\Maps\SysExtensionSerializerMap\Methods\copyExtensionTableData)
Somehow, if you pass a Map instead of a table to buf2buf function, the following line fails:
_to.(fieldId) = _from.(fieldId);
However, if you replace this line with:
fieldName = fieldId2name(_from.TableId, fieldId);
_to.setFieldValue(fieldName, _from.getFieldValue(fieldName));
everything is fine both in X++ and in CIL.
P.S. I didn't dare to change the standard buf2buf method. Istead, I created another method and used it in the table extension framework logic, which failed because of the issue (\Data Dictionary\Maps\SysExtensionSerializerMap\Methods\copyExtensionTableData)