ABAP_to_the_Future

3
ABAP Unit and Test-Driven Development
example, but the adva ntage increases proportionally with the complexity of the
class being tested.
Note
You can also use this same methodology if the importing parameter of the object constructor
is an interface. You just pass the interface name in to the INSTEAD_OF method
rather than the main class name.
The first method called in Listing 3.22 is the DURING CONSTRUCTION method. This
is shown in Listing 3.23; it analyzes el ementary parameters and then does nothing
fancier than adding entries to an internal table.
METHOD during_construction.
* Local Variables
DATA: lo_description TYPE REF TO cl_abap_typedescr,
ld_dummy
TYPE string ##needed,
ld_data_element_name TYPE string,
ls_parameter_values LIKE LINE OF mt_parameter_values.
ls_parameter_values-identifier = for_parameter.
CREATE DATA ls_parameter_values-do_value LIKE use_value.
GET REFERENCE OF use_value INTO ls_parameter_values-do_value.
CHECK sy-subrc = 0.
CALL METHOD cl_abap_structdescr=>describe_by_data_ref
EXPORTING
p_data_ref
= ls_parameter_values-do_value
RECEIVING
p_descr_ref
= lo_description
EXCEPTIONS
reference_is_initial = 1
OTHERS = 2.
IF sy-subrc <> 0.
RETURN.
ENDIF.
SPLIT lo_description->absolute_name AT '=' INTO ld_dummy ld_data_
element_name.
ls_parameter_values-rollname = ld_data_element_name.
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