ABAP_to_the_Future

Behavior-Driven Development 3.5
you had gone down the long er route. The laboratory object neither knows nor
cares that what has been passed into it is not a real instance of a class but instead
a generated mock object.
Take this one step further and combine it with injection: in the injection framework
class that is part of Listing 3.27, the method INSTEAD OF has an optional
parameter via which you can pass in the generated object. You need this so that
you can enable your mockA generated instance to be used when creating the class
under test via injection. This is shown in Listing 3.28.
DATA: mo_class_under_test TYPE REF TO ycl_monster_laboratory.
… code to set up the mock object, as per above examples …
lo_monster_simulator ?= lo_mocker->generate_mockup( ).
"We want to use a test double for the database object
zcl_bc_injector=>instead_of(
using_main_class = 'YIF_MONSTER_SIMULATOR'
use_sub_class = 'YCL_MONSTER_SIMULATOR'
with_specific_instance = lo_monster_simulator ).
zcl_bc_injector=>create_via_injection(
CHANGING co_object = mo_class_under_test ).
Listing 3.28 Combining mockA with Dependency Injection
You’re passing in a generated object that will get used when the injection class
creates the class under test.
What the examples that culminate in Listing 3.28 show is that it is possible to simplify
the SETUP method dramatically when creatingthe class under test. You can use
mockA to set up test doubles with a lot less effort and injection to avoid having to
code long strings of CREATE OBJECT statements that pass the results into each other
before handing the end result into the cla ss under test when it’s finally created. The
two frameworks were not created with the intention of working together, but by
a happy accident they fit together like the pieces of a jigsaw puzzle.
3.5 Behavior-Driven Development
This chapter on test-driven development concludes by briefly introducing you to
the concept of behavior-driven development. This approach is a variation on testdriven
development, with more of a business focus; it is the idea that tests should
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