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Other versions: 7.31 | 7.40 | 7.54




The statement TEST-INJECTION introduces an injection for a test seam seam, closed using END-TEST-INJECTION. The test seam seam must be defined in the production code of the current program using the statement TEST-SEAM. When a unit test is performed, the statement block statement_block of the injection replaces the statement block of the test seam seam in production code.

An injection can only be defined in those methods of test classes created in a test include. Injections have the following properties:

  • Injections can be made only while a test method or the setup method is being executed.
  • Injections cannot be nested, which means that an injection cannot contain further injections.
  • An injection cannot extend beyond the limits of a statement block, but can contain closed control structures.
  • An injection can include local data declarations using the statement DATA. These variables are visible below their declaration in the current injection and all following injections of the current test class. The data objects declared in an injection are not visible outside of injections (in other parts of the test class or in production code). Injections that access data objects declared in a different injection can only be assigned to test seams defined in the production source code below the test seam (meaning the test seam assigned to the declaring injection).
  • An injection can be empty (that is, it is does not contain any statements). The code of the specified test seam is removed when the injection is executed.
  • Injections can access all types and objects that are visible in the location of the specified test seam.
  • In an injection, it is not possible to access types and objects of the test method, which the injection is defined in. These types and objects are placed in the location of the statement TEST-INJECTION, but are not visible in the injection.

The test seam remains replaced by the injection until the test seam encounters a new injection. This means that a test seam can be replaced more than once during a unit test and by different injections. All replacements are canceled at the end of a individual test or test method.


  • When the test runs, any data objects declared in injections are preserved in their context, even if the declaring injection is replaced by a different injection in its test seam.
  • Apart from DATA, no declarative statements are possible in injections.
  • Test includes can currently only be created for class pools and functions groups; this means that injections can only be created there as well.


The test include of the class CL_DEMO_TEST_SEAMS is an example of a test class with injections:

The test method tests the method CHANGE_PRICE (see the example for TEST-SEAM). Before the test method runs, the injection replaces the injection in the setup method of the test seam selection. When the test method runs,

  • the statements of the test seam modification are removed when replaced by an empty injection and the successful closing of the method is confirmed,
  • the statements of the test seam modification are replaced in such a way that an unsuccessful modification of the table content is simulated, and the associated return code checked,
  • the statements of the test seam selection are replaced in such a way that an unsuccessful selection of the table content is simulated, and the associated return code checked.
                          RISK LEVEL HARMLESS
                          DURATION SHORT
    METHODS: setup,
      test_change_price FOR TESTING,
      invoke_and_assert IMPORTING exp TYPE i.

CLASS test_demo_test_seam IMPLEMENTATION.
  METHOD setup.
    TEST-INJECTION selection.
      wa-price = 100.
  METHOD test_change_price.
    TEST-INJECTION modification.
    invoke_and_assert( 90 ).
    TEST-INJECTION modification.
      sy-subrc = 4.
    invoke_and_assert( -2 ).
    TEST-INJECTION selection.
      sy-subrc = 4.
    TEST-INJECTION modification.
    invoke_and_assert( -1 ).
  METHOD invoke_and_assert.
    NEW cl_demo_test_seams( )->change_price(
         carrid = '   '
         connid = '0000'
         fldate = '00000000'
         factor = 90
       IMPORTING new_price = DATA(new_price) ).
       exp                  = exp
       act = new_price  ).