Avoid CASE with a Single WHEN Branch

WarningAnti-Patterns & Bad Practices#EC SINGLE_WHENRemote Enabled

Overview

Avoid CASE statements with only one WHEN branch.

ATC Finding Message: CASE statement has <= 1 WHEN branch; prefer IF

Rationale

CASE implies that a value is compared against several alternatives, so a single WHEN makes readers look for missing branches. An IF with the same condition is shorter and states the intent directly. Use CASE only when there are multiple distinct branches or when a value mapping is genuinely clearer.

Non-Compliant

CASE lv_order_status.
  WHEN 'C'.
    close_order( ).
ENDCASE.

Compliant

IF lv_order_status = 'C'.
  close_order( ).
ENDIF.

Suppression

To suppress findings for this rule, append the pseudo-comment to the statement:

" Standard pseudo-comment:
... "#EC SINGLE_WHEN

" SAP CI_ prefix format:
... "#EC CI_SINGLE_WHEN

Technical Details

• Native ATC Class: ZCL_SKYLINT_NO_SINGLE_WHEN
• Implementation File: zcl_skylint_no_single_when.clas.abap