[PATCH v2 3/6] kunit: Add macro to conditionally expose expressions to tests

[Michal Wajdeczko <michal.wajdeczko@xxxxxxxxx>]

The ONLY_IF_KUNIT macro will add expression statement only if the
CONFIG_KUNIT is enabled. Otherwise if CONFIG_KUNIT is not enabled
it will evaluate always to 0.

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@xxxxxxxxx>
---
Cc: Rae Moar <rmoar@xxxxxxxxxx>
Cc: David Gow <davidgow@xxxxxxxxxx>
Cc: Lucas De Marchi <lucas.demarchi@xxxxxxxxx>
---
 include/kunit/visibility.h | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/include/kunit/visibility.h b/include/kunit/visibility.h
index 1c23773f826c..69c71eacf368 100644
--- a/include/kunit/visibility.h
+++ b/include/kunit/visibility.h
@@ -18,6 +18,13 @@
      * @body: identifiers to be introduced conditionally
      */
     #define DECLARE_IF_KUNIT(body...)	body
+    /**
+     * ONLY_IF_KUNIT - A macro that adds expression statement only if
+     * CONFIG_KUNIT is enabled. Otherwise if CONFIG_KUNIT is not enabled
+     * it will evaluate always to 0.
+     * @expr: expression to be introduced conditionally
+     */
+    #define ONLY_IF_KUNIT(expr...)	expr
     /**
      * VISIBLE_IF_KUNIT - A macro that sets symbols to be static if
      * CONFIG_KUNIT is not enabled. Otherwise if CONFIG_KUNIT is enabled
@@ -34,6 +41,7 @@
 	    EXPORTED_FOR_KUNIT_TESTING)
 #else
     #define DECLARE_IF_KUNIT(body...)
+    #define ONLY_IF_KUNIT(expr...) 0
     #define VISIBLE_IF_KUNIT static
     #define EXPORT_SYMBOL_IF_KUNIT(symbol)
 #endif
-- 
2.43.0