/*
 * test_byref.prg — @byref pass-by-reference test
 */

STATIC s_nPass := 0
STATIC s_nFail := 0

PROCEDURE Main()

   ? "=== @byref Test Suite ==="
   ?

   TestBasicByref()
   TestChainedByref()
   TestByrefInLoop()
   TestByrefPreservesType()

   ?
   ? "Results:", hb_ntos(s_nPass), "/", hb_ntos(s_nPass + s_nFail), "passed"

RETURN


STATIC PROCEDURE TestBasicByref()
   LOCAL nVal := 10

   ModifyByRef(@nVal)
   Assert("Basic @byref: nVal changed to 42", nVal == 42)

RETURN

STATIC FUNCTION ModifyByRef(nParam)
   nParam := 42
RETURN NIL


STATIC PROCEDURE TestChainedByref()
   LOCAL nVal := 100

   MiddleMan(@nVal)
   Assert("Chained @byref: nVal changed to 999", nVal == 999)

RETURN

STATIC FUNCTION MiddleMan(x)
   InnerModify(@x)
RETURN NIL

STATIC FUNCTION InnerModify(y)
   y := 999
RETURN NIL


STATIC PROCEDURE TestByrefInLoop()
   LOCAL nSum := 0
   LOCAL i

   FOR i := 1 TO 5
      AddToByRef(@nSum, i)
   NEXT

   Assert("@byref in loop: sum 1..5 = 15", nSum == 15)

RETURN

STATIC FUNCTION AddToByRef(nAcc, nVal)
   nAcc := nAcc + nVal
RETURN NIL


STATIC PROCEDURE TestByrefPreservesType()
   LOCAL cStr := "hello"

   AppendByRef(@cStr, " world")
   Assert("@byref string: 'hello world'", cStr == "hello world")

RETURN

STATIC FUNCTION AppendByRef(cParam, cSuffix)
   cParam := cParam + cSuffix
RETURN NIL


STATIC FUNCTION Assert(cLabel, lOK)
   IF lOK
      s_nPass++
      ? "  PASS:", cLabel
   ELSE
      s_nFail++
      ? "  FAIL:", cLabel
   ENDIF
RETURN NIL