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# bug #22619
when false: # todo fixme
block:
type
Resource = object
value: int
Object = object
r {.cursor.}: Resource
s {.cursor.}: seq[Resource]
var numDestroy = 0
proc `=copy`(x: var Resource, y: Resource) {.error.} # disallow full copies
proc `=destroy`(x: Resource) =
inc numDestroy
proc test() =
# perform the test in procedure so that globals aren't used (their different
# semantics with regards to destruction would interfere)
var
r = Resource(value: 1) # initialize a resource
s = @[Resource(value: 2)]
# make sure no copy is required in the initializer expression:
var o = Object(r: r, s: s)
# copying the object doesn't perform a full copy of the cursor fields:
var o2 = o
discard addr(o2) # prevent `o2` from being turned into a cursor
# check that the fields were shallow-copied:
doAssert o2.r.value == 1
doAssert o2.s[0].value == 2
# make sure no copy is required with normal field assignments:
o.r = r
o.s = s
# when `o` and `o2` are destroyed, their destructor must not be called on
# their fields
test()
# one call for the `r` local and one for the object in `s`
doAssert numDestroy == 2
block:
type Value = distinct int
var numDestroy = 0
when defined(gcRefc):
proc `=destroy`(x: var Value) =
inc numDestroy
else:
proc `=destroy`(x: Value) =
inc numDestroy
iterator iter(s: seq[Value]): int {.closure.} =
# because it is used across yields, `s2` is lifted into the iterator's
# environment. Since non-ref cursors in object didn't have their hooks
# disabled inside the environments lifted hooks, this led to double
# frees
var s2 {.cursor.} = s
var i = 0
let L = s2.len
while i < L:
yield s2[i].int
inc i
proc test() =
var s = @[Value(1), Value(2)]
let cl = iter
# make sure resuming the iterator works:
doAssert cl(s) == 1
doAssert cl(s) == 2
doAssert cl(s) == 0
test()
doAssert numDestroy == 2
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