1 files changed, 56 insertions, 0 deletions
diff --git a/tests/destructor/tprevent_assign2.nim b/tests/destructor/tprevent_assign2.nim
new file mode 100644
index 000000000..eb5588b1a
--- /dev/null
+++ b/tests/destructor/tprevent_assign2.nim
@@ -0,0 +1,56 @@
+discard """
+  errormsg: "'=dup' is not available for type <Foo>, which is inferred from unavailable '=copy'; requires a copy because it's not the last read of 'otherTree'; another read is done here: tprevent_assign2.nim(51, 31); routine: preventThis"
+  file: "tprevent_assign2.nim"
+  line: 49
+"""
+
+type
+  Foo = object
+    x: int
+
+proc `=destroy`(f: var Foo) = f.x = 0
+proc `=copy`(a: var Foo; b: Foo) {.error.} # = a.x = b.x
+
+proc `=sink`(a: var Foo; b: Foo) = a.x = b.x
+
+proc createTree(x: int): Foo =
+  Foo(x: x)
+
+proc take2(a, b: sink Foo) =
+  echo a.x, " ", b.x
+
+when false:
+  var otherTree: Foo
+  try:
+    for i in 0..3:
+      while true:
+        #if i == 0:
+        otherTree = createTree(44)
+        case i
+        of 0:
+          echo otherTree
+          take2(createTree(34), otherTree)
+        of 1:
+          take2(createTree(34), otherTree)
+        else:
+          discard
+  finally:
+    discard
+
+proc preventThis() =
+  var otherTree: Foo
+  for i in 0..3:
+    while true:
+      if i == 0:
+        otherTree = createTree(44)
+      case i
+      of 0:
+        echo otherTree
+        take2(createTree(34), otherTree)
+      of 1:
+        take2(createTree(34), otherTree)
+      else:
+        discard
+
+#allowThis()
+preventThis()