From 55a3b51e40a7d3301a114a66712c5daebae0ac6d Mon Sep 17 00:00:00 2001
From: Jasper Jenkins <jasper.vs.jenkins@gmail.com>
Date: Wed, 8 May 2019 14:29:42 -0700
Subject: [PATCH] fix complex typdesc iterators

---
 compiler/transf.nim          |  1 +
 tests/iter/titertypedesc.nim | 17 +++++++++++++++++
 2 files changed, 18 insertions(+)
 create mode 100644 tests/iter/titertypedesc.nim

diff --git a/compiler/transf.nim b/compiler/transf.nim
index 0e788b833e..c4da48d53b 100644
--- a/compiler/transf.nim
+++ b/compiler/transf.nim
@@ -560,6 +560,7 @@ type
 proc putArgInto(arg: PNode, formal: PType): TPutArgInto =
   # This analyses how to treat the mapping "formal <-> arg" in an
   # inline context.
+  if formal.kind == tyTypeDesc: return paDirectMapping
   if skipTypes(formal, abstractInst).kind in {tyOpenArray, tyVarargs}:
     if arg.kind == nkStmtListExpr:
       return paComplexOpenarray
diff --git a/tests/iter/titertypedesc.nim b/tests/iter/titertypedesc.nim
new file mode 100644
index 0000000000..a69f703c61
--- /dev/null
+++ b/tests/iter/titertypedesc.nim
@@ -0,0 +1,17 @@
+discard """
+  output: '''0
+(id: 0)
+@[]
+[0, 0, 0]'''
+"""
+
+iterator foo*(T: typedesc): T =
+  var x: T
+  yield x
+
+for a in foo(int): echo a
+for b in foo(tuple[id: int]): echo b
+for c in foo(seq[int]): echo c
+
+type Generic[T] = T
+for d in foo(Generic[array[0..2, int]]): echo d