From 6e4ea40475095a74c40f94b0d01e4d878661720f Mon Sep 17 00:00:00 2001
From: Jasper Jenkins <jasper.vs.jenkins@gmail.com>
Date: Sat, 4 May 2019 14:28:09 -0700
Subject: [PATCH] empty container param error msg (#11158)

---
 compiler/semtypes.nim            | 3 +++
 tests/errmsgs/temptysetparam.nim | 5 +++++
 2 files changed, 8 insertions(+)
 create mode 100644 tests/errmsgs/temptysetparam.nim

diff --git a/compiler/semtypes.nim b/compiler/semtypes.nim
index bd64af729b..99fd625504 100644
--- a/compiler/semtypes.nim
+++ b/compiler/semtypes.nim
@@ -1133,6 +1133,9 @@ proc semProcTypeNode(c: PContext, n, genericParams: PNode,
 
       if typ == nil:
         typ = def.typ
+        if isEmptyContainer(typ):
+          localError(c.config, a.info, "cannot infer the type of parameter '" & a[0].ident.s & "'")
+
         if typ.kind == tyTypeDesc:
           # consider a proc such as:
           # proc takesType(T = int)
diff --git a/tests/errmsgs/temptysetparam.nim b/tests/errmsgs/temptysetparam.nim
new file mode 100644
index 0000000000..20763fedab
--- /dev/null
+++ b/tests/errmsgs/temptysetparam.nim
@@ -0,0 +1,5 @@
+discard """
+  errormsg: "cannot infer the type of parameter 'x'"
+  line: 5
+"""
+proc a(x = {}) = discard