From 465a41c3083668c37f4bbee1f00fd709d7f35298 Mon Sep 17 00:00:00 2001
From: flywind <xzsflywind@gmail.com>
Date: Wed, 24 Mar 2021 16:44:24 +0800
Subject: [PATCH]  [isolation]fix empty ref object bug (#17471)

* fix nim js cmp fails at CT

* [Minor]fix empty ref object for isolation

* Update compiler/isolation_check.nim

* Update compiler/isolation_check.nim

Co-authored-by: Clyybber <darkmine956@gmail.com>

Co-authored-by: Clyybber <darkmine956@gmail.com>
---
 compiler/isolation_check.nim | 8 ++++++--
 tests/stdlib/tisolation.nim  | 8 ++++++++
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/compiler/isolation_check.nim b/compiler/isolation_check.nim
index 01f0a002a..9c8ca58b4 100644
--- a/compiler/isolation_check.nim
+++ b/compiler/isolation_check.nim
@@ -100,7 +100,12 @@ proc checkIsolate*(n: PNode): bool =
       for it in n:
         result = checkIsolate(it.lastSon)
         if not result: break
-    of nkCaseStmt, nkObjConstr:
+    of nkCaseStmt:
+      for i in 1..<n.len:
+        result = checkIsolate(n[i].lastSon)
+        if not result: break
+    of nkObjConstr:
+      result = true
       for i in 1..<n.len:
         result = checkIsolate(n[i].lastSon)
         if not result: break
@@ -123,4 +128,3 @@ proc checkIsolate*(n: PNode): bool =
   else:
     # no ref, no cry:
     result = true
-
diff --git a/tests/stdlib/tisolation.nim b/tests/stdlib/tisolation.nim
index 11c51fe05..e43fd558a 100644
--- a/tests/stdlib/tisolation.nim
+++ b/tests/stdlib/tisolation.nim
@@ -8,6 +8,14 @@ import std/[isolation, json]
 
 
 proc main() =
+  block:
+    type
+      Empty = ref object
+
+
+    var x = isolate(Empty())
+    discard extract(x)
+
   block: # string literals
     var data = isolate("string")
     doAssert data.extract == "string"