2 files changed, 31 insertions, 14 deletions
diff --git a/test/functional/eval/json_functions_spec.lua b/test/functional/eval/json_functions_spec.lua
index 4d34cde849..8dcaea806e 100644
--- a/test/functional/eval/json_functions_spec.lua
+++ b/test/functional/eval/json_functions_spec.lua
@@ -776,4 +776,11 @@ describe('json_encode() function', function()
   it('can dump NULL dictionary', function()
     eq('{}', eval('json_encode(v:_null_dict)'))
   end)
+
+  it('fails to parse NULL strings and lists', function()
+    eq('Vim(call):E474: Attempt to decode a blank string',
+       exc_exec('call json_decode($XXX_UNEXISTENT_VAR_XXX)'))
+    eq('Vim(call):E474: Attempt to decode a blank string',
+       exc_exec('call json_decode(v:_null_list)'))
+  end)
 end)
diff --git a/test/functional/eval/server_spec.lua b/test/functional/eval/server_spec.lua
index 115114c3c3..393616838e 100644
--- a/test/functional/eval/server_spec.lua
+++ b/test/functional/eval/server_spec.lua
@@ -63,23 +63,33 @@ describe('serverstart(), serverstop()', function()
     eq({}, funcs.serverlist())
 
     local s = funcs.serverstart('127.0.0.1:0')  -- assign random port
-    assert(string.match(s, '127.0.0.1:%d+'))
-    eq(s, funcs.serverlist()[1])
-    clear_serverlist()
+    if #s > 0 then
+      assert(string.match(s, '127.0.0.1:%d+'))
+      eq(s, funcs.serverlist()[1])
+      clear_serverlist()
+    end
 
     s = funcs.serverstart('127.0.0.1:')  -- assign random port
-    assert(string.match(s, '127.0.0.1:%d+'))
-    eq(s, funcs.serverlist()[1])
-    clear_serverlist()
+    if #s > 0 then
+      assert(string.match(s, '127.0.0.1:%d+'))
+      eq(s, funcs.serverlist()[1])
+      clear_serverlist()
+    end
 
-    funcs.serverstart('127.0.0.1:12345')
-    funcs.serverstart('127.0.0.1:12345')  -- exists already; ignore
-    funcs.serverstart('::1:12345')
-    funcs.serverstart('::1:12345')        -- exists already; ignore
-    local expected = {
-      '127.0.0.1:12345',
-      '::1:12345',
-    }
+    local expected = {}
+    local v4 = '127.0.0.1:12345'
+    s = funcs.serverstart(v4)
+    if #s > 0 then
+      table.insert(expected, v4)
+      funcs.serverstart(v4)  -- exists already; ignore
+    end
+
+    local v6 = '::1:12345'
+    s = funcs.serverstart(v6)
+    if #s > 0 then
+      table.insert(expected, v6)
+      funcs.serverstart(v6)  -- exists already; ignore
+    end
     eq(expected, funcs.serverlist())
     clear_serverlist()