diff --git a/src/testdir/test_json.vim b/src/testdir/test_json.vim
index 52cffc8..2534de1 100644
--- a/src/testdir/test_json.vim
+++ b/src/testdir/test_json.vim
@@ -32,9 +32,12 @@
 let s:varl3 = [l3, l3]
 
 let s:jsond1 = '{"a":1,"b":"bee","c":[1,2]}'
+let s:jsd1 = '{a:1,b:"bee",c:[1,2]}'
 let s:vard1 = {"a": 1, "b": "bee","c": [1,2]}
 let s:jsond2 = '{"1":1,"2":{"a":"aa","b":{},"c":"cc"},"3":3}'
+let s:jsd2 = '{"1":1,"2":{a:"aa",b:{},c:"cc"},"3":3}'
 let s:jsond2s = "  { \"1\" : 1 , \"2\" :\n{ \"a\"\r: \"aa\" , \"b\" : {\<Tab>} , \"c\" : \"cc\" } , \"3\" : 3 }\r\n"
+let s:jsd2s = "  { \"1\" : 1 , \"2\" :\n{ a\r: \"aa\" , b : {\<Tab>} , c : \"cc\" } , \"3\" : 3 }\r\n"
 let s:vard2 = {"1": 1, "2": 2, "3": 3}
 let d2 = {"a": "aa", "b": s:vard2, "c": "cc"}
 let s:vard2["2"] = d2
@@ -42,11 +45,16 @@
 let d3 = {"a": 1, "b": 2}
 let s:vard3 = {"x": d3, "y": d3}
 let s:jsond3 = '{"x":{"a":1,"b":2},"y":{"a":1,"b":2}}'
+let s:jsd3 = '{x:{a:1,b:2},y:{a:1,b:2}}'
+let s:vard4 = {"key": v:none}
+let s:vard4x = {"key": v:null}
+let s:jsond4 = '{"key":null}'
+let s:jsd4 = '{key:null}'
 
-let s:jsonvals = '[true,false,,null]'
-let s:varvals = [v:true, v:false, v:none, v:null]
+let s:jsonvals = '[true,false,null,null]'
+let s:varvals = [v:true, v:false, v:null, v:null]
 
-func Test_encode()
+func Test_json_encode()
   call assert_equal(s:json1, jsonencode(s:var1))
   call assert_equal(s:json2, jsonencode(s:var2))
   call assert_equal(s:json3, jsonencode(s:var3))
@@ -69,18 +77,18 @@
   call assert_equal(s:jsond1, jsonencode(s:vard1))
   call assert_equal(s:jsond2, jsonencode(s:vard2))
   call assert_equal(s:jsond3, jsonencode(s:vard3))
+  call assert_equal(s:jsond4, jsonencode(s:vard4))
 
   call assert_equal(s:jsonvals, jsonencode(s:varvals))
 
   call assert_fails('echo jsonencode(function("tr"))', 'E474:')
   call assert_fails('echo jsonencode([function("tr")])', 'E474:')
-  call assert_fails('echo jsonencode({"key":v:none})', 'E474:')
 
   silent! let res = jsonencode(function("tr"))
   call assert_equal("", res)
 endfunc
 
-func Test_decode()
+func Test_json_decode()
   call assert_equal(s:var1, jsondecode(s:json1))
   call assert_equal(s:var2, jsondecode(s:json2))
   call assert_equal(s:var3, jsondecode(s:json3))
@@ -103,7 +111,9 @@
 
   call assert_equal(s:vard1, jsondecode(s:jsond1))
   call assert_equal(s:vard2x, jsondecode(s:jsond2))
+  call assert_equal(s:vard2x, jsondecode(s:jsond2s))
   call assert_equal(s:vard3, jsondecode(s:jsond3))
+  call assert_equal(s:vard4x, jsondecode(s:jsond4))
 
   call assert_equal(s:varvals, jsondecode(s:jsonvals))
 
@@ -134,4 +144,110 @@
   call assert_fails('call jsondecode("[1")', "E474:")
   call assert_fails('call jsondecode("[1,")', "E474:")
   call assert_fails('call jsondecode("[1 2]")', "E474:")
+
+  call assert_fails('call jsondecode("[1,,2]")', "E474:")
+endfunc
+
+let s:jsl5 = '[7,,,]'
+let s:varl5 = [7, v:none, v:none]
+
+func Test_js_encode()
+  call assert_equal(s:json1, jsencode(s:var1))
+  call assert_equal(s:json2, jsencode(s:var2))
+  call assert_equal(s:json3, jsencode(s:var3))
+  call assert_equal(s:json4, jsencode(s:var4))
+  call assert_equal(s:json5, jsencode(s:var5))
+
+  if has('multi_byte')
+    call assert_equal(s:jsonmb, jsencode(s:varmb))
+  endif
+
+  call assert_equal(s:jsonnr, jsencode(s:varnr))
+  if has('float')
+    call assert_equal(s:jsonfl, jsencode(s:varfl))
+  endif
+
+  call assert_equal(s:jsonl1, jsencode(s:varl1))
+  call assert_equal(s:jsonl2, jsencode(s:varl2))
+  call assert_equal(s:jsonl3, jsencode(s:varl3))
+
+  call assert_equal(s:jsd1, jsencode(s:vard1))
+  call assert_equal(s:jsd2, jsencode(s:vard2))
+  call assert_equal(s:jsd3, jsencode(s:vard3))
+  call assert_equal(s:jsd4, jsencode(s:vard4))
+
+  call assert_equal(s:jsonvals, jsencode(s:varvals))
+
+  call assert_fails('echo jsencode(function("tr"))', 'E474:')
+  call assert_fails('echo jsencode([function("tr")])', 'E474:')
+
+  silent! let res = jsencode(function("tr"))
+  call assert_equal("", res)
+
+  call assert_equal(s:jsl5, jsencode(s:varl5))
+endfunc
+
+func Test_js_decode()
+  call assert_equal(s:var1, jsdecode(s:json1))
+  call assert_equal(s:var2, jsdecode(s:json2))
+  call assert_equal(s:var3, jsdecode(s:json3))
+  call assert_equal(s:var4, jsdecode(s:json4))
+  call assert_equal(s:var5, jsdecode(s:json5))
+
+  if has('multi_byte')
+    call assert_equal(s:varmb, jsdecode(s:jsonmb))
+  endif
+
+  call assert_equal(s:varnr, jsdecode(s:jsonnr))
+  if has('float')
+    call assert_equal(s:varfl, jsdecode(s:jsonfl))
+  endif
+
+  call assert_equal(s:varl1, jsdecode(s:jsonl1))
+  call assert_equal(s:varl2x, jsdecode(s:jsonl2))
+  call assert_equal(s:varl2x, jsdecode(s:jsonl2s))
+  call assert_equal(s:varl3, jsdecode(s:jsonl3))
+
+  call assert_equal(s:vard1, jsdecode(s:jsond1))
+  call assert_equal(s:vard1, jsdecode(s:jsd1))
+  call assert_equal(s:vard2x, jsdecode(s:jsond2))
+  call assert_equal(s:vard2x, jsdecode(s:jsd2))
+  call assert_equal(s:vard2x, jsdecode(s:jsond2s))
+  call assert_equal(s:vard2x, jsdecode(s:jsd2s))
+  call assert_equal(s:vard3, jsdecode(s:jsond3))
+  call assert_equal(s:vard3, jsdecode(s:jsd3))
+  call assert_equal(s:vard4x, jsdecode(s:jsond4))
+  call assert_equal(s:vard4x, jsdecode(s:jsd4))
+
+  call assert_equal(s:varvals, jsdecode(s:jsonvals))
+
+  call assert_equal(v:true, jsdecode('true'))
+  call assert_equal(type(v:true), type(jsdecode('true')))
+  call assert_equal(v:none, jsdecode(''))
+  call assert_equal(type(v:none), type(jsdecode('')))
+  call assert_equal("", jsdecode('""'))
+
+  call assert_equal({'n': 1}, jsdecode('{"n":1,}'))
+
+  call assert_fails('call jsdecode("\"")', "E474:")
+  call assert_fails('call jsdecode("blah")', "E474:")
+  call assert_fails('call jsdecode("true blah")', "E474:")
+  call assert_fails('call jsdecode("<foobar>")', "E474:")
+
+  call assert_fails('call jsdecode("{")', "E474:")
+  call assert_fails('call jsdecode("{foobar}")', "E474:")
+  call assert_fails('call jsdecode("{\"n\",")', "E474:")
+  call assert_fails('call jsdecode("{\"n\":")', "E474:")
+  call assert_fails('call jsdecode("{\"n\":1")', "E474:")
+  call assert_fails('call jsdecode("{\"n\":1,")', "E474:")
+  call assert_fails('call jsdecode("{\"n\",1}")', "E474:")
+  call assert_fails('call jsdecode("{-}")', "E474:")
+
+  call assert_fails('call jsdecode("[foobar]")', "E474:")
+  call assert_fails('call jsdecode("[")', "E474:")
+  call assert_fails('call jsdecode("[1")', "E474:")
+  call assert_fails('call jsdecode("[1,")', "E474:")
+  call assert_fails('call jsdecode("[1 2]")', "E474:")
+
+  call assert_equal(s:varl5, jsdecode(s:jsl5))
 endfunc