[njs] Added support for accessor properties in JSON.stringify().

[Dmitry Volyntsev]

details:   https://hg.nginx.org/njs/rev/239f3511397b
branches:  
changeset: 1118:239f3511397b
user:      Dmitry Volyntsev <xeioex at nginx.com>
date:      Thu Aug 08 14:19:56 2019 +0300
description:
Added support for accessor properties in JSON.stringify().

This closes #203 issue on Github.

diffstat:

 src/njs_json.c           |  27 ++++++++++++++++++++++-----
 src/test/njs_unit_test.c |   8 ++++++++
 2 files changed, 30 insertions(+), 5 deletions(-)

diffs (62 lines):

diff -r fd09c657f97d -r 239f3511397b src/njs_json.c
--- a/src/njs_json.c	Thu Aug 08 14:19:55 2019 +0300
+++ b/src/njs_json.c	Thu Aug 08 14:19:56 2019 +0300
@@ -1214,7 +1214,7 @@ njs_json_stringify_iterator(njs_vm_t *vm
     njs_value_t         *key, *value;
     njs_function_t      *to_json;
     njs_json_state_t    *state;
-    njs_object_prop_t   *prop;
+    njs_object_prop_t   *prop, scratch;
     njs_lvlhsh_query_t  lhq;
 
 start:
@@ -1255,10 +1255,27 @@ start:
 
             prop = lhq.value;
 
-            if (!prop->enumerable
-                || njs_is_undefined(&prop->value)
-                || !njs_is_valid(&prop->value)
-                || njs_is_function(&prop->value))
+            if (!prop->enumerable) {
+                break;
+            }
+
+            if (njs_is_accessor_descriptor(prop)
+                && njs_is_function(&prop->getter))
+            {
+                scratch = *prop;
+                prop = &scratch;
+
+                ret = njs_function_apply(vm, njs_function(&prop->getter),
+                                         &state->value, 1, &prop->value);
+
+                if (njs_slow_path(ret != NJS_OK)) {
+                    return ret;
+                }
+            }
+
+            if (njs_is_undefined(&prop->value)
+                || njs_is_function(&prop->value)
+                || !njs_is_valid(&prop->value))
             {
                 break;
             }
diff -r fd09c657f97d -r 239f3511397b src/test/njs_unit_test.c
--- a/src/test/njs_unit_test.c	Thu Aug 08 14:19:55 2019 +0300
+++ b/src/test/njs_unit_test.c	Thu Aug 08 14:19:56 2019 +0300
@@ -12766,6 +12766,14 @@ static njs_unit_test_t  njs_test[] =
     { njs_str("JSON.stringify([{a:1,b:{c:2}},1], undefined, new Date())"),
       njs_str("[{\"a\":1,\"b\":{\"c\":2}},1]") },
 
+    { njs_str("var o = Object.defineProperty({}, 'a', { get() { return ()=> 1}, enumerable: true });"
+              "JSON.stringify(o)"),
+      njs_str("{}") },
+
+    { njs_str("var o = Object.defineProperty({}, 'a', { get: () => ({b:1, c:2}), enumerable: true });"
+              "JSON.stringify(o)"),
+      njs_str("{\"a\":{\"b\":1,\"c\":2}}") },
+
     { njs_str("JSON.stringify({toJSON:function(k){}})"),
       njs_str("undefined") },