extmod/modujson: Add support for dump/dumps separators keyword-argument.

Optionally enabled via MICROPY_PY_UJSON_SEPARATORS.  Enabled by default.

For dump, make sure mp_get_stream_raise is called after
mod_ujson_separators since CPython does it in this order (if both
separators and stream are invalid, separators will raise an exception
first).

Add separators argument in the docs as well.

Signed-off-by: Peter Züger <zueger.peter@icloud.com>
Signed-off-by: Damien George <damien@micropython.org>

1 files changed, 6 insertions, 1 deletions

diff --git a/py/objlist.c b/py/objlist.c
index 8c989facc..f431e273d 100644
--- a/py/objlist.c
+++ b/py/objlist.c
@@ -44,13 +44,18 @@ STATIC mp_obj_t list_pop(size_t n_args, const mp_obj_t *args);
 
 STATIC void list_print(const mp_print_t *print, mp_obj_t o_in, mp_print_kind_t kind) {
     mp_obj_list_t *o = MP_OBJ_TO_PTR(o_in);
+    const char *item_separator = ", ";
     if (!(MICROPY_PY_UJSON && kind == PRINT_JSON)) {
         kind = PRINT_REPR;
+    } else {
+        #if MICROPY_PY_UJSON_SEPARATORS
+        item_separator = MP_PRINT_GET_EXT(print)->item_separator;
+        #endif
     }
     mp_print_str(print, "[");
     for (size_t i = 0; i < o->len; i++) {
         if (i > 0) {
-            mp_print_str(print, ", ");
+            mp_print_str(print, item_separator);
         }
         mp_obj_print_helper(print, o->items[i], kind);
     }