Add support for 0-padding in format and replace uses of sprintf

1 files changed, 8 insertions, 1 deletions

diff --git a/src/json.cc b/src/json.cc
index 3661ac80..82fc0f28 100644
--- a/src/json.cc
+++ b/src/json.cc
@@ -29,7 +29,7 @@ String to_json(StringView str)
 
         char buf[7] = {'\\', *next, 0};
         if (*next >= 0 and *next <= 0x1F)
-            sprintf(buf, "\\u%04x", *next);
+            format_to(buf, "\\u{:04}", hex(*next));
 
         res += buf;
         it = next+1;
@@ -188,4 +188,11 @@ UnitTest test_json_parser{[]()
     }
 }};
 
+UnitTest test_to_json{[]()
+{
+    kak_assert(to_json(true) == "true");
+    kak_assert(to_json(false) == "false");
+    kak_assert(to_json(HashMap<String, Vector<int>>{{"foo", {1,2,3}}, {"\033", {3, 4, 5}}}) == R"({"foo": [1, 2, 3],"\u001b": [3, 4, 5]})");
+}};
+
 }