src/loslib.js: Calculate yday of passed in Date, not the current date

2 files changed, 2 insertions, 2 deletions

diff --git a/src/loslib.js b/src/loslib.js
index b58b368..89b5399 100644
--- a/src/loslib.js
+++ b/src/loslib.js
@@ -76,8 +76,7 @@ const setallfields = function(L, time, utc) {
     setfield(L, "month", (utc ? time.getUTCMonth()   : time.getMonth()) + 1);
     setfield(L, "year",  utc ? time.getUTCFullYear() : time.getFullYear());
     setfield(L, "wday",  (utc ? time.getUTCDay()     : time.getDay()) + 1);
-    let now = new Date();
-    setfield(L, "yday", Math.floor((now - (new Date(now.getFullYear(), 0, 0))) / (1000 * 60 * 60 * 24)));
+    setfield(L, "yday", Math.floor((time - (new Date(time.getFullYear(), 0, 0 /* shortcut to correct day by one */))) / 86400000));
     // setboolfield(L, "isdst", time.get);
 };
 
diff --git a/test/loslib.test.js b/test/loslib.test.js
index 02735cb..e2b626e 100644
--- a/test/loslib.test.js
+++ b/test/loslib.test.js
@@ -120,6 +120,7 @@ test('os.time normalisation of table', () => {
         assert(t.month == 2, "unmodified month")
         assert(t.year == 2018, "unmodified year")
         assert(t.wday == 3, "correct wday")
+        assert(t.yday == 51, "correct yday")
     `;
     lualib.luaL_openlibs(L);
     expect(lauxlib.luaL_loadstring(L, to_luastring(luaCode))).toBe(lua.LUA_OK);