X-Git-Url: https://git.madduck.net/etc/awesome.git/blobdiff_plain/6c4658848c01ae0862a2fcad7f6565efd9aa948d..cdaad9ec35371fcfc3b398b7302f1e8fe313b4f6:/luatz/timetable.lua

diff --git a/luatz/timetable.lua b/luatz/timetable.lua
index 3e80242..6bae913 100644
--- a/luatz/timetable.lua
+++ b/luatz/timetable.lua
@@ -1,8 +1,16 @@
 local strftime = require "luatz.strftime".strftime
 local strformat = string.format
 local floor = math.floor
-local function idiv ( n , d )
-	return floor ( n / d )
+local idiv do
+	-- Try and use actual integer division when available (Lua 5.3+)
+	local idiv_loader = (loadstring or load)([[return function(n,d) return n//d end]], "idiv") -- luacheck: ignore 113
+	if idiv_loader then
+		idiv = idiv_loader()
+	else
+		idiv = function(n, d)
+			return floor(n/d)
+		end
+	end
 end
 
 
@@ -68,8 +76,8 @@ local function carry ( tens , units , base )
 		tens  = tens + idiv ( units , base )
 		units = units % base
 	elseif units < 0 then
-		tens  = tens - 1 + idiv ( -units , base )
-		units = base - ( -units % base )
+		tens  = tens + idiv ( units , base )
+		units = ( base + units ) % base
 	end
 	return tens , units
 end
@@ -99,8 +107,12 @@ local function normalise ( year , month , day , hour , min , sec )
 	-- Add a whole year of days at a time, this is later resolved by adding months
 	-- TODO[OPTIMIZE]: This could be slow if `day` is far out of range
 	while day < 0 do
-		year = year - 1
-		day  = day + year_length ( year )
+		month = month - 1
+		if month < 0 then
+			year = year - 1
+			month = 11
+		end
+		day = day + month_length ( month + 1 , year )
 	end
 	year , month = carry ( year , month , 12 )
 
@@ -171,8 +183,10 @@ function timetable_methods:timestamp ( )
 end
 
 function timetable_methods:rfc_3339 ( )
-	-- %06.3f gives 3 (=6-3) digits after decimal
-	return strformat ( "%04u-%02u-%02uT%02u:%02u:%06.3f" , self:unpack ( ) )
+	local year, month, day, hour, min, fsec = self:unpack()
+	local sec, msec = borrow(fsec, 0, 1000)
+	msec = math.floor(msec)
+	return strformat ( "%04u-%02u-%02uT%02u:%02u:%02d.%03d" , year , month , day , hour , min , sec , msec )
 end
 
 function timetable_methods:strftime ( format_string )
@@ -227,7 +241,7 @@ local function new_from_timestamp ( ts )
 	if type ( ts ) ~= "number" then
 		error ( "bad argument #1 to 'new_from_timestamp' (number expected, got " .. type ( ts ) .. ")" , 2 )
 	end
-	return new_timetable ( 1970 , 1 , 1 , 0 , 0 , ts )
+	return new_timetable ( 1970 , 1 , 1 , 0 , 0 , ts ):normalise ( )
 end
 
 return {