src/timetable: Normalise out of range months

diff --git a/spec/timetable_spec.lua b/spec/timetable_spec.lua
index 38ded15864b109e416d0cfd6a704c8f957ae3350..9a16af50da38b304f122107c828026a324bb54c1 100644 (file)
--- a/spec/timetable_spec.lua
+++ b/spec/timetable_spec.lua
@@ -49,5 +49,9 @@ describe ( "Time table library" , function ( )
                                assert.same ( native_timestamp ( y,m,1 ) , timetable.timestamp(y,m,1,0,0,0) )
                        end
                end
-       end)
+       end )
+
+       it ( "Out of range month is normalised" , function ( )
+               assert.same ( { timetable.normalise(2013,0,1,0,0,0) } , { 2012,12,1,0,0,0 } )
+       end )
 end )

diff --git a/src/timetable.lua b/src/timetable.lua
index bacc58cbfe136d46cb8448915987d94d69d5ca6e..aef8ca42e1ed89681e49d8c97ee90d4c3acfd613 100644 (file)
--- a/src/timetable.lua
+++ b/src/timetable.lua
@@ -21,6 +21,7 @@ local function year_length ( y )
 end
 
 local function month_length ( m , y )
+       m = ( m - 1 ) % 12 + 1
        if m == 2 then
                return is_leap ( y ) and 29 or 28
        else