Fix weird addition bug in iterator

The problem was the matching: We matched, in the addition branches, for
a pair which we then reversed. This caused a strange bug when adding a
moment and a minute.

The subtraction matching was wrong as well, as it also reversed the
order of the arguments.

1 files changed, 7 insertions, 43 deletions

diff --git a/src/timetype.rs b/src/timetype.rs
index db0c05e..cfabe1e 100644
--- a/src/timetype.rs
+++ b/src/timetype.rs
@@ -598,22 +598,11 @@ fn add(a: Box<TimeType>, b: Box<TimeType>) -> Result<TimeType> {
         (thing, TT::Moment(mom)) => Err(KE::from_kind(KEK::CannotAdd(thing, TT::Moment(mom)))),
 
         (TT::Seconds(a), other) => add_to_seconds(a, other),
-        (other, TT::Seconds(a)) => add_to_seconds(a, other),
-
         (TT::Minutes(a), other) => add_to_minutes(a, other),
-        (other, TT::Minutes(a)) => add_to_minutes(a, other),
-
         (TT::Hours(a), other)   => add_to_hours(a, other),
-        (other, TT::Hours(a))   => add_to_hours(a, other),
-
         (TT::Days(a), other)    => add_to_days(a, other),
-        (other, TT::Days(a))    => add_to_days(a, other),
-
         (TT::Months(a), other)  => add_to_months(a, other),
-        (other, TT::Months(a))  => add_to_months(a, other),
-
         (TT::Years(a), other)   => add_to_years(a, other),
-        (other, TT::Years(a))   => add_to_years(a, other),
 
         (TT::Addition(a, b), other)      => add(a, b)
             .map(Box::new)
@@ -683,7 +672,7 @@ fn add_to_minutes(amount: i64, tt: TimeType) -> Result<TimeType> {
         TT::EndOfHour(e)      => Err(KE::from_kind(KEK::CannotAdd(TT::Minutes(amount), TT::EndOfHour(e)))),
         TT::EndOfMinute(e)    => Err(KE::from_kind(KEK::CannotAdd(TT::Minutes(amount), TT::EndOfMinute(e)))),
         TT::Addition(b, c)    => add_to_minutes(amount, try!(add(b, c))),
-        TT::Subtraction(b, c) => add_to_minutes(amount, try!(sub(b, c))),
+        TT::Subtraction(b, c) => sub_from_minutes(amount, try!(sub(b, c))),
     }
 }
 
@@ -875,37 +864,12 @@ fn sub(a: Box<TimeType>, b: Box<TimeType>) -> Result<TimeType> {
 
     match (*a, *b) {
         (TT::Moment(mom), thing) => sub_from_moment(mom, thing),
-        (thing, TT::Moment(mom)) => Err(KE::from_kind(KEK::CannotSub(thing, TT::Moment(mom)))),
-
-        (TT::Seconds(a), other) => sub_from_seconds(a, other),
-        (other, TT::Seconds(a)) => do_calculate(other)
-            .map(Box::new)
-            .and_then(|br| sub(br, Box::new(TT::Seconds(a)))), // recurses into match branch above
-
-        (TT::Minutes(a), other) => sub_from_minutes(a, other),
-        (other, TT::Minutes(a)) => do_calculate(other)
-            .map(Box::new)
-            .and_then(|br| sub(br, Box::new(TT::Minutes(a)))), // recurses into match branch above
-
-        (TT::Hours(a), other)   => sub_from_hours(a, other),
-        (other, TT::Hours(a))   => do_calculate(other)
-            .map(Box::new)
-            .and_then(|br| sub(br, Box::new(TT::Hours(a)))), // recurses into match branch above
-
-        (TT::Days(a), other)    => sub_from_days(a, other),
-        (other, TT::Days(a))    => do_calculate(other)
-            .map(Box::new)
-            .and_then(|br| sub(br, Box::new(TT::Days(a)))), // recurses into match branch above
-
-        (TT::Months(a), other)  => sub_from_months(a, other),
-        (other, TT::Months(a))  => do_calculate(other)
-            .map(Box::new)
-            .and_then(|br| sub(br, Box::new(TT::Months(a)))), // recurses into match branch above
-
-        (TT::Years(a), other)   => sub_from_years(a, other),
-        (other, TT::Years(a))   => do_calculate(other)
-            .map(Box::new)
-            .and_then(|br| sub(br, Box::new(TT::Years(a)))), // recurses into match branch above
+        (TT::Seconds(a), other)  => sub_from_seconds(a, other),
+        (TT::Minutes(a), other)  => sub_from_minutes(a, other),
+        (TT::Hours(a), other)    => sub_from_hours(a, other),
+        (TT::Days(a), other)     => sub_from_days(a, other),
+        (TT::Months(a), other)   => sub_from_months(a, other),
+        (TT::Years(a), other)    => sub_from_years(a, other),
 
         (TT::Subtraction(a, b), other)   => sub(a, b)
             .map(Box::new)