Fix Diff slice bounds out of range (#170)

Fixes #169

functions/diff.go

@@ -23,6 +23,7 @@ func (ss SliceType) Diff(against SliceType) (added, removed SliceType) {
 				if s.Equals(element) {
 					ss2 = append(ss2[:i], ss2[i+1:]...)
 					found = true
+					break
 				}
 			}
 

pie/carpointers_pie.go

@@ -103,6 +103,7 @@ func (ss carPointers) Diff(against carPointers) (added, removed carPointers) {
 				if s.Equals(element) {
 					ss2 = append(ss2[:i], ss2[i+1:]...)
 					found = true
+					break
 				}
 			}
 

pie/cars_pie.go

@@ -103,6 +103,7 @@ func (ss cars) Diff(against cars) (added, removed cars) {
 				if s == element {
 					ss2 = append(ss2[:i], ss2[i+1:]...)
 					found = true
+					break
 				}
 			}
 

pie/float64s_pie.go

@@ -142,6 +142,7 @@ func (ss Float64s) Diff(against Float64s) (added, removed Float64s) {
 				if s == element {
 					ss2 = append(ss2[:i], ss2[i+1:]...)
 					found = true
+					break
 				}
 			}
 

pie/ints_pie.go

@@ -142,6 +142,7 @@ func (ss Ints) Diff(against Ints) (added, removed Ints) {
 				if s == element {
 					ss2 = append(ss2[:i], ss2[i+1:]...)
 					found = true
+					break
 				}
 			}
 

pie/strings_pie.go

@@ -117,6 +117,7 @@ func (ss Strings) Diff(against Strings) (added, removed Strings) {
 				if s == element {
 					ss2 = append(ss2[:i], ss2[i+1:]...)
 					found = true
+					break
 				}
 			}