Add function to subtract an entry from an IDList

report/id_list.go

@@ -36,3 +36,8 @@ func (a IDList) Contains(id string) bool {
 func (a IDList) Intersection(b IDList) IDList {
 	return IDList(StringSet(a).Intersection(StringSet(b)))
 }
+
+// Minus returns the set with id removed
+func (a IDList) Minus(id string) IDList {
+	return IDList(StringSet(a).Minus(id))
+}

report/string_set.go

@@ -50,6 +50,15 @@ func (s StringSet) Intersection(b StringSet) StringSet {
 	return result
 }
 
+// Minus returns the set with str removed
+func (s StringSet) Minus(str string) StringSet {
+	i := sort.Search(len(s), func(i int) bool { return s[i] >= str })
+	if i < len(s) && s[i] == str {
+		return append(s[:i], s[i+1:]...)
+	}
+	return s
+}
+
 // Equal returns true if a and b have the same contents
 func (s StringSet) Equal(b StringSet) bool {
 	if len(s) != len(b) {