1 files changed, 161 insertions, 0 deletions
diff --git a/vendor/go.opentelemetry.io/otel/attribute/iterator.go b/vendor/go.opentelemetry.io/otel/attribute/iterator.go
new file mode 100644
index 000000000..841b271fb
--- /dev/null
+++ b/vendor/go.opentelemetry.io/otel/attribute/iterator.go
@@ -0,0 +1,161 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package attribute // import "go.opentelemetry.io/otel/attribute"
+
+// Iterator allows iterating over the set of attributes in order, sorted by
+// key.
+type Iterator struct {
+	storage *Set
+	idx     int
+}
+
+// MergeIterator supports iterating over two sets of attributes while
+// eliminating duplicate values from the combined set. The first iterator
+// value takes precedence.
+type MergeIterator struct {
+	one     oneIterator
+	two     oneIterator
+	current KeyValue
+}
+
+type oneIterator struct {
+	iter Iterator
+	done bool
+	attr KeyValue
+}
+
+// Next moves the iterator to the next position. Returns false if there are no
+// more attributes.
+func (i *Iterator) Next() bool {
+	i.idx++
+	return i.idx < i.Len()
+}
+
+// Label returns current KeyValue. Must be called only after Next returns
+// true.
+//
+// Deprecated: Use Attribute instead.
+func (i *Iterator) Label() KeyValue {
+	return i.Attribute()
+}
+
+// Attribute returns the current KeyValue of the Iterator. It must be called
+// only after Next returns true.
+func (i *Iterator) Attribute() KeyValue {
+	kv, _ := i.storage.Get(i.idx)
+	return kv
+}
+
+// IndexedLabel returns current index and attribute. Must be called only
+// after Next returns true.
+//
+// Deprecated: Use IndexedAttribute instead.
+func (i *Iterator) IndexedLabel() (int, KeyValue) {
+	return i.idx, i.Attribute()
+}
+
+// IndexedAttribute returns current index and attribute. Must be called only
+// after Next returns true.
+func (i *Iterator) IndexedAttribute() (int, KeyValue) {
+	return i.idx, i.Attribute()
+}
+
+// Len returns a number of attributes in the iterated set.
+func (i *Iterator) Len() int {
+	return i.storage.Len()
+}
+
+// ToSlice is a convenience function that creates a slice of attributes from
+// the passed iterator. The iterator is set up to start from the beginning
+// before creating the slice.
+func (i *Iterator) ToSlice() []KeyValue {
+	l := i.Len()
+	if l == 0 {
+		return nil
+	}
+	i.idx = -1
+	slice := make([]KeyValue, 0, l)
+	for i.Next() {
+		slice = append(slice, i.Attribute())
+	}
+	return slice
+}
+
+// NewMergeIterator returns a MergeIterator for merging two attribute sets.
+// Duplicates are resolved by taking the value from the first set.
+func NewMergeIterator(s1, s2 *Set) MergeIterator {
+	mi := MergeIterator{
+		one: makeOne(s1.Iter()),
+		two: makeOne(s2.Iter()),
+	}
+	return mi
+}
+
+func makeOne(iter Iterator) oneIterator {
+	oi := oneIterator{
+		iter: iter,
+	}
+	oi.advance()
+	return oi
+}
+
+func (oi *oneIterator) advance() {
+	if oi.done = !oi.iter.Next(); !oi.done {
+		oi.attr = oi.iter.Attribute()
+	}
+}
+
+// Next returns true if there is another attribute available.
+func (m *MergeIterator) Next() bool {
+	if m.one.done && m.two.done {
+		return false
+	}
+	if m.one.done {
+		m.current = m.two.attr
+		m.two.advance()
+		return true
+	}
+	if m.two.done {
+		m.current = m.one.attr
+		m.one.advance()
+		return true
+	}
+	if m.one.attr.Key == m.two.attr.Key {
+		m.current = m.one.attr // first iterator attribute value wins
+		m.one.advance()
+		m.two.advance()
+		return true
+	}
+	if m.one.attr.Key < m.two.attr.Key {
+		m.current = m.one.attr
+		m.one.advance()
+		return true
+	}
+	m.current = m.two.attr
+	m.two.advance()
+	return true
+}
+
+// Label returns the current value after Next() returns true.
+//
+// Deprecated: Use Attribute instead.
+func (m *MergeIterator) Label() KeyValue {
+	return m.current
+}
+
+// Attribute returns the current value after Next() returns true.
+func (m *MergeIterator) Attribute() KeyValue {
+	return m.current
+}