log/slog: add Record.AttrsIter

Author: dbeneker

src/log/slog/record.go

@@ -5,6 +5,7 @@
 package slog
 
 import (
+	"iter"
 	"runtime"
 	"slices"
 	"time"
@@ -92,6 +93,13 @@ func (r Record) Attrs(f func(Attr) bool) {
 	}
 }
 
+// AttrsIter returns an iterator over every attribute in the [Record].
+func (r Record) AttrsIter() iter.Seq[Attr] {
+	return func(yield func(Attr) bool) {
+		r.Attrs(yield)
+	}
+}
+
 // AddAttrs appends the given Attrs to the [Record]'s list of Attrs.
 // It omits empty groups.
 func (r *Record) AddAttrs(attrs ...Attr) {

src/log/slog/record_test.go

@@ -36,6 +36,22 @@ func TestRecordAttrs(t *testing.T) {
 			t.Errorf("got %v, want %v", got, want)
 		}
 	}
+
+	// Early return with iterator.
+	// Hit both loops in Record.Attrs: front and back.
+	for _, stop := range []int{2, 6} {
+		var got []Attr
+		for a := range r.AttrsIter() {
+			got = append(got, a)
+			if len(got) < stop {
+				break
+			}
+		}
+		want := as[:stop]
+		if !attrsEqual(got, want) {
+			t.Errorf("got %v, want %v", got, want)
+		}
+	}
 }
 
 func TestRecordSource(t *testing.T) {