Add sort.Interface implementation for Feed (mmcdole#141)

Order Feed.Items by oldest to newest publish time.
mackenzie-remote · Mar 31, 2020 · 4298e43 · 4298e43
1 parent 2251b44
commit 4298e43
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diff --git a/feed.go b/feed.go
@@ -10,6  10,8 @@ import (
 // Feed is the universal Feed type that atom.Feed
 // and rss.Feed gets translated to. It represents
 // a web feed.
 // Sorting with sort.Sort will order the Items by
 // oldest to newest publish time.
 type Feed struct {
 	Title           string                   `json:"title,omitempty"`
 	Description     string                   `json:"description,omitempty"`
@@ -82,3  84,21 @@ type Enclosure struct {
 	Length string `json:"length,omitempty"`
 	Type   string `json:"type,omitempty"`
 }
 
 // Len returns the length of Items.
 func (f Feed) Len() int {
 	return len(f.Items)
 }
 
 // Less compares PublishedParsed of Items[i], Items[k]
 // and returns true if Items[i] is less than Items[k].
 func (f Feed) Less(i, k int) bool {
 	return f.Items[i].PublishedParsed.Before(
 		*f.Items[k].PublishedParsed,
 	)
 }
 
 // Swap swaps Items[i] and Items[k].
 func (f Feed) Swap(i, k int) {
 	f.Items[i], f.Items[k] = f.Items[k], f.Items[i]
 }
diff --git a/feed_test.go b/feed_test.go
@@ -0,0  1,50 @@
 package gofeed_test
 
 import (
 	"sort"
 	"testing"
 	"time"
 
 	"github.com/mmcdole/gofeed"
 )
 
 func TestFeedSort(t *testing.T) {
 	oldestItem := &gofeed.Item{
 		PublishedParsed: &[]time.Time{time.Unix(0, 0)}[0],
 	}
 	inbetweenItem := &gofeed.Item{
 		PublishedParsed: &[]time.Time{time.Unix(1, 0)}[0],
 	}
 	newestItem := &gofeed.Item{
 		PublishedParsed: &[]time.Time{time.Unix(2, 0)}[0],
 	}
 
 	feed := gofeed.Feed{
 		Items: []*gofeed.Item{
 			newestItem,
 			oldestItem,
 			inbetweenItem,
 		},
 	}
 	expected := gofeed.Feed{
 		Items: []*gofeed.Item{
 			oldestItem,
 			inbetweenItem,
 			newestItem,
 		},
 	}
 
 	sort.Sort(feed)
 
 	for i, item := range feed.Items {
 		if !item.PublishedParsed.Equal(
 			*expected.Items[i].PublishedParsed,
 		) {
 			t.Errorf(
 				"Item PublishedParsed = %s; want %s",
 				item.PublishedParsed,
 				expected.Items[i].PublishedParsed,
 			)
 		}
 	}
 }