detector_test.go

package gofeed_test

import (
	"bytes"
	"errors"
	"fmt"
	"io"
	"strings"
	"testing"
	"testing/iotest"

	"github.com/mmcdole/gofeed"
	"github.com/mmcdole/gofeed/internal/testutil"
	"github.com/stretchr/testify/assert"
)

func TestDetectFeedType(t *testing.T) {
	var feedTypeTests = []struct {
		file     string
		expected gofeed.FeedType
	}{
		{"atom03_feed.xml", gofeed.FeedTypeAtom},
		{"atom10_feed.xml", gofeed.FeedTypeAtom},
		{"rss_feed.xml", gofeed.FeedTypeRSS},
		{"rss_feed_bom.xml", gofeed.FeedTypeRSS},
		{"rss_feed_leading_spaces.xml", gofeed.FeedTypeRSS},
		{"rdf_feed.xml", gofeed.FeedTypeRSS},
		{"unknown_feed.xml", gofeed.FeedTypeUnknown},
		{"empty_feed.xml", gofeed.FeedTypeUnknown},
		{"json10_feed.json", gofeed.FeedTypeJSON},
	}

	for _, test := range feedTypeTests {
		t.Run(test.file, func(t *testing.T) {
			data := testutil.ReadFile(t, "testdata/parser/universal/"+test.file)
			actual := gofeed.DetectFeedType(bytes.NewReader(data))
			assert.Equal(t, test.expected, actual)
		})
	}
}

// Examples

func ExampleDetectFeedType() {
	feedData := `<rss version="2.0">
<channel>
<title>Sample Feed</title>
</channel>
</rss>`
	feedType := gofeed.DetectFeedType(strings.NewReader(feedData))
	if feedType == gofeed.FeedTypeRSS {
		fmt.Println("Wow! This is an RSS feed!")
	}
}

// A reader that fails mid-stream must yield FeedTypeUnknown, not a type
// guessed from the partial prefix (issue #311).
func TestDetectFeedType_ReaderError(t *testing.T) {
	r := io.MultiReader(strings.NewReader(`<rss version="2.0"></rss>`), iotest.ErrReader(errors.New("boom")))
	assert.Equal(t, gofeed.FeedTypeUnknown, gofeed.DetectFeedType(r))
}

// JSON detection must work from a bounded prefix; the JSON parser validates
// the complete document after detection (issue #344).
func TestDetectFeedType_JSONPrefix(t *testing.T) {
	prefix := `{"version":"https://jsonfeed.org/version/1.1","items":[{`
	assert.Equal(t, gofeed.FeedTypeJSON, gofeed.DetectFeedType(strings.NewReader(prefix)))
}