Ignore <link> tags with rel=preconnect

wjdp · wjdp · commit c9077f50021e · 2023-01-28T19:58:44.000Z
Refactor ignoring logic to take a list. Closes #202
diff --git a/htmltest/check-link.go b/htmltest/check-link.go
@@ -16,6 +16,11 @@ import (
 	"golang.org/x/net/html"
 )
 
+// ignoredRels: List of rel values to ignore, dns-prefetch and preconnect are ignored as they are not links to be
+//              followed rather telling browser we want something on that host, if the root of that host is not valid,
+//              it's likely not a problem.
+var ignoredRels = [...]string{"dns-prefetch", "preconnect"}
+
 func (hT *HTMLTest) checkLink(document *htmldoc.Document, node *html.Node) {
 	attrs := htmldoc.ExtractAttrs(node.Attr,
 		[]string{"href", "rel"})
@@ -27,10 +32,11 @@ func (hT *HTMLTest) checkLink(document *htmldoc.Document, node *html.Node) {
 		document.State.FaviconPresent = true
 	}
 
-	// Ignore if rel=dns-prefetch, see #40. If we have more cases like this a hashable type should be created and
-	// checked against.
-	if attrs["rel"] == "dns-prefetch" {
-		return
+	// If rel in IgnoredRels, ignore this link
+	for _, rel := range ignoredRels {
+		if attrs["rel"] == rel {
+			return
+		}
 	}
 
 	// Create reference
diff --git a/htmltest/check-link_test.go b/htmltest/check-link_test.go
@@ -690,6 +690,12 @@ func TestLinkRelDnsPrefetch(t *testing.T) {
 	tExpectIssueCount(t, hT, 0)
 }
 
+func TestLinkRelPreconnect(t *testing.T) {
+	// ignores links with rel="preconnect"
+	hT := tTestFile("fixtures/links/link_rel_preconnect.html")
+	tExpectIssueCount(t, hT, 0)
+}
+
 func TestAnchorPre(t *testing.T) {
 	// catches broken links when inside pre or code tags
 	hT := tTestFileOpts("fixtures/links/anchors_in_pre.html",
diff --git a/htmltest/fixtures/links/link_rel_preconnect.html b/htmltest/fixtures/links/link_rel_preconnect.html
@@ -0,0 +1,3 @@
+<head>
+    <link rel="preconnect" href="https://www.googletagmanager.com" />
+</head>

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,3 @@`
	`1`	`+<head>`
	`2`	`+ <link rel="preconnect" href="https://www.googletagmanager.com" />`
	`3`	`+</head>`