Render links for commit hashes followed by comma (#14224)

Regex test cases: https://regex101.com/r/mVbPxM/2/

fixes #14223

modules/markup/html.go

@@ -43,7 +43,7 @@ var (
 	// sha1CurrentPattern matches string that represents a commit SHA, e.g. d8a994ef243349f321568f9e36d5c3f444b99cae
 	// Although SHA1 hashes are 40 chars long, the regex matches the hash from 7 to 40 chars in length
 	// so that abbreviated hash links can be used as well. This matches git and github useability.
-	sha1CurrentPattern = regexp.MustCompile(`(?:\s|^|\(|\[)([0-9a-f]{7,40})(?:\s|$|\)|\]|\.(\s|$))`)
+	sha1CurrentPattern = regexp.MustCompile(`(?:\s|^|\(|\[)([0-9a-f]{7,40})(?:\s|$|\)|\]|[.,](\s|$))`)
 
 	// shortLinkPattern matches short but difficult to parse [[name|link|arg=test]] syntax
 	shortLinkPattern = regexp.MustCompile(`\[\[(.*?)\]\](\w*)`)

modules/markup/html_test.go

@@ -46,6 +46,12 @@ func TestRender_Commits(t *testing.T) {
 	test("/home/gitea/"+sha, "<p>/home/gitea/"+sha+"</p>")
 	test("deadbeef", `<p>deadbeef</p>`)
 	test("d27ace93", `<p>d27ace93</p>`)
+	test(sha[:14]+".x", `<p>`+sha[:14]+`.x</p>`)
+
+	expected14 := `<a href="` + commit[:len(commit)-(40-14)] + `" rel="nofollow"><code>` + sha[:10] + `</code></a>`
+	test(sha[:14]+".", `<p>`+expected14+`.</p>`)
+	test(sha[:14]+",", `<p>`+expected14+`,</p>`)
+	test("["+sha[:14]+"]", `<p>[`+expected14+`]</p>`)
 }
 
 func TestRender_CrossReferences(t *testing.T) {