Use relative links for commits, mentions, and issues in markdown

modules/markup/html.go

@@ -609,7 +609,7 @@ func mentionProcessor(ctx *RenderContext, node *html.Node) {
 		if ok && strings.Contains(mention, "/") {
 			mentionOrgAndTeam := strings.Split(mention, "/")
 			if mentionOrgAndTeam[0][1:] == ctx.Metas["org"] && strings.Contains(teams, ","+strings.ToLower(mentionOrgAndTeam[1])+",") {
-				replaceContent(node, loc.Start, loc.End, createLink(util.URLJoin(setting.AppURL, "org", ctx.Metas["org"], "teams", mentionOrgAndTeam[1]), mention, "mention"))
+				replaceContent(node, loc.Start, loc.End, createLink(util.URLJoin(ctx.Links.Prefix(), "org", ctx.Metas["org"], "teams", mentionOrgAndTeam[1]), mention, "mention"))
 				node = node.NextSibling.NextSibling
 				start = 0
 				continue
@@ -620,7 +620,7 @@ func mentionProcessor(ctx *RenderContext, node *html.Node) {
 		mentionedUsername := mention[1:]
 
 		if DefaultProcessorHelper.IsUsernameMentionable != nil && DefaultProcessorHelper.IsUsernameMentionable(ctx.Ctx, mentionedUsername) {
-			replaceContent(node, loc.Start, loc.End, createLink(util.URLJoin(setting.AppURL, mentionedUsername), mention, "mention"))
+			replaceContent(node, loc.Start, loc.End, createLink(util.URLJoin(ctx.Links.Prefix(), mentionedUsername), mention, "mention"))
 			node = node.NextSibling.NextSibling
 		} else {
 			node = node.NextSibling
@@ -898,9 +898,9 @@ func issueIndexPatternProcessor(ctx *RenderContext, node *html.Node) {
 				path = "pulls"
 			}
 			if ref.Owner == "" {
-				link = createLink(util.URLJoin(setting.AppURL, ctx.Metas["user"], ctx.Metas["repo"], path, ref.Issue), reftext, "ref-issue")
+				link = createLink(util.URLJoin(ctx.Links.Prefix(), ctx.Metas["user"], ctx.Metas["repo"], path, ref.Issue), reftext, "ref-issue")
 			} else {
-				link = createLink(util.URLJoin(setting.AppURL, ref.Owner, ref.Name, path, ref.Issue), reftext, "ref-issue")
+				link = createLink(util.URLJoin(ctx.Links.Prefix(), ref.Owner, ref.Name, path, ref.Issue), reftext, "ref-issue")
 			}
 		}
 
@@ -939,7 +939,7 @@ func commitCrossReferencePatternProcessor(ctx *RenderContext, node *html.Node) {
 		}
 
 		reftext := ref.Owner + "/" + ref.Name + "@" + base.ShortSha(ref.CommitSha)
-		link := createLink(util.URLJoin(setting.AppSubURL, ref.Owner, ref.Name, "commit", ref.CommitSha), reftext, "commit")
+		link := createLink(util.URLJoin(ctx.Links.Prefix(), ref.Owner, ref.Name, "commit", ref.CommitSha), reftext, "commit")
 
 		replaceContent(node, ref.RefLocation.Start, ref.RefLocation.End, link)
 		node = node.NextSibling.NextSibling
@@ -1166,7 +1166,7 @@ func hashCurrentPatternProcessor(ctx *RenderContext, node *html.Node) {
 			continue
 		}
 
-		link := util.URLJoin(setting.AppURL, ctx.Metas["user"], ctx.Metas["repo"], "commit", hash)
+		link := util.URLJoin(ctx.Links.Prefix(), ctx.Metas["user"], ctx.Metas["repo"], "commit", hash)
 		replaceContent(node, m[2], m[3], createCodeLink(link, base.ShortSha(hash), "commit"))
 		start = 0
 		node = node.NextSibling.NextSibling

modules/markup/renderer.go

@@ -82,9 +82,17 @@ type RenderContext struct {
 }
 
 type Links struct {
-	Base       string
-	BranchPath string
-	TreePath   string
+	AbsolutePrefix bool
+	Base           string
+	BranchPath     string
+	TreePath       string
+}
+
+func (l *Links) Prefix() string {
+	if l.AbsolutePrefix {
+		return setting.AppURL
+	}
+	return setting.AppSubURL
 }
 
 func (l *Links) HasBranchInfo() bool {

services/mailer/mail.go

@@ -222,7 +222,8 @@ func composeIssueCommentMessages(ctx *mailCommentContext, lang string, recipient
 	body, err := markdown.RenderString(&markup.RenderContext{
 		Ctx: ctx,
 		Links: markup.Links{
-			Base: ctx.Issue.Repo.HTMLURL(),
+			AbsolutePrefix: true,
+			Base:           ctx.Issue.Repo.HTMLURL(),
 		},
 		Metas: ctx.Issue.Repo.ComposeMetas(ctx),
 	}, ctx.Content)

services/mailer/mail_test.go

@@ -19,6 +19,7 @@ import (
 	repo_model "code.gitea.io/gitea/models/repo"
 	"code.gitea.io/gitea/models/unittest"
 	user_model "code.gitea.io/gitea/models/user"
+	"code.gitea.io/gitea/modules/markup"
 	"code.gitea.io/gitea/modules/setting"
 
 	"github.com/stretchr/testify/assert"
@@ -67,6 +68,12 @@ func prepareMailerTest(t *testing.T) (doer *user_model.User, repo *repo_model.Re
 func TestComposeIssueCommentMessage(t *testing.T) {
 	doer, _, issue, comment := prepareMailerTest(t)
 
+	markup.Init(&markup.ProcessorHelper{
+		IsUsernameMentionable: func(ctx context.Context, username string) bool {
+			return username == doer.Name
+		},
+	})
+
 	setting.IncomingEmail.Enabled = true
 	defer func() { setting.IncomingEmail.Enabled = false }()
 
@@ -77,7 +84,8 @@ func TestComposeIssueCommentMessage(t *testing.T) {
 	msgs, err := composeIssueCommentMessages(&mailCommentContext{
 		Context: context.TODO(), // TODO: use a correct context
 		Issue:   issue, Doer: doer, ActionType: activities_model.ActionCommentIssue,
-		Content: "test body", Comment: comment,
+		Content: fmt.Sprintf("test @%s %s#%d body", doer.Name, issue.Repo.FullName(), issue.Index),
+		Comment: comment,
 	}, "en-US", recipients, false, "issue comment")
 	assert.NoError(t, err)
 	assert.Len(t, msgs, 2)
@@ -96,6 +104,12 @@ func TestComposeIssueCommentMessage(t *testing.T) {
 	assert.Equal(t, "<user2/repo1/issues/1/comment/2@localhost>", gomailMsg.GetHeader("Message-ID")[0], "Message-ID header doesn't match")
 	assert.Equal(t, "<mailto:"+replyTo+">", gomailMsg.GetHeader("List-Post")[0])
 	assert.Len(t, gomailMsg.GetHeader("List-Unsubscribe"), 2) // url + mailto
+
+	var buf strings.Builder
+	gomailMsg.WriteTo(&buf)
+	mailMsg := strings.ReplaceAll(strings.ReplaceAll(buf.String(), "=", ""), "\r\n", "") // naïve quoted printable decoding, to allow string searching
+	assert.Contains(t, mailMsg, fmt.Sprintf("&#34;%s&#34;", doer.HTMLURL()))
+	assert.Contains(t, mailMsg, fmt.Sprintf("&#34;%s&#34;", issue.HTMLURL()))
 }
 
 func TestComposeIssueMessage(t *testing.T) {