Fix footnote jump behavior on the issue page.

Author: charles7668

modules/markup/html.go

@@ -320,6 +320,8 @@ func visitNode(ctx *RenderContext, procs []processor, node *html.Node) *html.Nod
 	}
 
 	processNodeAttrID(node)
+	processFootnoteID(ctx, node)
+	processFootnoteBackHref(ctx, node)
 
 	if isEmojiNode(node) {
 		// TextNode emoji will be converted to `<span class="emoji">`, then the next iteration will visit the "span"

modules/markup/html_node.go

@@ -15,6 +15,14 @@ func isAnchorIDUserContent(s string) bool {
 	return strings.HasPrefix(s, "user-content-") || strings.Contains(s, ":user-content-")
 }
 
+func isAnchorIDFootnote(s string) bool {
+	return strings.HasPrefix(s, "fnref:user-content-")
+}
+
+func isAnchorHrefFootnote(s string) bool {
+	return strings.HasPrefix(s, "#fnref:user-content-")
+}
+
 func processNodeAttrID(node *html.Node) {
 	// Add user-content- to IDs and "#" links if they don't already have them,
 	// and convert the link href to a relative link to the host root
@@ -27,6 +35,32 @@ func processNodeAttrID(node *html.Node) {
 	}
 }
 
+func processFootnoteID(ctx *RenderContext, node *html.Node) {
+	for idx, attr := range node.Attr {
+		if attr.Key == "id" {
+			if !isAnchorIDFootnote(attr.Val) {
+				return
+			}
+			if issueNum, ok := ctx.RenderOptions.Metas["issue_comment_id"]; ok {
+				node.Attr[idx].Val = attr.Val + "-" + issueNum
+			}
+		}
+	}
+}
+
+func processFootnoteBackHref(ctx *RenderContext, node *html.Node) {
+	for idx, attr := range node.Attr {
+		if attr.Key == "href" {
+			if !isAnchorHrefFootnote(attr.Val) {
+				return
+			}
+			if issueNum, ok := ctx.RenderOptions.Metas["issue_comment_id"]; ok {
+				node.Attr[idx].Val = attr.Val + "-" + issueNum
+			}
+		}
+	}
+}
+
 func processNodeA(ctx *RenderContext, node *html.Node) {
 	for idx, attr := range node.Attr {
 		if attr.Key == "href" {

routers/web/repo/issue_view.go

@@ -9,6 +9,7 @@ import (
 	"net/http"
 	"net/url"
 	"sort"
+	"strconv"
 
 	activities_model "code.gitea.io/gitea/models/activities"
 	"code.gitea.io/gitea/models/db"
@@ -625,6 +626,7 @@ func prepareIssueViewCommentsAndSidebarParticipants(ctx *context.Context, issue
 
 		if comment.Type == issues_model.CommentTypeComment || comment.Type == issues_model.CommentTypeReview {
 			rctx := renderhelper.NewRenderContextRepoComment(ctx, issue.Repo)
+			rctx.RenderOptions.Metas["issue_comment_id"] = strconv.FormatInt(comment.ID, 10)
 			comment.RenderedContent, err = markdown.RenderString(rctx, comment.Content)
 			if err != nil {
 				ctx.ServerError("RenderString", err)
@@ -982,6 +984,8 @@ func preparePullViewReviewAndMerge(ctx *context.Context, issue *issues_model.Iss
 func prepareIssueViewContent(ctx *context.Context, issue *issues_model.Issue) {
 	var err error
 	rctx := renderhelper.NewRenderContextRepoComment(ctx, ctx.Repo.Repository)
+	// the first issue index set to 0
+	rctx.RenderOptions.Metas["issue_comment_id"] = "0"
 	issue.RenderedContent, err = markdown.RenderString(rctx, issue.Content)
 	if err != nil {
 		ctx.ServerError("RenderString", err)