From 5117caca450c94bb1d1760f175d9e5720d88b510 Mon Sep 17 00:00:00 2001
From: Andrew Thornton <art27@cantab.net>
Date: Sun, 21 Mar 2021 15:45:04 +0000
Subject: [PATCH 1/3] Links in markdown should be absolute to the repository
 not the server

Fix #15075

Signed-off-by: Andrew Thornton <art27@cantab.net>
---
 modules/markup/markdown/goldmark.go | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/modules/markup/markdown/goldmark.go b/modules/markup/markdown/goldmark.go
index 07e2e36e1da4..ac30893006ef 100644
--- a/modules/markup/markdown/goldmark.go
+++ b/modules/markup/markdown/goldmark.go
@@ -7,6 +7,7 @@ package markdown
 import (
 	"bytes"
 	"fmt"
+	"path"
 	"regexp"
 	"strings"
 
@@ -99,6 +100,8 @@ func (g *ASTTransformer) Transform(node *ast.Document, reader text.Reader, pc pa
 				prefix = strings.Replace(prefix, "/src/", "/media/", 1)
 
 				lnk := string(link)
+				lnk = path.Clean("/" + lnk)[1:]
+
 				lnk = giteautil.URLJoin(prefix, lnk)
 				link = []byte(lnk)
 			}

From 2da4391980097276d6824a3dcab9f0a8abf65c27 Mon Sep 17 00:00:00 2001
From: Andrew Thornton <art27@cantab.net>
Date: Thu, 25 Mar 2021 19:44:24 +0000
Subject: [PATCH 2/3] match github

Signed-off-by: Andrew Thornton <art27@cantab.net>
---
 modules/markup/markdown/goldmark.go | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/modules/markup/markdown/goldmark.go b/modules/markup/markdown/goldmark.go
index ac30893006ef..ad77177db439 100644
--- a/modules/markup/markdown/goldmark.go
+++ b/modules/markup/markdown/goldmark.go
@@ -7,7 +7,6 @@ package markdown
 import (
 	"bytes"
 	"fmt"
-	"path"
 	"regexp"
 	"strings"
 
@@ -99,8 +98,7 @@ func (g *ASTTransformer) Transform(node *ast.Document, reader text.Reader, pc pa
 				}
 				prefix = strings.Replace(prefix, "/src/", "/media/", 1)
 
-				lnk := string(link)
-				lnk = path.Clean("/" + lnk)[1:]
+				lnk := strings.TrimLeft(string(link), "/")
 
 				lnk = giteautil.URLJoin(prefix, lnk)
 				link = []byte(lnk)

From 8c313651315c0df9063a4cd985353ad877a3fd91 Mon Sep 17 00:00:00 2001
From: Andrew Thornton <art27@cantab.net>
Date: Thu, 25 Mar 2021 19:58:38 +0000
Subject: [PATCH 3/3] add testcase

Signed-off-by: Andrew Thornton <art27@cantab.net>
---
 modules/markup/markdown/markdown_test.go | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/modules/markup/markdown/markdown_test.go b/modules/markup/markdown/markdown_test.go
index 5b3ef21fb66b..0e340763aedd 100644
--- a/modules/markup/markdown/markdown_test.go
+++ b/modules/markup/markdown/markdown_test.go
@@ -93,6 +93,19 @@ func TestRender_Images(t *testing.T) {
 	test(
 		"[!["+title+"]("+url+")]("+href+")",
 		`<p><a href="`+href+`" rel="nofollow"><img src="`+result+`" alt="`+title+`"/></a></p>`)
+
+	url = "/../../.images/src/02/train.jpg"
+	test(
+		"!["+title+"]("+url+")",
+		`<p><a href="`+result+`" rel="nofollow"><img src="`+result+`" alt="`+title+`"/></a></p>`)
+
+	test(
+		"[["+title+"|"+url+"]]",
+		`<p><a href="`+result+`" rel="nofollow"><img src="`+result+`" title="`+title+`" alt="`+title+`"/></a></p>`)
+	test(
+		"[!["+title+"]("+url+")]("+href+")",
+		`<p><a href="`+href+`" rel="nofollow"><img src="`+result+`" alt="`+title+`"/></a></p>`)
+
 }
 
 func testAnswers(baseURLContent, baseURLImages string) []string {