Link to tree views of submodules if possible

When linking a submodule at a commit in either the repo view, or a
diff when adding a new submodule, link to the tree view of that
submodules intead of the individual commit. This shows the user the
full tree, instead of the diff of the commit.

This makes the assumption that the tree for a given SHA is at
`<repo_url>/tree/<sha>`. This URL format is supported by both Github &
Gitlab, but not Gitea. To fix this, add a redirect from
`<username>/<repo>/tree/<ref>` to `<username>/<repo>/src/<ref>`.

Author: bohde

modules/git/commit_submodule_file.go

@@ -46,9 +46,9 @@ func (sf *CommitSubmoduleFile) SubmoduleWebLink(ctx context.Context, optCommitID
 	if len(optCommitID) == 2 {
 		commitLink = sf.repoLink + "/compare/" + optCommitID[0] + "..." + optCommitID[1]
 	} else if len(optCommitID) == 1 {
-		commitLink = sf.repoLink + "/commit/" + optCommitID[0]
+		commitLink = sf.repoLink + "/tree/" + optCommitID[0]
 	} else {
-		commitLink = sf.repoLink + "/commit/" + sf.refID
+		commitLink = sf.repoLink + "/tree/" + sf.refID
 	}
 	return &SubmoduleWebLink{RepoWebLink: sf.repoLink, CommitWebLink: commitLink}
 }

modules/git/commit_submodule_file_test.go

@@ -15,11 +15,11 @@ func TestCommitSubmoduleLink(t *testing.T) {
 
 	wl := sf.SubmoduleWebLink(context.Background())
 	assert.Equal(t, "https://github.com/user/repo", wl.RepoWebLink)
-	assert.Equal(t, "https://github.com/user/repo/commit/aaaa", wl.CommitWebLink)
+	assert.Equal(t, "https://github.com/user/repo/tree/aaaa", wl.CommitWebLink)
 
 	wl = sf.SubmoduleWebLink(context.Background(), "1111")
 	assert.Equal(t, "https://github.com/user/repo", wl.RepoWebLink)
-	assert.Equal(t, "https://github.com/user/repo/commit/1111", wl.CommitWebLink)
+	assert.Equal(t, "https://github.com/user/repo/tree/1111", wl.CommitWebLink)
 
 	wl = sf.SubmoduleWebLink(context.Background(), "1111", "2222")
 	assert.Equal(t, "https://github.com/user/repo", wl.RepoWebLink)

routers/web/web.go

@@ -5,6 +5,7 @@ package web
 
 import (
 	"net/http"
+	"path"
 	"strings"
 
 	auth_model "code.gitea.io/gitea/models/auth"
@@ -1584,6 +1585,18 @@ func registerRoutes(m *web.Router) {
 			m.Get("/*", context.RepoRefByType(""), repo.Home) // "/*" route is deprecated, and kept for backward compatibility
 		}, repo.SetEditorconfigIfExists)
 
+		// Add a /tree/* path to redirect to the deprecated /src/*
+		// path. This emulates both Github & Gitlab's URL structure.
+		m.Get("/tree/*", func(ctx *context.Context) {
+			prefix := "/"
+			if setting.AppSubURL != "" {
+				prefix = setting.AppSubURL
+			}
+
+			url := path.Join(prefix, ctx.PathParam("username"), ctx.PathParam("reponame"), "src", ctx.PathParam("*"))
+			ctx.Redirect(url)
+		})
+
 		m.Get("/forks", context.RepoRef(), repo.Forks)
 		m.Get("/commit/{sha:([a-f0-9]{7,64})}.{ext:patch|diff}", repo.MustBeNotEmpty, repo.RawDiff)
 		m.Post("/lastcommit/*", context.RepoRefByType(git.RefTypeCommit), repo.LastCommit)