Refactor SSH clone URL generation code (#28421)

Refactor the code and add tests, keep the old logic.

models/repo/repo.go

@@ -606,25 +606,23 @@ func ComposeHTTPSCloneURL(owner, repo string) string {
 
 func ComposeSSHCloneURL(ownerName, repoName string) string {
 	sshUser := setting.SSH.User
-
-	// if we have a ipv6 literal we need to put brackets around it
-	// for the git cloning to work.
 	sshDomain := setting.SSH.Domain
-	ip := net.ParseIP(setting.SSH.Domain)
-	if ip != nil && ip.To4() == nil {
-		sshDomain = "[" + setting.SSH.Domain + "]"
-	}
 
+	// non-standard port, it must use full URI
 	if setting.SSH.Port != 22 {
-		return fmt.Sprintf("ssh://%s@%s/%s/%s.git", sshUser,
-			net.JoinHostPort(setting.SSH.Domain, strconv.Itoa(setting.SSH.Port)),
-			url.PathEscape(ownerName),
-			url.PathEscape(repoName))
+		sshHost := net.JoinHostPort(sshDomain, strconv.Itoa(setting.SSH.Port))
+		return fmt.Sprintf("ssh://%s@%s/%s/%s.git", sshUser, sshHost, url.PathEscape(ownerName), url.PathEscape(repoName))
+	}
+
+	// for standard port, it can use a shorter URI (without the port)
+	sshHost := sshDomain
+	if ip := net.ParseIP(sshHost); ip != nil && ip.To4() == nil {
+		sshHost = "[" + sshHost + "]" // for IPv6 address, wrap it with brackets
 	}
 	if setting.Repository.UseCompatSSHURI {
-		return fmt.Sprintf("ssh://%s@%s/%s/%s.git", sshUser, sshDomain, url.PathEscape(ownerName), url.PathEscape(repoName))
+		return fmt.Sprintf("ssh://%s@%s/%s/%s.git", sshUser, sshHost, url.PathEscape(ownerName), url.PathEscape(repoName))
 	}
-	return fmt.Sprintf("%s@%s:%s/%s.git", sshUser, sshDomain, url.PathEscape(ownerName), url.PathEscape(repoName))
+	return fmt.Sprintf("%s@%s:%s/%s.git", sshUser, sshHost, url.PathEscape(ownerName), url.PathEscape(repoName))
 }
 
 func (repo *Repository) cloneLink(isWiki bool) *CloneLink {

models/repo/repo_test.go

@@ -12,6 +12,8 @@ import (
 	"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"
+	"code.gitea.io/gitea/modules/test"
 	"code.gitea.io/gitea/modules/util"
 
 	"github.com/stretchr/testify/assert"
@@ -186,3 +188,32 @@ func TestGetRepositoryByURL(t *testing.T) {
 		test(t, "try.gitea.io:user2/repo2.git")
 	})
 }
+
+func TestComposeSSHCloneURL(t *testing.T) {
+	defer test.MockVariableValue(&setting.SSH, setting.SSH)()
+	defer test.MockVariableValue(&setting.Repository, setting.Repository)()
+
+	setting.SSH.User = "git"
+
+	// test SSH_DOMAIN
+	setting.SSH.Domain = "domain"
+	setting.SSH.Port = 22
+	setting.Repository.UseCompatSSHURI = false
+	assert.Equal(t, "git@domain:user/repo.git", repo_model.ComposeSSHCloneURL("user", "repo"))
+	setting.Repository.UseCompatSSHURI = true
+	assert.Equal(t, "ssh://git@domain/user/repo.git", repo_model.ComposeSSHCloneURL("user", "repo"))
+	// test SSH_DOMAIN while use non-standard SSH port
+	setting.SSH.Port = 123
+	setting.Repository.UseCompatSSHURI = false
+	assert.Equal(t, "ssh://git@domain:123/user/repo.git", repo_model.ComposeSSHCloneURL("user", "repo"))
+	setting.Repository.UseCompatSSHURI = true
+	assert.Equal(t, "ssh://git@domain:123/user/repo.git", repo_model.ComposeSSHCloneURL("user", "repo"))
+
+	// test IPv6 SSH_DOMAIN
+	setting.Repository.UseCompatSSHURI = false
+	setting.SSH.Domain = "::1"
+	setting.SSH.Port = 22
+	assert.Equal(t, "git@[::1]:user/repo.git", repo_model.ComposeSSHCloneURL("user", "repo"))
+	setting.SSH.Port = 123
+	assert.Equal(t, "ssh://git@[::1]:123/user/repo.git", repo_model.ComposeSSHCloneURL("user", "repo"))
+}