Squashed commit of the following:

commit ef441ca
Merge: dda3fd1 1dbd729
Author: matej.risek <matej.risek@hashicorp.com>
Date:   Mon May 8 14:56:31 2023 +0200

    Merge branch 'master' into fix/scp-style-submodule-url

    # Conflicts:
    #	submodule_test.go

commit dda3fd1
Merge: 6785da7 da73c5f
Author: matej.risek <matej.risek@hashicorp.com>
Date:   Mon May 8 14:55:31 2023 +0200

    Merge branch 'master' into fix/scp-style-submodule-url

commit 6785da7
Author: matej.risek <matej.risek@hashicorp.com>
Date:   Wed May 3 14:56:32 2023 +0200

    git: fix the issue with submodules having the SCP style URL fail due to the wrong URL parsing

submodule.go

@@ -5,13 +5,13 @@ import (
 	"context"
 	"errors"
 	"fmt"
-	"net/url"
 	"path"
 
 	"github.com/go-git/go-billy/v5"
 	"github.com/go-git/go-git/v5/config"
 	"github.com/go-git/go-git/v5/plumbing"
 	"github.com/go-git/go-git/v5/plumbing/format/index"
+	"github.com/go-git/go-git/v5/plumbing/transport"
 )
 
 var (
@@ -133,29 +133,29 @@ func (s *Submodule) Repository() (*Repository, error) {
 		return nil, err
 	}
 
-	moduleURL, err := url.Parse(s.c.URL)
+	moduleEndpoint, err := transport.NewEndpoint(s.c.URL)
 	if err != nil {
 		return nil, err
 	}
 
-	if !path.IsAbs(moduleURL.Path) {
+	if !path.IsAbs(moduleEndpoint.Path) && moduleEndpoint.Protocol == "file" {
 		remotes, err := s.w.r.Remotes()
 		if err != nil {
 			return nil, err
 		}
 
-		rootURL, err := url.Parse(remotes[0].c.URLs[0])
+		rootEndpoint, err := transport.NewEndpoint(remotes[0].c.URLs[0])
 		if err != nil {
 			return nil, err
 		}
 
-		rootURL.Path = path.Join(rootURL.Path, moduleURL.Path)
-		*moduleURL = *rootURL
+		rootEndpoint.Path = path.Join(rootEndpoint.Path, moduleEndpoint.Path)
+		*moduleEndpoint = *rootEndpoint
 	}
 
 	_, err = r.CreateRemote(&config.RemoteConfig{
 		Name: DefaultRemoteName,
-		URLs: []string{moduleURL.String()},
+		URLs: []string{moduleEndpoint.String()},
 	})
 
 	return r, err

submodule_test.go

@@ -6,7 +6,10 @@ import (
 	"path/filepath"
 	"testing"
 
+	"github.com/go-git/go-billy/v5/memfs"
+	"github.com/go-git/go-git/v5/config"
 	"github.com/go-git/go-git/v5/plumbing"
+	"github.com/go-git/go-git/v5/storage/memory"
 
 	fixtures "github.com/go-git/go-git-fixtures/v4"
 	. "gopkg.in/check.v1"
@@ -262,3 +265,26 @@ func (s *SubmoduleSuite) TestSubmodulesFetchDepth(c *C) {
 
 	c.Assert(commitCount, Equals, 1)
 }
+
+func (s *SubmoduleSuite) TestSubmoduleParseScp(c *C) {
+	repo := &Repository{
+		Storer: memory.NewStorage(),
+		wt:     memfs.New(),
+	}
+	worktree := &Worktree{
+		Filesystem: memfs.New(),
+		r:          repo,
+	}
+	submodule := &Submodule{
+		initialized: true,
+		c:           nil,
+		w:           worktree,
+	}
+
+	submodule.c = &config.Submodule{
+		URL: "git@github.com:username/submodule_repo",
+	}
+
+	_, err := submodule.Repository()
+	c.Assert(err, IsNil)
+}