Shallow clone submodules by default

docs.md

@@ -47,6 +47,7 @@ clone:
 | `tags`                    | `false` (except on tag event)       | Fetches tags when set to true, default is false if event is not tag else true                                                           |
 | `submodule_overrides`     | _none_                              | Override submodule urls                                                                                                                 |
 | `submodule_update_remote` | `false`                             | Pass the --remote flag to git submodule update                                                                                          |
+| `submodule_partial`       | `true`                              | Update submodules via partial clone (depth=1)                                                                                          |
 | `custom_ssl_path`         | _none_                              | Set path to custom cert                                                                                                                 |
 | `custom_ssl_url`          | _none_                              | Set url to custom cert                                                                                                                  |
 | `backoff`                 | `5sec`                              | Change backoff duration                                                                                                                 |

flags.go

@@ -91,6 +91,12 @@ var globalFlags = []cli.Flag{
 		EnvVars: []string{"PLUGIN_SUBMODULE_OVERRIDE"},
 		Value:   &MapFlag{},
 	},
+	&cli.BoolFlag{
+		Name:    "submodule-partial",
+		Usage:   "update submodules via partial clone (depth=1) (default)",
+		EnvVars: []string{"PLUGIN_SUBMODULES_PARTIAL", "PLUGIN_SUBMODULE_PARTIAL"},
+		Value:   true,
+	},
 	&cli.DurationFlag{
 		Name:    "backoff",
 		Usage:   "backoff duration",

main.go

@@ -45,20 +45,21 @@ func run(c *cli.Context) error {
 			Password: c.String("netrc.password"),
 		},
 		Config: Config{
-			Depth:           c.Int("depth"),
-			Tags:            c.Bool("tags"),
-			Recursive:       c.Bool("recursive"),
-			SkipVerify:      c.Bool("skip-verify"),
-			CustomCert:      c.String("custom-cert"),
-			SubmoduleRemote: c.Bool("submodule-update-remote"),
-			Submodules:      c.Generic("submodule-override").(*MapFlag).Get(),
-			Lfs:             c.Bool("lfs"),
-			Branch:          c.String("branch"),
-			Partial:         c.Bool("partial"),
-			Home:            c.String("home"),
-			SafeDirectory:   c.String("safe-directory"),
-			UseSSH:          c.Bool("use-ssh"),
-			SSHKey:          c.String("ssh-key"),
+			Depth:            c.Int("depth"),
+			Tags:             c.Bool("tags"),
+			Recursive:        c.Bool("recursive"),
+			SkipVerify:       c.Bool("skip-verify"),
+			CustomCert:       c.String("custom-cert"),
+			SubmoduleRemote:  c.Bool("submodule-update-remote"),
+			Submodules:       c.Generic("submodule-override").(*MapFlag).Get(),
+			SubmodulePartial: c.Bool("submodule-partial"),
+			Lfs:              c.Bool("lfs"),
+			Branch:           c.String("branch"),
+			Partial:          c.Bool("partial"),
+			Home:             c.String("home"),
+			SafeDirectory:    c.String("safe-directory"),
+			UseSSH:           c.Bool("use-ssh"),
+			SSHKey:           c.String("ssh-key"),
 		},
 		Backoff: Backoff{
 			Attempts: c.Int("backoff-attempts"),

plugin.go

@@ -92,7 +92,7 @@ func (p Plugin) Exec() error {
 	}
 
 	if p.Config.Recursive {
-		cmds = append(cmds, updateSubmodules(p.Config.SubmoduleRemote))
+		cmds = append(cmds, updateSubmodules(p.Config.SubmoduleRemote, p.Config.SubmodulePartial))
 	}
 
 	if p.Config.Lfs {
@@ -295,14 +295,12 @@ func fetch(ref string, tags bool, depth int, filter string) *exec.Cmd {
 }
 
 // updateSubmodules recursively initializes and updates submodules.
-func updateSubmodules(remote bool) *exec.Cmd {
-	cmd := exec.Command(
-		"git",
-		"submodule",
-		"update",
-		"--init",
-		"--recursive",
-	)
+func updateSubmodules(remote, partial bool) *exec.Cmd {
+	args := []string{"submodule", "update", "--init", "--recursive"}
+	if partial {
+		args = append(args, "--depth=1", "--recommend-shallow")
+	}
+	cmd := exec.Command("git", args...)
 
 	if remote {
 		cmd.Args = append(cmd.Args, "--remote")

plugin_test.go

@@ -278,11 +278,11 @@ func TestFetch(t *testing.T) {
 // are constructed properly.
 func TestUpdateSubmodules(t *testing.T) {
 	testdata := []struct {
-		depth int
-		exp   []string
+		partial bool
+		exp     []string
 	}{
 		{
-			50,
+			false,
 			[]string{
 				"git",
 				"submodule",
@@ -292,18 +292,20 @@ func TestUpdateSubmodules(t *testing.T) {
 			},
 		},
 		{
-			100,
+			true,
 			[]string{
 				"git",
 				"submodule",
 				"update",
 				"--init",
 				"--recursive",
+				"--depth=1",
+				"--recommend-shallow",
 			},
 		},
 	}
 	for _, td := range testdata {
-		c := updateSubmodules(false)
+		c := updateSubmodules(false, td.partial)
 		if len(c.Args) != len(td.exp) {
 			t.Errorf("Expected: %s, got %s", td.exp, c.Args)
 		}
@@ -374,11 +376,9 @@ func TestCustomCertFile(t *testing.T) {
 // are constructed properly.
 func TestUpdateSubmodulesRemote(t *testing.T) {
 	testdata := []struct {
-		depth int
-		exp   []string
+		exp []string
 	}{
 		{
-			50,
 			[]string{
 				"git",
 				"submodule",
@@ -389,7 +389,6 @@ func TestUpdateSubmodulesRemote(t *testing.T) {
 			},
 		},
 		{
-			100,
 			[]string{
 				"git",
 				"submodule",
@@ -401,7 +400,7 @@ func TestUpdateSubmodulesRemote(t *testing.T) {
 		},
 	}
 	for _, td := range testdata {
-		c := updateSubmodules(true)
+		c := updateSubmodules(true, false)
 		if len(c.Args) != len(td.exp) {
 			t.Errorf("Expected: %s, got %s", td.exp, c.Args)
 		}

types.go

@@ -26,21 +26,22 @@ type (
 	}
 
 	Config struct {
-		Depth           int
-		Recursive       bool
-		SkipVerify      bool
-		Tags            bool
-		Submodules      map[string]string
-		SubmoduleRemote bool
-		CustomCert      string
-		Lfs             bool
-		Branch          string
-		Home            string
-		Partial         bool
-		filter          string
-		SafeDirectory   string
-		UseSSH          bool
-		SSHKey          string
+		Depth            int
+		Recursive        bool
+		SkipVerify       bool
+		Tags             bool
+		Submodules       map[string]string
+		SubmoduleRemote  bool
+		SubmodulePartial bool
+		CustomCert       string
+		Lfs              bool
+		Branch           string
+		Home             string
+		Partial          bool
+		filter           string
+		SafeDirectory    string
+		UseSSH           bool
+		SSHKey           string
 	}
 
 	Backoff struct {