Updated review comments :)

pkg/plugin/hooks.go

@@ -21,7 +21,7 @@ const (
 	Install = "install"
 	// Delete is executed after the plugin is removed.
 	Delete = "delete"
-	// Update is executed after the plugin is removed.
+	// Update is executed after the plugin is updated.
 	Update = "update"
 )
 

pkg/plugin/installer/installer.go

@@ -49,10 +49,10 @@ func Install(i Installer) error {
 	return i.Install()
 }
 
-// Update updates a plugin to $HELM_HOME.
+// Update updates a plugin in $HELM_HOME.
 func Update(i Installer) error {
 	if _, pathErr := os.Stat(i.Path()); os.IsNotExist(pathErr) {
-		return errors.New("plugin does not exists")
+		return errors.New("plugin does not exist")
 	}
 
 	return i.Update()

pkg/plugin/installer/vcs_installer_test.go

@@ -107,9 +107,9 @@ func TestVCSInstaller(t *testing.T) {
 
 	// Testing update for error
 	if err := Update(i); err == nil {
-		t.Error("expected error for plugin does not exists, got none")
-	} else if err.Error() != "plugin does not exists" {
-		t.Errorf("expected error for plugin does not exists, got (%v)", err)
+		t.Error("expected error for plugin does not exist, got none")
+	} else if err.Error() != "plugin does not exist" {
+		t.Errorf("expected error for plugin does not exist, got (%v)", err)
 	}
 }
 
@@ -172,9 +172,9 @@ func TestVCSInstallerUpdate(t *testing.T) {
 	}
 
 	if err := Update(i); err == nil {
-		t.Error("expected error for plugin does not exists, got none")
-	} else if err.Error() != "plugin does not exists" {
-		t.Errorf("expected error for plugin does not exists, got (%v)", err)
+		t.Error("expected error for plugin does not exist, got none")
+	} else if err.Error() != "plugin does not exist" {
+		t.Errorf("expected error for plugin does not exist, got (%v)", err)
 	}
 
 	// Install plugin before update