Add rclone completion powershell - basic implementation only

cmd/genautocomplete/genautocomplete_powershell.go

@@ -0,0 +1,44 @@
+package genautocomplete
+
+import (
+	"log"
+	"os"
+
+	"github.com/rclone/rclone/cmd"
+	"github.com/spf13/cobra"
+)
+
+func init() {
+	completionDefinition.AddCommand(powershellCommandDefinition)
+}
+
+var powershellCommandDefinition = &cobra.Command{
+	Use:   "powershell [output_file]",
+	Short: `Output powershell completion script for rclone.`,
+	Long: `
+Generate the autocompletion script for powershell.
+
+To load completions in your current shell session:
+
+    rclone completion powershell | Out-String | Invoke-Expression
+
+To load completions for every new session, add the output of the above command
+to your powershell profile.
+
+If output_file is "-" or missing, then the output will be written to stdout.
+`,
+	Run: func(command *cobra.Command, args []string) {
+		cmd.CheckArgs(0, 1, command, args)
+		if len(args) == 0 || (len(args) > 0 && args[0] == "-") {
+			err := cmd.Root.GenPowerShellCompletion(os.Stdout)
+			if err != nil {
+				log.Fatal(err)
+			}
+			return
+		}
+		err := cmd.Root.GenPowerShellCompletionFile(args[0])
+		if err != nil {
+			log.Fatal(err)
+		}
+	},
+}