podman network ls: use report.Formatter over Template

Currently the podman command --format output code uses a mix of
report.Formatter and report.Template.

I patched report.Formatter to correctly handle newlines[1]. Since we
cannot fix this with report.Template we have to migrate all users to
report.Formatter. This ensures consistent behavior for all commands.

This change does not change the output, we can add a new test for the
newline bug when the common PR is vendored in.

[1] containers/common#1146

Signed-off-by: Paul Holzinger <[email protected]>

cmd/podman/networks/list.go

@@ -122,36 +122,27 @@ func templateOut(cmd *cobra.Command, responses []types.Network) error {
 		"ID":     "network id",
 	})
 
-	renderHeaders := report.HasTable(networkListOptions.Format)
-	var row string
+	rpt := report.New(os.Stdout, cmd.Name())
+	defer rpt.Flush()
+
+	var err error
 	switch {
-	case cmd.Flags().Changed("format"):
-		row = report.NormalizeFormat(networkListOptions.Format)
+	case cmd.Flag("format").Changed:
+		rpt, err = rpt.Parse(report.OriginUser, networkListOptions.Format)
 	default:
-		// 'podman network ls' equivalent to 'podman network ls --format="table {{.ID}} {{.Name}} {{.Version}} {{.Plugins}}" '
-		row = "{{.ID}}\t{{.Name}}\t{{.Driver}}\n"
-		renderHeaders = true
+		rpt, err = rpt.Parse(report.OriginPodman, "{{range .}}{{.ID}}\t{{.Name}}\t{{.Driver}}\n{{end -}}")
 	}
-	format := report.EnforceRange(row)
-
-	tmpl, err := report.NewTemplate("list").Parse(format)
-	if err != nil {
-		return err
-	}
-
-	w, err := report.NewWriterDefault(os.Stdout)
 	if err != nil {
 		return err
 	}
-	defer w.Flush()
 
 	noHeading, _ := cmd.Flags().GetBool("noheading")
-	if !noHeading && renderHeaders {
-		if err := tmpl.Execute(w, headers); err != nil {
-			return err
+	if rpt.RenderHeaders && !noHeading {
+		if err := rpt.Execute(headers); err != nil {
+			return fmt.Errorf("failed to write report column headers: %w", err)
 		}
 	}
-	return tmpl.Execute(w, nlprs)
+	return rpt.Execute(nlprs)
 }
 
 // ListPrintReports returns the network list report