refactor: move fields into CmdOutputOpts, warn on plaintext --fields

Remove the standalone `fields []string` positional parameter from
CmdOutput and pass fields exclusively through CmdOutputOpts.Fields.
This eliminates the dual-path API and simplifies every call site.

Also emit a stderr warning when --fields is used with plaintext output,
since the flag is silently ignored in that mode.

Made-with: Cursor

Author: nieblara

cmd/config/config.go

@@ -287,7 +287,7 @@ func outputSetAction(newFields []string) (string, error) {
 		Items: newFields,
 	}
 	fieldsJSON, _ := json.Marshal(fields)
-	output, err := output.CmdOutput("update", viper.GetString(cliflags.OutputFlag), fieldsJSON, nil)
+	output, err := output.CmdOutput("update", viper.GetString(cliflags.OutputFlag), fieldsJSON)
 	if err != nil {
 		return "", errs.NewError(err.Error())
 	}
@@ -302,7 +302,7 @@ func outputUnsetAction(newField string) (string, error) {
 		Key: newField,
 	}
 	fieldJSON, _ := json.Marshal(field)
-	output, err := output.CmdOutput("delete", viper.GetString(cliflags.OutputFlag), fieldJSON, nil)
+	output, err := output.CmdOutput("delete", viper.GetString(cliflags.OutputFlag), fieldJSON)
 	if err != nil {
 		return "", errs.NewError(err.Error())
 	}

cmd/flags/archive.go

@@ -51,7 +51,8 @@ func makeArchiveRequest(client resources.Client) func(*cobra.Command, []string)
 			return output.NewCmdOutputError(err, cliflags.GetOutputKind(cmd))
 		}
 
-		output, err := output.CmdOutput("update", cliflags.GetOutputKind(cmd), res, cliflags.GetFields(cmd), output.CmdOutputOpts{
+		output, err := output.CmdOutput("update", cliflags.GetOutputKind(cmd), res, output.CmdOutputOpts{
+			Fields:       cliflags.GetFields(cmd),
 			ResourceName: "flags",
 		})
 		if err != nil {

cmd/flags/toggle.go

@@ -73,7 +73,8 @@ func runE(client resources.Client) func(*cobra.Command, []string) error {
 			return output.NewCmdOutputError(err, cliflags.GetOutputKind(cmd))
 		}
 
-		output, err := output.CmdOutput("update", cliflags.GetOutputKind(cmd), res, cliflags.GetFields(cmd), output.CmdOutputOpts{
+		output, err := output.CmdOutput("update", cliflags.GetOutputKind(cmd), res, output.CmdOutputOpts{
+			Fields:       cliflags.GetFields(cmd),
 			ResourceName: "flags",
 		})
 		if err != nil {

cmd/members/invite.go

@@ -63,7 +63,8 @@ func runE(client resources.Client) func(*cobra.Command, []string) error {
 			return output.NewCmdOutputError(err, cliflags.GetOutputKind(cmd))
 		}
 
-		output, err := output.CmdOutput("update", cliflags.GetOutputKind(cmd), res, cliflags.GetFields(cmd), output.CmdOutputOpts{
+		output, err := output.CmdOutput("update", cliflags.GetOutputKind(cmd), res, output.CmdOutputOpts{
+			Fields:       cliflags.GetFields(cmd),
 			ResourceName: "members",
 		})
 		if err != nil {

cmd/resources/resources.go

@@ -349,7 +349,8 @@ func (op *OperationCmd) makeRequest(cmd *cobra.Command, args []string) error {
 		res = []byte(fmt.Sprintf(`{"key": %q}`, urlParms[len(urlParms)-1]))
 	}
 
-	output, err := output.CmdOutput(cmd.Use, cliflags.GetOutputKind(cmd), res, cliflags.GetFields(cmd), output.CmdOutputOpts{
+	output, err := output.CmdOutput(cmd.Use, cliflags.GetOutputKind(cmd), res, output.CmdOutputOpts{
+		Fields:       cliflags.GetFields(cmd),
 		ResourceName: cmd.Parent().Name(),
 	})
 	if err != nil {

internal/output/resource_output.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"math"
 	"net/url"
+	"os"
 	"strconv"
 	"strings"
 
@@ -19,16 +20,17 @@ type CmdOutputOpts struct {
 }
 
 // CmdOutput returns a response from a resource action formatted based on the output flag along with
-// an optional message based on the action. When fields is non-empty and outputKind is "json",
-// only the specified top-level fields are included in the output. When resourceName matches a
+// an optional message based on the action. When opts.Fields is non-empty and outputKind is "json",
+// only the specified top-level fields are included in the output. When opts.ResourceName matches a
 // registered resource, list output uses table formatting and singular output uses key-value pairs.
-func CmdOutput(action string, outputKind string, input []byte, fields []string, opts ...CmdOutputOpts) (string, error) {
-	var resourceName string
+func CmdOutput(action string, outputKind string, input []byte, opts ...CmdOutputOpts) (string, error) {
+	var (
+		fields       []string
+		resourceName string
+	)
 	if len(opts) > 0 {
 		resourceName = opts[0].ResourceName
-		if len(fields) == 0 {
-			fields = opts[0].Fields
-		}
+		fields = opts[0].Fields
 	}
 
 	if outputKind == "json" {
@@ -42,6 +44,10 @@ func CmdOutput(action string, outputKind string, input []byte, fields []string,
 		return string(input), nil
 	}
 
+	if len(fields) > 0 {
+		fmt.Fprintln(os.Stderr, "note: --fields is only supported with JSON output; ignoring")
+	}
+
 	var (
 		maybeResource      resource
 		maybeResources     resources