refactor(output): share the JSON, created-resource and batch tails

Mutations end with a.jsonResult or a.created instead of hand-rolled
--json branches, the two identical jsonResult/writeMutationJSON helpers
become one, and writeBatchJSON checks --json itself so batch commands
share one tail.

Signed-off-by: bircni <bircni@icloud.com>

internal/app/human_output.go

@@ -149,12 +149,20 @@ func (a *application) feedback(cmd *cobra.Command, icon, color, format string, a
 	fmt.Fprintln(cmd.ErrOrStderr(), terminal.Colorize(color, icon, a.colorEnabled())+" "+terminal.SafeLine(fmt.Sprintf(format, args...)))
 }
 
-// printURL writes the URL of a created resource to stdout unless --json is set, so scripts can
-// capture it: url=$(tea issue create …).
-func (a *application) printURL(cmd *cobra.Command, url string) error {
-	if a.options.json != "" {
+// jsonResult writes the result of a mutation when --json asks for it; people get a done line instead.
+func (a *application) jsonResult(cmd *cobra.Command, item any) error {
+	if a.options.json == "" {
 		return nil
 	}
+	return a.writeJSON(cmd, item)
+}
+
+// created writes a created resource as JSON with --json, else its URL to stdout, so scripts can
+// capture it: url=$(tea issue create …).
+func (a *application) created(cmd *cobra.Command, item any, url string) error {
+	if a.options.json != "" {
+		return a.writeJSON(cmd, item)
+	}
 	_, err := fmt.Fprintln(cmd.OutOrStdout(), terminal.SafeLine(url))
 	return err
 }
@@ -170,7 +178,7 @@ type abortBatch struct{ error }
 func (e abortBatch) Unwrap() error { return e.error }
 
 // applyBatch applies run to each selection and continues past individual failures, which it
-// returns prefixed with the selection's label. succeeded sees each result as it arrives.
+// returns prefixed with the selection's label. succeeded, when set, sees each result as it arrives.
 func applyBatch[K, T any](cmd *cobra.Command, keys []K, label func(K) string, run func(K) (T, error), succeeded func(T)) ([]T, []error) {
 	results := []T{}
 	var failures []error
@@ -189,14 +197,18 @@ func applyBatch[K, T any](cmd *cobra.Command, keys []K, label func(K) string, ru
 			continue
 		}
 		results = append(results, item)
-		succeeded(item)
+		if succeeded != nil {
+			succeeded(item)
+		}
 	}
 	return results, failures
 }
 
-// writeBatchJSON writes an object for one selection (none if it failed), otherwise an array.
+// writeBatchJSON writes, with --json, an object for one selection (none if it failed), otherwise an array.
 func writeBatchJSON[T any](a *application, cmd *cobra.Command, selections int, results []T) error {
 	switch {
+	case a.options.json == "":
+		return nil
 	case selections != 1:
 		return a.writeJSON(cmd, results)
 	case len(results) == 1:
@@ -209,11 +221,7 @@ func writeBatchJSON[T any](a *application, cmd *cobra.Command, selections int, r
 // line from report, such as "Closed issue alice/x#5 (Fix login)", and the results as JSON.
 func batchDone[K, T any](a *application, cmd *cobra.Command, keys []K, label func(K) string, run func(K) (T, error), report func(T) string) error {
 	results, failures := applyBatch(cmd, keys, label, run, func(item T) { a.done(cmd, "%s", report(item)) })
-	var err error
-	if a.options.json != "" {
-		err = writeBatchJSON(a, cmd, len(keys), results)
-	}
-	return errors.Join(append(failures, err)...)
+	return errors.Join(append(failures, writeBatchJSON(a, cmd, len(keys), results))...)
 }
 
 // stateColors colors issue, pull request and milestone states with the terminal's own palette.