feat: add JSON output to taskrun delete

[Debashich]

Changes

Part of #2850

Add consistent -o/--output json support to taskrun delete, including machine-readable output of successfully deleted TaskRuns. Interactive confirmation prompts are suppressed when JSON output is requested.

Extend the shared deleter package with accessors for successful and related deletions, with corresponding unit tests.

Verified the relevant TaskRun delete/list output paths and existing test coverage. go test ./pkg/cmd/taskrun ./pkg/deleter passes.

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[Copilot]

Pull request overview

This PR adds -o/--output json support to tkn taskrun delete, enabling machine-readable output of deleted TaskRuns and extending the shared pkg/deleter helper with accessors for successful deletions (plus unit tests).

Changes:

• Added JSON output path for taskrun delete, and suppressed interactive confirmation when JSON is requested.
• Extended pkg/deleter with accessors for successful deletes / related deletes.
• Added unit tests for the new deleter accessors and JSON output for taskrun delete.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 7 comments.

File	Description
pkg/deleter/deleter.go	Adds accessors for successful deletes and successful related deletes.
pkg/deleter/deleter_test.go	Adds unit tests validating the new deleter accessors.
pkg/cmd/taskrun/delete.go	Implements JSON output mode and adjusts delete flow to suppress prompts in JSON mode.
pkg/cmd/taskrun/delete_test.go	Adds tests asserting JSON output for taskrun delete.

Suppressed comments (1)

pkg/deleter/deleter.go:113

• SuccessfulRelatedDeletes also returns the backing slice directly, which allows external mutation of Deleter state. Returning a copy prevents subtle bugs when callers append/modify the returned slice.

func (d *Deleter) SuccessfulRelatedDeletes() []string {
	return d.successfulRelatedDeletes
}

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[Copilot]

Pull request overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated no new comments.

Suppressed comments (5)

pkg/cmd/taskrun/delete.go:135

• JSON mode skips CheckOptions entirely, but that method performs validation before prompting. As a result, -o json accepts invalid destructive combinations such as named TaskRuns with --all/--keep, and even an invocation with neither names nor --all succeeds with an empty result. Keep the validation and suppress only the confirmation prompt.

			if output != "json" {
				if err := opts.CheckOptions(s, availableTrs, p.Namespace()); err != nil {
					return err
				}
			}

pkg/cmd/taskrun/delete.go:190

• With --force -o json, a TaskRun owned by a running PipelineRun writes this warning to stdout before the JSON document, making stdout invalid JSON. Send the warning to stderr so stdout remains machine-readable.

			if !prFinished && !opts.ForceDelete && output != "json" {

pkg/cmd/taskrun/delete.go:240

• This returns success immediately after encoding and drops any deletion errors accumulated by Deleter. A delete that fails after lookup (for example, due to a race or API error) is therefore reported as a successful command with only the failed name omitted; encode the result, then return d.Errors().

		return json.NewEncoder(s.Out).Encode(result)

pkg/cmd/taskrun/delete.go:233

• The JSON branch is unreachable for the two no-op --task --keep cases above because they return after printing human-readable status text. For example, when --keep equals the number of matching TaskRuns, -o json does not produce JSON at all. Route those early exits through the JSON renderer and return an empty deleted array.

	if output == "json" {

pkg/cmd/taskrun/delete.go:237

• The --task deletion path records deleted TaskRun names in successfulRelatedDeletes, so this field becomes null even when TaskRuns were successfully deleted. Include both direct and related successes in the JSON result.

			Deleted: d.SuccessfulDeletes(),

[Copilot]

Pull request overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

Suppressed comments (1)

pkg/cmd/taskrun/delete.go:243

• In -o json mode this function currently returns after encoding JSON, so any accumulated deletion errors from d.Errors() are dropped (command can exit 0 even when deletes failed). Also, some early returns in the --task/--keep paths print human output and bypass JSON entirely, and when nothing is deleted the current slice construction can encode as null instead of []. Consider (1) emitting JSON for the early-return paths, (2) always encoding an empty array when nothing was deleted, and (3) returning d.Errors() after successfully writing JSON.

	if output == "json" {
		result := struct {
			Deleted []string `json:"deleted"`
		}{
			Deleted: append(append([]string(nil), d.SuccessfulRelatedDeletes()...), d.SuccessfulDeletes()...),

[Copilot]

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[Copilot]

Pull request overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

Suppressed comments (1)

pkg/cmd/taskrun/delete.go:246

• When neither accessor contains an item, these nested appends preserve a nil slice, so encoding/json emits {"deleted":null} rather than the {"deleted":[]} contract asserted by the new no-op test. Initialize the accumulation with a non-nil empty slice so no-op deletions still produce an array.

			Deleted: append(append([]string(nil), d.SuccessfulRelatedDeletes()...), d.SuccessfulDeletes()...),