Add wp term prune command to remove terms with 0 or 1 published posts

[Copilot]

• Add prune method to Term_Command class in src/Term_Command.php
• Update class-level docblock to include prune example
• Add "term prune" to the commands list in composer.json
• Create features/term-prune.feature with Behat tests
• Run linting and code style checks - all pass
• Run static analysis (PHPStan) - no errors
• Address code review feedback (removed unreachable else block, renamed variable)
• Combine the two separate foreach loops over $args into a single loop
• Remove unused $prunable variable

Original prompt

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This section details on the original issue you should resolve

<issue_title>Prune terms with one or less published posts</issue_title>
<issue_description>On large sites with thousands of tags or other terms, it would be helpful to have wp term prune to delete terms with one or less published posts.</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Prune terms with one or less published posts #585

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[gemini-code-assist]

Code Review

This pull request introduces a valuable wp term prune command for cleaning up unused or barely-used terms, which is particularly useful for large sites. The implementation is solid and is accompanied by a comprehensive set of Behat tests covering various scenarios. My review includes a single, significant suggestion to refactor the prune method. The proposed changes aim to improve performance by using a more efficient database query, enhance code readability by consolidating loops, and increase robustness by handling a potential edge case during term deletion. Overall, this is a great addition.

[gemini-code-assist]

The prune function can be refactored for better performance, readability, and robustness.

1. Performance: Instead of fetching all terms with get_terms() and then filtering them in PHP, it's more efficient to query the database directly for only the term IDs that need to be pruned (i.e., those with a count of 1 or less). This will significantly improve performance on sites with a large number of terms.
2. Readability: The two separate foreach loops iterating over $args can be combined into a single loop. You can perform the taxonomy_exists() check at the beginning of each iteration before proceeding with the pruning logic for that taxonomy.
3. Robustness: The wp_delete_term() function returns false if the term to be deleted doesn't exist. This edge case (which could happen in a race condition) should be handled by issuing a warning, similar to how the term delete command behaves.

Here is a suggested refactoring that applies these improvements:

        global $wpdb;

		$dry_run = (bool) Utils\get_flag_value( $assoc_args, 'dry-run', false );

		foreach ( $args as $taxonomy ) {
			if ( ! taxonomy_exists( $taxonomy ) ) {
				WP_CLI::error( "Taxonomy {$taxonomy} doesn't exist." );
			}

			$term_ids_to_prune = $wpdb->get_col(
				$wpdb->prepare(
					"SELECT term_id FROM {$wpdb->term_taxonomy} WHERE taxonomy = %s AND count <= 1",
					$taxonomy
				)
			);

			$total     = count( $term_ids_to_prune );
			$successes = 0;
			$errors    = 0;

			if ( $total > 0 ) {
				foreach ( $term_ids_to_prune as $term_id ) {
					if ( $dry_run ) {
						WP_CLI::log( "Would delete {$taxonomy} {$term_id}." );
						++$successes;
						continue;
					}

					$result = wp_delete_term( $term_id, $taxonomy );

					if ( is_wp_error( $result ) ) {
						WP_CLI::warning( $result );
						++$errors;
					} elseif ( $result ) {
						WP_CLI::log( "Deleted {$taxonomy} {$term_id}." );
						++$successes;
					} else {
						WP_CLI::warning( "Term {$term_id} in taxonomy {$taxonomy} doesn't exist." );
					}
				}
			}

			if ( $dry_run ) {
				$term_word = Utils\pluralize( 'term', $successes );
				WP_CLI::success( "{$successes} {$taxonomy} {$term_word} would be pruned." );
			} else {
				Utils\report_batch_operation_results( 'term', 'prune', $total, $successes, $errors );
			}
		}