WP_CLI\Utils

launch_editor_for_input() │ WP-CLI 1.0

Launch system's $EDITOR for the user to edit some text.

No Hooks.

Returns

String|true|false. Edited text, if file is saved from editor; false, if no change to file.

Usage

launch_editor_for_input( $input, $title, $ext );
$input(string) (required)
Some form of text to edit (e.g. post content).
$title(string)
Title to display in the editor.
Default: 'WP-CLI'
$ext(string)
Extension to use with the temp file.
Default: 'tmp'

launch_editor_for_input() code WP-CLI 2.13.0-alpha

wp-cli/php/utils.php 
function launch_editor_for_input( $input, $title = 'WP-CLI', $ext = 'tmp' ) {

	check_proc_available( 'launch_editor_for_input' );

	$tmpdir = get_temp_dir();

	do {
		$tmpfile  = basename( $title );
		$tmpfile  = preg_replace( '|\.[^.]*$|', '', $tmpfile );
		$tmpfile .= '-' . substr( md5( (string) mt_rand() ), 0, 6 ); // phpcs:ignore WordPress.WP.AlternativeFunctions.rand_mt_rand -- no crypto and WP not loaded.
		$tmpfile  = $tmpdir . $tmpfile . '.' . $ext;
		$fp       = fopen( $tmpfile, 'xb' );
		if ( ! $fp && is_writable( $tmpdir ) && file_exists( $tmpfile ) ) {
			$tmpfile = '';
			continue;
		}
		if ( $fp ) {
			fclose( $fp );
		}
	} while ( ! $tmpfile );

	if ( ! $tmpfile ) {
		WP_CLI::error( 'Error creating temporary file.' );
	}

	file_put_contents( $tmpfile, $input );

	$editor = getenv( 'EDITOR' );
	if ( ! $editor ) {
		$editor = is_windows() ? 'notepad' : 'vi';
	}

	$descriptorspec = [ STDIN, STDOUT, STDERR ];
	$process        = proc_open_compat( "$editor " . escapeshellarg( $tmpfile ), $descriptorspec, $pipes );
	$r              = proc_close( $process );
	if ( $r ) {
		exit( $r );
	}

	$output = file_get_contents( $tmpfile );

	unlink( $tmpfile );

	if ( $output === $input ) {
		return false;
	}

	return $output;
}