Differential D20977 Diff 49988 src/infrastructure/lipsum/PhutilContextFreeGrammar.php

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src/infrastructure/lipsum/PhutilContextFreeGrammar.php

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				<?php

				/**
				* Generate nonsense test data according to a context-free grammar definition.
				*/
				abstract class PhutilContextFreeGrammar extends Phobject {

				private $limit = 65535;

				abstract protected function getRules();

				public function generateSeveral($count, $implode = ' ') {
				$paragraph = array();
				for ($ii = 0; $ii < $count; $ii++) {
				$paragraph[$ii] = $this->generate();
				}
				return implode($implode, $paragraph);
				}

				public function generate() {
				$count = 0;
				$rules = $this->getRules();
				return $this->applyRules('[start]', $count, $rules);
				}

				final protected function applyRules($input, &$count, array $rules) {
				if (++$count > $this->limit) {
				throw new Exception(pht('Token replacement count exceeded limit!'));
				}

				$matches = null;
				preg_match_all('/(\\[[^\\]]+\\])/', $input, $matches, PREG_OFFSET_CAPTURE);

				foreach (array_reverse($matches[1]) as $token_spec) {
				list($token, $offset) = $token_spec;
				$token_name = substr($token, 1, -1);
				$options = array();

				if (($name_end = strpos($token_name, ','))) {
				$options_parser = new PhutilSimpleOptions();
				$options = $options_parser->parse($token_name);
				$token_name = substr($token_name, 0, $name_end);
				}

				if (empty($rules[$token_name])) {
				throw new Exception(pht("Invalid token '%s' in grammar.", $token_name));
				}

				$key = array_rand($rules[$token_name]);
				$replacement = $this->applyRules($rules[$token_name][$key],
				$count, $rules);

				if (isset($options['indent'])) {
				if (is_numeric($options['indent'])) {
				$replacement = self::strPadLines($replacement, $options['indent']);
				} else {
				$replacement = self::strPadLines($replacement);
				}
				}
				if (isset($options['trim'])) {
				switch ($options['trim']) {
				case 'left':
				$replacement = ltrim($replacement);
				break;
				case 'right':
				$replacement = rtrim($replacement);
				break;
				default:
				case 'both':
				$replacement = trim($replacement);
				break;
				}
				}
				if (isset($options['block'])) {
				$replacement = "\n".$replacement."\n";
				}

				$input = substr_replace($input, $replacement, $offset, strlen($token));
				}

				return $input;
				}

				private static function strPadLines($text, $num_spaces = 2) {
				$text_lines = phutil_split_lines($text);
				foreach ($text_lines as $linenr => $line) {
				$text_lines[$linenr] = str_repeat(' ', $num_spaces).$line;
				}

				return implode('', $text_lines);
				}

				}