Initial

system/Debug/Iterator.php

@@ -0,0 +1,130 @@
+<?php
+
+/**
+ * This file is part of CodeIgniter 4 framework.
+ *
+ * (c) CodeIgniter Foundation <admin@codeigniter.com>
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace CodeIgniter\Debug;
+
+use Closure;
+
+/**
+ * Iterator for debugging.
+ */
+class Iterator
+{
+    /**
+     * Stores the tests that we are to run.
+     *
+     * @var array
+     */
+    protected $tests = [];
+
+    /**
+     * Stores the results of each of the tests.
+     *
+     * @var array
+     */
+    protected $results = [];
+
+    /**
+     * Adds a test to run.
+     *
+     * Tests are simply closures that the user can define any sequence of
+     * things to happen during the test.
+     *
+     * @return $this
+     */
+    public function add(string $name, Closure $closure)
+    {
+        $name = strtolower($name);
+
+        $this->tests[$name] = $closure;
+
+        return $this;
+    }
+
+    /**
+     * Runs through all of the tests that have been added, recording
+     * time to execute the desired number of iterations, and the approximate
+     * memory usage used during those iterations.
+     *
+     * @return string|null
+     */
+    public function run(int $iterations = 1000, bool $output = true)
+    {
+        foreach ($this->tests as $name => $test) {
+            // clear memory before start
+            gc_collect_cycles();
+
+            $start    = microtime(true);
+            $startMem = $maxMemory = memory_get_usage(true);
+
+            for ($i = 0; $i < $iterations; $i++) {
+                $result    = $test();
+                $maxMemory = max($maxMemory, memory_get_usage(true));
+
+                unset($result);
+            }
+
+            $this->results[$name] = [
+                'time'   => microtime(true) - $start,
+                'memory' => $maxMemory - $startMem,
+                'n'      => $iterations,
+            ];
+        }
+
+        if ($output) {
+            return $this->getReport();
+        }
+
+        return null;
+    }
+
+    /**
+     * Get results.
+     */
+    public function getReport(): string
+    {
+        if (empty($this->results)) {
+            return 'No results to display.';
+        }
+
+        helper('number');
+
+        // Template
+        $tpl = '<table>
+			<thead>
+				<tr>
+					<td>Test</td>
+					<td>Time</td>
+					<td>Memory</td>
+				</tr>
+			</thead>
+			<tbody>
+				{rows}
+			</tbody>
+		</table>';
+
+        $rows = '';
+
+        foreach ($this->results as $name => $result) {
+            $memory = number_to_size($result['memory'], 4);
+
+            $rows .= "<tr>
+				<td>{$name}</td>
+				<td>" . number_format($result['time'], 4) . "</td>
+				<td>{$memory}</td>
+			</tr>";
+        }
+
+        $tpl = str_replace('{rows}', $rows, $tpl);
+
+        return $tpl . '<br/>';
+    }
+}