Add Cursor class to control the cursor in the terminal

src/Symfony/Component/Console/Cursor.php

@@ -0,0 +1,130 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Console;
+
+use Symfony\Component\Console\Output\OutputInterface;
+
+/**
+ * @author Pierre du Plessis <pdples@gmail.com>
+ */
+class Cursor
+{
+    private $output;
+
+    public function __construct(OutputInterface $output)
+    {
+        $this->output = $output;
+    }
+
+    public function moveUp(int $lines = 1)
+    {
+        $this->output->write(sprintf("\x1b[%dA", $lines));
+    }
+
+    public function moveDown(int $lines = 1)
+    {
+        $this->output->write(sprintf("\x1b[%dB", $lines));
+    }
+
+    public function moveRight(int $columns = 1)
+    {
+        $this->output->write(sprintf("\x1b[%dC", $columns));
+    }
+
+    public function moveLeft(int $columns = 1)
+    {
+        $this->output->write(sprintf("\x1b[%dD", $columns));
+    }
+
+    public function moveToColumn(int $column)
+    {
+        $this->output->write(sprintf("\x1b[%dG", $column));
+    }
+
+    public function moveToPosition(int $column, int $row)
+    {
+        $this->output->write(sprintf("\x1b[%d;%dH", $row + 1, $column));
+    }
+
+    public function savePosition()
+    {
+        $this->output->write("\x1b[s");
+    }
+
+    public function restorePosition()
+    {
+        $this->output->write("\x1b[u");
+    }
+
+    public function hide()
+    {
+        $this->output->write("\x1b[?25l");
+    }
+
+    public function show()
+    {
+        $this->output->write("\x1b[?25h\x1b[?0c");
+    }
+
+    /**
+     * Clears all the output from the of the current line.
+     */
+    public function clearLine()
+    {
+        $this->output->write("\x1b[2K");
+    }
+
+    /**
+     * Clears all the output from the cursors' current position to the end of the screen.
+     */
+    public function clearOutput()
+    {
+        $this->output->write("\x1b[0J", false);
+    }
+
+    /**
+     * Clears the entire screen.
+     */
+    public function clearScreen()
+    {
+        $this->output->write("\x1b[2J", false);
+    }
+
+    /**
+     * Returns the current cursor position as x,y coordinates.
+     */
+    public function getCurrentPosition(): array
+    {
+        static $isTtySupported;
+
+        if (null === $isTtySupported && function_exists('proc_open')) {
+            $isTtySupported = (bool) @proc_open('echo 1 >/dev/null', array(array('file', '/dev/tty', 'r'), array('file', '/dev/tty', 'w'), array('file', '/dev/tty', 'w')), $pipes);
+        }
+
+        if (!$isTtySupported) {
+            return array(1, 1);
+        }
+
+        $sttyMode = shell_exec('stty -g');
+        shell_exec('stty -icanon -echo');
+
+        fwrite(STDIN, "\033[6n");
+
+        $code = trim(fread(STDIN, 1024));
+
+        shell_exec(sprintf('stty %s', $sttyMode));
+
+        sscanf($code, "\033[%d;%dR", $row, $col);
+
+        return array($col, $row);
+    }
+}

src/Symfony/Component/Console/Tests/CursorTest.php

@@ -0,0 +1,208 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Console\Tests;
+
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\Console\Cursor;
+use Symfony\Component\Console\Output\StreamOutput;
+
+class CursorTest extends TestCase
+{
+    protected $stream;
+
+    protected function setUp()
+    {
+        $this->stream = fopen('php://memory', 'r+');
+    }
+
+    protected function tearDown()
+    {
+        fclose($this->stream);
+        $this->stream = null;
+    }
+
+    public function testMoveUpOneLine()
+    {
+        $cursor = new Cursor($output = $this->getOutputStream());
+
+        $cursor->moveUp();
+
+        $this->assertEquals("\x1b[1A", $this->getOutputContent($output));
+    }
+
+    public function testMoveUpMultipleLines()
+    {
+        $cursor = new Cursor($output = $this->getOutputStream());
+
+        $cursor->moveUp(12);
+
+        $this->assertEquals("\x1b[12A", $this->getOutputContent($output));
+    }
+
+    public function testMoveDownOneLine()
+    {
+        $cursor = new Cursor($output = $this->getOutputStream());
+
+        $cursor->moveDown();
+
+        $this->assertEquals("\x1b[1B", $this->getOutputContent($output));
+    }
+
+    public function testMoveDownMultipleLines()
+    {
+        $cursor = new Cursor($output = $this->getOutputStream());
+
+        $cursor->moveDown(12);
+
+        $this->assertEquals("\x1b[12B", $this->getOutputContent($output));
+    }
+
+    public function testMoveLeftOneLine()
+    {
+        $cursor = new Cursor($output = $this->getOutputStream());
+
+        $cursor->moveLeft();
+
+        $this->assertEquals("\x1b[1D", $this->getOutputContent($output));
+    }
+
+    public function testMoveLeftMultipleLines()
+    {
+        $cursor = new Cursor($output = $this->getOutputStream());
+
+        $cursor->moveLeft(12);
+
+        $this->assertEquals("\x1b[12D", $this->getOutputContent($output));
+    }
+
+    public function testMoveRightOneLine()
+    {
+        $cursor = new Cursor($output = $this->getOutputStream());
+
+        $cursor->moveRight();
+
+        $this->assertEquals("\x1b[1C", $this->getOutputContent($output));
+    }
+
+    public function testMoveRightMultipleLines()
+    {
+        $cursor = new Cursor($output = $this->getOutputStream());
+
+        $cursor->moveRight(12);
+
+        $this->assertEquals("\x1b[12C", $this->getOutputContent($output));
+    }
+
+    public function testMoveToColumn()
+    {
+        $cursor = new Cursor($output = $this->getOutputStream());
+
+        $cursor->moveToColumn(6);
+
+        $this->assertEquals("\x1b[6G", $this->getOutputContent($output));
+    }
+
+    public function testMoveToPosition()
+    {
+        $cursor = new Cursor($output = $this->getOutputStream());
+
+        $cursor->moveToPosition(18, 16);
+
+        $this->assertEquals("\x1b[17;18H", $this->getOutputContent($output));
+    }
+
+    public function testClearLine()
+    {
+        $cursor = new Cursor($output = $this->getOutputStream());
+
+        $cursor->clearLine();
+
+        $this->assertEquals("\x1b[2K", $this->getOutputContent($output));
+    }
+
+    public function testSavePosition()
+    {
+        $cursor = new Cursor($output = $this->getOutputStream());
+
+        $cursor->savePosition();
+
+        $this->assertEquals("\x1b[s", $this->getOutputContent($output));
+    }
+
+    public function testHide()
+    {
+        $cursor = new Cursor($output = $this->getOutputStream());
+
+        $cursor->hide();
+
+        $this->assertEquals("\x1b[?25l", $this->getOutputContent($output));
+    }
+
+    public function testShow()
+    {
+        $cursor = new Cursor($output = $this->getOutputStream());
+
+        $cursor->show();
+
+        $this->assertEquals("\x1b[?25h\x1b[?0c", $this->getOutputContent($output));
+    }
+
+    public function testRestorePosition()
+    {
+        $cursor = new Cursor($output = $this->getOutputStream());
+
+        $cursor->restorePosition();
+
+        $this->assertEquals("\x1b[u", $this->getOutputContent($output));
+    }
+
+    public function testClearOutput()
+    {
+        $cursor = new Cursor($output = $this->getOutputStream());
+
+        $cursor->clearOutput();
+
+        $this->assertEquals("\x1b[0J", $this->getOutputContent($output));
+    }
+
+    public function testGetCurrentPosition()
+    {
+        $cursor = new Cursor($output = $this->getOutputStream());
+
+        $cursor->moveToPosition(10, 10);
+        $position = $cursor->getCurrentPosition();
+
+        $this->assertEquals("\x1b[11;10H", $this->getOutputContent($output));
+
+        $isTtySupported = (bool) @proc_open('echo 1 >/dev/null', array(array('file', '/dev/tty', 'r'), array('file', '/dev/tty', 'w'), array('file', '/dev/tty', 'w')), $pipes);
+
+        if ($isTtySupported) {
+            // When tty is supported, we can't validate the exact cursor position since it depends where the cursor is when the test runs.
+            // Instead we just make sure that it doesn't return 1,1
+            $this->assertNotEquals(array(1, 1), $position);
+        } else {
+            $this->assertEquals(array(1, 1), $position);
+        }
+    }
+
+    protected function getOutputContent(StreamOutput $output)
+    {
+        rewind($output->getStream());
+
+        return str_replace(PHP_EOL, "\n", stream_get_contents($output->getStream()));
+    }
+
+    protected function getOutputStream(): StreamOutput
+    {
+        return new StreamOutput($this->stream, StreamOutput::VERBOSITY_NORMAL);
+    }
+}