fix: pass prompt text to readline in CLI::prompt() so backspace does not erase it

Author: paulbalandan

system/CLI/CLI.php

@@ -254,12 +254,12 @@ public static function prompt(string $field, $options = null, $validation = null
             $default = $options[0];
         }
 
-        static::fwrite(STDOUT, $field . (trim($field) !== '' ? ' ' : '') . $extraOutput . ': ');
         static::$lastWrite = 'write';
 
-        // Read the input from keyboard.
-        $input = trim(static::$io->input());
-        $input = ($input === '') ? (string) $default : $input;
+        // The reader renders the prompt itself, so readline redraws repaint it instead of erasing it.
+        $prompt = sprintf('%s%s%s: ', $field, trim($field) !== '' ? ' ' : '', $extraOutput);
+        $input  = trim(static::$io->input($prompt));
+        $input  = $input === '' ? (string) $default : $input;
 
         if ($validation !== []) {
             while (! static::validate('"' . trim($field) . '"', $input, $validation)) {

system/CLI/InputOutput.php

@@ -43,10 +43,18 @@ public function input(?string $prefix = null): string
     {
         // readline() can't be tested.
         if ($this->readlineSupport && ENVIRONMENT !== 'testing') {
-            return readline($prefix); // @codeCoverageIgnore
+            // @codeCoverageIgnoreStart
+            // Libedit reports "EditLine wrapper" and mangles the markers, so only GNU readline gets them.
+            if ($prefix !== null && ! str_contains(readline_info('library_version'), 'EditLine')) {
+                $prefix = $this->markAnsiNonPrinting($prefix);
+            }
+
+            return readline($prefix);
+            // @codeCoverageIgnoreEnd
         }
 
-        echo $prefix;
+        // self:: skips MockInputOutput's fwrite override, whose filter bookkeeping must not nest inside input().
+        self::fwrite(STDOUT, $prefix ?? '');
 
         $input = fgets(fopen('php://stdin', 'rb'));
 
@@ -77,4 +85,12 @@ public function fwrite($handle, string $string): void
 
         fwrite($handle, $string);
     }
+
+    /**
+     * Wraps ANSI escape sequences in readline's non-printing markers so line-redraw column accounting skips them.
+     */
+    private function markAnsiNonPrinting(string $prefix): string
+    {
+        return preg_replace('/(\e\[[0-9;]*m)/', "\x01\$1\x02", $prefix);
+    }
 }

tests/system/CLI/CLITest.php

@@ -17,6 +17,7 @@
 use CodeIgniter\Exceptions\RuntimeException;
 use CodeIgniter\Superglobals;
 use CodeIgniter\Test\CIUnitTestCase;
+use CodeIgniter\Test\Mock\MockInputOutput;
 use CodeIgniter\Test\PhpStreamWrapper;
 use CodeIgniter\Test\StreamFilterTrait;
 use PHPUnit\Framework\Attributes\DataProvider;
@@ -143,6 +144,129 @@ public function testPromptInputZero(): void
         $this->assertSame('0', $output);
     }
 
+    public function testPromptPassesPromptTextToInputReader(): void
+    {
+        $io = new class () extends InputOutput {
+            public ?string $receivedPrefix = null;
+
+            public function input(?string $prefix = null): string
+            {
+                $this->receivedPrefix = $prefix;
+
+                return 'red';
+            }
+        };
+        CLI::setInputOutput($io);
+
+        $output = CLI::prompt('What is your favorite color?');
+
+        CLI::resetInputOutput();
+
+        $this->assertSame('red', $output);
+        $this->assertSame('What is your favorite color? : ', $io->receivedPrefix);
+    }
+
+    public function testPromptPassesDefaultOptionInPromptText(): void
+    {
+        $io = new class () extends InputOutput {
+            public ?string $receivedPrefix = null;
+
+            public function input(?string $prefix = null): string
+            {
+                $this->receivedPrefix = $prefix;
+
+                return '';
+            }
+        };
+        CLI::setInputOutput($io);
+
+        $output = CLI::prompt('What is your favorite color?', 'red');
+
+        CLI::resetInputOutput();
+
+        $this->assertSame('red', $output);
+        $this->assertSame(
+            sprintf('What is your favorite color?  [%s]: ', CLI::color('red', 'green')),
+            $io->receivedPrefix,
+        );
+    }
+
+    public function testPromptByKeyPassesPromptTextToInputReader(): void
+    {
+        $io = new class () extends InputOutput {
+            public ?string $receivedPrefix = null;
+
+            public function input(?string $prefix = null): string
+            {
+                $this->receivedPrefix = $prefix;
+
+                return '1';
+            }
+        };
+        CLI::setInputOutput($io);
+
+        $output = CLI::promptByKey('Select your hobbies:', ['Playing game', 'Sleep', 'Badminton']);
+
+        CLI::resetInputOutput();
+
+        $this->assertSame('1', $output);
+        $this->assertSame(
+            PHP_EOL . sprintf('[%s, 1, 2]: ', CLI::color('0', 'green')),
+            $io->receivedPrefix,
+        );
+    }
+
+    public function testPromptByMultipleKeysPassesPromptTextToInputReader(): void
+    {
+        $io = new class () extends InputOutput {
+            public ?string $receivedPrefix = null;
+
+            public function input(?string $prefix = null): string
+            {
+                $this->receivedPrefix = $prefix;
+
+                return '0,1';
+            }
+        };
+        CLI::setInputOutput($io);
+
+        $output = CLI::promptByMultipleKeys('Select your hobbies:', ['Playing game', 'Sleep', 'Badminton']);
+
+        CLI::resetInputOutput();
+
+        $this->assertSame([0 => 'Playing game', 1 => 'Sleep'], $output);
+        $this->assertSame(
+            'You can specify multiple values separated by commas.' . PHP_EOL
+                . sprintf('[%s, 1, 2] : ', CLI::color('0', 'green')),
+            $io->receivedPrefix,
+        );
+    }
+
+    public function testInputWritesPrefixToStdout(): void
+    {
+        $io = new MockInputOutput();
+        $io->setInputs(['blue']);
+        CLI::setInputOutput($io);
+
+        $output = CLI::input('Name: ');
+
+        CLI::resetInputOutput();
+
+        $this->assertSame('blue', $output);
+        $this->assertSame('Name: blue' . PHP_EOL, $io->getOutput());
+    }
+
+    public function testMarkAnsiNonPrintingWrapsEscapeSequences(): void
+    {
+        $wrap = $this->getPrivateMethodInvoker(new InputOutput(), 'markAnsiNonPrinting');
+
+        $this->assertSame(
+            "What is your favorite color?  [\x01\e[0;32m\x02red\x01\e[0m\x02]: ",
+            $wrap(sprintf('What is your favorite color?  [%s]: ', CLI::color('red', 'green'))),
+        );
+        $this->assertSame('Name: ', $wrap('Name: '));
+    }
+
     public function testPromptByKey(): void
     {
         PhpStreamWrapper::register();

user_guide_src/source/changelogs/v4.7.5.rst

@@ -34,6 +34,8 @@ Deprecations
 Bugs Fixed
 **********
 
+- **CLI:** Fixed a bug where pressing backspace in a ``CLI::prompt()`` erased the prompt text when the ``readline`` extension is enabled. The prompt is now passed to ``readline()`` so line redraws repaint it.
+  ANSI color codes in the prompt (e.g., option defaults) are wrapped in readline's non-printing markers under GNU readline so cursor positioning stays accurate.
 - **CLIRequest:** Fixed a bug where ``parseCommand()`` could throw a TypeError when ``argv`` is missing.
 - **Content Security Policy:** Fixed a bug where empty ``Content-Security-Policy``, ``Content-Security-Policy-Report-Only``, and ``Reporting-Endpoints`` response headers were generated when no corresponding values existed.
 - **Helpers:** Fixed a bug where ``get_dir_file_info()`` returned incomplete entries for subdirectories and missing files instead of omitting them.