diff options
Diffstat (limited to 'vendor/nikic/php-parser/lib/PhpParser/Lexer/Emulative.php')
| -rw-r--r-- | vendor/nikic/php-parser/lib/PhpParser/Lexer/Emulative.php | 248 |
1 files changed, 248 insertions, 0 deletions
diff --git a/vendor/nikic/php-parser/lib/PhpParser/Lexer/Emulative.php b/vendor/nikic/php-parser/lib/PhpParser/Lexer/Emulative.php new file mode 100644 index 000000000..5c56e026b --- /dev/null +++ b/vendor/nikic/php-parser/lib/PhpParser/Lexer/Emulative.php @@ -0,0 +1,248 @@ +<?php declare(strict_types=1); + +namespace PhpParser\Lexer; + +use PhpParser\Error; +use PhpParser\ErrorHandler; +use PhpParser\Lexer; +use PhpParser\Lexer\TokenEmulator\AttributeEmulator; +use PhpParser\Lexer\TokenEmulator\EnumTokenEmulator; +use PhpParser\Lexer\TokenEmulator\CoaleseEqualTokenEmulator; +use PhpParser\Lexer\TokenEmulator\ExplicitOctalEmulator; +use PhpParser\Lexer\TokenEmulator\FlexibleDocStringEmulator; +use PhpParser\Lexer\TokenEmulator\FnTokenEmulator; +use PhpParser\Lexer\TokenEmulator\MatchTokenEmulator; +use PhpParser\Lexer\TokenEmulator\NullsafeTokenEmulator; +use PhpParser\Lexer\TokenEmulator\NumericLiteralSeparatorEmulator; +use PhpParser\Lexer\TokenEmulator\ReadonlyTokenEmulator; +use PhpParser\Lexer\TokenEmulator\ReverseEmulator; +use PhpParser\Lexer\TokenEmulator\TokenEmulator; + +class Emulative extends Lexer +{ + const PHP_7_3 = '7.3dev'; + const PHP_7_4 = '7.4dev'; + const PHP_8_0 = '8.0dev'; + const PHP_8_1 = '8.1dev'; + + /** @var mixed[] Patches used to reverse changes introduced in the code */ + private $patches = []; + + /** @var TokenEmulator[] */ + private $emulators = []; + + /** @var string */ + private $targetPhpVersion; + + /** + * @param mixed[] $options Lexer options. In addition to the usual options, + * accepts a 'phpVersion' string that specifies the + * version to emulate. Defaults to newest supported. + */ + public function __construct(array $options = []) + { + $this->targetPhpVersion = $options['phpVersion'] ?? Emulative::PHP_8_1; + unset($options['phpVersion']); + + parent::__construct($options); + + $emulators = [ + new FlexibleDocStringEmulator(), + new FnTokenEmulator(), + new MatchTokenEmulator(), + new CoaleseEqualTokenEmulator(), + new NumericLiteralSeparatorEmulator(), + new NullsafeTokenEmulator(), + new AttributeEmulator(), + new EnumTokenEmulator(), + new ReadonlyTokenEmulator(), + new ExplicitOctalEmulator(), + ]; + + // Collect emulators that are relevant for the PHP version we're running + // and the PHP version we're targeting for emulation. + foreach ($emulators as $emulator) { + $emulatorPhpVersion = $emulator->getPhpVersion(); + if ($this->isForwardEmulationNeeded($emulatorPhpVersion)) { + $this->emulators[] = $emulator; + } else if ($this->isReverseEmulationNeeded($emulatorPhpVersion)) { + $this->emulators[] = new ReverseEmulator($emulator); + } + } + } + + public function startLexing(string $code, ErrorHandler $errorHandler = null) { + $emulators = array_filter($this->emulators, function($emulator) use($code) { + return $emulator->isEmulationNeeded($code); + }); + + if (empty($emulators)) { + // Nothing to emulate, yay + parent::startLexing($code, $errorHandler); + return; + } + + $this->patches = []; + foreach ($emulators as $emulator) { + $code = $emulator->preprocessCode($code, $this->patches); + } + + $collector = new ErrorHandler\Collecting(); + parent::startLexing($code, $collector); + $this->sortPatches(); + $this->fixupTokens(); + + $errors = $collector->getErrors(); + if (!empty($errors)) { + $this->fixupErrors($errors); + foreach ($errors as $error) { + $errorHandler->handleError($error); + } + } + + foreach ($emulators as $emulator) { + $this->tokens = $emulator->emulate($code, $this->tokens); + } + } + + private function isForwardEmulationNeeded(string $emulatorPhpVersion): bool { + return version_compare(\PHP_VERSION, $emulatorPhpVersion, '<') + && version_compare($this->targetPhpVersion, $emulatorPhpVersion, '>='); + } + + private function isReverseEmulationNeeded(string $emulatorPhpVersion): bool { + return version_compare(\PHP_VERSION, $emulatorPhpVersion, '>=') + && version_compare($this->targetPhpVersion, $emulatorPhpVersion, '<'); + } + + private function sortPatches() + { + // Patches may be contributed by different emulators. + // Make sure they are sorted by increasing patch position. + usort($this->patches, function($p1, $p2) { + return $p1[0] <=> $p2[0]; + }); + } + + private function fixupTokens() + { + if (\count($this->patches) === 0) { + return; + } + + // Load first patch + $patchIdx = 0; + + list($patchPos, $patchType, $patchText) = $this->patches[$patchIdx]; + + // We use a manual loop over the tokens, because we modify the array on the fly + $pos = 0; + for ($i = 0, $c = \count($this->tokens); $i < $c; $i++) { + $token = $this->tokens[$i]; + if (\is_string($token)) { + if ($patchPos === $pos) { + // Only support replacement for string tokens. + assert($patchType === 'replace'); + $this->tokens[$i] = $patchText; + + // Fetch the next patch + $patchIdx++; + if ($patchIdx >= \count($this->patches)) { + // No more patches, we're done + return; + } + list($patchPos, $patchType, $patchText) = $this->patches[$patchIdx]; + } + + $pos += \strlen($token); + continue; + } + + $len = \strlen($token[1]); + $posDelta = 0; + while ($patchPos >= $pos && $patchPos < $pos + $len) { + $patchTextLen = \strlen($patchText); + if ($patchType === 'remove') { + if ($patchPos === $pos && $patchTextLen === $len) { + // Remove token entirely + array_splice($this->tokens, $i, 1, []); + $i--; + $c--; + } else { + // Remove from token string + $this->tokens[$i][1] = substr_replace( + $token[1], '', $patchPos - $pos + $posDelta, $patchTextLen + ); + $posDelta -= $patchTextLen; + } + } elseif ($patchType === 'add') { + // Insert into the token string + $this->tokens[$i][1] = substr_replace( + $token[1], $patchText, $patchPos - $pos + $posDelta, 0 + ); + $posDelta += $patchTextLen; + } else if ($patchType === 'replace') { + // Replace inside the token string + $this->tokens[$i][1] = substr_replace( + $token[1], $patchText, $patchPos - $pos + $posDelta, $patchTextLen + ); + } else { + assert(false); + } + + // Fetch the next patch + $patchIdx++; + if ($patchIdx >= \count($this->patches)) { + // No more patches, we're done + return; + } + + list($patchPos, $patchType, $patchText) = $this->patches[$patchIdx]; + + // Multiple patches may apply to the same token. Reload the current one to check + // If the new patch applies + $token = $this->tokens[$i]; + } + + $pos += $len; + } + + // A patch did not apply + assert(false); + } + + /** + * Fixup line and position information in errors. + * + * @param Error[] $errors + */ + private function fixupErrors(array $errors) { + foreach ($errors as $error) { + $attrs = $error->getAttributes(); + + $posDelta = 0; + $lineDelta = 0; + foreach ($this->patches as $patch) { + list($patchPos, $patchType, $patchText) = $patch; + if ($patchPos >= $attrs['startFilePos']) { + // No longer relevant + break; + } + + if ($patchType === 'add') { + $posDelta += strlen($patchText); + $lineDelta += substr_count($patchText, "\n"); + } else if ($patchType === 'remove') { + $posDelta -= strlen($patchText); + $lineDelta -= substr_count($patchText, "\n"); + } + } + + $attrs['startFilePos'] += $posDelta; + $attrs['endFilePos'] += $posDelta; + $attrs['startLine'] += $lineDelta; + $attrs['endLine'] += $lineDelta; + $error->setAttributes($attrs); + } + } +} |