Merge pull request #77 from PHPCSStandards/feature/add-support-for-arrow-functions

Add support for arrow functions

Author: jrfnl

PHPCSUtils/BackCompat/BCFile.php

@@ -38,7 +38,9 @@
 use PHP_CodeSniffer\Files\File;
 use PHP_CodeSniffer\Util\Tokens;
 use PHPCSUtils\BackCompat\BCTokens;
+use PHPCSUtils\BackCompat\Helper;
 use PHPCSUtils\Tokens\Collections;
+use PHPCSUtils\Utils\FunctionDeclarations;
 
 /**
  * PHPCS native utility functions.
@@ -94,6 +96,8 @@ class BCFile
  * - PHPCS 3.0.0: Added support for ES6 class/method syntax.
  * - PHPCS 3.0.0: The Exception thrown changed from a `PHP_CodeSniffer_Exception` to
  * `\PHP_CodeSniffer\Exceptions\RuntimeException`.
+ * - PHPCS 3.5.3: Allow for functions to be called `fn` for backwards compatibility.
+ * Related to PHP 7.4 T_FN arrow functions.
  *
  * Note: For ES6 classes in combination with PHPCS 2.x, passing a `T_STRING` token to
  * this method will be accepted for JS files.
@@ -103,6 +107,7 @@ class BCFile
  * @see \PHPCSUtils\Utils\ObjectDeclarations::getName() PHPCSUtils native improved version.
  *
  * @since 1.0.0
+ * @since 1.0.0-alpha2 Added BC support for PHP 7.4 arrow functions.
  *
  * @param \PHP_CodeSniffer\Files\File $phpcsFile The file being scanned.
  * @param int $stackPtr The position of the declaration token
@@ -153,7 +158,9 @@ public static function getDeclarationName(File $phpcsFile, $stackPtr)
 
  $content = null;
  for ($i = ($stackPtr + 1); $i < $phpcsFile->numTokens; $i++) {
- if ($tokens[$i]['code'] === T_STRING) {
+ if ($tokens[$i]['code'] === T_STRING
+ || $tokens[$i]['type'] === 'T_FN'
+ ) {
  /*
  * BC: In PHPCS 2.6.0, in case of live coding, the last token in a file will be tokenized
  * as T_STRING, but won't have the `content` index set.
@@ -238,11 +245,13 @@ public static function getDeclarationName(File $phpcsFile, $stackPtr)
  * be set in a "variadic_token" array index.
  * - PHPCS 3.5.3: Fixed a bug where the "type_hint_end_token" array index for a type hinted
  * parameter would bleed through to the next (non-type hinted) parameter.
+ * - PHPCS 3.5.3: Added support for PHP 7.4 T_FN arrow functions.
  *
  * @see \PHP_CodeSniffer\Files\File::getMethodParameters() Original source.
  * @see \PHPCSUtils\Utils\FunctionDeclarations::getParameters() PHPCSUtils native improved version.
  *
  * @since 1.0.0
+ * @since 1.0.0-alpha2 Added BC support for PHP 7.4 arrow functions.
  *
  * @param \PHP_CodeSniffer\Files\File $phpcsFile The file being scanned.
  * @param int $stackPtr The position in the stack of the function token
@@ -251,7 +260,8 @@ public static function getDeclarationName(File $phpcsFile, $stackPtr)
  * @return array
  *
  * @throws \PHP_CodeSniffer\Exceptions\RuntimeException If the specified $stackPtr is not of
- * type T_FUNCTION, T_CLOSURE, or T_USE.
+ * type T_FUNCTION, T_CLOSURE, T_USE,
+ * or T_FN.
  */
  public static function getMethodParameters(File $phpcsFile, $stackPtr)
  {
@@ -260,15 +270,25 @@ public static function getMethodParameters(File $phpcsFile, $stackPtr)
  if ($tokens[$stackPtr]['code'] !== T_FUNCTION
  && $tokens[$stackPtr]['code'] !== T_CLOSURE
  && $tokens[$stackPtr]['code'] !== T_USE
+ && FunctionDeclarations::isArrowFunction($phpcsFile, $stackPtr) === false
  ) {
- throw new RuntimeException('$stackPtr must be of type T_FUNCTION or T_CLOSURE or T_USE');
+ throw new RuntimeException('$stackPtr must be of type T_FUNCTION or T_CLOSURE or T_USE or T_FN');
  }
 
  if ($tokens[$stackPtr]['code'] === T_USE) {
  $opener = $phpcsFile->findNext(T_OPEN_PARENTHESIS, ($stackPtr + 1));
  if ($opener === false || isset($tokens[$opener]['parenthesis_owner']) === true) {
  throw new RuntimeException('$stackPtr was not a valid T_USE');
  }
+ } elseif ($tokens[$stackPtr]['code'] === \T_STRING || $tokens[$stackPtr]['type'] === 'T_FN') {
+ /*
+ * Arrow function in combination with PHP < 7.4 or PHPCS < 3.5.3.
+ */
+ $opener = $phpcsFile->findNext((Tokens::$emptyTokens + [\T_BITWISE_AND]), ($stackPtr + 1), null, true);
+ if ($opener === false || $tokens[$opener]['code'] !== T_OPEN_PARENTHESIS) {
+ // Live coding or syntax error, so no params to find.
+ return [];
+ }
  } else {
  if (isset($tokens[$stackPtr]['parenthesis_opener']) === false) {
  // Live coding or syntax error, so no params to find.
@@ -508,11 +528,13 @@ public static function getMethodParameters(File $phpcsFile, $stackPtr)
  * or `true` otherwise.
  * - PHPCS 3.5.0: The Exception thrown changed from a `TokenizerException` to
  * `\PHP_CodeSniffer\Exceptions\RuntimeException`.
+ * - PHPCS 3.5.3: Added support for PHP 7.4 T_FN arrow functions.
  *
  * @see \PHP_CodeSniffer\Files\File::getMethodProperties() Original source.
  * @see \PHPCSUtils\Utils\FunctionDeclarations::getProperties() PHPCSUtils native improved version.
  *
  * @since 1.0.0
+ * @since 1.0.0-alpha2 Added BC support for PHP 7.4 arrow functions.
  *
  * @param \PHP_CodeSniffer\Files\File $phpcsFile The file being scanned.
  * @param int $stackPtr The position in the stack of the function token to
@@ -521,16 +543,18 @@ public static function getMethodParameters(File $phpcsFile, $stackPtr)
  * @return array
  *
  * @throws \PHP_CodeSniffer\Exceptions\RuntimeException If the specified position is not a
- * T_FUNCTION or a T_CLOSURE token.
+ * T_FUNCTION, T_CLOSURE, or T_FN token.
  */
  public static function getMethodProperties(File $phpcsFile, $stackPtr)
  {
- $tokens = $phpcsFile->getTokens();
+ $tokens = $phpcsFile->getTokens();
+ $arrowOpenClose = FunctionDeclarations::getArrowFunctionOpenClose($phpcsFile, $stackPtr);
 
  if ($tokens[$stackPtr]['code'] !== T_FUNCTION
  && $tokens[$stackPtr]['code'] !== T_CLOSURE
+ && $arrowOpenClose === []
  ) {
- throw new RuntimeException('$stackPtr must be of type T_FUNCTION or T_CLOSURE');
+ throw new RuntimeException('$stackPtr must be of type T_FUNCTION or T_CLOSURE or T_FN');
  }
 
  if ($tokens[$stackPtr]['code'] === T_FUNCTION) {
@@ -595,13 +619,24 @@ public static function getMethodProperties(File $phpcsFile, $stackPtr)
  $nullableReturnType = false;
  $hasBody = true;
 
+ $parenthesisCloser = null;
  if (isset($tokens[$stackPtr]['parenthesis_closer']) === true) {
+ $parenthesisCloser = $tokens[$stackPtr]['parenthesis_closer'];
+ } elseif ($arrowOpenClose !== [] && $arrowOpenClose['parenthesis_closer'] !== false) {
+ // Arrow function in combination with PHP < 7.4 or PHPCS < 3.5.3.
+ $parenthesisCloser = $arrowOpenClose['parenthesis_closer'];
+ }
+
+ if (isset($parenthesisCloser) === true) {
  $scopeOpener = null;
  if (isset($tokens[$stackPtr]['scope_opener']) === true) {
  $scopeOpener = $tokens[$stackPtr]['scope_opener'];
+ } elseif ($arrowOpenClose !== [] && $arrowOpenClose['scope_opener'] !== false) {
+ // Arrow function in combination with PHP < 7.4 or PHPCS < 3.5.3.
+ $scopeOpener = $arrowOpenClose['scope_opener'];
  }
 
- for ($i = $tokens[$stackPtr]['parenthesis_closer']; $i < $phpcsFile->numTokens; $i++) {
+ for ($i = $parenthesisCloser; $i < $phpcsFile->numTokens; $i++) {
  if (($scopeOpener === null && $tokens[$i]['code'] === T_SEMICOLON)
  || ($scopeOpener !== null && $i === $scopeOpener)
  ) {
@@ -612,6 +647,9 @@ public static function getMethodProperties(File $phpcsFile, $stackPtr)
  if ($tokens[$i]['type'] === 'T_NULLABLE'
  // Handle nullable tokens in PHPCS < 2.8.0.
  || (defined('T_NULLABLE') === false && $tokens[$i]['code'] === T_INLINE_THEN)
+ // Handle nullable tokens with arrow functions in PHPCS 2.8.0 - 2.9.0.
+ || ($arrowOpenClose !== [] && $tokens[$i]['code'] === T_INLINE_THEN
+ && version_compare(Helper::getVersion(), '2.9.1', '<') === true)
  ) {
  $nullableReturnType = true;
  }
@@ -625,8 +663,17 @@ public static function getMethodProperties(File $phpcsFile, $stackPtr)
  }
  }
 
- $end = $phpcsFile->findNext([T_OPEN_CURLY_BRACKET, T_SEMICOLON], $tokens[$stackPtr]['parenthesis_closer']);
- $hasBody = $tokens[$end]['code'] === T_OPEN_CURLY_BRACKET;
+ $bodyTokens = [T_OPEN_CURLY_BRACKET => T_OPEN_CURLY_BRACKET];
+ if ($arrowOpenClose !== []) {
+ $bodyTokens = [T_DOUBLE_ARROW => T_DOUBLE_ARROW];
+ if (defined('T_FN_ARROW') === true) {
+ // PHPCS 3.5.3+.
+ $bodyTokens = [T_FN_ARROW => T_FN_ARROW];
+ }
+ }
+
+ $end = $phpcsFile->findNext(($bodyTokens + [T_SEMICOLON]), $parenthesisCloser);
+ $hasBody = isset($bodyTokens[$tokens[$end]['code']]);
  }
 
  if ($returnType !== '' && $nullableReturnType === true) {
@@ -923,11 +970,13 @@ public static function getClassProperties(File $phpcsFile, $stackPtr)
  * - New by reference was not recognized as a reference.
  * - References to class properties with `self::`, `parent::`, `static::`,
  * `namespace\ClassName::`, `classname::` were not recognized as references.
+ * - PHPCS 3.5.3: Added support for PHP 7.4 T_FN arrow functions returning by reference.
  *
  * @see \PHP_CodeSniffer\Files\File::isReference() Original source.
  * @see \PHPCSUtils\Utils\Operators::isReference() PHPCSUtils native improved version.
  *
  * @since 1.0.0
+ * @since 1.0.0-alpha2 Added BC support for PHP 7.4 arrow functions.
  *
  * @param \PHP_CodeSniffer\Files\File $phpcsFile The file being scanned.
  * @param int $stackPtr The position of the T_BITWISE_AND token.
@@ -945,7 +994,9 @@ public static function isReference(File $phpcsFile, $stackPtr)
 
  $tokenBefore = $phpcsFile->findPrevious(Tokens::$emptyTokens, ($stackPtr - 1), null, true);
 
- if ($tokens[$tokenBefore]['code'] === T_FUNCTION) {
+ if ($tokens[$tokenBefore]['code'] === T_FUNCTION
+ || FunctionDeclarations::isArrowFunction($phpcsFile, $tokenBefore) === true
+ ) {
  // Function returns a reference.
  return true;
  }
@@ -1116,10 +1167,12 @@ public static function getTokensAsString(File $phpcsFile, $start, $length, $orig
  * Changelog for the PHPCS native function:
  * - Introduced in PHPCS 2.1.0.
  * - PHPCS 2.6.2: New optional `$ignore` parameter to selectively ignore stop points.
+ * - PHPCS 3.5.5: Added support for PHP 7.4 T_FN arrow functions.
  *
  * @see \PHP_CodeSniffer\Files\File::findStartOfStatement() Original source.
  *
  * @since 1.0.0
+ * @since 1.0.0-alpha2 Added BC support for PHP 7.4 arrow functions.
  *
  * @param \PHP_CodeSniffer\Files\File $phpcsFile The file being scanned.
  * @param int $start The position to start searching from in the token stack.
@@ -1158,6 +1211,7 @@ public static function findStartOfStatement(File $phpcsFile, $start, $ignore = n
 
  if (isset($tokens[$i]['scope_opener']) === true
  && $i === $tokens[$i]['scope_closer']
+ && $tokens[$i]['code'] !== T_CLOSE_PARENTHESIS
  ) {
  // Found the end of the previous scope block.
  return $lastNotEmpty;
@@ -1193,10 +1247,13 @@ public static function findStartOfStatement(File $phpcsFile, $start, $ignore = n
  * - PHPCS 2.7.1: Improved handling of short arrays, PHPCS #1203.
  * - PHPCS 3.3.0: Bug fix: end of statement detection when passed a scope opener, PHPCS #1863.
  * - PHPCS 3.5.0: Improved handling of group use statements.
+ * - PHPCS 3.5.3: Added support for PHP 7.4 T_FN arrow functions.
+ * - PHPCS 3.5.4: Improved support for PHP 7.4 T_FN arrow functions.
  *
  * @see \PHP_CodeSniffer\Files\File::findEndOfStatement() Original source.
  *
  * @since 1.0.0
+ * @since 1.0.0-alpha2 Added BC support for PHP 7.4 arrow functions.
  *
  * @param \PHP_CodeSniffer\Files\File $phpcsFile The file being scanned.
  * @param int $start The position to start searching from in the token stack.
@@ -1251,6 +1308,12 @@ public static function findEndOfStatement(File $phpcsFile, $start, $ignore = nul
  && ($i === $tokens[$i]['scope_opener']
  || $i === $tokens[$i]['scope_condition'])
  ) {
+ if ($tokens[$i]['type'] === 'T_FN') {
+ // Minus 1 as the closer can be shared.
+ $i = ($tokens[$i]['scope_closer'] - 1);
+ continue;
+ }
+
  if ($i === $start && isset(Tokens::$scopeOpeners[$tokens[$i]['code']]) === true) {
  return $tokens[$i]['scope_closer'];
  }
@@ -1269,6 +1332,19 @@ public static function findEndOfStatement(File $phpcsFile, $start, $ignore = nul
  if ($end !== false) {
  $i = $end;
  }
+ } elseif ($tokens[$i]['code'] === T_STRING || $tokens[$i]['type'] === 'T_FN') {
+ // Potentially a PHP 7.4 arrow function in combination with PHP < 7.4 or PHPCS < 3.5.3/3.5.4.
+ $arrowFunctionOpenClose = FunctionDeclarations::getArrowFunctionOpenClose($phpcsFile, $i);
+ if ($arrowFunctionOpenClose !== []
+ && $arrowFunctionOpenClose['scope_closer'] !== false
+ ) {
+ if ($i === $start) {
+ return $arrowFunctionOpenClose['scope_closer'];
+ }
+
+ // Minus 1 as the closer can be shared.
+ $i = ($arrowFunctionOpenClose['scope_closer'] - 1);
+ }
  }
 
  if (isset(Tokens::$emptyTokens[$tokens[$i]['code']]) === false) {

PHPCSUtils/Tokens/Collections.php

@@ -308,7 +308,8 @@ class Collections
  \T_PARENT => \T_PARENT,
  \T_NS_SEPARATOR => \T_NS_SEPARATOR,
  \T_RETURN_TYPE => \T_RETURN_TYPE, // PHPCS 2.4.0 < 3.3.0.
- \T_ARRAY_HINT => \T_ARRAY_HINT, // PHPCS < 2.8.0.
+ \T_ARRAY_HINT => \T_ARRAY_HINT, // PHPCS < 2.8.0 / PHPCS < 3.5.3 for arrow functions.
+ \T_ARRAY => \T_ARRAY, // PHPCS < 3.5.4 for select arrow functions.
  ];
 
  /**

PHPCSUtils/Utils/Arrays.php

@@ -15,6 +15,7 @@
 use PHP_CodeSniffer\Util\Tokens;
 use PHPCSUtils\BackCompat\Helper;
 use PHPCSUtils\Tokens\Collections;
+use PHPCSUtils\Utils\FunctionDeclarations;
 use PHPCSUtils\Utils\Lists;
 
 /**
@@ -28,12 +29,16 @@ class Arrays
  /**
  * The tokens to target to find the double arrow in an array item.
  *
+ * Note: this array does not contain the `T_FN` token as it may or may not exist.
+ * If it exists, it will be added in the `getDoubleArrowPtr()` function.
+ *
  * @var array <int|string> => <int|string>
  */
  private static $doubleArrowTargets = [
  \T_DOUBLE_ARROW => \T_DOUBLE_ARROW,
  \T_ARRAY => \T_ARRAY,
  \T_OPEN_SHORT_ARRAY => \T_OPEN_SHORT_ARRAY,
+ \T_STRING => \T_STRING, // BC for T_FN token in PHPCS < 3.5.3 icw PHP < 7.4.
  ];
 
  /**
@@ -236,6 +241,9 @@ public static function getOpenClose(File $phpcsFile, $stackPtr, $isShortArray =
  * Expects to be passed the array item start and end tokens as retrieved via
  * {@see \PHPCSUtils\Utils\PassedParameters::getParameters()}.
  *
+ * @since 1.0.0
+ * @since 1.0.0-alpha2 Now allows for arrow functions in arrays.
+ *
  * @param \PHP_CodeSniffer\Files\File $phpcsFile The file being examined.
  * @param int $start Stack pointer to the start of the array item.
  * @param int $end Stack pointer to the end of the array item (inclusive).
@@ -256,6 +264,9 @@ public static function getDoubleArrowPtr(File $phpcsFile, $start, $end)
  }
 
  $targets = self::$doubleArrowTargets + Collections::$closedScopes;
+ if (\defined('T_FN') === true) {
+ $targets[\T_FN] = \T_FN;
+ }
 
  $doubleArrow = ($start - 1);
  ++$end;
@@ -282,7 +293,15 @@ public static function getDoubleArrowPtr(File $phpcsFile, $start, $end)
  continue;
  }
 
- // Start of nested long/short array.
+ // BC for PHP 7.4 arrow functions with PHPCS < 3.5.3.
+ if ($tokens[$doubleArrow]['code'] === \T_STRING
+ && FunctionDeclarations::isArrowFunction($phpcsFile, $doubleArrow) === false
+ ) {
+ // Not an arrow function, continue looking.
+ continue;
+ }
+
+ // Start of nested long/short array or arrow function.
  break;
  } while ($doubleArrow < $end);