Add a linter rule for modifier ordering

Summary: Fixes T7417. Adds `ArcanistXHPASTLinter::LINT_MODIFIER_ORDERING` for ensuring that method/property modifiers (`public`, `protected`, `private`, `static`, `abstract` and `final`) are consistently ordered. The modifier ordering that is enforced is consistent with [[http://www.php-fig.org/psr/psr-2 | PSR-2]].

Test Plan: Added unit tests.

Reviewers: epriestley, #blessed_reviewers

Reviewed By: epriestley, #blessed_reviewers

Subscribers: Korvin, epriestley

Maniphest Tasks: T7417

Differential Revision: https://secure.phabricator.com/D12421

src/lint/linter/ArcanistXHPASTLinter.php

@@ -70,6 +70,7 @@ final class ArcanistXHPASTLinter extends ArcanistBaseXHPASTLinter {
   const LINT_LAMBDA_FUNC_FUNCTION       = 68;
   const LINT_INSTANCEOF_OPERATOR        = 69;
   const LINT_INVALID_DEFAULT_PARAMETER  = 70;
+  const LINT_MODIFIER_ORDERING          = 71;
 
   private $blacklistedFunctions = array();
   private $naminghook;
@@ -218,6 +219,8 @@ final class ArcanistXHPASTLinter extends ArcanistBaseXHPASTLinter {
         => pht('%s Operator', 'instanceof'),
       self::LINT_INVALID_DEFAULT_PARAMETER
         => pht('Invalid Default Parameter'),
+      self::LINT_MODIFIER_ORDERING
+        => pht('Modifier Ordering'),
     );
   }
 
@@ -271,6 +274,7 @@ final class ArcanistXHPASTLinter extends ArcanistBaseXHPASTLinter {
       self::LINT_USELESS_OVERRIDING_METHOD  => $advice,
       self::LINT_ALIAS_FUNCTION             => $advice,
       self::LINT_CAST_SPACING               => $advice,
+      self::LINT_MODIFIER_ORDERING          => $advice,
     );
   }
 
@@ -338,7 +342,7 @@ final class ArcanistXHPASTLinter extends ArcanistBaseXHPASTLinter {
 
   public function getVersion() {
     // The version number should be incremented whenever a new rule is added.
-    return '32';
+    return '33';
   }
 
   protected function resolveFuture($path, Future $future) {
@@ -414,8 +418,8 @@ final class ArcanistXHPASTLinter extends ArcanistBaseXHPASTLinter {
       'lintConstructorParentheses' => self::LINT_CONSTRUCTOR_PARENTHESES,
       'lintSwitchStatements' => self::LINT_DUPLICATE_SWITCH_CASE,
       'lintBlacklistedFunction' => self::LINT_BLACKLISTED_FUNCTION,
-      'lintMethodModifier' => self::LINT_IMPLICIT_VISIBILITY,
-      'lintPropertyModifier' => self::LINT_IMPLICIT_VISIBILITY,
+      'lintMethodVisibility' => self::LINT_IMPLICIT_VISIBILITY,
+      'lintPropertyVisibility' => self::LINT_IMPLICIT_VISIBILITY,
       'lintCallTimePassByReference' => self::LINT_CALL_TIME_PASS_BY_REF,
       'lintFormattedString' => self::LINT_FORMATTED_STRING,
       'lintUnnecessaryFinalModifier' => self::LINT_UNNECESSARY_FINAL_MODIFIER,
@@ -435,6 +439,8 @@ final class ArcanistXHPASTLinter extends ArcanistBaseXHPASTLinter {
       'lintLambdaFuncFunction' => self::LINT_LAMBDA_FUNC_FUNCTION,
       'lintInstanceOfOperator' => self::LINT_INSTANCEOF_OPERATOR,
       'lintInvalidDefaultParameters' => self::LINT_INVALID_DEFAULT_PARAMETER,
+      'lintMethodModifierOrdering' => self::LINT_MODIFIER_ORDERING,
+      'lintPropertyModifierOrdering' => self::LINT_MODIFIER_ORDERING,
     );
 
     foreach ($method_codes as $method => $codes) {
@@ -3338,7 +3344,7 @@ final class ArcanistXHPASTLinter extends ArcanistBaseXHPASTLinter {
     }
   }
 
-  private function lintMethodModifier(XHPASTNode $root) {
+  private function lintMethodVisibility(XHPASTNode $root) {
     static $visibilities = array(
       'public',
       'protected',
@@ -3372,7 +3378,7 @@ final class ArcanistXHPASTLinter extends ArcanistBaseXHPASTLinter {
     }
   }
 
-  private function lintPropertyModifier(XHPASTNode $root) {
+  private function lintPropertyVisibility(XHPASTNode $root) {
     static $visibilities = array(
       'public',
       'protected',
@@ -4308,4 +4314,62 @@ final class ArcanistXHPASTLinter extends ArcanistBaseXHPASTLinter {
     }
   }
 
+  private function lintMethodModifierOrdering(XHPASTNode $root) {
+    static $modifiers = array(
+      'abstract',
+      'final',
+      'public',
+      'protected',
+      'private',
+      'static',
+    );
+
+    $methods = $root->selectDescendantsOfType('n_METHOD_MODIFIER_LIST');
+
+    foreach ($methods as $method) {
+      $modifier_ordering = array_values(
+        mpull($method->getChildren(), 'getConcreteString'));
+      $expected_modifier_ordering = array_values(
+        array_intersect(
+          $modifiers,
+          $modifier_ordering));
+
+      if ($modifier_ordering != $expected_modifier_ordering) {
+        $this->raiseLintAtNode(
+          $method,
+          self::LINT_MODIFIER_ORDERING,
+          pht('Non-conventional modifier ordering.'),
+          implode(' ', $expected_modifier_ordering));
+      }
+    }
+  }
+
+  private function lintPropertyModifierOrdering(XHPASTNode $root) {
+    static $modifiers = array(
+      'public',
+      'protected',
+      'private',
+      'static',
+    );
+
+    $properties = $root->selectDescendantsOfType(
+      'n_CLASS_MEMBER_MODIFIER_LIST');
+
+    foreach ($properties as $property) {
+      $modifier_ordering = array_values(
+        mpull($property->getChildren(), 'getConcreteString'));
+      $expected_modifier_ordering = array_values(
+        array_intersect(
+          $modifiers,
+          $modifier_ordering));
+
+      if ($modifier_ordering != $expected_modifier_ordering) {
+        $this->raiseLintAtNode(
+          $property,
+          self::LINT_MODIFIER_ORDERING,
+          pht('Non-conventional modifier ordering.'),
+          implode(' ', $expected_modifier_ordering));
+      }
+    }
+  }
 }

src/lint/linter/__tests__/xhpast/modifier-ordering.lint-test

@@ -0,0 +1,24 @@
+<?php
+class Foo {
+  public $x;
+  static protected $y;
+
+  public final function bar() {}
+  private function baz() {}
+  static final public function foobar() {}
+}
+~~~~~~~~~~
+error:2:7 XHP19
+advice:4:3
+advice:6:3
+advice:8:3
+~~~~~~~~~~
+<?php
+class Foo {
+  public $x;
+  protected static $y;
+
+  final public function bar() {}
+  private function baz() {}
+  final public static function foobar() {}
+}

src/lint/linter/__tests__/xhpast/unnecessary-final-modifier.lint-test

@@ -1,8 +1,8 @@
 <?php
 final class Foo {
   public function bar() {}
-  public final function baz() {}
+  final public function baz() {}
 }
 ~~~~~~~~~~
 error:2:13 XHP19
-advice:4:10
+advice:4:3