(stable) Promote 2021 Week 6

src/__phutil_library_map__.php

@@ -402,6 +402,8 @@ phutil_register_library_map(array(
     'ArcanistParenthesesSpacingXHPASTLinterRuleTestCase' => 'lint/linter/xhpast/rules/__tests__/ArcanistParenthesesSpacingXHPASTLinterRuleTestCase.php',
     'ArcanistParseStrUseXHPASTLinterRule' => 'lint/linter/xhpast/rules/ArcanistParseStrUseXHPASTLinterRule.php',
     'ArcanistParseStrUseXHPASTLinterRuleTestCase' => 'lint/linter/xhpast/rules/__tests__/ArcanistParseStrUseXHPASTLinterRuleTestCase.php',
+    'ArcanistPartialCatchXHPASTLinterRule' => 'lint/linter/xhpast/rules/ArcanistPartialCatchXHPASTLinterRule.php',
+    'ArcanistPartialCatchXHPASTLinterRuleTestCase' => 'lint/linter/xhpast/rules/__tests__/ArcanistPartialCatchXHPASTLinterRuleTestCase.php',
     'ArcanistPasteRef' => 'ref/paste/ArcanistPasteRef.php',
     'ArcanistPasteSymbolRef' => 'ref/paste/ArcanistPasteSymbolRef.php',
     'ArcanistPasteWorkflow' => 'workflow/ArcanistPasteWorkflow.php',
@@ -1451,6 +1453,8 @@ phutil_register_library_map(array(
     'ArcanistParenthesesSpacingXHPASTLinterRuleTestCase' => 'ArcanistXHPASTLinterRuleTestCase',
     'ArcanistParseStrUseXHPASTLinterRule' => 'ArcanistXHPASTLinterRule',
     'ArcanistParseStrUseXHPASTLinterRuleTestCase' => 'ArcanistXHPASTLinterRuleTestCase',
+    'ArcanistPartialCatchXHPASTLinterRule' => 'ArcanistXHPASTLinterRule',
+    'ArcanistPartialCatchXHPASTLinterRuleTestCase' => 'ArcanistXHPASTLinterRuleTestCase',
     'ArcanistPasteRef' => 'ArcanistRef',
     'ArcanistPasteSymbolRef' => 'ArcanistSimpleSymbolRef',
     'ArcanistPasteWorkflow' => 'ArcanistArcWorkflow',

src/lint/linter/ArcanistPhutilLibraryLinter.php

@@ -13,6 +13,7 @@ final class ArcanistPhutilLibraryLinter extends ArcanistLinter {
   const LINT_UNKNOWN_SYMBOL      = 1;
   const LINT_DUPLICATE_SYMBOL    = 2;
   const LINT_ONE_CLASS_PER_FILE  = 3;
+  const LINT_NONCANONICAL_SYMBOL = 4;
 
   public function getInfoName() {
     return pht('Phutil Library Linter');
@@ -43,6 +44,7 @@ final class ArcanistPhutilLibraryLinter extends ArcanistLinter {
       self::LINT_UNKNOWN_SYMBOL      => pht('Unknown Symbol'),
       self::LINT_DUPLICATE_SYMBOL    => pht('Duplicate Symbol'),
       self::LINT_ONE_CLASS_PER_FILE  => pht('One Class Per File'),
+      self::LINT_NONCANONICAL_SYMBOL => pht('Noncanonical Symbol'),
     );
   }
 
@@ -51,6 +53,14 @@ final class ArcanistPhutilLibraryLinter extends ArcanistLinter {
   }
 
   public function willLintPaths(array $paths) {
+
+    $libtype_map = array(
+      'class' => 'class',
+      'function' => 'function',
+      'interface' => 'class',
+      'class/interface' => 'class',
+    );
+
     // NOTE: For now, we completely ignore paths and just lint every library in
     // its entirety. This is simpler and relatively fast because we don't do any
     // detailed checks and all the data we need for this comes out of module
@@ -59,6 +69,26 @@ final class ArcanistPhutilLibraryLinter extends ArcanistLinter {
     $bootloader = PhutilBootloader::getInstance();
     $libraries  = $bootloader->getAllLibraries();
 
+    // Load all the builtin symbols first.
+    $builtin_map = PhutilLibraryMapBuilder::newBuiltinMap();
+    $builtin_map = $builtin_map['have'];
+
+    $normal_symbols = array();
+    $all_symbols = array();
+    foreach ($builtin_map as $type => $builtin_symbols) {
+      $libtype = $libtype_map[$type];
+      foreach ($builtin_symbols as $builtin_symbol => $ignored) {
+        $normal_symbol = $this->normalizeSymbol($builtin_symbol);
+        $normal_symbols[$type][$normal_symbol] = $builtin_symbol;
+
+        $all_symbols[$libtype][$builtin_symbol] = array(
+          'library' => null,
+          'file' => null,
+          'offset' => null,
+        );
+      }
+    }
+
     // Load the up-to-date map for each library, without loading the library
     // itself. This means lint results will accurately reflect the state of
     // the working copy.
@@ -78,7 +108,6 @@ final class ArcanistPhutilLibraryLinter extends ArcanistLinter {
       }
     }
 
-    $all_symbols = array();
     foreach ($symbols as $library => $map) {
       // Check for files which declare more than one class/interface in the same
       // file, or mix function definitions with class/interface definitions. We
@@ -124,13 +153,20 @@ final class ArcanistPhutilLibraryLinter extends ArcanistLinter {
       }
 
       // Check for duplicate symbols: two files providing the same class or
-      // function.
+      // function. While doing this, we also build a map of normalized symbol
+      // names to original symbol names: we want a definition of "idx()" to
+      // collide with a definition of "IdX()", and want to perform spelling
+      // corrections later.
+
       foreach ($map as $file => $spec) {
         $have = idx($spec, 'have', array());
         foreach (array('class', 'function', 'interface') as $type) {
-          $libtype = ($type == 'interface') ? 'class' : $type;
+          $libtype = $libtype_map[$type];
           foreach (idx($have, $type, array()) as $symbol => $offset) {
-            if (empty($all_symbols[$libtype][$symbol])) {
+            $normal_symbol = $this->normalizeSymbol($symbol);
+
+            if (empty($normal_symbols[$libtype][$normal_symbol])) {
+              $normal_symbols[$libtype][$normal_symbol] = $symbol;
               $all_symbols[$libtype][$symbol] = array(
                 'library' => $library,
                 'file'    => $file,
@@ -139,23 +175,41 @@ final class ArcanistPhutilLibraryLinter extends ArcanistLinter {
               continue;
             }
 
-            $osrc = $all_symbols[$libtype][$symbol]['file'];
+            $old_symbol = $normal_symbols[$libtype][$normal_symbol];
-            $olib = $all_symbols[$libtype][$symbol]['library'];
+            $old_src = $all_symbols[$libtype][$old_symbol]['file'];
+            $old_lib = $all_symbols[$libtype][$old_symbol]['library'];
+
+            // If these values are "null", it means that the symbol is a
+            // builtin symbol provided by PHP or a PHP extension.
+
+            if ($old_lib === null) {
+              $message = pht(
+                'Definition of symbol "%s" (of type "%s") in file "%s" in '.
+                'library "%s" duplicates builtin definition of the same '.
+                'symbol.',
+                $symbol,
+                $type,
+                $file,
+                $library);
+            } else {
+              $message = pht(
+                'Definition of symbol "%s" (of type "%s") in file "%s" in '.
+                'library "%s" duplicates prior definition in file "%s" in '.
+                'library "%s".',
+                $symbol,
+                $type,
+                $file,
+                $library,
+                $old_src,
+                $old_lib);
+            }
 
             $this->raiseLintInLibrary(
               $library,
               $file,
               $offset,
               self::LINT_DUPLICATE_SYMBOL,
-              pht(
+              $message);
-                "Definition of %s '%s' in '%s' in library '%s' duplicates ".
-                "prior definition in '%s' in library '%s'.",
-                $type,
-                $symbol,
-                $file,
-                $library,
-                $osrc,
-                $olib));
           }
         }
       }
@@ -169,61 +223,148 @@ final class ArcanistPhutilLibraryLinter extends ArcanistLinter {
       foreach ($map as $file => $spec) {
         $need = idx($spec, 'need', array());
         foreach ($types as $type) {
-          $libtype = $type;
+          $libtype = $libtype_map[$type];
-          if ($type == 'interface' || $type == 'class/interface') {
-            $libtype = 'class';
-          }
           foreach (idx($need, $type, array()) as $symbol => $offset) {
             if (!empty($all_symbols[$libtype][$symbol])) {
               // Symbol is defined somewhere.
               continue;
             }
 
-            $libphutil_root = dirname(phutil_get_library_root('arcanist'));
+            $normal_symbol = $this->normalizeSymbol($symbol);
+            if (!empty($normal_symbols[$libtype][$normal_symbol])) {
+              $proper_symbol = $normal_symbols[$libtype][$normal_symbol];
+
+              switch ($type) {
+                case 'class':
+                  $summary = pht(
+                    'Class symbol "%s" should be written as "%s".',
+                    $symbol,
+                    $proper_symbol);
+                  break;
+                case 'function':
+                  $summary = pht(
+                    'Function symbol "%s" should be written as "%s".',
+                    $symbol,
+                    $proper_symbol);
+                  break;
+                case 'interface':
+                  $summary = pht(
+                    'Interface symbol "%s" should be written as "%s".',
+                    $symbol,
+                    $proper_symbol);
+                  break;
+                case 'class/interface':
+                  $summary = pht(
+                    'Class or interface symbol "%s" should be written as "%s".',
+                    $symbol,
+                    $proper_symbol);
+                  break;
+                default:
+                  throw new Exception(
+                    pht('Unknown symbol type "%s".', $type));
+              }
+
+              $this->raiseLintInLibrary(
+                $library,
+                $file,
+                $offset,
+                self::LINT_NONCANONICAL_SYMBOL,
+                $summary,
+                $symbol,
+                $proper_symbol);
+
+              continue;
+            }
+
+            $arcanist_root = dirname(phutil_get_library_root('arcanist'));
+
+            switch ($type) {
+              case 'class':
+                $summary = pht(
+                  'Use of unknown class symbol "%s".',
+                  $symbol);
+                break;
+              case 'function':
+                $summary = pht(
+                  'Use of unknown function symbol "%s".',
+                  $symbol);
+                break;
+              case 'interface':
+                $summary = pht(
+                  'Use of unknown interface symbol "%s".',
+                  $symbol);
+                break;
+              case 'class/interface':
+                $summary = pht(
+                  'Use of unknown class or interface symbol "%s".',
+                  $symbol);
+                break;
+            }
+
+            $details = pht(
+              "Common causes are:\n".
+              "\n".
+              "  - Your copy of Arcanist is out of date.\n".
+              "    This is the most common cause.\n".
+              "    Update this copy of Arcanist:\n".
+              "\n".
+              "      %s\n".
+              "\n".
+              "  - Some other library is out of date.\n".
+              "    Update the library this symbol appears in.\n".
+              "\n".
+              "  - The symbol is misspelled.\n".
+              "    Spell the symbol name correctly.\n".
+              "\n".
+              "  - You added the symbol recently, but have not updated\n".
+              "    the symbol map for the library.\n".
+              "    Run \"arc liberate\" in the library where the symbol is\n".
+              "    defined.\n".
+              "\n".
+              "  - This symbol is defined in an external library.\n".
+              "    Use \"@phutil-external-symbol\" to annotate it.\n".
+              "    Use \"grep\" to find examples of usage.",
+              $arcanist_root);
+
+            $message = implode(
+              "\n\n",
+              array(
+                $summary,
+                $details,
+              ));
 
             $this->raiseLintInLibrary(
               $library,
               $file,
               $offset,
               self::LINT_UNKNOWN_SYMBOL,
-              pht(
+              $message);
-                "Use of unknown %s '%s'. Common causes are:\n\n".
-                "  - Your %s is out of date.\n".
-                "    This is the most common cause.\n".
-                "    Update this copy of libphutil: %s\n\n".
-                "  - Some other library is out of date.\n".
-                "    Update the library this symbol appears in.\n\n".
-                "  - This symbol is misspelled.\n".
-                "    Spell the symbol name correctly.\n".
-                "    Symbol name spelling is case-sensitive.\n\n".
-                "  - This symbol was added recently.\n".
-                "    Run `%s` on the library it was added to.\n\n".
-                "  - This symbol is external. Use `%s`.\n".
-                "    Use `%s` to find usage examples of this directive.\n\n".
-                "*** ALTHOUGH USUALLY EASY TO FIX, THIS IS A SERIOUS ERROR.\n".
-                "*** THIS ERROR IS YOUR FAULT. YOU MUST RESOLVE IT.",
-                $type,
-                $symbol,
-                'libphutil/',
-                $libphutil_root,
-                'arc liberate',
-                '@phutil-external-symbol',
-                'grep'));
           }
         }
       }
     }
   }
 
-  private function raiseLintInLibrary($library, $path, $offset, $code, $desc) {
+  private function raiseLintInLibrary(
+    $library,
+    $path,
+    $offset,
+    $code,
+    $desc,
+    $original = null,
+    $replacement = null) {
     $root = phutil_get_library_root($library);
 
     $this->activePath = $root.'/'.$path;
-    $this->raiseLintAtOffset($offset, $code, $desc);
+    $this->raiseLintAtOffset($offset, $code, $desc, $original, $replacement);
   }
 
   public function lintPath($path) {
     return;
   }
 
+  private function normalizeSymbol($symbol) {
+    return phutil_utf8_strtolower($symbol);
+  }
+
 }

src/lint/linter/xhpast/rules/ArcanistInvalidModifiersXHPASTLinterRule.php

@@ -22,68 +22,65 @@ final class ArcanistInvalidModifiersXHPASTLinterRule
       $is_final    = false;
       $is_static   = false;
       $visibility  = null;
+      $is_property = ($method->getTypeName() == 'n_CLASS_MEMBER_MODIFIER_LIST');
+      $is_method = !$is_property;
+
+      $final_modifier = null;
+      $visibility_modifier = null;
+      $abstract_modifier = null;
 
       foreach ($modifiers as $modifier) {
         switch ($modifier->getConcreteString()) {
           case 'abstract':
-            if ($method->getTypeName() == 'n_CLASS_MEMBER_MODIFIER_LIST') {
+            if ($is_property) {
               $this->raiseLintAtNode(
                 $modifier,
                 pht(
-                  'Properties cannot be declared `%s`.',
+                  'Properties cannot be declared "abstract".'));
-                  'abstract'));
             }
 
             if ($is_abstract) {
               $this->raiseLintAtNode(
                 $modifier,
                 pht(
-                  'Multiple `%s` modifiers are not allowed.',
+                  'Multiple "abstract" modifiers are not allowed.'));
-                  'abstract'));
-            }
-
-            if ($is_final) {
-              $this->raiseLintAtNode(
-                $modifier,
-                pht(
-                'Cannot use the `%s` modifier on an `%s` class member',
-                'final',
-                'abstract'));
             }
 
+            $abstract_modifier = $modifier;
             $is_abstract = true;
             break;
 
           case 'final':
-            if ($is_abstract) {
+            if ($is_property) {
               $this->raiseLintAtNode(
                 $modifier,
                 pht(
-                'Cannot use the `%s` modifier on an `%s` class member',
+                  'Properties can not be declared "final".'));
-                'final',
-                'abstract'));
             }
 
             if ($is_final) {
               $this->raiseLintAtNode(
                 $modifier,
                 pht(
-                  'Multiple `%s` modifiers are not allowed.',
+                  'Multiple "final" modifiers are not allowed.'));
-                  'final'));
             }
 
+            $final_modifier = $modifier;
             $is_final = true;
             break;
           case 'public':
           case 'protected':
           case 'private':
-            if ($visibility) {
+            if ($visibility !== null) {
               $this->raiseLintAtNode(
                 $modifier,
                 pht('Multiple access type modifiers are not allowed.'));
             }
 
+            $visibility_modifier = $modifier;
+
             $visibility = $modifier->getConcreteString();
+            $visibility = phutil_utf8_strtolower($visibility);
             break;
 
           case 'static':
@@ -91,12 +88,47 @@ final class ArcanistInvalidModifiersXHPASTLinterRule
               $this->raiseLintAtNode(
                 $modifier,
                 pht(
-                  'Multiple `%s` modifiers are not allowed.',
+                  'Multiple "static" modifiers are not allowed.'));
-                  'static'));
             }
             break;
         }
       }
+
+      $is_private = ($visibility === 'private');
+
+      if ($is_final && $is_abstract) {
+        if ($is_method) {
+          $this->raiseLintAtNode(
+            $final_modifier,
+            pht('Methods may not be both "abstract" and "final".'));
+        } else {
+          // Properties can't be "abstract" and "final" either, but they can't
+          // ever be "abstract" at all, and we've already raise a message about
+          // that earlier.
+        }
+      }
+
+      if ($is_private && $is_final) {
+        if ($is_method) {
+          $final_tokens = $final_modifier->getTokens();
+          $space_tokens = last($final_tokens)->getWhitespaceTokensAfter();
+
+          $final_offset = head($final_tokens)->getOffset();
+
+          $final_string = array_merge($final_tokens, $space_tokens);
+          $final_string = mpull($final_string, 'getValue');
+          $final_string = implode('', $final_string);
+
+          $this->raiseLintAtOffset(
+            $final_offset,
+            pht('Methods may not be both "private" and "final".'),
+            $final_string,
+            '');
+        } else {
+          // Properties can't be "final" at all, and we already raised a
+          // message about this.
+        }
+      }
     }
   }
 

src/lint/linter/xhpast/rules/ArcanistPartialCatchXHPASTLinterRule.php

@@ -0,0 +1,45 @@
+<?php
+
+final class ArcanistPartialCatchXHPASTLinterRule
+  extends ArcanistXHPASTLinterRule {
+
+  const ID = 132;
+
+  public function getLintName() {
+    return pht('Partial Catch');
+  }
+
+  public function getLintSeverity() {
+    return ArcanistLintSeverity::SEVERITY_WARNING;
+  }
+
+  public function process(XHPASTNode $root) {
+    $catch_lists = $root->selectDescendantsOfType('n_CATCH_LIST');
+
+    foreach ($catch_lists as $catch_list) {
+      $catches = $catch_list->getChildrenOfType('n_CATCH');
+
+      $classes = array();
+      foreach ($catches as $catch) {
+        $class_node = $catch->getChildOfType(0, 'n_CLASS_NAME');
+        $class_name = $class_node->getConcreteString();
+        $class_name = phutil_utf8_strtolower($class_name);
+
+        $classes[$class_name] = $class_node;
+      }
+
+      $catches_exception = idx($classes, 'exception');
+      $catches_throwable = idx($classes, 'throwable');
+
+      if ($catches_exception && !$catches_throwable) {
+        $this->raiseLintAtNode(
+          $catches_exception,
+          pht(
+            'Try/catch block catches "Exception", but does not catch '.
+            '"Throwable". In PHP7 and newer, some runtime exceptions '.
+            'will escape this block.'));
+      }
+    }
+  }
+
+}

src/lint/linter/xhpast/rules/__tests__/ArcanistPartialCatchXHPASTLinterRuleTestCase.php

@@ -0,0 +1,10 @@
+<?php
+
+final class ArcanistPartialCatchXHPASTLinterRuleTestCase
+  extends ArcanistXHPASTLinterRuleTestCase {
+
+  public function testLinter() {
+    $this->executeTestsInDirectory(dirname(__FILE__).'/partial-catch/');
+  }
+
+}

src/lint/linter/xhpast/rules/__tests__/invalid-modifiers/invalid-modifiers.lint-test

@@ -5,14 +5,36 @@ class SomeClass {
   public public $b;
   public protected $c;
   private abstract $d;
+  private final $e;
 
   public function foo() {}
   public protected function bar() {}
   abstract final public function baz() {}
+  final private function wuff() {}
+  private final function fizz() {}
 }
 ~~~~~~~~~~
 error:5:10:XHP72:Invalid Modifiers
 error:6:10:XHP72:Invalid Modifiers
 error:7:11:XHP72:Invalid Modifiers
-error:10:10:XHP72:Invalid Modifiers
+error:8:11:XHP72:Invalid Modifiers
-error:11:12:XHP72:Invalid Modifiers
+error:11:10:XHP72:Invalid Modifiers
+error:12:12:XHP72:Invalid Modifiers
+error:13:3:XHP72:Invalid Modifiers
+error:14:11:XHP72:Invalid Modifiers
+~~~~~~~~~~
+<?php
+
+class SomeClass {
+  public $a;
+  public public $b;
+  public protected $c;
+  private abstract $d;
+  private final $e;
+
+  public function foo() {}
+  public protected function bar() {}
+  abstract final public function baz() {}
+  private function wuff() {}
+  private function fizz() {}
+}

src/lint/linter/xhpast/rules/__tests__/partial-catch/catch-without-throwable.lint-test

@@ -0,0 +1,17 @@
+<?php
+try {
+  f();
+} catch (Exception $ex) {
+  g();
+}
+
+try {
+  f();
+} catch (Exception $ex) {
+  g();
+} catch (Throwable $ex) {
+  h();
+}
+
+~~~~~~~~~~
+warning:4:10:XHP132

src/moduleutils/PhutilLibraryMapBuilder.php

@@ -266,9 +266,29 @@ final class PhutilLibraryMapBuilder extends Phobject {
    */
   private function buildSymbolAnalysisFuture($file) {
     $absolute_file = $this->getPath($file);
+    return self::newExtractSymbolsFuture(
+      array(),
+      array($absolute_file));
+  }
+
+  private static function newExtractSymbolsFuture(array $flags, array $paths) {
     $bin = dirname(__FILE__).'/../../support/lib/extract-symbols.php';
 
-    return new ExecFuture('php -f %R -- --ugly %R', $bin, $absolute_file);
+    return new ExecFuture(
+      'php -f %R -- --ugly %Ls -- %Ls',
+      $bin,
+      $flags,
+      $paths);
+  }
+
+  public static function newBuiltinMap() {
+    $future = self::newExtractSymbolsFuture(
+      array('--builtins'),
+      array());
+
+    list($json) = $future->resolvex();
+
+    return phutil_json_decode($json);
   }
 
 

src/parser/aast/api/AASTToken.php

@@ -84,6 +84,17 @@ abstract class AASTToken extends Phobject {
     return $result;
   }
 
+  public function getWhitespaceTokensAfter() {
+    $tokens = $this->tree->getRawTokenStream();
+    $result = array();
+    $ii = $this->id + 1;
+    while ($ii < count($tokens) && $tokens[$ii]->isAnyWhitespace()) {
+      $result[$ii] = $tokens[$ii];
+      ++$ii;
+    }
+    return $result;
+  }
+
   final public function getLineNumber() {
     return idx($this->tree->getOffsetToLineNumberMap(), $this->getOffset());
   }

src/xsprintf/xsprintf.php

@@ -67,6 +67,18 @@ function xsprintf($callback, $userdata, array $argv) {
         }
 
         if ($callback !== null) {
+
+          // See T13588 and D21500. This function uses "$callback()", instead
+          // of "call_user_func()", to simplify reference behavior: some of
+          // these arguments must be passed by reference.
+
+          // Prior to PHP7, this syntax will not work if "$callback" is a
+          // string referencing a static method, like "C::m".
+
+          // This syntax does work if "$callback" is an array referencing
+          // a static method, like "array('C', 'm')", in all versions of PHP
+          // since PHP 5.4.
+
           $callback($userdata, $pattern, $pos, $argv[$arg], $len);
         }
       }

support/lib/extract-symbols.php

@@ -23,8 +23,8 @@ $args->setSynopsis(<<<EOHELP
 
         Symbols are reported in JSON on stdout.
 
-        This script is used internally by libphutil/arcanist to build maps of
+        This script is used internally by Arcanist to build maps of library
-        library symbols.
+        symbols.
 
         It would be nice to eventually implement this as a C++ xhpast binary,
         as it's relatively stable and performance is currently awful
@@ -38,7 +38,11 @@ $args->parse(
     array(
       'name'      => 'all',
       'help'      => pht(
-        'Report all symbols, including built-ins and declared externals.'),
+        'Emit all symbols, including built-ins and declared externals.'),
+    ),
+    array(
+      'name' => 'builtins',
+      'help' => pht('Emit builtin symbols.'),
     ),
     array(
       'name'      => 'ugly',
@@ -52,14 +56,32 @@ $args->parse(
   ));
 
 $paths = $args->getArg('path');
-if (count($paths) !== 1) {
-  throw new Exception(pht('Specify exactly one path!'));
-}
-$path = Filesystem::resolvePath(head($paths));
 
 $show_all = $args->getArg('all');
+$show_builtins = $args->getArg('builtins');
 
-$source_code = Filesystem::readFile($path);
+if ($show_all && $show_builtins) {
+  throw new PhutilArgumentUsageException(
+    pht(
+      'Flags "--all" and "--builtins" are not compatible.'));
+}
+
+if ($show_builtins && $paths) {
+  throw new PhutilArgumentUsageException(
+    pht(
+      'Flag "--builtins" may not be used with a path.'));
+}
+
+if ($show_builtins) {
+  $path = '<builtins>';
+  $source_code = '';
+} else {
+  if (count($paths) !== 1) {
+    throw new Exception(pht('Specify exactly one path!'));
+  }
+  $path = Filesystem::resolvePath(head($paths));
+  $source_code = Filesystem::readFile($path);
+}
 
 try {
   $tree = XHPASTTree::newFromData($source_code);
@@ -474,6 +496,14 @@ foreach ($need as $key => $spec) {
   $required_symbols[$type][$name] = $spec['symbol']->getOffset();
 }
 
+if ($show_builtins) {
+  foreach ($builtins as $type => $builtin_symbols) {
+    foreach ($builtin_symbols as $builtin_symbol => $ignored) {
+      $declared_symbols[$type][$builtin_symbol] = null;
+    }
+  }
+}
+
 $result = array(
   'have'  => $declared_symbols,
   'need'  => $required_symbols,
@@ -543,8 +573,6 @@ function phutil_symbols_get_builtins() {
       'parent' => true,
       'self'   => true,
 
-      'PhutilBootloader' => true,
-
       // PHP7 defines these new parent classes of "Exception", but they do not
       // exist prior to PHP7. It's possible to use them safely in PHP5, in
       // some cases, to write code which is compatible with either PHP5 or
@@ -570,12 +598,6 @@ function phutil_symbols_get_builtins() {
         'isset' => true,
         'die'   => true,
 
-        // These are provided by libphutil but not visible in the map.
-
-        'phutil_is_windows'   => true,
-        'phutil_load_library' => true,
-        'phutil_is_hiphop_runtime' => true,
-
         // HPHP/i defines these functions as 'internal', but they are NOT
         // builtins and do not exist in vanilla PHP. Make sure we don't mark
         // them as builtin since we need to add dependencies for them.