comparison vendor/nikic/php-parser/lib/PhpParser/NameContext.php @ 13:5fb285c0d0e3

Update Drupal core to 8.4.7 via Composer. Security update; I *think* we've
been lucky to get away with this so far, as we don't support self-registration
which seems to be used by the so-called "drupalgeddon 2" attack that 8.4.5
was vulnerable to.

+<?php declare(strict_types=1);
+
+namespace PhpParser;
+
+use PhpParser\Node\Name;
+use PhpParser\Node\Name\FullyQualified;
+use PhpParser\Node\Stmt;
+
+class NameContext
+{
+    /** @var null|Name Current namespace */
+    protected $namespace;
+
+    /** @var Name[][] Map of format [aliasType => [aliasName => originalName]] */
+    protected $aliases = [];
+
+    /** @var Name[][] Same as $aliases but preserving original case */
+    protected $origAliases = [];
+
+    /** @var ErrorHandler Error handler */
+    protected $errorHandler;
+
+    /**
+     * Create a name context.
+     *
+     * @param ErrorHandler $errorHandler Error handling used to report errors
+     */
+    public function __construct(ErrorHandler $errorHandler) {
+        $this->errorHandler = $errorHandler;
+    }
+
+    /**
+     * Start a new namespace.
+     *
+     * This also resets the alias table.
+     *
+     * @param Name|null $namespace Null is the global namespace
+     */
+    public function startNamespace(Name $namespace = null) {
+        $this->namespace = $namespace;
+        $this->origAliases = $this->aliases = [
+            Stmt\Use_::TYPE_NORMAL   => [],
+            Stmt\Use_::TYPE_FUNCTION => [],
+            Stmt\Use_::TYPE_CONSTANT => [],
+        ];
+    }
+
+    /**
+     * Add an alias / import.
+     *
+     * @param Name   $name        Original name
+     * @param string $aliasName   Aliased name
+     * @param int    $type        One of Stmt\Use_::TYPE_*
+     * @param array  $errorAttrs Attributes to use to report an error
+     */
+    public function addAlias(Name $name, string $aliasName, int $type, array $errorAttrs = []) {
+        // Constant names are case sensitive, everything else case insensitive
+        if ($type === Stmt\Use_::TYPE_CONSTANT) {
+            $aliasLookupName = $aliasName;
+        } else {
+            $aliasLookupName = strtolower($aliasName);
+        }
+
+        if (isset($this->aliases[$type][$aliasLookupName])) {
+            $typeStringMap = [
+                Stmt\Use_::TYPE_NORMAL   => '',
+                Stmt\Use_::TYPE_FUNCTION => 'function ',
+                Stmt\Use_::TYPE_CONSTANT => 'const ',
+            ];
+
+            $this->errorHandler->handleError(new Error(
+                sprintf(
+                    'Cannot use %s%s as %s because the name is already in use',
+                    $typeStringMap[$type], $name, $aliasName
+                ),
+                $errorAttrs
+            ));
+            return;
+        }
+
+        $this->aliases[$type][$aliasLookupName] = $name;
+        $this->origAliases[$type][$aliasName] = $name;
+    }
+
+    /**
+     * Get current namespace.
+     *
+     * @return null|Name Namespace (or null if global namespace)
+     */
+    public function getNamespace() {
+        return $this->namespace;
+    }
+
+    /**
+     * Get resolved name.
+     *
+     * @param Name $name Name to resolve
+     * @param int  $type One of Stmt\Use_::TYPE_{FUNCTION|CONSTANT}
+     *
+     * @return null|Name Resolved name, or null if static resolution is not possible
+     */
+    public function getResolvedName(Name $name, int $type) {
+        // don't resolve special class names
+        if ($type === Stmt\Use_::TYPE_NORMAL && $name->isSpecialClassName()) {
+            if (!$name->isUnqualified()) {
+                $this->errorHandler->handleError(new Error(
+                    sprintf("'\\%s' is an invalid class name", $name->toString()),
+                    $name->getAttributes()
+                ));
+            }
+            return $name;
+        }
+
+        // fully qualified names are already resolved
+        if ($name->isFullyQualified()) {
+            return $name;
+        }
+
+        // Try to resolve aliases
+        if (null !== $resolvedName = $this->resolveAlias($name, $type)) {
+            return $resolvedName;
+        }
+
+        if ($type !== Stmt\Use_::TYPE_NORMAL && $name->isUnqualified()) {
+            if (null === $this->namespace) {
+                // outside of a namespace unaliased unqualified is same as fully qualified
+                return new FullyQualified($name, $name->getAttributes());
+            }
+
+            // Cannot resolve statically
+            return null;
+        }
+
+        // if no alias exists prepend current namespace
+        return FullyQualified::concat($this->namespace, $name, $name->getAttributes());
+    }
+
+    /**
+     * Get resolved class name.
+     *
+     * @param Name $name Class ame to resolve
+     *
+     * @return Name Resolved name
+     */
+    public function getResolvedClassName(Name $name) : Name {
+        return $this->getResolvedName($name, Stmt\Use_::TYPE_NORMAL);
+    }
+
+    /**
+     * Get possible ways of writing a fully qualified name (e.g., by making use of aliases).
+     *
+     * @param string $name Fully-qualified name (without leading namespace separator)
+     * @param int    $type One of Stmt\Use_::TYPE_*
+     *
+     * @return Name[] Possible representations of the name
+     */
+    public function getPossibleNames(string $name, int $type) : array {
+        $lcName = strtolower($name);
+
+        if ($type === Stmt\Use_::TYPE_NORMAL) {
+            // self, parent and static must always be unqualified
+            if ($lcName === "self" || $lcName === "parent" || $lcName === "static") {
+                return [new Name($name)];
+            }
+        }
+
+        // Collect possible ways to write this name, starting with the fully-qualified name
+        $possibleNames = [new FullyQualified($name)];
+
+        if (null !== $nsRelativeName = $this->getNamespaceRelativeName($name, $lcName, $type)) {
+            // Make sure there is no alias that makes the normally namespace-relative name
+            // into something else
+            if (null === $this->resolveAlias($nsRelativeName, $type)) {
+                $possibleNames[] = $nsRelativeName;
+            }
+        }
+
+        // Check for relevant namespace use statements
+        foreach ($this->origAliases[Stmt\Use_::TYPE_NORMAL] as $alias => $orig) {
+            $lcOrig = $orig->toLowerString();
+            if (0 === strpos($lcName, $lcOrig . '\\')) {
+                $possibleNames[] = new Name($alias . substr($name, strlen($lcOrig)));
+            }
+        }
+
+        // Check for relevant type-specific use statements
+        foreach ($this->origAliases[$type] as $alias => $orig) {
+            if ($type === Stmt\Use_::TYPE_CONSTANT) {
+                // Constants are are complicated-sensitive
+                $normalizedOrig = $this->normalizeConstName($orig->toString());
+                if ($normalizedOrig === $this->normalizeConstName($name)) {
+                    $possibleNames[] = new Name($alias);
+                }
+            } else {
+                // Everything else is case-insensitive
+                if ($orig->toLowerString() === $lcName) {
+                    $possibleNames[] = new Name($alias);
+                }
+            }
+        }
+
+        return $possibleNames;
+    }
+
+    /**
+     * Get shortest representation of this fully-qualified name.
+     *
+     * @param string $name Fully-qualified name (without leading namespace separator)
+     * @param int    $type One of Stmt\Use_::TYPE_*
+     *
+     * @return Name Shortest representation
+     */
+    public function getShortName(string $name, int $type) : Name {
+        $possibleNames = $this->getPossibleNames($name, $type);
+
+        // Find shortest name
+        $shortestName = null;
+        $shortestLength = \INF;
+        foreach ($possibleNames as $possibleName) {
+            $length = strlen($possibleName->toCodeString());
+            if ($length < $shortestLength) {
+                $shortestName = $possibleName;
+                $shortestLength = $length;
+            }
+        }
+
+       return $shortestName;
+    }
+
+    private function resolveAlias(Name $name, $type) {
+        $firstPart = $name->getFirst();
+
+        if ($name->isQualified()) {
+            // resolve aliases for qualified names, always against class alias table
+            $checkName = strtolower($firstPart);
+            if (isset($this->aliases[Stmt\Use_::TYPE_NORMAL][$checkName])) {
+                $alias = $this->aliases[Stmt\Use_::TYPE_NORMAL][$checkName];
+                return FullyQualified::concat($alias, $name->slice(1), $name->getAttributes());
+            }
+        } elseif ($name->isUnqualified()) {
+            // constant aliases are case-sensitive, function aliases case-insensitive
+            $checkName = $type === Stmt\Use_::TYPE_CONSTANT ? $firstPart : strtolower($firstPart);
+            if (isset($this->aliases[$type][$checkName])) {
+                // resolve unqualified aliases
+                return new FullyQualified($this->aliases[$type][$checkName], $name->getAttributes());
+            }
+        }
+
+        // No applicable aliases
+        return null;
+    }
+
+    private function getNamespaceRelativeName(string $name, string $lcName, int $type) {
+        if (null === $this->namespace) {
+            return new Name($name);
+        }
+
+        if ($type === Stmt\Use_::TYPE_CONSTANT) {
+            // The constants true/false/null always resolve to the global symbols, even inside a
+            // namespace, so they may be used without qualification
+            if ($lcName === "true" || $lcName === "false" || $lcName === "null") {
+                return new Name($name);
+            }
+        }
+
+        $namespacePrefix = strtolower($this->namespace . '\\');
+        if (0 === strpos($lcName, $namespacePrefix)) {
+            return new Name(substr($name, strlen($namespacePrefix)));
+        }
+
+        return null;
+    }
+
+    private function normalizeConstName(string $name) {
+        $nsSep = strrpos($name, '\\');
+        if (false === $nsSep) {
+            return $name;
+        }
+
+        // Constants have case-insensitive namespace and case-sensitive short-name
+        $ns = substr($name, 0, $nsSep);
+        $shortName = substr($name, $nsSep + 1);
+        return strtolower($ns) . '\\' . $shortName;
+    }
+}