<?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;
}
}