1: <?php declare(strict_types=1);
2:
3: namespace PhpParser;
4:
5: use PhpParser\Node\Name;
6: use PhpParser\Node\Name\FullyQualified;
7: use PhpParser\Node\Stmt;
8:
9: class NameContext
10: {
11: /** @var null|Name Current namespace */
12: protected $namespace;
13:
14: /** @var Name[][] Map of format [aliasType => [aliasName => originalName]] */
15: protected $aliases = [];
16:
17: /** @var Name[][] Same as $aliases but preserving original case */
18: protected $origAliases = [];
19:
20: /** @var ErrorHandler Error handler */
21: protected $errorHandler;
22:
23: /**
24: * Create a name context.
25: *
26: * @param ErrorHandler $errorHandler Error handling used to report errors
27: */
28: public function __construct(ErrorHandler $errorHandler) {
29: $this->errorHandler = $errorHandler;
30: }
31:
32: /**
33: * Start a new namespace.
34: *
35: * This also resets the alias table.
36: *
37: * @param Name|null $namespace Null is the global namespace
38: */
39: public function startNamespace(?Name $namespace = null) {
40: $this->namespace = $namespace;
41: $this->origAliases = $this->aliases = [
42: Stmt\Use_::TYPE_NORMAL => [],
43: Stmt\Use_::TYPE_FUNCTION => [],
44: Stmt\Use_::TYPE_CONSTANT => [],
45: ];
46: }
47:
48: /**
49: * Add an alias / import.
50: *
51: * @param Name $name Original name
52: * @param string $aliasName Aliased name
53: * @param int $type One of Stmt\Use_::TYPE_*
54: * @param array $errorAttrs Attributes to use to report an error
55: */
56: public function addAlias(Name $name, string $aliasName, int $type, array $errorAttrs = []) {
57: // Constant names are case sensitive, everything else case insensitive
58: if ($type === Stmt\Use_::TYPE_CONSTANT) {
59: $aliasLookupName = $aliasName;
60: } else {
61: $aliasLookupName = strtolower($aliasName);
62: }
63:
64: if (isset($this->aliases[$type][$aliasLookupName])) {
65: $typeStringMap = [
66: Stmt\Use_::TYPE_NORMAL => '',
67: Stmt\Use_::TYPE_FUNCTION => 'function ',
68: Stmt\Use_::TYPE_CONSTANT => 'const ',
69: ];
70:
71: $this->errorHandler->handleError(new Error(
72: sprintf(
73: 'Cannot use %s%s as %s because the name is already in use',
74: $typeStringMap[$type], $name, $aliasName
75: ),
76: $errorAttrs
77: ));
78: return;
79: }
80:
81: $this->aliases[$type][$aliasLookupName] = $name;
82: $this->origAliases[$type][$aliasName] = $name;
83: }
84:
85: /**
86: * Get current namespace.
87: *
88: * @return null|Name Namespace (or null if global namespace)
89: */
90: public function getNamespace() {
91: return $this->namespace;
92: }
93:
94: /**
95: * Get resolved name.
96: *
97: * @param Name $name Name to resolve
98: * @param int $type One of Stmt\Use_::TYPE_{FUNCTION|CONSTANT}
99: *
100: * @return null|Name Resolved name, or null if static resolution is not possible
101: */
102: public function getResolvedName(Name $name, int $type) {
103: // don't resolve special class names
104: if ($type === Stmt\Use_::TYPE_NORMAL && $name->isSpecialClassName()) {
105: if (!$name->isUnqualified()) {
106: $this->errorHandler->handleError(new Error(
107: sprintf("'\\%s' is an invalid class name", $name->toString()),
108: $name->getAttributes()
109: ));
110: }
111: return $name;
112: }
113:
114: // fully qualified names are already resolved
115: if ($name->isFullyQualified()) {
116: return $name;
117: }
118:
119: // Try to resolve aliases
120: if (null !== $resolvedName = $this->resolveAlias($name, $type)) {
121: return $resolvedName;
122: }
123:
124: if ($type !== Stmt\Use_::TYPE_NORMAL && $name->isUnqualified()) {
125: if (null === $this->namespace) {
126: // outside of a namespace unaliased unqualified is same as fully qualified
127: return new FullyQualified($name, $name->getAttributes());
128: }
129:
130: // Cannot resolve statically
131: return null;
132: }
133:
134: // if no alias exists prepend current namespace
135: return FullyQualified::concat($this->namespace, $name, $name->getAttributes());
136: }
137:
138: /**
139: * Get resolved class name.
140: *
141: * @param Name $name Class ame to resolve
142: *
143: * @return Name Resolved name
144: */
145: public function getResolvedClassName(Name $name) : Name {
146: return $this->getResolvedName($name, Stmt\Use_::TYPE_NORMAL);
147: }
148:
149: /**
150: * Get possible ways of writing a fully qualified name (e.g., by making use of aliases).
151: *
152: * @param string $name Fully-qualified name (without leading namespace separator)
153: * @param int $type One of Stmt\Use_::TYPE_*
154: *
155: * @return Name[] Possible representations of the name
156: */
157: public function getPossibleNames(string $name, int $type) : array {
158: $lcName = strtolower($name);
159:
160: if ($type === Stmt\Use_::TYPE_NORMAL) {
161: // self, parent and static must always be unqualified
162: if ($lcName === "self" || $lcName === "parent" || $lcName === "static") {
163: return [new Name($name)];
164: }
165: }
166:
167: // Collect possible ways to write this name, starting with the fully-qualified name
168: $possibleNames = [new FullyQualified($name)];
169:
170: if (null !== $nsRelativeName = $this->getNamespaceRelativeName($name, $lcName, $type)) {
171: // Make sure there is no alias that makes the normally namespace-relative name
172: // into something else
173: if (null === $this->resolveAlias($nsRelativeName, $type)) {
174: $possibleNames[] = $nsRelativeName;
175: }
176: }
177:
178: // Check for relevant namespace use statements
179: foreach ($this->origAliases[Stmt\Use_::TYPE_NORMAL] as $alias => $orig) {
180: $lcOrig = $orig->toLowerString();
181: if (0 === strpos($lcName, $lcOrig . '\\')) {
182: $possibleNames[] = new Name($alias . substr($name, strlen($lcOrig)));
183: }
184: }
185:
186: // Check for relevant type-specific use statements
187: foreach ($this->origAliases[$type] as $alias => $orig) {
188: if ($type === Stmt\Use_::TYPE_CONSTANT) {
189: // Constants are are complicated-sensitive
190: $normalizedOrig = $this->normalizeConstName($orig->toString());
191: if ($normalizedOrig === $this->normalizeConstName($name)) {
192: $possibleNames[] = new Name($alias);
193: }
194: } else {
195: // Everything else is case-insensitive
196: if ($orig->toLowerString() === $lcName) {
197: $possibleNames[] = new Name($alias);
198: }
199: }
200: }
201:
202: return $possibleNames;
203: }
204:
205: /**
206: * Get shortest representation of this fully-qualified name.
207: *
208: * @param string $name Fully-qualified name (without leading namespace separator)
209: * @param int $type One of Stmt\Use_::TYPE_*
210: *
211: * @return Name Shortest representation
212: */
213: public function getShortName(string $name, int $type) : Name {
214: $possibleNames = $this->getPossibleNames($name, $type);
215:
216: // Find shortest name
217: $shortestName = null;
218: $shortestLength = \INF;
219: foreach ($possibleNames as $possibleName) {
220: $length = strlen($possibleName->toCodeString());
221: if ($length < $shortestLength) {
222: $shortestName = $possibleName;
223: $shortestLength = $length;
224: }
225: }
226:
227: return $shortestName;
228: }
229:
230: private function resolveAlias(Name $name, $type) {
231: $firstPart = $name->getFirst();
232:
233: if ($name->isQualified()) {
234: // resolve aliases for qualified names, always against class alias table
235: $checkName = strtolower($firstPart);
236: if (isset($this->aliases[Stmt\Use_::TYPE_NORMAL][$checkName])) {
237: $alias = $this->aliases[Stmt\Use_::TYPE_NORMAL][$checkName];
238: return FullyQualified::concat($alias, $name->slice(1), $name->getAttributes());
239: }
240: } elseif ($name->isUnqualified()) {
241: // constant aliases are case-sensitive, function aliases case-insensitive
242: $checkName = $type === Stmt\Use_::TYPE_CONSTANT ? $firstPart : strtolower($firstPart);
243: if (isset($this->aliases[$type][$checkName])) {
244: // resolve unqualified aliases
245: return new FullyQualified($this->aliases[$type][$checkName], $name->getAttributes());
246: }
247: }
248:
249: // No applicable aliases
250: return null;
251: }
252:
253: private function getNamespaceRelativeName(string $name, string $lcName, int $type) {
254: if (null === $this->namespace) {
255: return new Name($name);
256: }
257:
258: if ($type === Stmt\Use_::TYPE_CONSTANT) {
259: // The constants true/false/null always resolve to the global symbols, even inside a
260: // namespace, so they may be used without qualification
261: if ($lcName === "true" || $lcName === "false" || $lcName === "null") {
262: return new Name($name);
263: }
264: }
265:
266: $namespacePrefix = strtolower($this->namespace . '\\');
267: if (0 === strpos($lcName, $namespacePrefix)) {
268: return new Name(substr($name, strlen($namespacePrefix)));
269: }
270:
271: return null;
272: }
273:
274: private function normalizeConstName(string $name) {
275: $nsSep = strrpos($name, '\\');
276: if (false === $nsSep) {
277: return $name;
278: }
279:
280: // Constants have case-insensitive namespace and case-sensitive short-name
281: $ns = substr($name, 0, $nsSep);
282: $shortName = substr($name, $nsSep + 1);
283: return strtolower($ns) . '\\' . $shortName;
284: }
285: }
286: