1: | <?php declare(strict_types = 1); |
2: | |
3: | namespace PHPStan\Type\Generic; |
4: | |
5: | use PHPStan\PhpDocParser\Ast\Type\GenericTypeNode; |
6: | use PHPStan\ShouldNotHappenException; |
7: | use PHPStan\TrinaryLogic; |
8: | use PHPStan\Type\AcceptsResult; |
9: | use PHPStan\Type\BenevolentUnionType; |
10: | use PHPStan\Type\MixedType; |
11: | use PHPStan\Type\NeverType; |
12: | use PHPStan\Type\Type; |
13: | use function sprintf; |
14: | |
15: | |
16: | |
17: | |
18: | |
19: | class TemplateTypeVariance |
20: | { |
21: | |
22: | private const INVARIANT = 1; |
23: | private const COVARIANT = 2; |
24: | private const CONTRAVARIANT = 3; |
25: | private const STATIC = 4; |
26: | private const BIVARIANT = 5; |
27: | |
28: | |
29: | private static array $registry; |
30: | |
31: | private static bool $invarianceCompositionEnabled = false; |
32: | |
33: | private function __construct(private int $value) |
34: | { |
35: | } |
36: | |
37: | private static function create(int $value): self |
38: | { |
39: | self::$registry[$value] ??= new self($value); |
40: | return self::$registry[$value]; |
41: | } |
42: | |
43: | public static function createInvariant(): self |
44: | { |
45: | return self::create(self::INVARIANT); |
46: | } |
47: | |
48: | public static function createCovariant(): self |
49: | { |
50: | return self::create(self::COVARIANT); |
51: | } |
52: | |
53: | public static function createContravariant(): self |
54: | { |
55: | return self::create(self::CONTRAVARIANT); |
56: | } |
57: | |
58: | public static function createStatic(): self |
59: | { |
60: | return self::create(self::STATIC); |
61: | } |
62: | |
63: | public static function createBivariant(): self |
64: | { |
65: | return self::create(self::BIVARIANT); |
66: | } |
67: | |
68: | public function invariant(): bool |
69: | { |
70: | return $this->value === self::INVARIANT; |
71: | } |
72: | |
73: | public function covariant(): bool |
74: | { |
75: | return $this->value === self::COVARIANT; |
76: | } |
77: | |
78: | public function contravariant(): bool |
79: | { |
80: | return $this->value === self::CONTRAVARIANT; |
81: | } |
82: | |
83: | public function static(): bool |
84: | { |
85: | return $this->value === self::STATIC; |
86: | } |
87: | |
88: | public function bivariant(): bool |
89: | { |
90: | return $this->value === self::BIVARIANT; |
91: | } |
92: | |
93: | public function compose(self $other): self |
94: | { |
95: | if ($this->contravariant()) { |
96: | if ($other->contravariant()) { |
97: | return self::createCovariant(); |
98: | } |
99: | if ($other->covariant()) { |
100: | return self::createContravariant(); |
101: | } |
102: | if ($other->bivariant()) { |
103: | return self::createBivariant(); |
104: | } |
105: | return self::createInvariant(); |
106: | } |
107: | |
108: | if ($this->covariant()) { |
109: | if ($other->contravariant()) { |
110: | return self::createContravariant(); |
111: | } |
112: | if ($other->covariant()) { |
113: | return self::createCovariant(); |
114: | } |
115: | if ($other->bivariant()) { |
116: | return self::createBivariant(); |
117: | } |
118: | return self::createInvariant(); |
119: | } |
120: | |
121: | if (self::$invarianceCompositionEnabled && $this->invariant()) { |
122: | return self::createInvariant(); |
123: | } |
124: | |
125: | if ($this->bivariant()) { |
126: | return self::createBivariant(); |
127: | } |
128: | |
129: | return $other; |
130: | } |
131: | |
132: | public function isValidVariance(Type $a, Type $b): TrinaryLogic |
133: | { |
134: | return $this->isValidVarianceWithReason(null, $a, $b)->result; |
135: | } |
136: | |
137: | public function isValidVarianceWithReason(?TemplateType $templateType, Type $a, Type $b): AcceptsResult |
138: | { |
139: | if ($b instanceof NeverType) { |
140: | return AcceptsResult::createYes(); |
141: | } |
142: | |
143: | if ($a instanceof MixedType && !$a instanceof TemplateType) { |
144: | return AcceptsResult::createYes(); |
145: | } |
146: | |
147: | if ($a instanceof BenevolentUnionType) { |
148: | if (!$a->isSuperTypeOf($b)->no()) { |
149: | return AcceptsResult::createYes(); |
150: | } |
151: | } |
152: | |
153: | if ($b instanceof BenevolentUnionType) { |
154: | if (!$b->isSuperTypeOf($a)->no()) { |
155: | return AcceptsResult::createYes(); |
156: | } |
157: | } |
158: | |
159: | if ($b instanceof MixedType && !$b instanceof TemplateType) { |
160: | return AcceptsResult::createYes(); |
161: | } |
162: | |
163: | if ($this->invariant()) { |
164: | $result = $a->equals($b); |
165: | $reasons = []; |
166: | if (!$result) { |
167: | if ( |
168: | $templateType !== null |
169: | && $templateType->getScope()->getClassName() !== null |
170: | && $a->isSuperTypeOf($b)->yes() |
171: | ) { |
172: | $reasons[] = sprintf( |
173: | 'Template type %s on class %s is not covariant. Learn more: <fg=cyan>https://phpstan.org/blog/whats-up-with-template-covariant</>', |
174: | $templateType->getName(), |
175: | $templateType->getScope()->getClassName(), |
176: | ); |
177: | } |
178: | } |
179: | |
180: | return new AcceptsResult(TrinaryLogic::createFromBoolean($result), $reasons); |
181: | } |
182: | |
183: | if ($this->covariant()) { |
184: | return new AcceptsResult($a->isSuperTypeOf($b), []); |
185: | } |
186: | |
187: | if ($this->contravariant()) { |
188: | return new AcceptsResult($b->isSuperTypeOf($a), []); |
189: | } |
190: | |
191: | if ($this->bivariant()) { |
192: | return AcceptsResult::createYes(); |
193: | } |
194: | |
195: | throw new ShouldNotHappenException(); |
196: | } |
197: | |
198: | public function equals(self $other): bool |
199: | { |
200: | return $other->value === $this->value; |
201: | } |
202: | |
203: | public function validPosition(self $other): bool |
204: | { |
205: | return $other->value === $this->value |
206: | || $other->invariant() |
207: | || $this->bivariant() |
208: | || $this->static(); |
209: | } |
210: | |
211: | public function describe(): string |
212: | { |
213: | switch ($this->value) { |
214: | case self::INVARIANT: |
215: | return 'invariant'; |
216: | case self::COVARIANT: |
217: | return 'covariant'; |
218: | case self::CONTRAVARIANT: |
219: | return 'contravariant'; |
220: | case self::STATIC: |
221: | return 'static'; |
222: | case self::BIVARIANT: |
223: | return 'bivariant'; |
224: | } |
225: | |
226: | throw new ShouldNotHappenException(); |
227: | } |
228: | |
229: | |
230: | |
231: | |
232: | public function toPhpDocNodeVariance(): string |
233: | { |
234: | switch ($this->value) { |
235: | case self::INVARIANT: |
236: | return GenericTypeNode::VARIANCE_INVARIANT; |
237: | case self::COVARIANT: |
238: | return GenericTypeNode::VARIANCE_COVARIANT; |
239: | case self::CONTRAVARIANT: |
240: | return GenericTypeNode::VARIANCE_CONTRAVARIANT; |
241: | case self::BIVARIANT: |
242: | return GenericTypeNode::VARIANCE_BIVARIANT; |
243: | } |
244: | |
245: | throw new ShouldNotHappenException(); |
246: | } |
247: | |
248: | |
249: | |
250: | |
251: | public static function __set_state(array $properties): self |
252: | { |
253: | return new self($properties['value']); |
254: | } |
255: | |
256: | public static function setInvarianceCompositionEnabled(bool $enabled): void |
257: | { |
258: | self::$invarianceCompositionEnabled = $enabled; |
259: | } |
260: | |
261: | } |
262: | |