packages/deriver/tests/Unit/Deriver/Lowerer/Control/LoopLoweringTest.php

1<?php
2
3declare (strict_types=1);
4
5namespace Tests\Unit\Deriver\Lowerer\Control;
6
7use Deriver\Deriver;
8use Deriver\Deriver\Candidate\ResultRef;
9use Deriver\Deriver\Candidate\Snapshot;
10use Deriver\Deriver\Candidate\Statistics;
11use Deriver\Deriver\Contributions;
12use Deriver\Deriver\DeriverConfig;
13use Deriver\Deriver\Evaluator\Call\Evaluators;
14use Deriver\Deriver\Evaluator\Call\Extensions;
15use Deriver\Deriver\Evaluator\Call\Registrations;
16use Deriver\Deriver\Evaluator\Call\StateRegistry;
17use Deriver\Deriver\Evaluator\EvaluatorConfig;
18use Deriver\Deriver\Evaluator\Evidence\Frontier;
19use Deriver\Deriver\Evaluator\Execution\Call\ArgumentBinding;
20use Deriver\Deriver\Evaluator\Execution\Call\ArgumentOrder;
21use Deriver\Deriver\Evaluator\Execution\Call\CallableCheck;
22use Deriver\Deriver\Evaluator\Execution\Call\CallExecutor;
23use Deriver\Deriver\Evaluator\Execution\Call\CallResolution;
24use Deriver\Deriver\Evaluator\Execution\Call\Preparation\Resolution;
25use Deriver\Deriver\Evaluator\Execution\Call\Preparation\Target;
26use Deriver\Deriver\Evaluator\Execution\Call\Preparation\Transfer;
27use Deriver\Deriver\Evaluator\Execution\Call\TypeBinding;
28use Deriver\Deriver\Evaluator\Execution\Call\TypeCheck;
29use Deriver\Deriver\Evaluator\Execution\Completion\Alternative;
30use Deriver\Deriver\Evaluator\Execution\Completion\Assessment;
31use Deriver\Deriver\Evaluator\Execution\Completion\Completion;
32use Deriver\Deriver\Evaluator\Execution\Completion\Exceptional;
33use Deriver\Deriver\Evaluator\Execution\Completion\StorageSnapshot;
34use Deriver\Deriver\Evaluator\Execution\Constraints;
35use Deriver\Deriver\Evaluator\Execution\Context;
36use Deriver\Deriver\Evaluator\Execution\Control\IterationStep;
37use Deriver\Deriver\Evaluator\Execution\Control\IteratorCursor;
38use Deriver\Deriver\Evaluator\Execution\Control\LoopConvergence;
39use Deriver\Deriver\Evaluator\Execution\Control\ObservationLimit;
40use Deriver\Deriver\Evaluator\Execution\Control\StateJoin;
41use Deriver\Deriver\Evaluator\Execution\Control\Unwinding;
42use Deriver\Deriver\Evaluator\Execution\Demand\Cell;
43use Deriver\Deriver\Evaluator\Execution\Demand\Components;
44use Deriver\Deriver\Evaluator\Execution\Demand\Discovery;
45use Deriver\Deriver\Evaluator\Execution\Demand\Key;
46use Deriver\Deriver\Evaluator\Execution\Demand\Table;
47use Deriver\Deriver\Evaluator\Execution\Dependencies;
48use Deriver\Deriver\Evaluator\Execution\Evaluator;
49use Deriver\Deriver\Evaluator\Execution\EvaluatorConfig as ExecutionEvaluatorConfig;
50use Deriver\Deriver\Evaluator\Execution\InstructionTransfer;
51use Deriver\Deriver\Evaluator\Execution\Memory\LiveArray;
52use Deriver\Deriver\Evaluator\Execution\Memory\Location;
53use Deriver\Deriver\Evaluator\Execution\Memory\Materialization;
54use Deriver\Deriver\Evaluator\Execution\Memory\Memory;
55use Deriver\Deriver\Evaluator\Execution\Memory\ReferenceConstraint;
56use Deriver\Deriver\Evaluator\Execution\Memory\Slots\SlotReference;
57use Deriver\Deriver\Evaluator\Execution\Memory\StorageCapture;
58use Deriver\Deriver\Evaluator\Execution\ObservationCollector;
59use Deriver\Deriver\Evaluator\Execution\Offset\Address;
60use Deriver\Deriver\Evaluator\Execution\Offset\Path;
61use Deriver\Deriver\Evaluator\Execution\Offset\Reader;
62use Deriver\Deriver\Evaluator\Execution\Offset\Transfer as OffsetTransfer;
63use Deriver\Deriver\Evaluator\Execution\Operation\Conversions;
64use Deriver\Deriver\Evaluator\Execution\Operation\ScalarErrors;
65use Deriver\Deriver\Evaluator\Execution\State;
66use Deriver\Deriver\Evaluator\Execution\Summary\CompletionRecord;
67use Deriver\Deriver\Evaluator\Execution\Summary\Evaluation;
68use Deriver\Deriver\Evaluator\Execution\Summary\Invocation;
69use Deriver\Deriver\Evaluator\Execution\Summary\Isolation;
70use Deriver\Deriver\Evaluator\Execution\Trace\Derivation;
71use Deriver\Deriver\Evaluator\Execution\Transfer\CompoundAssignment;
72use Deriver\Deriver\Evaluator\Execution\Transfer\MemoryStep;
73use Deriver\Deriver\Evaluator\Execution\Transfer\PureStep;
74use Deriver\Deriver\Evaluator\Execution\Transfer\ReferenceAssignment;
75use Deriver\Deriver\Evaluator\Request\Budget;
76use Deriver\Deriver\Evaluator\Request\EntryPoint;
77use Deriver\Deriver\Evaluator\Request\QueryScope;
78use Deriver\Deriver\Evaluator\Request\ReturnQuery;
79use Deriver\Deriver\Evaluator\Scalar\Arithmetic;
80use Deriver\Deriver\Evaluator\Scalar\Arrays;
81use Deriver\Deriver\Evaluator\Scalar\Identity;
82use Deriver\Deriver\Evaluator\Scalar\Operations;
83use Deriver\Deriver\Evaluator\TargetProfile;
84use Deriver\Deriver\Evaluator\Term;
85use Deriver\Deriver\Execution\DerivationResult;
86use Deriver\Deriver\Execution\QueryExecution;
87use Deriver\Deriver\Execution\ResultAssessment;
88use Deriver\Deriver\Identity\QueryEncoding;
89use Deriver\Deriver\Identity\ValueGraph;
90use Deriver\Deriver\Lowerer\AggregateLowering;
91use Deriver\Deriver\Lowerer\AssignmentLowering;
92use Deriver\Deriver\Lowerer\CallLowering;
93use Deriver\Deriver\Lowerer\Control\DestructuringLowering;
94use Deriver\Deriver\Lowerer\Control\LoopLowering;
95use Deriver\Deriver\Lowerer\Declaration\CallableIdentity;
96use Deriver\Deriver\Lowerer\Declaration\CallableSource;
97use Deriver\Deriver\Lowerer\Declaration\Index;
98use Deriver\Deriver\Lowerer\Declaration\Indexer;
99use Deriver\Deriver\Lowerer\Declaration\Traits\Composition;
100use Deriver\Deriver\Lowerer\ExpressionLowering;
101use Deriver\Deriver\Lowerer\Graph\BasicBlock;
102use Deriver\Deriver\Lowerer\Graph\CallableGraph;
103use Deriver\Deriver\Lowerer\Graph\Instruction;
104use Deriver\Deriver\Lowerer\Graph\Literal;
105use Deriver\Deriver\Lowerer\Graph\Terminator;
106use Deriver\Deriver\Lowerer\Hierarchy\Dispatch;
107use Deriver\Deriver\Lowerer\InstructionEmitter;
108use Deriver\Deriver\Lowerer\Lowerer;
109use Deriver\Deriver\Lowerer\LoweringScope;
110use Deriver\Deriver\Lowerer\StatementLowering;
111use Deriver\Deriver\MicroEvaluatorConversion;
112use Deriver\Deriver\Parser\Node\File;
113use Deriver\Deriver\Parser\Parser;
114use Deriver\Deriver\Parser\ParserConfig;
115use Deriver\Deriver\Parser\TargetSyntax;
116use Deriver\Deriver\Providers\ProviderExpansion;
117use Deriver\Deriver\Resolver\AssignmentPatterns;
118use Deriver\Deriver\Resolver\ClassScope;
119use Deriver\Deriver\Resolver\ExpressionValidation;
120use Deriver\Deriver\Resolver\MagicContext;
121use Deriver\Deriver\Resolver\Resolver;
122use Deriver\Deriver\Selection\QueryValidation;
123use Deriver\Deriver\SnapshotIdentity;
124use Deriver\Deriver\Sources\LineMap;
125use Deriver\Deriver\Sources\Path as SourcesPath;
126use Deriver\Deriver\Sources\Source;
127use Deriver\Deriver\Sources\SourceRef;
128use Deriver\Deriver\Sources\Sources;
129use Deriver\Exception\ParserException;
130use Deriver\Exception\ResolutionException;
131use JsonException;
132use PhpParser\Node\Expr\Variable;
133use PhpParser\Node\Scalar\Int_;
134use PhpParser\Node\Stmt\Continue_;
135use PhpParser\Node\Stmt\For_;
136use PhpParser\Node\Stmt\Foreach_;
137use PHPUnit\Framework\Attributes\CoversClass;
138use PHPUnit\Framework\Attributes\DataProvider;
139use PHPUnit\Framework\Attributes\Small;
140use PHPUnit\Framework\Attributes\UsesClass;
141use PHPUnit\Framework\TestCase;
142
143#[UsesClass(Resolver::class)]
144#[UsesClass(ExpressionValidation::class)]
145#[UsesClass(ResolutionException::class)]
146#[UsesClass(ParserConfig::class)]
147#[UsesClass(ParserException::class)]
148#[CoversClass(LoopLowering::class)]
149#[UsesClass(QueryExecution::class)]
150#[UsesClass(QueryValidation::class)]
151#[UsesClass(ResultAssessment::class)]
152#[UsesClass(Deriver::class)]
153#[UsesClass(Constraints::class)]
154#[UsesClass(BasicBlock::class)]
155#[UsesClass(CallableGraph::class)]
156#[UsesClass(CallableIdentity::class)]
157#[UsesClass(Instruction::class)]
158#[UsesClass(Terminator::class)]
159#[UsesClass(ArgumentBinding::class)]
160#[UsesClass(ArgumentOrder::class)]
161#[UsesClass(CallExecutor::class)]
162#[UsesClass(CallResolution::class)]
163#[UsesClass(CallableCheck::class)]
164#[UsesClass(Dispatch::class)]
165#[UsesClass(Resolution::class)]
166#[UsesClass(Target::class)]
167#[UsesClass(Transfer::class)]
168#[UsesClass(TypeBinding::class)]
169#[UsesClass(TypeCheck::class)]
170#[UsesClass(Completion::class)]
171#[UsesClass(Context::class)]
172#[UsesClass(IterationStep::class)]
173#[UsesClass(IteratorCursor::class)]
174#[UsesClass(LoopConvergence::class)]
175#[UsesClass(ObservationLimit::class)]
176#[UsesClass(StateJoin::class)]
177#[UsesClass(Unwinding::class)]
178#[UsesClass(Cell::class)]
179#[UsesClass(Components::class)]
180#[UsesClass(Discovery::class)]
181#[UsesClass(Key::class)]
182#[UsesClass(Table::class)]
183#[UsesClass(Dependencies::class)]
184#[UsesClass(InstructionTransfer::class)]
185#[UsesClass(Evaluator::class)]
186#[UsesClass(SlotReference::class)]
187#[UsesClass(ObservationCollector::class)]
188#[UsesClass(Address::class)]
189#[UsesClass(Path::class)]
190#[UsesClass(Reader::class)]
191#[UsesClass(OffsetTransfer::class)]
192#[UsesClass(Conversions::class)]
193#[UsesClass(ScalarErrors::class)]
194#[UsesClass(State::class)]
195#[UsesClass(CompletionRecord::class)]
196#[UsesClass(Evaluation::class)]
197#[UsesClass(Invocation::class)]
198#[UsesClass(Isolation::class)]
199#[UsesClass(CompoundAssignment::class)]
200#[UsesClass(MemoryStep::class)]
201#[UsesClass(PureStep::class)]
202#[UsesClass(ReferenceAssignment::class)]
203#[UsesClass(LiveArray::class)]
204#[UsesClass(Location::class)]
205#[UsesClass(Materialization::class)]
206#[UsesClass(Memory::class)]
207#[UsesClass(ReferenceConstraint::class)]
208#[UsesClass(StorageCapture::class)]
209#[UsesClass(Extensions::class)]
210#[UsesClass(ProviderExpansion::class)]
211#[UsesClass(Evaluators::class)]
212#[UsesClass(StateRegistry::class)]
213#[UsesClass(DeriverConfig::class)]
214#[UsesClass(EntryPoint::class)]
215#[UsesClass(Sources::class)]
216#[UsesClass(SourcesPath::class)]
217#[UsesClass(Snapshot::class)]
218#[UsesClass(Source::class)]
219#[UsesClass(TargetProfile::class)]
220#[UsesClass(Budget::class)]
221#[UsesClass(QueryScope::class)]
222#[UsesClass(ReturnQuery::class)]
223#[UsesClass(ResultRef::class)]
224#[UsesClass(SourceRef::class)]
225#[UsesClass(Alternative::class)]
226#[UsesClass(Assessment::class)]
227#[UsesClass(Derivation::class)]
228#[UsesClass(DerivationResult::class)]
229#[UsesClass(QueryEncoding::class)]
230#[UsesClass(ValueGraph::class)]
231#[UsesClass(Statistics::class)]
232#[UsesClass(StorageSnapshot::class)]
233#[UsesClass(Parser::class)]
234#[UsesClass(File::class)]
235#[UsesClass(AggregateLowering::class)]
236#[UsesClass(AssignmentLowering::class)]
237#[UsesClass(CallLowering::class)]
238#[UsesClass(Lowerer::class)]
239#[UsesClass(DestructuringLowering::class)]
240#[UsesClass(ExpressionLowering::class)]
241#[UsesClass(InstructionEmitter::class)]
242#[UsesClass(LoweringScope::class)]
243#[UsesClass(StatementLowering::class)]
244#[UsesClass(CallableSource::class)]
245#[UsesClass(Indexer::class)]
246#[UsesClass(Index::class)]
247#[UsesClass(Composition::class)]
248#[UsesClass(LineMap::class)]
249#[UsesClass(MagicContext::class)]
250#[UsesClass(AssignmentPatterns::class)]
251#[UsesClass(ClassScope::class)]
252#[UsesClass(TargetSyntax::class)]
253#[UsesClass(Arithmetic::class)]
254#[UsesClass(Arrays::class)]
255#[UsesClass(Identity::class)]
256#[UsesClass(Operations::class)]
257#[UsesClass(Literal::class)]
258#[Small]
259final class LoopLoweringTest extends TestCase
260{
261    public function testLowerPreservesTheSemanticContract(): void
262    {
263        $source = '<?php function target(){ $a=[1,2,3];foreach($a as &$x){}$x=4;unset($x);$x=5;return $a;}';
264        $symbol = 'target';
265        $input = new Sources([new Source('fixture.php', $source)]);
266        $configuration = new DeriverConfig();
267        $contributions = new Contributions();
268        $target = new TargetProfile($configuration->phpVersion, $configuration->integerBits, $configuration->floatPrecision);
269        $providers = new ProviderExpansion($input, array_map(Term::fromNative(...), $configuration->environment), $contributions);
270        $contributions1 = $providers->contributions;
271        $evaluators = new Evaluators(new TargetProfile($configuration->phpVersion, $configuration->integerBits, $configuration->floatPrecision), new Registrations($contributions1->evaluators, $contributions1->providers, $contributions1->domains, $contributions1->intrinsics, $contributions1->stateSlots), $configuration->standardEvaluators);
272        $settings = new EvaluatorConfig($target, $providers->environment, $configuration->standardEvaluators, array_map((new MicroEvaluatorConversion())->convert(...), $configuration->evaluators));
273        $identity = new SnapshotIdentity($providers->input, $settings, $evaluators, $providers->manifest);
274        $snapshotId = $identity->id;
275        $input1 = $providers->input;
276        $parser = new Parser(new ParserConfig($target->version));
277        $trees = array_map(static fn (Source $source1): File => (new Resolver())->resolve($parser->parse(new Source(SourcesPath::normalize($source1->path), $source1->contents, $source1->declarationsOnly))), iterator_to_array($input1, false));
278        $program = new Index($snapshotId, $trees);
279        $result = (new QueryExecution($program, new ExecutionEvaluatorConfig($target, $providers->environment, $configuration->standardEvaluators), $evaluators, $identity->snapshot(array_map(Frontier::fromDiagnostic(...), $program->diagnostics()))))->derive(new ReturnQuery($symbol));
280        self::assertSame([1, 2, 4], $result->normalOutcomes[0]->values['return']->native());
281        self::assertSame([], $result->frontiers);
282        self::assertSame([], $result->exceptionalOutcomes);
283    }
284    public function testInitializeTakesAnAddressForReferenceForeach(): void
285    {
286        $source = '<?php function target(){return 1;}';
287        $snapshotId = 'test';
288        $input = new Sources([new Source('fixture.php', $source)]);
289        $profile = new TargetProfile();
290        $parser = new Parser(new ParserConfig($profile->version));
291        $trees = array_map(static fn (Source $source1): File => (new Resolver())->resolve($parser->parse(new Source(SourcesPath::normalize($source1->path), $source1->contents, $source1->declarationsOnly))), iterator_to_array($input, false));
292        $index = new Index($snapshotId, $trees);
293        $l = new LoweringScope($index->builder('fixture.php'), $index, 'target');
294        $node = new Foreach_(new Variable('items'), new Variable('item'), ['byRef' => true]);
295        (new LoopLowering($l))->initialize($node);
296        self::assertSame(['local', 'iterator'], array_column($l->graph->instructions[0], 'operation'));
297        self::assertTrue($l->graph->instructions[0][1]->attributes['byReference']);
298    }
299    public function testConditionUsesTrueForAnOmittedForCondition(): void
300    {
301        $source = '<?php function target(){return 1;}';
302        $snapshotId = 'test';
303        $input = new Sources([new Source('fixture.php', $source)]);
304        $profile = new TargetProfile();
305        $parser = new Parser(new ParserConfig($profile->version));
306        $trees = array_map(static fn (Source $source1): File => (new Resolver())->resolve($parser->parse(new Source(SourcesPath::normalize($source1->path), $source1->contents, $source1->declarationsOnly))), iterator_to_array($input, false));
307        $index = new Index($snapshotId, $trees);
308        $l = new LoweringScope($index->builder('fixture.php'), $index, 'target');
309        (new LoopLowering($l))->condition(new For_(), '');
310        self::assertSame(true, $l->graph->instructions[0][0]->constant?->native());
311    }
312    public function testBindIterationAliasesTheActualElementForReferenceForeach(): void
313    {
314        $source = '<?php function target(){return 1;}';
315        $snapshotId = 'test';
316        $input = new Sources([new Source('fixture.php', $source)]);
317        $profile = new TargetProfile();
318        $parser = new Parser(new ParserConfig($profile->version));
319        $trees = array_map(static fn (Source $source1): File => (new Resolver())->resolve($parser->parse(new Source(SourcesPath::normalize($source1->path), $source1->contents, $source1->declarationsOnly))), iterator_to_array($input, false));
320        $index = new Index($snapshotId, $trees);
321        $l = new LoweringScope($index->builder('fixture.php'), $index, 'target');
322        $node = new Foreach_(new Variable('items'), new Variable('item'), ['byRef' => true]);
323        (new LoopLowering($l))->bindIteration($node, 'iterator');
324        self::assertSame(['iterator-address', 'local', 'alias'], array_column($l->graph->instructions[0], 'operation'));
325    }
326    public function testCompletionResolvesTheRequestedEnclosingLoopAndHandlerDepth(): void
327    {
328        $source = '<?php function target(){return 1;}';
329        $snapshotId = 'test';
330        $input = new Sources([new Source('fixture.php', $source)]);
331        $profile = new TargetProfile();
332        $parser = new Parser(new ParserConfig($profile->version));
333        $trees = array_map(static fn (Source $source1): File => (new Resolver())->resolve($parser->parse(new Source(SourcesPath::normalize($source1->path), $source1->contents, $source1->declarationsOnly))), iterator_to_array($input, false));
334        $index = new Index($snapshotId, $trees);
335        $l = new LoweringScope($index->builder('fixture.php'), $index, 'target');
336        $l->graph->loops = [['break' => 8, 'continue' => 7, 'depth' => 1], ['break' => 5, 'continue' => 4, 'depth' => 2]];
337        (new LoopLowering($l))->completion(new Continue_(new Int_(2)));
338        self::assertSame([7], $l->graph->terminators[0]->targets);
339        self::assertSame(1, $l->graph->terminators[0]->handlerDepth);
340    }
341    /**
342     * @throws JsonException If recorded observations cannot be decoded
343     */
344    #[DataProvider('providerForeachSemantics')]
345    public function testBindIterationPreservesRecordedPatternSemantics(string $source, string $normalJson, string $exception, bool $diagnostic): void
346    {
347        $expected = json_decode($normalJson, true, 512, JSON_THROW_ON_ERROR);
348        $symbol = 'target';
349        $input = new Sources([new Source('fixture.php', $source)]);
350        $configuration = new DeriverConfig();
351        $contributions = new Contributions();
352        $target = new TargetProfile($configuration->phpVersion, $configuration->integerBits, $configuration->floatPrecision);
353        $providers = new ProviderExpansion($input, array_map(Term::fromNative(...), $configuration->environment), $contributions);
354        $contributions1 = $providers->contributions;
355        $evaluators = new Evaluators(new TargetProfile($configuration->phpVersion, $configuration->integerBits, $configuration->floatPrecision), new Registrations($contributions1->evaluators, $contributions1->providers, $contributions1->domains, $contributions1->intrinsics, $contributions1->stateSlots), $configuration->standardEvaluators);
356        $settings = new EvaluatorConfig($target, $providers->environment, $configuration->standardEvaluators, array_map((new MicroEvaluatorConversion())->convert(...), $configuration->evaluators));
357        $identity = new SnapshotIdentity($providers->input, $settings, $evaluators, $providers->manifest);
358        $snapshotId = $identity->id;
359        $input1 = $providers->input;
360        $parser = new Parser(new ParserConfig($target->version));
361        $trees = array_map(static fn (Source $source1): File => (new Resolver())->resolve($parser->parse(new Source(SourcesPath::normalize($source1->path), $source1->contents, $source1->declarationsOnly))), iterator_to_array($input1, false));
362        $program = new Index($snapshotId, $trees);
363        $result = (new QueryExecution($program, new ExecutionEvaluatorConfig($target, $providers->environment, $configuration->standardEvaluators), $evaluators, $identity->snapshot(array_map(Frontier::fromDiagnostic(...), $program->diagnostics()))))->derive(new ReturnQuery($symbol));
364        self::assertSame($expected, array_map(static fn (Alternative $outcome) => $outcome->values['return']->native(), $result->normalOutcomes));
365        self::assertSame($exception === '' ? [] : [$exception], array_map(static fn (Exceptional $outcome): int|float|string|bool|null => $outcome->exception->literal, $result->exceptionalOutcomes));
366        self::assertSame($diagnostic, in_array('PHP_WARNING', array_column($result->frontiers, 'code'), true));
367        self::assertSame([], array_diff(array_column($result->frontiers, 'code'), ['PHP_WARNING']));
368    }
369    /**
370     * @return iterable<string,array{string,string,string,bool}>
371     */
372    public static function providerForeachSemantics(): iterable
373    {
374        foreach (['ArrayAccess values' => ['<?php class Box implements ArrayAccess{public array $data=[1,2];public array $log=[];function offsetGet(mixed $k):mixed{$this->log[]=$k;return $this->data[$k];}function offsetExists(mixed $k):bool{return true;}function offsetSet(mixed $k,mixed $v):void{$this->data[$k]=$v;}function offsetUnset(mixed $k):void{unset($this->data[$k]);}}function target(){$b=new Box;[$x,$y]=$b;return [$x,$y,$b->log];}', '[[1,2,[0,1]]]', '', false], 'ArrayAccess reference return' => ['<?php class Box implements ArrayAccess{public array $data=[1,2];function &offsetGet(mixed $k):mixed{return $this->data[$k];}function offsetExists(mixed $k):bool{return true;}function offsetSet(mixed $k,mixed $v):void{$this->data[$k]=$v;}function offsetUnset(mixed $k):void{unset($this->data[$k]);}}function target(){$b=new Box;[&$x,$y]=$b;$x=9;return [$b->data,$x,$y];}', '[[[9,2],9,2]]', '', false], 'ArrayAccess temporary reference notice' => ['<?php class Box implements ArrayAccess{public array $data=[1,2];function offsetGet(mixed $k):mixed{return $this->data[$k];}function offsetExists(mixed $k):bool{return true;}function offsetSet(mixed $k,mixed $v):void{$this->data[$k]=$v;}function offsetUnset(mixed $k):void{unset($this->data[$k]);}}function target(){$b=new Box;[&$x,$y]=$b;$x=9;return [$b->data,$x,$y];}', '[[[1,2],9,2]]', '', true], 'keys evaluate in entry order' => ['<?php function target(){$k=0;[$k=>$x,$k++=>$y]=[10,20];return [$k,$x,$y];}', '[[1,10,10]]', '', false], 'undefined source initialized by reference' => ['<?php function target(){[&$x]=$a;return [$a,$x];}', '[[[null],null]]', '', false], 'array reference' => ['<?php function target(){$a=[1,2];[&$x,$y]=$a;$x=7;return [$a,$x,$y];}', '[[[7,2],7,2]]', '', false], 'nested reference' => ['<?php function target(){$a=[[1,2]];[[&$x,$y]]=$a;$x=7;return [$a,$x,$y];}', '[[[[7,2]],7,2]]', '', false], 'missing reference' => ['<?php function target(){$a=[];[&$x]=$a;return [$a,$x];}', '[[[null],null]]', '', false], 'string values' => ['<?php function target(){[$x,$y]="ab";return [$x,$y];}', '[[null,null]]', '', false], 'integer values' => ['<?php function target(){[$x,$y]=4;return [$x,$y];}', '[[null,null]]', '', false], 'float values' => ['<?php function target(){[$x,$y]=4.5;return [$x,$y];}', '[[null,null]]', '', false], 'boolean values' => ['<?php function target(){[$x,$y]=true;return [$x,$y];}', '[[null,null]]', '', false], 'null values' => ['<?php function target(){[$x,$y]=null;return [$x,$y];}', '[[null,null]]', '', false], 'missing value warns' => ['<?php function target(){[$x,$y]=[1];return [$x,$y];}', '[[1,null]]', '', true], 'snapshot before overlapping value writes' => ['<?php function target(){$a=[1,2];[$a[1],$x]=$a;return [$a,$x];}', '[[[1,1],2]]', '', false], 'live source after overlapping reference binding' => ['<?php function target(){$a=[1,2];[&$a[1],$x]=$a;return [$a,$x];}', '[[[1,1],1]]', '', false], 'integer reference error' => ['<?php function target(){$a=4;try{[&$x]=$a;}catch(Throwable $e){return [get_class($e),$a];}return [$a,$x];}', '[["Error",4]]', '', false], 'null reference creates array' => ['<?php function target(){$a=null;[&$x]=$a;return [$a,$x];}', '[[[null],null]]', '', false], 'string reference error' => ['<?php function target(){$a="abc";try{[&$x]=$a;}catch(Throwable $e){return [get_class($e),$a];}return [$a,$x];}', '[["Error","abc"]]', '', false], 'ordinary function return reference notice' => ['<?php function make(){return [1];}function target(){[&$x]=make();$x=7;return $x;}', '[7]', '', true], 'foreach reference pattern' => ['<?php function target(){$a=[[1,2],[3,4]];foreach($a as [&$x,$y]){$x+=10;}$x=20;return [$a,$x,$y];}', '[[[[11,2],[20,4]],20,4]]', '', false], 'foreach temporary pattern' => ['<?php function target(){$sum=0;foreach([[1],[2]] as [&$x]){$sum+=$x;}$x=20;return [$sum,$x];}', '[[3,20]]', '', false], 'foreach value before key' => ['<?php function target(){$a=[[5]];foreach($a as $x=>[$x]){}return $x;}', '[0]', '', false], 'foreach reference before key' => ['<?php function target(){$a=[[5]];foreach($a as $x=>[&$x]){}return [$a,$x];}', '[[[[0]],0]]', '', false], 'foreach ordinary value before key' => ['<?php function target(){foreach([5] as $x=>$x){}return $x;}', '[0]', '', false], 'anchored source variable' => ['<?php function target(){$a=[1,2];[&$a,$x]=$a;return [$a,$x];}', '[[1,2]]', '', false], 'anchored nested source element' => ['<?php function target(){$a=[[1,2],9];[&$a[0],$x]=$a[0];return [$a,$x];}', '[[[1,9],2]]', '', false], 'assignment expression reference result' => ['<?php function target(){$a=[1,2];$b=([&$x,$y]=$a);$x=7;return [$a,$b,$x,$y];}', '[[[7,2],[7,2],7,2]]', '', false], 'assignment expression value result' => ['<?php function target(){$a=[1,2];$b=([$x,$y]=$a);$x=7;return [$a,$b,$x,$y];}', '[[[1,2],[1,2],7,2]]', '', false], 'holes keep numeric positions' => ['<?php function target(){list(,$x,,$y)=[1,2,3,4];return [$x,$y];}', '[[2,4]]', '', false], 'keyed dynamic pattern' => ['<?php function target(){$k="b";["a"=>$x,$k=>$y]=["b"=>2,"a"=>1];return [$x,$y];}', '[[1,2]]', '', false], 'nested keyed references' => ['<?php function target(){$a=["outer"=>["inner"=>1]];["outer"=>["inner"=>&$x]]=$a;$x=7;return [$a,$x];}', '[[{"outer":{"inner":7}},7]]', '', false], 'list syntax references' => ['<?php function target(){$a=[1,2];list(&$x,$y)=$a;$x=8;return [$a,$x,$y];}', '[[[8,2],8,2]]', '', false], 'declared reference return' => ['<?php function &source(&$a){return $a;}function target(){$a=[1];[&$x]=source($a);$x=8;return $a;}', '[[8]]', '', false], 'property source reference' => ['<?php class Box{public array $items=[1];}function target(){$b=new Box;[&$x]=$b->items;$x=9;return $b->items;}', '[[9]]', '', false], 'readonly source reference rejected' => ['<?php class Box{function __construct(public readonly array $items=[1]){}}function target(){$b=new Box;try{[&$x]=$b->items;}catch(Error $e){return $b->items;}return 999;}', '[[1]]', '', false], 'typed property destination coerces source' => ['<?php class Box{public int $x=0;}function target(){$a=["12"];$b=new Box;[&$b->x]=$a;return [$a,$b->x];}', '[[[12],12]]', '', false], 'typed property destination rejects reference' => ['<?php declare(strict_types=1);class Box{public int $x=0;}function target(){$a=["12"];$b=new Box;try{[&$b->x]=$a;}catch(TypeError $e){return [$a,$b->x];}return 999;}', '[[["12"],0]]', '', false], 'plain object destructuring error' => ['<?php class Box{}function target(){$b=new Box;try{[$x]=$b;}catch(Error $e){return 1;}return 999;}', '[1]', '', false], 'nested scalar destructuring' => ['<?php function target(){[[$x],[$y]]=["abc",null];return [$x,$y];}', '[[null,null]]', '', false], 'foreach temporary function result' => ['<?php function source(){return [[1],[2]];}function target(){$sum=0;foreach(source() as [&$x]){$sum+=$x;}$x=8;return [$sum,$x];}', '[[3,8]]', '', false], 'foreach ordinary reference temporary' => ['<?php function target(){foreach([1,2] as &$x){$x+=10;}return $x;}', '[12]', '', false]] as $name => $case) {
375            if (str_starts_with($name, 'foreach')) {
376                yield $name => $case;
377            }
378        }
379    }
380}
381