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Merged
merged 7 commits into from
Nov 6, 2024
Merged

Support for endless loops #3573

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16d0d80
Support `for` endless loops
herndlm Oct 14, 2024
19296c5
Revert unnecessary change
herndlm Oct 14, 2024
ad2f7d1
Use isAlwaysTerminating of finalScopeResult and update test
herndlm Oct 15, 2024
7fa7239
Update e2e baseline
herndlm Oct 15, 2024
dbbb3f8
Add 2 more regression tests
herndlm Oct 15, 2024
367cf00
Add moar tests
herndlm Oct 15, 2024
6779b98
Try to support all the for end loop scenarios :)
herndlm Nov 6, 2024
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13 changes: 12 additions & 1 deletion src/Analyser/NodeScopeResolver.php
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Original file line number Diff line number Diff line change
Expand Up @@ -1384,7 +1384,10 @@ private function processStmtNode(
$loopScope = $this->processExprNode($stmt, $loopExpr, $loopScope, $nodeCallback, ExpressionContext::createTopLevel())->getScope();
}
$finalScope = $finalScope->generalizeWith($loopScope);

$alwaysIterates = TrinaryLogic::createFromBoolean($context->isTopLevel());
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Would something fail if you said $alwaysIterates = TrinaryLogic::createYes() here?

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@herndlm herndlm Nov 6, 2024 •
edited
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no, apparently not. this comes basically from the other loops which have code like the following

$alwaysIterates = $condBooleanType->isTrue()->yes() && $context->isTopLevel();

but tbh, I didn't fully understand what the level here changes or does

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OK, makes sense to be consistent.

This condition asks about whether it's the "analysis iteration", or one of the "let's find out if types stabilize in the loop before we generalize them" that's done for all loops in a do-while like this:

phpstan-src/src/Analyser/NodeScopeResolver.php

Lines 1330 to 1360 in c3bb055

do {
$prevScope = $bodyScope;
$bodyScope = $bodyScope->mergeWith($initScope);
if ($lastCondExpr !== null) {
$bodyScope = $this->processExprNode($stmt, $lastCondExpr, $bodyScope, static function (): void {
}, ExpressionContext::createDeep())->getTruthyScope();
}
$bodyScopeResult = $this->processStmtNodes($stmt, $stmt->stmts, $bodyScope, static function (): void {
}, $context->enterDeep())->filterOutLoopExitPoints();
$bodyScope = $bodyScopeResult->getScope();
foreach ($bodyScopeResult->getExitPointsByType(Continue_::class) as $continueExitPoint) {
$bodyScope = $bodyScope->mergeWith($continueExitPoint->getScope());
}
foreach ($stmt->loop as $loopExpr) {
$exprResult = $this->processExprNode($stmt, $loopExpr, $bodyScope, static function (): void {
}, ExpressionContext::createTopLevel());
$bodyScope = $exprResult->getScope();
$hasYield = $hasYield || $exprResult->hasYield();
$throwPoints = array_merge($throwPoints, $exprResult->getThrowPoints());
$impurePoints = array_merge($impurePoints, $exprResult->getImpurePoints());
}
if ($bodyScope->equals($prevScope)) {
break;
}
if ($count >= self::GENERALIZE_AFTER_ITERATION) {
$bodyScope = $prevScope->generalizeWith($bodyScope);
}
$count++;
} while ($count < self::LOOP_SCOPE_ITERATIONS);

if ($lastCondExpr !== null) {
$alwaysIterates = $alwaysIterates->and($finalScope->getType($lastCondExpr)->toBoolean()->isTrue());
$finalScope = $finalScope->filterByFalseyValue($lastCondExpr);
}

Expand All @@ -1411,10 +1414,18 @@ private function processStmtNode(
}
}

if ($alwaysIterates->yes()) {
$isAlwaysTerminating = count($finalScopeResult->getExitPointsByType(Break_::class)) === 0;
} elseif ($isIterableAtLeastOnce->yes()) {
$isAlwaysTerminating = $finalScopeResult->isAlwaysTerminating();
} else {
$isAlwaysTerminating = false;
}

return new StatementResult(
$finalScope,
$finalScopeResult->hasYield() || $hasYield,
false/* $finalScopeResult->isAlwaysTerminating() && $isAlwaysIterable*/,
$isAlwaysTerminating,
$finalScopeResult->getExitPointsForOuterLoop(),
array_merge($throwPoints, $finalScopeResult->getThrowPoints()),
array_merge($impurePoints, $finalScopeResult->getImpurePoints()),
Expand Down
126 changes: 125 additions & 1 deletion tests/PHPStan/Analyser/StatementResultTest.php
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Expand Up @@ -173,6 +173,130 @@ public function dataIsAlwaysTerminating(): array
'while (true) { break; }',
false,
],
[
'while (true) { exit; }',
true,
],
[
'while (true) { while (true) { } }',
true,
],
[
'while (true) { while (true) { return; } }',
true,
],
[
'while (true) { while (true) { break; } }',
true,
],
[
'while (true) { while (true) { exit; } }',
true,
],
[
'while (true) { while (true) { break 2; } }',
false,
],
[
'while (true) { while ($x) { } }',
true,
],
[
'while (true) { while ($x) { return; } }',
true,
],
[
'while (true) { while ($x) { break; } }',
true,
],
[
'while (true) { while ($x) { exit; } }',
true,
],
[
'while (true) { while ($x) { break 2; } }',
false,
],
[
'for (;;) { }',
true,
],
[
'for (;;) { return; }',
true,
],
[
'for (;;) { break; }',
false,
],
[
'for (;;) { exit; }',
true,
],
[
'for (;;) { for (;;) { } }',
true,
],
[
'for (;;) { for (;;) { return; } }',
true,
],
[
'for (;;) { for (;;) { break; } }',
true,
],
[
'for (;;) { for (;;) { exit; } }',
true,
],
[
'for (;;) { for (;;) { break 2; } }',
false,
],
[
'for (;;) { for ($i = 0; $i< 5; $i++) { } }',
true,
],
[
'for (;;) { for ($i = 0; $i< 5; $i++) { return; } }',
true,
],
[
'for (;;) { for ($i = 0; $i< 5; $i++) { break; } }',
true,
],
[
'for (;;) { for ($i = 0; $i< 5; $i++) { exit; } }',
true,
],
[
'for (;;) { for ($i = 0; $i< 5; $i++) { break 2; } }',
false,
],
[
'for ($i = 0; $i < 5;) { }',
true,
],
[
'for ($i = 0; $i < 5; $i--) { }',
true,
],
[
'for (; 0, 1;) { }',
true,
],
[
'for (; 1, 0;) { }',
false,
],
[
'for (; "", "a";) { }',
true,
],
[
'for (; "a", "";) { }',
false,
],
[
'do { } while (doFoo());',
false,
Expand Down Expand Up @@ -231,7 +355,7 @@ public function dataIsAlwaysTerminating(): array
],
[
'for ($i = 0; $i < 10; $i++) { return; }',
false, // will be true with range types
true,
],
[
'for ($i = 0; $i < 0; $i++) { return; }',
Expand Down
10 changes: 5 additions & 5 deletions tests/PHPStan/Rules/Comparison/StrictComparisonOfDifferentTypesRuleTest.php
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Expand Up @@ -109,12 +109,12 @@ public function testStrictComparison(): void
140,
],
[
'Strict comparison using !== between StrictComparison\Foo|null and 1 will always evaluate to true.',
154,
'Strict comparison using === between non-empty-array and null will always evaluate to false.',
150,
],
[
'Strict comparison using === between non-empty-array and null will always evaluate to false.',
164,
'Strict comparison using !== between StrictComparison\Foo|null and 1 will always evaluate to true.',
161,
],
[
'Strict comparison using !== between StrictComparison\Node|null and false will always evaluate to true.',
Expand Down Expand Up @@ -352,7 +352,7 @@ public function testStrictComparisonWithoutAlwaysTrue(): void
],
[
'Strict comparison using === between non-empty-array and null will always evaluate to false.',
164,
150,
],
[
'Strict comparison using === between 1 and 2 will always evaluate to false.',
Expand Down
14 changes: 7 additions & 7 deletions tests/PHPStan/Rules/Comparison/data/strict-comparison.php
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Expand Up @@ -146,6 +146,13 @@ public function whileWithTypeChange()

public function forWithTypeChange()
{
for (; $val = $this->returnArray();) {
if ($val === null) {

}
$val = null;
}

$foo = null;
for (;;) {
if ($foo !== null) {
Expand All @@ -159,13 +166,6 @@ public function forWithTypeChange()
$foo = new self();
}
}

for (; $val = $this->returnArray();) {
if ($val === null) {

}
$val = null;
}
}

private function returnArray(): array
Expand Down
18 changes: 18 additions & 0 deletions tests/PHPStan/Rules/Missing/MissingReturnRuleTest.php
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Expand Up @@ -325,4 +325,22 @@ public function testBug9309(): void
$this->analyse([__DIR__ . '/data/bug-9309.php'], []);
}

public function testBug6807(): void
{
$this->checkExplicitMixedMissingReturn = true;
$this->analyse([__DIR__ . '/data/bug-6807.php'], []);
}

public function testBug8463(): void
{
$this->checkExplicitMixedMissingReturn = true;
$this->analyse([__DIR__ . '/data/bug-8463.php'], []);
}

public function testBug9374(): void
{
$this->checkExplicitMixedMissingReturn = true;
$this->analyse([__DIR__ . '/data/bug-9374.php'], []);
}

}
16 changes: 16 additions & 0 deletions tests/PHPStan/Rules/Missing/data/bug-6807.php
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@@ -0,0 +1,16 @@
<?php declare(strict_types = 1);

namespace Bug6807;

/** @return int */
function test()
{
for ($attempts = 0; ; $attempts++)
{
if ($attempts > 5)
throw new Exception();

if (rand() == 1)
return 5;
}
}
26 changes: 26 additions & 0 deletions tests/PHPStan/Rules/Missing/data/bug-8463.php
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@@ -0,0 +1,26 @@
<?php

namespace Bug8463;

function f1() : int
{
while(true)
{
if(rand() === rand())
{
return 1;
}
}
}


function f2() : int
{
for(;;)
{
if(rand() === rand())
{
return 1;
}
}
}
8 changes: 8 additions & 0 deletions tests/PHPStan/Rules/Missing/data/bug-9374.php
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@@ -0,0 +1,8 @@
<?php declare(strict_types = 1);

namespace Bug9374;

function bar(): string {
for ($i = 0; ; ++$i)
return "";
}
2 changes: 1 addition & 1 deletion tests/PHPStan/Rules/Variables/data/defined-variables-anonymous-function-use.php
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Expand Up @@ -14,7 +14,7 @@ function () use (&$errorHandler) {
$onlyInIf = 1;
}

for ($forI = 0; $forI < 10, $anotherVariableFromForCond = 1; $forI++, $forJ = $forI) {
for ($forI = 0; $anotherVariableFromForCond = 1, $forI < 10; $forI++, $forJ = $forI) {

}

Expand Down
6 changes: 3 additions & 3 deletions tests/PHPStan/Rules/Variables/data/defined-variables.php
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Expand Up @@ -243,7 +243,7 @@ function () {

}

for ($forI = 0; $forI < 10, $forK = 5; $forI++, $forK++, $forJ = $forI) {
for ($forI = 0; $forK = 5, $forI < 10; $forI++, $forK++, $forJ = $forI) {
echo $forI;
}

Expand Down Expand Up @@ -322,7 +322,7 @@ function () {
include($fileB='includeB.php');
echo $fileB;

for ($forLoopVariableInit = 0; $forLoopVariableInit < 5; $forLoopVariableInit = $forLoopVariable, $anotherForLoopVariable = 1) {
for ($forLoopVariableInit = 0; $forLoopVariableInit < 5 && rand(0, 1); $forLoopVariableInit = $forLoopVariable, $anotherForLoopVariable = 1) {
$forLoopVariable = 2;
}
echo $anotherForLoopVariable;
Expand Down Expand Up @@ -357,7 +357,7 @@ function () {

}

for (; $forVariableUsedAndThenDefined && $forVariableUsedAndThenDefined = 1;) {
for (; $forVariableUsedAndThenDefined && $forVariableUsedAndThenDefined = 1 && rand(0, 1);) {

}

Expand Down
5 changes: 5 additions & 0 deletions tests/e2e/baseline.neon
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Expand Up @@ -155,6 +155,11 @@ parameters:
count: 1
path: PHP-Parser/lib/PhpParser/ParserAbstract.php

-
message: "#^Unreachable statement \\- code above always terminates\\.$#"
count: 1
path: PHP-Parser/lib/PhpParser/ParserAbstract.php

-
message: "#^Variable \\$action might not be defined\\.$#"
count: 1
Expand Down
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