vprintf/vsprintf require a non-empty-array argument

conf/bleedingEdge.neon

@@ -56,5 +56,6 @@ parameters:
 		checkParameterCastableToStringFunctions: true
 		narrowPregMatches: true
 		uselessReturnValue: true
+		printfArrayParameters: true
 	stubFiles:
 		- ../stubs/bleedingEdge/Rule.stub

conf/config.level0.neon

@@ -26,6 +26,8 @@ conditionalTags:
 		phpstan.rules.rule: %featureToggles.magicConstantOutOfContext%
 	PHPStan\Rules\Functions\UselessFunctionReturnValueRule:
 		phpstan.rules.rule: %featureToggles.uselessReturnValue%
+	PHPStan\Rules\Functions\PrintfArrayParametersRule:
+		phpstan.rules.rule: %featureToggles.printfArrayParameters%
 
 rules:
 	- PHPStan\Rules\Api\ApiInstantiationRule
@@ -298,3 +300,6 @@ services:
 
 	-
 		class: PHPStan\Rules\Functions\UselessFunctionReturnValueRule
+
+	-
+		class: PHPStan\Rules\Functions\PrintfArrayParametersRule

conf/config.neon

@@ -91,6 +91,7 @@ parameters:
 		checkParameterCastableToStringFunctions: false
 		narrowPregMatches: false
 		uselessReturnValue: false
+		printfArrayParameters: false
 	fileExtensions:
 		- php
 	checkAdvancedIsset: false

conf/parametersSchema.neon

@@ -86,6 +86,7 @@ parametersSchema:
 		checkParameterCastableToStringFunctions: bool()
 		narrowPregMatches: bool()
 		uselessReturnValue: bool()
+		printfArrayParameters: bool()
 	])
 	fileExtensions: listOf(string())
 	checkAdvancedIsset: bool()

src/Rules/Functions/PrintfArrayParametersRule.php

@@ -0,0 +1,188 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Rules\Functions;
+
+use PhpParser\Node;
+use PhpParser\Node\Expr\FuncCall;
+use PHPStan\Analyser\Scope;
+use PHPStan\Reflection\ReflectionProvider;
+use PHPStan\Rules\Rule;
+use PHPStan\Rules\RuleErrorBuilder;
+use PHPStan\ShouldNotHappenException;
+use PHPStan\Type\Constant\ConstantIntegerType;
+use PHPStan\Type\IntegerRangeType;
+use PHPStan\Type\TypeCombinator;
+use function count;
+use function in_array;
+use function max;
+use function min;
+use function sprintf;
+
+/**
+ * @implements Rule<Node\Expr\FuncCall>
+ */
+class PrintfArrayParametersRule implements Rule
+{
+
+	public function __construct(
+		private PrintfHelper $printfHelper,
+		private ReflectionProvider $reflectionProvider,
+	)
+	{
+	}
+
+	public function getNodeType(): string
+	{
+		return FuncCall::class;
+	}
+
+	public function processNode(Node $node, Scope $scope): array
+	{
+		if (!($node->name instanceof Node\Name)) {
+			return [];
+		}
+
+		if (!$this->reflectionProvider->hasFunction($node->name, $scope)) {
+			return [];
+		}
+
+		$functionReflection = $this->reflectionProvider->getFunction($node->name, $scope);
+		$name = $functionReflection->getName();
+		if (!in_array($name, ['vprintf', 'vsprintf'], true)) {
+			return [];
+		}
+
+		$args = $node->getArgs();
+		$argsCount = count($args);
+		if ($argsCount < 1) {
+			return []; // caught by CallToFunctionParametersRule
+		}
+
+		$formatArgType = $scope->getType($args[0]->value);
+		$placeHoldersCounts = [];
+		foreach ($formatArgType->getConstantStrings() as $formatString) {
+			$format = $formatString->getValue();
+
+			$placeHoldersCounts[] = $this->printfHelper->getPrintfPlaceholdersCount($format);
+		}
+
+		if ($placeHoldersCounts === []) {
+			return [];
+		}
+
+		$minCount = min($placeHoldersCounts);
+		$maxCount = max($placeHoldersCounts);
+		if ($minCount === $maxCount) {
+			$placeHoldersCount = new ConstantIntegerType($minCount);
+		} else {
+			$placeHoldersCount = IntegerRangeType::fromInterval($minCount, $maxCount);
+
+			if (!$placeHoldersCount instanceof IntegerRangeType && !$placeHoldersCount instanceof ConstantIntegerType) {
+				return [];
+			}
+		}
+
+		$formatArgsCounts = [];
+		if (isset($args[1])) {
+			$formatArgsType = $scope->getType($args[1]->value);
+
+			$constantArrays = $formatArgsType->getConstantArrays();
+			foreach ($constantArrays as $constantArray) {
+				$formatArgsCounts[] = $constantArray->getArraySize();
+			}
+
+			if ($constantArrays === []) {
+				$formatArgsCounts[] = $formatArgsType->getArraySize();
+			}
+		}
+
+		if ($formatArgsCounts === []) {
+			$formatArgsCount = new ConstantIntegerType(0);
+		} else {
+			$formatArgsCount = TypeCombinator::union(...$formatArgsCounts);
+
+			if (!$formatArgsCount instanceof IntegerRangeType && !$formatArgsCount instanceof ConstantIntegerType) {
+				return [];
+			}
+		}
+
+		if (!$this->placeholdersMatchesArgsCount($placeHoldersCount, $formatArgsCount)) {
+
+			if ($placeHoldersCount instanceof IntegerRangeType) {
+				$placeholders = $this->getIntegerRangeAsString($placeHoldersCount);
+				$singlePlaceholder = false;
+			} else {
+				$placeholders = $placeHoldersCount->getValue();
+				$singlePlaceholder = $placeholders === 1;
+			}
+
+			if ($formatArgsCount instanceof IntegerRangeType) {
+				$values = $this->getIntegerRangeAsString($formatArgsCount);
+				$singleValue = false;
+			} else {
+				$values = $formatArgsCount->getValue();
+				$singleValue = $values === 1;
+			}
+
+			return [
+				RuleErrorBuilder::message(sprintf(
+					sprintf(
+						'%s, %s.',
+						$singlePlaceholder ? 'Call to %s contains %d placeholder' : 'Call to %s contains %s placeholders',
+						$singleValue ? '%d value given' : '%s values given',
+					),
+					$name,
+					$placeholders,
+					$values,
+				))->identifier(sprintf('argument.%s', $name))->build(),
+			];
+		}
+
+		return [];
+	}
+
+	private function placeholdersMatchesArgsCount(ConstantIntegerType|IntegerRangeType $placeHoldersCount, ConstantIntegerType|IntegerRangeType $formatArgsCount): bool
+	{
+		if ($placeHoldersCount instanceof ConstantIntegerType) {
+			if ($formatArgsCount instanceof ConstantIntegerType) {
+				return $placeHoldersCount->getValue() === $formatArgsCount->getValue();
+			}
+
+			// Zero placeholders + array
+			if ($placeHoldersCount->getValue() === 0) {
+				return true;
+			}
+
+			return false;
+		}
+
+		if (
+			$formatArgsCount instanceof IntegerRangeType
+			&& IntegerRangeType::fromInterval(1, null)->isSuperTypeOf($placeHoldersCount)->yes()
+		) {
+			if ($formatArgsCount->getMin() !== null && $formatArgsCount->getMax() !== null) {
+				// constant array
+				return $placeHoldersCount->isSuperTypeOf($formatArgsCount)->yes();
+			}
+
+			// general array
+			return IntegerRangeType::fromInterval(1, null)->isSuperTypeOf($formatArgsCount)->yes();
+		}
+
+		return false;
+	}
+
+	private function getIntegerRangeAsString(IntegerRangeType $range): string
+	{
+		if ($range->getMin() !== null && $range->getMax() !== null) {
+			return $range->getMin() . '-' . $range->getMax();
+		} elseif ($range->getMin() !== null) {
+			return $range->getMin() . ' or more';
+		} elseif ($range->getMax() !== null) {
+			return $range->getMax() . ' or less';
+		}
+
+		throw new ShouldNotHappenException();
+	}
+
+}

tests/PHPStan/Rules/Functions/PrintfArrayParametersRuleTest.php

@@ -0,0 +1,78 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Rules\Functions;
+
+use PHPStan\Php\PhpVersion;
+use PHPStan\Rules\Rule;
+use PHPStan\Testing\RuleTestCase;
+use const PHP_VERSION_ID;
+
+/**
+ * @extends RuleTestCase<PrintfArrayParametersRule>
+ */
+class PrintfArrayParametersRuleTest extends RuleTestCase
+{
+
+	protected function getRule(): Rule
+	{
+		return new PrintfArrayParametersRule(
+			new PrintfHelper(new PhpVersion(PHP_VERSION_ID)),
+			$this->createReflectionProvider(),
+		);
+	}
+
+	public function testFile(): void
+	{
+		$this->analyse([__DIR__ . '/data/vprintf.php'], [
+			[
+				'Call to vsprintf contains 2 placeholders, 1 value given.',
+				10,
+			],
+			[
+				'Call to vsprintf contains 0 placeholders, 1 value given.',
+				11,
+			],
+			[
+				'Call to vsprintf contains 1 placeholder, 2 values given.',
+				12,
+			],
+			[
+				'Call to vsprintf contains 2 placeholders, 1 value given.',
+				13,
+			],
+			[
+				'Call to vsprintf contains 2 placeholders, 0 values given.',
+				14,
+			],
+			[
+				'Call to vsprintf contains 2 placeholders, 0 values given.',
+				15,
+			],
+			[
+				'Call to vsprintf contains 4 placeholders, 0 values given.',
+				16,
+			],
+			[
+				'Call to vsprintf contains 5 placeholders, 2 values given.',
+				18,
+			],
+			[
+				'Call to vsprintf contains 1 placeholder, 2 values given.',
+				21,
+			],
+			[
+				'Call to vsprintf contains 1 placeholder, 1-2 values given.',
+				29,
+			],
+			[
+				'Call to vprintf contains 2 placeholders, 1 value given.',
+				34,
+			],
+			[
+				'Call to vsprintf contains 1-2 placeholders, 0 or more values given.',
+				53,
+			],
+		]);
+	}
+
+}

tests/PHPStan/Rules/Functions/data/vprintf.php

@@ -0,0 +1,64 @@
+<?php
+
+namespace PrintfArrayParametersRuleTest;
+
+function doFoo($message, array $arr) {
+	vsprintf($message, 'foo'); // skip - format not a literal string
+
+	vsprintf('%s', ['foo']); // ok
+	vsprintf('%s %% %% %s', ['foo', 'bar']); // ok
+	vsprintf('%s %s', ['foo']); // one parameter missing
+	vsprintf('foo', ['foo']); // one parameter over
+	vsprintf('foo %s', ['foo', 'bar']); // one parameter over
+	vsprintf('%2$s %1$s %% %1$s %%%', ['one']); // one parameter missing
+	vsprintf('%2$s %%'); // two parameters required
+	vsprintf('%2$s %%', []); // two parameters required
+	vsprintf('%2$s %1$s %1$s %s %s %s %s'); // four parameters required
+	vsprintf('%2$s %1$s %% %s %s %s %s %%% %%%%', ['one', 'two', 'three', 'four']); // ok
+	vsprintf("%'.9d %1$'.9d %0.3f %d %d %d", [123, 456]); // five parameters required
+
+	vsprintf('%-4s', ['foo']); // ok
+	vsprintf('%%s %s', ['foo', 'bar']); // one parameter over
+
+
+	if (rand(0,1)) {
+		$args = ['foo'];
+	} else {
+		$args = ['foo', 'bar'];
+	}
+	vsprintf('%-4s', $args); // one path with wrong number of args
+
+
+	vprintf('%s', ['foo']); // ok
+	vprintf('%s %% %% %s', ['foo', 'bar']); // ok
+	vprintf('%s %s', ['foo']); // one parameter missing
+	vprintf('abc'); // caught by CallToFunctionParametersRule
+	vsprintf('abc', []); // ok
+	vsprintf('abc', $arr); // ok
+
+	if (rand(0,1)) {
+		$format = '%s';
+		$args = ['foo'];
+	} else {
+		$format = '%s%s';
+		$args = ['foo', 'bar'];
+	}
+	vsprintf($format, $args); // ok
+
+	if (rand(0,1)) {
+		$format = '%s';
+	} else {
+		$format = '%s%s';
+	}
+	vsprintf($format, $arr); // need at least non-empty-array
+
+	if (rand(0,1)) {
+		$format = '%s';
+	} else {
+		$format = '%s%s';
+	}
+	if ($arr !== []) {
+		vsprintf($format, $arr); // ok
+	}
+
+}