relax strict printf parameter check

Author: schlndh

src/Rules/Functions/PrintfPlaceholder.php

@@ -3,10 +3,14 @@
 namespace PHPStan\Rules\Functions;
 
 use PHPStan\ShouldNotHappenException;
+use PHPStan\Type\Accessory\AccessoryNumericStringType;
 use PHPStan\Type\ErrorType;
 use PHPStan\Type\FloatType;
 use PHPStan\Type\IntegerType;
+use PHPStan\Type\IntersectionType;
+use PHPStan\Type\NullType;
 use PHPStan\Type\StringAlwaysAcceptingObjectWithToStringType;
+use PHPStan\Type\StringType;
 use PHPStan\Type\Type;
 use PHPStan\Type\TypeCombinator;
 
@@ -34,7 +38,11 @@ public function doesArgumentTypeMatchPlaceholder(Type $argumentType, bool $stric
 					: ! $argumentType->toInteger() instanceof ErrorType;
 			case 'float':
 				return $strictPlaceholderTypes
-					? (new FloatType())->accepts($argumentType, true)->yes()
+					? TypeCombinator::union(
+						new FloatType(),
+						// numeric-string is allowed for consistency with phpstan-strict-rules.
+						new IntersectionType([new StringType(), new AccessoryNumericStringType()]),
+					)->accepts($argumentType, true)->yes()
 					: ! $argumentType->toFloat() instanceof ErrorType;
 			case 'string':
 			case 'mixed':
@@ -46,6 +54,8 @@ public function doesArgumentTypeMatchPlaceholder(Type $argumentType, bool $stric
 						new StringAlwaysAcceptingObjectWithToStringType(),
 						// float also accepts int.
 						new FloatType(),
+						// null is allowed for consistency with phpstan-strict-rules (e.g. $string . $null).
+						new NullType(),
 					)->accepts($argumentType, true)->yes();
 			// Without this PHPStan with PHP 7.4 reports "...should return bool but return statement is missing."
 			// Presumably, because promoted properties are turned into regular properties and the phpdoc isn't applied to the property.

tests/PHPStan/Rules/Functions/PrintfParameterTypeRuleTest.php

@@ -222,10 +222,6 @@ public function testStrict(): void
 				'Parameter #2 of function printf is expected to be int by placeholder #1 ("%d"), SimpleXMLElement given.',
 				40,
 			],
-			[
-				'Parameter #2 of function printf is expected to be float by placeholder #1 ("%f"), string given.',
-				42,
-			],
 			[
 				'Parameter #2 of function printf is expected to be float by placeholder #1 ("%f"), null given.',
 				43,
@@ -238,10 +234,6 @@ public function testStrict(): void
 				'Parameter #2 of function printf is expected to be float by placeholder #1 ("%f"), SimpleXMLElement given.',
 				45,
 			],
-			[
-				'Parameter #2 of function printf is expected to be string by placeholder #1 ("%s"), null given.',
-				47,
-			],
 			[
 				'Parameter #2 of function printf is expected to be string by placeholder #1 ("%s"), true given.',
 				48,

tests/PHPStan/Rules/Functions/data/printf-param-types.php

@@ -39,12 +39,12 @@ public function __toString(): string
 printf('%d', true);
 printf('%d', new \SimpleXMLElement('<a>aaa</a>'));
 
-printf('%f', '1.2345678901234567890123456789013245678901234567989');
+
 printf('%f', null);
 printf('%f', true);
 printf('%f', new \SimpleXMLElement('<a>aaa</a>'));
 
-printf('%s', null);
+
 printf('%s', true);
 
 // Error, but already reported by CallToFunctionParametersRule
@@ -55,6 +55,10 @@ public function __toString(): string
 printf('%s');
 printf('%s', 1, 2);
 
+// Arguable
+printf('%f', '1.2345678901234567890123456789013245678901234567989');
+printf('%s', null);
+
 // OK
 printf('%s', 'a');
 printf('%s', new FooStringable());