Fix sprintf dynamic return type

Author: VincentLanglet

Diff for: src/Type/Php/SprintfFunctionDynamicReturnTypeExtension.php

@@ -29,6 +29,7 @@
 use function count;
 use function in_array;
 use function intval;
+use function is_array;
 use function is_string;
 use function preg_match;
 use function sprintf;
@@ -69,7 +70,7 @@ public function getTypeFromFunctionCall(
 			static fn (Type $type): bool => $type->toString()->isLowercaseString()->yes()
 		);
 
-		$singlePlaceholderEarlyReturn = null;
+		$singlePlaceholderEarlyReturn = [];
 		$allPatternsNonEmpty = count($formatStrings) !== 0;
 		$allPatternsNonFalsy = count($formatStrings) !== 0;
 		foreach ($formatStrings as $constantString) {
@@ -93,8 +94,11 @@ public function getTypeFromFunctionCall(
 				$allPatternsNonFalsy = false;
 			}
 
-			// The printf format is %[argnum$][flags][width][.precision]specifier.
-			if (preg_match('/^%(?P<argnum>[0-9]*\$)?(?P<width>[0-9]*)\.?[0-9]*(?P<specifier>[sbdeEfFgGhHouxX])$/', $constantString->getValue(), $matches) === 1) {
+			if (
+				is_array($singlePlaceholderEarlyReturn)
+				// The printf format is %[argnum$][flags][width][.precision]specifier.
+				&& preg_match('/^%(?P<argnum>[0-9]*\$)?(?P<width>[0-9]*)\.?[0-9]*(?P<specifier>[sbdeEfFgGhHouxX])$/', $constantString->getValue(), $matches) === 1
+			) {
 				if ($matches['argnum'] !== '') {
 					// invalid positional argument
 					if ($matches['argnum'] === '0$') {
@@ -122,24 +126,22 @@ public function getTypeFromFunctionCall(
 						$constArgTypes = $checkArgType->getConstantScalarTypes();
 					}
 					if ($constArgTypes !== []) {
-						$result = [];
 						$printfArgs = array_fill(0, count($args) - 1, '');
 						foreach ($constArgTypes as $constArgType) {
 							$printfArgs[$checkArg - 1] = $constArgType->getValue();
 							try {
-								$result[] = new ConstantStringType(@sprintf($constantString->getValue(), ...$printfArgs));
+								$singlePlaceholderEarlyReturn[] = new ConstantStringType(@sprintf($constantString->getValue(), ...$printfArgs));
 							} catch (Throwable) {
 								continue 2;
 							}
 						}
-						$singlePlaceholderEarlyReturn = TypeCombinator::union(...$result);
 
 						continue;
 					}
 
-					$singlePlaceholderEarlyReturn = $checkArgType->toString();
+					$singlePlaceholderEarlyReturn[] = $checkArgType->toString();
 				} elseif ($matches['specifier'] !== 's') {
-					$singlePlaceholderEarlyReturn = $this->getStringReturnType(
+					$singlePlaceholderEarlyReturn[] = $this->getStringReturnType(
 						new AccessoryNumericStringType(),
 						$isLowercase,
 					);
@@ -149,11 +151,10 @@ public function getTypeFromFunctionCall(
 			}
 
 			$singlePlaceholderEarlyReturn = null;
-			break;
 		}
 
-		if ($singlePlaceholderEarlyReturn !== null) {
-			return $singlePlaceholderEarlyReturn;
+		if (is_array($singlePlaceholderEarlyReturn) && count($singlePlaceholderEarlyReturn) > 0) {
+			return TypeCombinator::union(...$singlePlaceholderEarlyReturn);
 		}
 
 		if ($allPatternsNonFalsy) {

Diff for: tests/PHPStan/Analyser/nsrt/bug-12065.php

@@ -0,0 +1,43 @@
+<?php declare(strict_types=1);
+
+namespace Bug12065;
+
+use function PHPStan\Testing\assertType;
+
+final class Foo
+{
+	public function bar(
+		string $key,
+		bool $preserveKeys,
+		bool $flatten = true,
+	): void {
+		$format = $preserveKeys ? '[%s]' : '';
+
+		if ($flatten) {
+			$_key = sprintf($format, $key);
+		} else {
+			$_key = sprintf($format, $key);
+			assertType('string', $_key);
+			// @phpstan-ignore identical.alwaysFalse
+			if ($_key === '') {
+				// ...
+			}
+		}
+	}
+
+	/**
+	 * @param int<1,2> $key
+	 * @param bool     $preserveKeys
+	 *
+	 * @return void
+	 */
+	public function bar2(
+		string $key,
+		bool $preserveKeys,
+	): void {
+		$format = $preserveKeys ? '%s' : '%d';
+
+		$_key = sprintf($format, $key);
+		assertType("string", $_key);
+	}
+}