Fix phpstan/phpstan#8744: Fix deprecated string interpolation syntax

src/Parser/DeprecatedInterpolatedStringVisitor.php

@@ -0,0 +1,56 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Parser;
+
+use Override;
+use PhpParser\Node;
+use PhpParser\Node\Expr\ArrayDimFetch;
+use PhpParser\Node\Expr\Variable;
+use PhpParser\Node\Scalar\InterpolatedString;
+use PhpParser\NodeVisitorAbstract;
+use PhpParser\Token;
+use PHPStan\DependencyInjection\AutowiredService;
+
+#[AutowiredService]
+final class DeprecatedInterpolatedStringVisitor extends NodeVisitorAbstract implements TokenAwareVisitor
+{
+	public const ATTRIBUTE_NAME = 'isDeprecatedInterpolatedString';
+
+	/**
+	 * @var Token[]
+	 */
+	protected array $tokens = [];
+
+	#[Override]
+	public function setTokens(array $tokens): void
+	{
+		$this->tokens = $tokens;
+	}
+
+	#[Override]
+	public function enterNode(Node $node): ?Node
+	{
+		if (!$node instanceof InterpolatedString) {
+			return null;
+		}
+
+		foreach ($node->parts as $part) {
+			if (!$part instanceof Variable && !($part instanceof ArrayDimFetch && $part->var instanceof Variable)) {
+				continue;
+			}
+			$startTokenPos = $part->getStartTokenPos();
+			if (!isset($this->tokens[$startTokenPos])) {
+				continue;
+			}
+			$startToken = (string) $this->tokens[$startTokenPos];
+			if ($startToken !== '${') {
+				continue;
+			}
+
+			$node->setAttribute(self::ATTRIBUTE_NAME, true);
+		}
+
+		return null;
+	}
+
+}

src/Parser/RichParser.php

@@ -93,6 +93,9 @@ public function parseString(string $sourceCode): array
 		$nodeTraverser->addVisitor($traitCollectingVisitor);
 
 		foreach ($this->container->getServicesByTag(self::VISITOR_SERVICE_TAG) as $visitor) {
+			if ($visitor instanceof TokenAwareVisitor) {
+				$visitor->setTokens($tokens);
+			}
 			$nodeTraverser->addVisitor($visitor);
 		}
 

src/Parser/TokenAwareVisitor.php

@@ -0,0 +1,20 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Parser;
+
+use PhpParser\Token;
+
+/**
+ * A node visitor that is aware of the parser tokens.
+ *
+ * @api
+ */
+interface TokenAwareVisitor
+{
+
+	/**
+	 * @param Token[] $tokens
+	 */
+	public function setTokens(array $tokens): void;
+
+}

src/Php/PhpVersion.php

@@ -266,6 +266,11 @@ public function deprecatesDynamicProperties(): bool
 		return $this->versionId >= 80200;
 	}
 
+	public function deprecatesStringInterpolation(): bool
+	{
+		return $this->versionId >= 80200;
+	}
+
 	public function strSplitReturnsEmptyArray(): bool
 	{
 		return $this->versionId >= 80200;

src/Rules/String/InterpolatedStringRule.php

@@ -0,0 +1,68 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Rules\String;
+
+use PhpParser\Node;
+use PhpParser\Node\Expr\ArrayDimFetch;
+use PhpParser\Node\Expr\Variable;
+use PhpParser\Node\Scalar\InterpolatedString;
+use PHPStan\Analyser\Scope;
+use PHPStan\DependencyInjection\RegisteredRule;
+use PHPStan\Parser\DeprecatedInterpolatedStringVisitor;
+use PHPStan\Php\PhpVersion;
+use PHPStan\Rules\Rule;
+use PHPStan\Rules\RuleErrorBuilder;
+use function is_string;
+
+/**
+ * @implements Rule<InterpolatedString>
+ */
+#[RegisteredRule(level: 0)]
+final class InterpolatedStringRule implements Rule
+{
+
+	public function __construct(
+		private PhpVersion $phpVersion,
+	)
+	{
+	}
+
+	public function getNodeType(): string
+	{
+		return InterpolatedString::class;
+	}
+
+	public function processNode(Node $node, Scope $scope): array
+	{
+		if (!$this->phpVersion->deprecatesStringInterpolation()) {
+			return [];
+		}
+
+		if ($node->getAttribute(DeprecatedInterpolatedStringVisitor::ATTRIBUTE_NAME) !== true) {
+			return [];
+		}
+
+		foreach ($node->parts as $part) {
+			if (!$part instanceof Variable && !($part instanceof ArrayDimFetch && $part->var instanceof Variable)) {
+				continue;
+			}
+
+			if ($part instanceof ArrayDimFetch || (is_string($part->name))) {
+				$deprecatedMessage = 'Using ${var} in strings is deprecated in PHP 8.2. Use {$var} instead.';
+			} else {
+				$deprecatedMessage = 'Using ${expr} (variable variables) in strings is deprecated in PHP 8.2. Use {${expr}} instead.';
+			}
+
+			return [
+				RuleErrorBuilder::message($deprecatedMessage)
+					->identifier('interpolatedstring.deprecated')
+					->line($node->getStartLine())
+					->fixNode($node, static fn () => new InterpolatedString($node->parts, $node->getAttributes()))
+					->build(),
+			];
+		}
+
+		return [];
+	}
+
+}

tests/PHPStan/Rules/String/InterpolatedStringRuleTest.php

@@ -0,0 +1,55 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Rules\String;
+
+use PHPStan\Php\PhpVersion;
+use PHPStan\Rules\Rule as TRule;
+use PHPStan\Testing\RuleTestCase;
+use PHPUnit\Framework\Attributes\RequiresPhp;
+use const PHP_VERSION_ID;
+
+/**
+ * @extends RuleTestCase<InterpolatedStringRule>
+ */
+class InterpolatedStringRuleTest extends RuleTestCase
+{
+
+	protected function getRule(): TRule
+	{
+		return new InterpolatedStringRule(new PhpVersion(PHP_VERSION_ID));
+	}
+
+	#[RequiresPhp('>= 8.2')]
+	public function testRule(): void
+	{
+		$this->analyse([__DIR__ . '/data/interpolated-string.php'], [
+			[
+				'Using ${var} in strings is deprecated in PHP 8.2. Use {$var} instead.',
+				17,
+			],
+			[
+				'Using ${expr} (variable variables) in strings is deprecated in PHP 8.2. Use {${expr}} instead.',
+				18,
+			],
+			[
+				'Using ${expr} (variable variables) in strings is deprecated in PHP 8.2. Use {${expr}} instead.',
+				19,
+			],
+			[
+				'Using ${var} in strings is deprecated in PHP 8.2. Use {$var} instead.',
+				20,
+			],
+			[
+				'Using ${expr} (variable variables) in strings is deprecated in PHP 8.2. Use {${expr}} instead.',
+				23,
+			],
+		]);
+	}
+
+	#[RequiresPhp('>= 8.2')]
+	public function testFix(): void
+	{
+		$this->fix(__DIR__ . '/data/interpolated-string.php', __DIR__ . '/data/interpolated-string.php.fixed');
+	}
+
+}

tests/PHPStan/Rules/String/data/interpolated-string.php

@@ -0,0 +1,23 @@
+<?php // lint >= 8.2
+
+namespace Bug8744Traits;
+
+class Test
+{
+    public function getMethod()
+    {
+        return 'foo';
+    }
+}
+
+const foo = 'bar';
+$foo = 'foo';
+$bar = 'bar';
+$array = ['baz'];
+var_dump("${foo}");
+var_dump("${(foo)}");
+var_dump("${$foo}");
+var_dump("${array[0]}");
+
+$object = new Test();
+var_dump("${$object->getMethod()}");

tests/PHPStan/Rules/String/data/interpolated-string.php.fixed

@@ -0,0 +1,23 @@
+<?php // lint >= 8.2
+
+namespace Bug8744Traits;
+
+class Test
+{
+    public function getMethod()
+    {
+        return 'foo';
+    }
+}
+
+const foo = 'bar';
+$foo = 'foo';
+$bar = 'bar';
+$array = ['baz'];
+var_dump("{$foo}");
+var_dump("{${foo}}");
+var_dump("{${$foo}}");
+var_dump("{$array[0]}");
+
+$object = new Test();
+var_dump("{${$object->getMethod()}}");