BUGFIX: parenthesis in expressions

previously `ExpressionNode::fromString("(foo)")` couldnt be parsed (it worked though when used in return statement of a module)

but the real fix, is that you couldnt write `return ((foo))`
as $tokens is reassigned but not passed by ref

Author: mhsdesign

src/Parser/Ast/ExpressionNode.php

@@ -39,10 +39,11 @@ private function __construct(
 
     public static function fromString(string $expressionAsString): self
     {
+        $tokens = Tokenizer::fromSource(
+            Source::fromString($expressionAsString)
+        )->getIterator();
         return self::fromTokens(
-            Tokenizer::fromSource(
-                Source::fromString($expressionAsString)
-            )->getIterator()
+            $tokens
         );
     }
 
@@ -51,7 +52,7 @@ public static function fromString(string $expressionAsString): self
      * @param Precedence $precedence
      * @return self
      */
-    public static function fromTokens(\Iterator $tokens, Precedence $precedence = Precedence::SEQUENCE): self
+    public static function fromTokens(\Iterator &$tokens, Precedence $precedence = Precedence::SEQUENCE): self
     {
         Scanner::skipSpaceAndComments($tokens);
 
@@ -62,7 +63,7 @@ public static function fromTokens(\Iterator $tokens, Precedence $precedence = Pr
                 $lookAhead->shift();
 
                 while (true) {
-                    switch ($lookAhead->type()) {
+                    switch (Scanner::isEnd($lookAhead->tokens) ?: $lookAhead->type()) {
                         case TokenType::STRING:
                         case TokenType::COLON:
                         case TokenType::COMMA:

src/Parser/Tokenizer/LookAhead.php

@@ -58,7 +58,9 @@ public function getIterator(): \Iterator
             yield $token;
         }
 
-        yield from $this->tokens;
+        if (!Scanner::isEnd($this->tokens)) {
+            yield from $this->tokens;
+        }
     }
 
     public function shift(): void

src/Parser/Tokenizer/Scanner.php

@@ -165,4 +165,20 @@ public static function isEnd(\Iterator $tokens): bool
     {
         return !$tokens->valid();
     }
+
+    /**
+     * @param \Iterator<mixed,Token> $tokens
+     */
+    public static function debugPrint(\Iterator $tokens): string
+    {
+        $tokensAsArray = [];
+        while ($tokens->valid()) {
+            $tokensAsArray[] = [
+                "type" => $tokens->current()->type,
+                "value" => $tokens->current()->value
+            ];
+            $tokens->next();
+        }
+        return json_encode($tokensAsArray, JSON_PRETTY_PRINT | JSON_THROW_ON_ERROR);
+    }
 }

test/Unit/Target/Php/Transpiler/Identifier/IdentifierTranspilerTest.php

@@ -23,10 +23,13 @@
 namespace PackageFactory\ComponentEngine\Test\Unit\Target\Php\Transpiler\Identifier;
 
 use PackageFactory\ComponentEngine\Parser\Ast\EnumDeclarationNode;
+use PackageFactory\ComponentEngine\Parser\Ast\ExpressionNode;
 use PackageFactory\ComponentEngine\Parser\Ast\IdentifierNode;
+use PackageFactory\ComponentEngine\Target\Php\Transpiler\Expression\ExpressionTranspiler;
 use PackageFactory\ComponentEngine\Test\Unit\TypeSystem\Scope\Fixtures\DummyScope;
 use PackageFactory\ComponentEngine\Target\Php\Transpiler\Identifier\IdentifierTranspiler;
 use PackageFactory\ComponentEngine\TypeSystem\Type\EnumType\EnumStaticType;
+use PackageFactory\ComponentEngine\TypeSystem\Type\StringType\StringType;
 use PHPUnit\Framework\TestCase;
 
 final class IdentifierTranspilerTest extends TestCase
@@ -80,4 +83,37 @@ public function transpilesIdentifierNodesReferringToEnums(): void
             $actualTranspilationResult
         );
     }
-}
+
+
+    public function identifierInParenthesisExamples(): mixed
+    {
+        // @todo find a better place for these tests, as we actually test the ExpressionNode
+        return [
+            '(foo)' => ['(foo)', '$this->foo'],
+            '((foo))' => ['((foo))', '$this->foo'],
+            '(((foo)))' => ['(((foo)))', '$this->foo']
+        ];
+    }
+
+    /**
+     * @dataProvider identifierInParenthesisExamples
+     * @test
+     */
+    public function identifierInParenthesis(string $expression, string $expectedTranspilationResult): void
+    {
+        $expressionTranspiler = new ExpressionTranspiler(
+            scope: new DummyScope([
+                "foo" => StringType::get()
+            ])
+        );
+
+        $actualTranspilationResult = $expressionTranspiler->transpile(
+            ExpressionNode::fromString($expression)
+        );
+
+        $this->assertEquals(
+            $expectedTranspilationResult,
+            $actualTranspilationResult
+        );
+    }
+}