From 6c485873b80b61309004efc9d19e6d9975f62bc2 Mon Sep 17 00:00:00 2001
From: David Grudl <david@grudl.com>
Date: Tue, 9 Jul 2024 12:50:36 +0200
Subject: [PATCH] {default} is evaluated lazily

---
 src/Latte/Essential/Nodes/VarNode.php        | 30 ++++++----------
 tests/tags/expected/inheritance.1.parent.php |  4 ++-
 tests/tags/var.default.phpt                  | 37 +++++++++++++++-----
 3 files changed, 43 insertions(+), 28 deletions(-)

diff --git a/src/Latte/Essential/Nodes/VarNode.php b/src/Latte/Essential/Nodes/VarNode.php
index f7cb4c867..cd0a517cc 100644
--- a/src/Latte/Essential/Nodes/VarNode.php
+++ b/src/Latte/Essential/Nodes/VarNode.php
@@ -11,7 +11,6 @@
 
 use Latte\Compiler\Nodes\Php\Expression\AssignNode;
 use Latte\Compiler\Nodes\Php\Expression\VariableNode;
-use Latte\Compiler\Nodes\Php\ExpressionNode;
 use Latte\Compiler\Nodes\Php\Scalar\NullNode;
 use Latte\Compiler\Nodes\StatementNode;
 use Latte\Compiler\PrintContext;
@@ -67,26 +66,19 @@ private static function parseAssignments(Tag $tag, bool $default): array
 	public function print(PrintContext $context): string
 	{
 		$res = [];
-		if ($this->default) {
-			foreach ($this->assignments as $assign) {
+		foreach ($this->assignments as $assign) {
+			if ($this->default) {
 				assert($assign->var instanceof VariableNode);
-				if ($assign->var->name instanceof ExpressionNode) {
-					$var = $assign->var->name->print($context);
-				} else {
-					$var = $context->encodeString($assign->var->name);
-				}
-				$res[] = $var . ' => ' . $assign->expr->print($context);
+				$res[] = $context->format(
+					'%node ??= array_key_exists(%raw, get_defined_vars()) ? %node : %node',
+					$assign->var,
+					$context->encodeString($assign->var->name),
+					$assign->var,
+					$assign->expr,
+				);
+			} else {
+				$res[] = $assign->print($context);
 			}
-
-			return $context->format(
-				'extract([%raw], EXTR_SKIP) %line;',
-				implode(', ', $res),
-				$this->position,
-			);
-		}
-
-		foreach ($this->assignments as $assign) {
-			$res[] = $assign->print($context);
 		}
 
 		return $context->format(
diff --git a/tests/tags/expected/inheritance.1.parent.php b/tests/tags/expected/inheritance.1.parent.php
index cdad6e4fa..1bf626393 100644
--- a/tests/tags/expected/inheritance.1.parent.php
+++ b/tests/tags/expected/inheritance.1.parent.php
@@ -53,7 +53,9 @@ public function prepare(): array
 	{
 		extract($this->params);
 
-		extract(['class' => null, 'namespace' => null, 'top' => true], EXTR_SKIP) /* line %d% */;
+		$class ??= array_key_exists('class', get_defined_vars()) ? $class : null;
+		$namespace ??= array_key_exists('namespace', get_defined_vars()) ? $namespace : null;
+		$top ??= array_key_exists('top', get_defined_vars()) ? $top : true /* line 1 */;
 		return get_defined_vars();
 	}
 
diff --git a/tests/tags/var.default.phpt b/tests/tags/var.default.phpt
index e8e5bf843..dceda2de0 100644
--- a/tests/tags/var.default.phpt
+++ b/tests/tags/var.default.phpt
@@ -42,13 +42,37 @@ test('{var ...}', function () use ($latte) {
 
 
 test('{default ...}', function () use ($latte) {
-	Assert::contains("extract(['var' => null, 'var2' => null], EXTR_SKIP) /*", $latte->compile('{default $var, $var2}'));
-	Assert::contains("extract(['var' => 123], EXTR_SKIP) /*", $latte->compile('{default $var = 123}'));
-	Assert::contains("extract(['var1' => 123, 'var2' => 'nette framework'], EXTR_SKIP) /*", $latte->compile('{default $var1 = 123, $var2 = "nette framework"}'));
+	Assert::match(<<<'XX'
+		%A%
+				$var ??= array_key_exists('var', get_defined_vars()) ? $var : null;
+				$var2 ??= array_key_exists('var2', get_defined_vars()) ? $var2 : null /* line 1 */;
+		%A%
+		XX, $latte->compile('{default $var, $var2}'));
+
+	Assert::contains(
+		'$var ??= array_key_exists(\'var\', get_defined_vars()) ? $var : 123 /* line 1 */;',
+		$latte->compile('{default $var = 123}'),
+	);
+
+	Assert::match(<<<'XX'
+		%A%
+				$var1 ??= array_key_exists('var1', get_defined_vars()) ? $var1 : 123;
+				$var2 ??= array_key_exists('var2', get_defined_vars()) ? $var2 : 'nette framework' /* line 1 */;
+		%A%
+		XX, $latte->compile('{default $var1 = 123, $var2 = "nette framework"}'));
 
 	// types
-	Assert::contains("extract(['var' => 123], EXTR_SKIP) /*", $latte->compile('{default null|int|string[] $var = 123}'));
-	Assert::contains("extract(['var1' => 123, 'var2' => 'nette framework'], EXTR_SKIP) /*", $latte->compile('{default int|string[] $var1 = 123, ?class $var2 = "nette framework"}'));
+	Assert::contains(
+		'$var ??= array_key_exists(\'var\', get_defined_vars()) ? $var : 123 /* line 1 */;',
+		$latte->compile('{default null|int|string[] $var = 123}'),
+	);
+
+	Assert::match(<<<'XX'
+		%A%
+				$var1 ??= array_key_exists('var1', get_defined_vars()) ? $var1 : 123;
+				$var2 ??= array_key_exists('var2', get_defined_vars()) ? $var2 : 'nette framework' /* line 1 */;
+		%A%
+		XX, $latte->compile('{default int|string[] $var1 = 123, ?class $var2 = "nette framework"}'));
 
 	// errors
 	Assert::exception(
@@ -62,7 +86,4 @@ test('{default ...}', function () use ($latte) {
 		Latte\CompileException::class,
 		'Unexpected end in {default} (on line 1 at column 30)',
 	);
-
-	// preprocess
-	Assert::contains("extract(['var1' => true ? 'a' : null], EXTR_SKIP) /*", $latte->compile('{default $var1 = true ? a}'));
 });