added n:else

src/Latte/Essential/CoreExtension.php

@@ -100,6 +100,7 @@ public function getTags(): array
 			'ifset' => [Nodes\IfNode::class, 'create'],
 			'ifchanged' => [Nodes\IfChangedNode::class, 'create'],
 			'n:ifcontent' => [Nodes\IfContentNode::class, 'create'],
+			'n:else' => [Nodes\NElseNode::class, 'create'],
 			'switch' => [Nodes\SwitchNode::class, 'create'],
 		];
 	}
@@ -198,6 +199,7 @@ public function getPasses(): array
 			'overwrittenVariables' => [Passes::class, 'overwrittenVariablesPass'],
 			'customFunctions' => fn(TemplateNode $node) => Passes::customFunctionsPass($node, $this->functions),
 			'moveTemplatePrintToHead' => [Passes::class, 'moveTemplatePrintToHeadPass'],
+			'nElse' => [Nodes\NElseNode::class, 'processPass'],
 		];
 	}
 

src/Latte/Essential/Nodes/NElseNode.php

@@ -0,0 +1,82 @@
+<?php
+
+/**
+ * This file is part of the Latte (https://latte.nette.org)
+ * Copyright (c) 2008 David Grudl (https://davidgrudl.com)
+ */
+
+declare(strict_types=1);
+
+namespace Latte\Essential\Nodes;
+
+use Latte\CompileException;
+use Latte\Compiler\Node;
+use Latte\Compiler\Nodes;
+use Latte\Compiler\Nodes\AreaNode;
+use Latte\Compiler\Nodes\StatementNode;
+use Latte\Compiler\Nodes\TemplateNode;
+use Latte\Compiler\NodeTraverser;
+use Latte\Compiler\PrintContext;
+use Latte\Compiler\Tag;
+
+
+/**
+ * n:else
+ */
+final class NElseNode extends StatementNode
+{
+	public AreaNode $content;
+
+
+	/** @return \Generator<int, ?array, array{AreaNode, ?Tag}, static> */
+	public static function create(Tag $tag): \Generator
+	{
+		$node = $tag->node = new static;
+		[$node->content] = yield;
+		return $node;
+	}
+
+
+	public function print(PrintContext $context): string
+	{
+		throw new \LogicException('Cannot directly print');
+	}
+
+
+	public function &getIterator(): \Generator
+	{
+		yield $this->content;
+	}
+
+
+	public static function processPass(TemplateNode $node): void
+	{
+		(new NodeTraverser)->traverse($node, function (Node $node) {
+			if ($node instanceof Nodes\FragmentNode) {
+				for ($i = count($node->children) - 1; $i >= 0; $i--) {
+					$child = $node->children[$i];
+					if (!$child instanceof self) {
+						continue;
+					}
+
+					array_splice($node->children, $i, 1);
+					$prev = $node->children[--$i] ?? null;
+					if ($prev instanceof Nodes\TextNode && trim($prev->content) === '') {
+						array_splice($node->children, $i, 1);
+						$prev = $node->children[--$i] ?? null;
+					}
+
+					if (!$prev instanceof IfNode && !$prev instanceof ForeachNode && !$prev instanceof TryNode) {
+						throw new CompileException('n:else must be immediately after n:if / n:try / n:foreach.', $child->position);
+					} elseif ($prev->else) {
+						throw new CompileException('Multiple "else" found.', $child->position);
+					}
+
+					$prev->else = $child->content;
+				}
+			} elseif ($node instanceof self) {
+				throw new CompileException('n:else must be immediately after n:if / n:try / n:foreach.', $node->position);
+			}
+		});
+	}
+}

tests/tags/n-else.phpt

@@ -0,0 +1,142 @@
+<?php
+
+/**
+ * n:else
+ */
+
+declare(strict_types=1);
+
+use Tester\Assert;
+
+require __DIR__ . '/../bootstrap.php';
+
+
+$latte = new Latte\Engine;
+$latte->setLoader(new Latte\Loaders\StringLoader);
+
+// errors
+Assert::exception(
+	fn() => $latte->compile('<span n:else></span>'),
+	Latte\CompileException::class,
+	'n:else must be immediately after n:if / n:try / n:foreach (on line 1 at column 7)',
+);
+
+Assert::exception(
+	fn() => $latte->compile('<div n:if=1>in</div> ... <span n:else></span>'),
+	Latte\CompileException::class,
+	'n:else must be immediately after n:if / n:try / n:foreach (on line 1 at column 32)',
+);
+
+Assert::exception(
+	fn() => $latte->compile('<div n:inner-if=1>in</div> <span n:else></span>'),
+	Latte\CompileException::class,
+	'n:else must be immediately after n:if / n:try / n:foreach (on line 1 at column 34)',
+);
+
+Assert::exception(
+	fn() => $latte->compile('{if true}in1{else}in2{/if} <span n:else></span>'),
+	Latte\CompileException::class,
+	'Multiple "else" found (on line 1 at column 34)',
+);
+
+
+// n:if & n:else
+Assert::match(
+	<<<'XX'
+		begin
+		<div>in1</div>
+		end
+		XX,
+	$latte->renderToString(
+		<<<'XX'
+			begin
+			<div n:if=1>in1</div>
+			<p n:else>else</p>
+			end
+			XX,
+	),
+);
+
+Assert::match(
+	<<<'XX'
+		begin
+		<p>else</p>
+		end
+		XX,
+	$latte->renderToString(
+		<<<'XX'
+			begin
+			<div n:if=0>in1</div>
+			<p n:else>else</p>
+			end
+			XX,
+	),
+);
+
+
+// n:foreach & n:else
+Assert::match(
+	<<<'XX'
+		begin
+		<div>in1</div>
+		end
+		XX,
+	$latte->renderToString(
+		<<<'XX'
+			begin
+			<div n:foreach="[1] as $x">in1</div>
+			<p n:else>else</p>
+			end
+			XX,
+	),
+);
+
+Assert::match(
+	<<<'XX'
+		begin
+		<p>else</p>
+		end
+		XX,
+	$latte->renderToString(
+		<<<'XX'
+			begin
+			<div n:foreach="[] as $x">in1</div>
+			<p n:else>else</p>
+			end
+			XX,
+	),
+);
+
+
+// n:try & n:else
+Assert::match(
+	<<<'XX'
+		begin
+		<div>in1</div>
+		end
+		XX,
+	$latte->renderToString(
+		<<<'XX'
+			begin
+			<div n:try>in1</div>
+			<p n:else>else</p>
+			end
+			XX,
+	),
+);
+
+Assert::match(
+	<<<'XX'
+		begin
+		<p>else</p>
+		end
+		XX,
+	$latte->renderToString(
+		<<<'XX'
+			begin
+			<div n:try>in1 {rollback} in2</div>
+			<p n:else>else</p>
+			end
+			XX,
+	),
+);