feat: Add lazy panel loading support

.gitattributes

@@ -3,6 +3,7 @@
 .gitignore      export-ignore
 ncs.*           export-ignore
 phpstan*.neon   export-ignore
+src/**/*.latte  export-ignore
 tests/          export-ignore
 
 *.php*          diff=php

.github/workflows/coding-style.yml

@@ -14,7 +14,7 @@ jobs:
                   coverage: none
 
             - run: composer create-project nette/code-checker temp/code-checker ^3 --no-progress
-            - run: php temp/code-checker/code-checker --strict-types --no-progress -i tests/Tracy/fixtures -i examples/assets
+            - run: php temp/code-checker/code-checker --strict-types --no-progress -i tests/Tracy/fixtures -i examples/assets -i *.latte
 
 
     nette_cs:

.github/workflows/tests.yml

@@ -37,6 +37,7 @@ jobs:
     code_coverage:
         name: Code Coverage
         runs-on: ubuntu-latest
+        continue-on-error: true
         steps:
             - uses: actions/checkout@v4
             - uses: shivammathur/setup-php@v2

composer.json

@@ -27,7 +27,9 @@
 		"nette/tester": "^2.6",
 		"latte/latte": "^2.5 || ^3.0",
 		"psr/log": "^1.0 || ^2.0 || ^3.0",
-		"phpstan/phpstan": "^2.0@stable"
+		"phpstan/phpstan": "^2.1@stable",
+		"phpstan/extension-installer": "^1.4@stable",
+		"nette/phpstan-rules": "^1.0"
 	},
 	"conflict": {
 		"nette/di": "<3.0"
@@ -46,7 +48,12 @@
 	},
 	"extra": {
 		"branch-alias": {
-			"dev-master": "2.11-dev"
+			"dev-master": "3.0-dev"
+		}
+	},
+	"config": {
+		"allow-plugins": {
+			"phpstan/extension-installer": true
 		}
 	}
 }

examples/lazy-panels.php

@@ -0,0 +1,143 @@
+<?php
+
+declare(strict_types=1);
+
+require __DIR__ . '/../src/tracy.php';
+
+use Tracy\Debugger;
+use Tracy\IBarPanel;
+
+// For security reasons, Tracy is visible only on localhost.
+// You may force Tracy to run in development mode by passing the Debugger::Development instead of Debugger::Detect.
+Debugger::enable(Debugger::Detect, __DIR__ . '/log');
+
+
+/**
+ * Example: A normal (eager) panel — getPanel() is called during the request.
+ */
+class NormalPanel implements IBarPanel
+{
+	public function getTab(): string
+	{
+		return '<span title="Normal Panel">⚡ Normal</span>';
+	}
+
+	public function getPanel(): string
+	{
+		return '<h1>Normal Panel</h1>'
+			. '<div class="tracy-inner">'
+			. '<p>This panel was rendered <strong>during the request</strong> (eager).</p>'
+			. '<p>Time: ' . date('H:i:s') . '</p>'
+			. '</div>';
+	}
+}
+
+
+/**
+ * Example: A "heavy" panel that simulates expensive computation.
+ * When registered with lazy: true, getPanel() is NOT called during the request.
+ * Instead, it is rendered in the shutdown function and served via AJAX on click.
+ */
+class HeavyPanel implements IBarPanel
+{
+	public function getTab(): string
+	{
+		return '<span title="Heavy Panel (lazy)">🐢 Heavy</span>';
+	}
+
+	public function getPanel(): string
+	{
+		// Simulate expensive operation (e.g., database profiling, API calls)
+		usleep(500_000); // 500ms delay
+
+		return '<h1>Heavy Panel (lazy loaded)</h1>'
+			. '<div class="tracy-inner">'
+			. '<p>This panel was rendered <strong>after the response</strong> (lazy).</p>'
+			. '<p>It simulates a 500ms expensive computation.</p>'
+			. '<p>Time: ' . date('H:i:s') . '</p>'
+			. '<table><tr><th>Key</th><th>Value</th></tr>'
+			. '<tr><td>PHP Version</td><td>' . PHP_VERSION . '</td></tr>'
+			. '<tr><td>Memory Peak</td><td>' . number_format(memory_get_peak_usage() / 1024 / 1024, 2) . ' MB</td></tr>'
+			. '<tr><td>Extensions</td><td>' . count(get_loaded_extensions()) . ' loaded</td></tr>'
+			. '</table>'
+			. '</div>';
+	}
+}
+
+
+/**
+ * Example: Another lazy panel showing database-like profiling info.
+ */
+class DatabasePanel implements IBarPanel
+{
+	public function getTab(): string
+	{
+		return '<span title="Database Panel (lazy)">🗄️ DB</span>';
+	}
+
+	public function getPanel(): string
+	{
+		usleep(300_000); // 300ms delay
+
+		$queries = [
+			['SELECT * FROM users WHERE id = 1', '0.5ms'],
+			['SELECT * FROM posts WHERE user_id = 1 ORDER BY created_at DESC LIMIT 10', '2.1ms'],
+			['UPDATE users SET last_login = NOW() WHERE id = 1', '0.3ms'],
+		];
+
+		$html = '<h1>Database Panel (lazy loaded)</h1>'
+			. '<div class="tracy-inner">'
+			. '<p>Simulated database queries — rendered lazily after the response was sent.</p>'
+			. '<table><tr><th>#</th><th>Query</th><th>Time</th></tr>';
+
+		foreach ($queries as $i => [$query, $time]) {
+			$html .= '<tr><td>' . ($i + 1) . '</td><td><code>' . htmlspecialchars($query) . '</code></td><td>' . $time . '</td></tr>';
+		}
+
+		$html .= '</table></div>';
+		return $html;
+	}
+}
+
+
+// Register panels:
+// Normal panel (eager) — rendered during the request
+Debugger::getBar()->addPanel(new NormalPanel, 'example-normal');
+
+// Heavy panel — lazy: true means getPanel() is deferred to shutdown function
+Debugger::getBar()->addPanel(new HeavyPanel, 'example-heavy', lazy: true);
+
+// Database panel — also lazy
+Debugger::getBar()->addPanel(new DatabasePanel, 'example-database', lazy: true);
+
+?>
+<!DOCTYPE html><html class=arrow><link rel="stylesheet" href="assets/style.css">
+
+<h1>Tracy: Lazy Panel Loading Demo</h1>
+
+<h2>How it works</h2>
+<p>This demo shows the <code>lazy: true</code> parameter for <code>Debugger::getBar()->addPanel()</code>.</p>
+
+<ul>
+	<li><strong>⚡ Normal</strong> — A regular panel. Its <code>getPanel()</code> is called during the request.</li>
+	<li><strong>🐢 Heavy</strong> — A lazy panel simulating a 500ms expensive operation. Content loads on click.</li>
+	<li><strong>🗄️ DB</strong> — A lazy panel simulating database query profiling. Content loads on click.</li>
+</ul>
+
+<h2>Usage</h2>
+<pre><code>// Register a lazy panel — getPanel() is NOT called during the request
+Debugger::getBar()->addPanel(new MyExpensivePanel, 'my-panel', lazy: true);
+</code></pre>
+
+<p>Lazy panels have their <code>getTab()</code> called normally (so the tab is always visible),
+but <code>getPanel()</code> is deferred to a shutdown function. The content is stored in the session
+and fetched via AJAX when you click or hover over the panel tab.</p>
+
+<p>This is useful for panels that perform expensive operations like database profiling,
+API call logging, or heavy data analysis — they won't slow down your page response time.</p>
+
+<?php
+
+if (Debugger::$productionMode) {
+	echo '<p><b>For security reasons, Tracy is visible only on localhost. Look into the source code to see how to enable Tracy.</b></p>';
+}

phpstan.neon

@@ -1,33 +1,51 @@
 parameters:
-	level: 6
+	level: 8
 
 	paths:
 		- src
 
-	checkMissingCallableSignature: true
+	fileExtensions:
+		- php
+		- phtml
 
 	ignoreErrors:
 		# Template variables used in required .phtml files via variable scope
 		-
 			identifier: closure.unusedUse
 			path: src/Tracy/Bar/Bar.php
+		-
+			identifier: closure.unusedUse
+			path: src/Tracy/BlueScreen/dist/markdown.phtml
 
 		# Tracy doesn't need generic type parameters for Fiber, ArrayObject, DOMNodeList, etc.
 		-
 			identifier: missingType.generics
 
-		# Private methods called from .phtml template files
-		-
-			identifier: method.unused
-			path: src/Tracy/BlueScreen/BlueScreen.php
-
 		# Runtime validation of callable-string and Closure types
 		-
 			identifier: function.alreadyNarrowedType
+			paths:
+				- src/Tracy/Bar/dist/loader.phtml
+				- src/Tracy/BlueScreen/BlueScreen.php
+				- src/Tracy/Helpers.php
 
 		# Tracy uses dynamic properties on exceptions and panels
 		-
 			identifier: property.notFound
+			paths:
+				- src/Tracy/Bar/dist/info.panel.phtml
+				- src/Tracy/Bar/dist/info.tab.phtml
+				- src/Tracy/Bar/panels/info.panel.php
+				- src/Tracy/Debugger/DevelopmentStrategy.php
+				- src/Tracy/Helpers.php
+
+		# Private methods called from .phtml template files
+		-
+			identifier: method.unused
+			path: src/Tracy/BlueScreen/BlueScreen.php
+		-
+			identifier: method.private
+			path: src/Tracy/BlueScreen/dist
 
 		# PHPStan doesn't track reference assignments to snapshot array
 		-
@@ -74,3 +92,29 @@ parameters:
 		-
 			identifier: missingType.return
 			path: src/Tracy/Logger/ILogger.php
+
+		# Arrow function callback receives class names from get_declared_classes() etc.
+		-
+			identifier: argument.type
+			message: '#class\-string#'
+			path: src/Tracy/Bar/panels/info.panel.php
+
+		# getPanel() returns ?IBarPanel but panel is always registered; dynamic props correct by design
+		-
+			identifier: property.nonObject
+			path: src/Tracy/Debugger/DevelopmentStrategy.php
+
+		# Value::$id and $value are always non-null when used as array keys (snapshot/above maps)
+		-
+			identifier: offsetAccess.invalidOffset
+			paths:
+				- src/Tracy/Dumper/Describer.php
+				- src/Tracy/Dumper/Renderer.php
+
+		# Generated phtml templates use is_bool() as a runtime type guard; PHPStan sees it as always-false for string-typed vars
+		-
+			identifier: function.impossibleType
+			paths:
+				- src/Tracy/Bar/dist
+				- src/Tracy/BlueScreen/dist
+				- src/Tracy/Debugger/dist

src/Bridges/Nette/Bridge.php

@@ -46,16 +46,12 @@ public static function renderMemberAccessException(?\Throwable $e): ?array
 
 		$loc = Tracy\Debugger::mapSource($loc['file'], $loc['line']) ?? $loc;
 		if (preg_match('#Cannot (?:read|write to) an undeclared property .+::\$(\w+), did you mean \$(\w+)\?#A', $e->getMessage(), $m)) {
-			return [
-				'link' => Helpers::editorUri($loc['file'], $loc['line'], 'fix', '->' . $m[1], '->' . $m[2]),
-				'label' => 'fix it',
-			];
+			$link = Helpers::editorUri($loc['file'], $loc['line'], 'fix', '->' . $m[1], '->' . $m[2]);
+			return $link !== null ? ['link' => $link, 'label' => 'fix it'] : null;
 		} elseif (preg_match('#Call to undefined (static )?method .+::(\w+)\(\), did you mean (\w+)\(\)?#A', $e->getMessage(), $m)) {
 			$operator = $m[1] ? '::' : '->';
-			return [
-				'link' => Helpers::editorUri($loc['file'], $loc['line'], 'fix', $operator . $m[2] . '(', $operator . $m[3] . '('),
-				'label' => 'fix it',
-			];
+			$link = Helpers::editorUri($loc['file'], $loc['line'], 'fix', $operator . $m[2] . '(', $operator . $m[3] . '(');
+			return $link !== null ? ['link' => $link, 'label' => 'fix it'] : null;
 		}
 
 		return null;

src/Bridges/Nette/TracyExtension.php

@@ -131,14 +131,14 @@ public function afterCompile(Nette\PhpGenerator\ClassType $class): void
 			}
 
 			$initialize->addBody($builder->formatPhp('if ($logger instanceof Tracy\Logger) $logger->mailer = ?;', [
-				[new Statement(Tracy\Bridges\Nette\MailSender::class, $params), 'send'],
+				[new Statement(Tracy\Bridges\Nette\MailSender::class, $params), 'send'], // TODO: nette/di must be able to create closures
 			]));
 		}
 
 		if ($this->debugMode) {
 			foreach ($config->bar as $item) {
 				if (is_string($item) && str_starts_with($item, '@')) {
-					$item = new Statement(['@' . $builder::THIS_CONTAINER, 'getService'], [substr($item, 1)]);
+					$item = new Statement(['@' . $builder::ThisContainer, 'getService'], [substr($item, 1)]);
 				} elseif (is_string($item)) {
 					$item = new Statement($item);
 				}
@@ -182,7 +182,8 @@ public function afterCompile(Nette\PhpGenerator\ClassType $class): void
 	private function parseErrorSeverity(string|array $value): int
 	{
 		$value = implode('|', (array) $value);
-		$res = (int) @parse_ini_string('e = ' . $value)['e']; // @ may fail
+		$ini = @parse_ini_string('e = ' . $value); // @ may fail
+		$res = (int) ($ini['e'] ?? 0);
 		if (!$res) {
 			throw new Nette\InvalidStateException("Syntax error in expression '$value'");
 		}