--- /dev/null
+<?php
+
+namespace Drupal\kint\Twig;
+
+/**
+ * Provides the Kint debugging function within Twig templates.
+ */
+class KintExtension extends \Twig_Extension {
+
+ /**
+ * {@inheritdoc}
+ */
+ public function getName() {
+ return 'kint';
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function getFunctions() {
+ return array(
+ new \Twig_SimpleFunction('kint', array($this, 'kint'), array(
+ 'is_safe' => array('html'),
+ 'needs_environment' => TRUE,
+ 'needs_context' => TRUE,
+ 'is_variadic' => TRUE,
+ )),
+ );
+ }
+
+ /**
+ * Provides Kint function to Twig templates.
+ *
+ * Handles 0, 1, or multiple arguments.
+ *
+ * Code derived from https://github.com/barelon/CgKintBundle.
+ *
+ * @param \Twig_Environment $env
+ * The twig environment instance.
+ * @param array $context
+ * An array of parameters passed to the template.
+ * @param array $args
+ * An array of parameters passed the function.
+ *
+ * @return string
+ * String representation of the input variables.
+ */
+ public function kint(\Twig_Environment $env, array $context, array $args = []) {
+ // Don't do anything unless twig_debug is enabled. This reads from the Twig
+ // environment, not Drupal Settings, so a container rebuild is necessary
+ // when toggling twig_debug on and off. We can consider injecting Settings.
+ if (!$env->isDebug()) {
+ return;
+ }
+ kint_require();
+ // Don't display where Kint was called from.
+ // @todo Can we add information about which template Kint was called from?
+ \Kint::$displayCalledFrom = FALSE;
+
+ // No arguments passed to kint(), display full Twig context.
+ if (empty($args)) {
+ $kint_variable = array();
+ foreach ($context as $key => $value) {
+ if (!$value instanceof \Twig_Template) {
+ $kint_variable[$key] = $value;
+ }
+ }
+
+ $result = @\Kint::dump($kint_variable);
+ $output = str_replace('$kint_variable', 'Twig context', $result);
+ }
+ else {
+ // Try to get the names of variables from the Twig template.
+ $parameters = $this->getTwigFunctionParameters();
+
+ // If there is only one argument, pass to Kint without too much hassle.
+ if (count($args) == 1) {
+ $kint_variable = reset($args);
+ $variable_name = reset($parameters);
+ $result = @\Kint::dump($kint_variable);
+ // Replace $kint_variable with the name of the variable in the Twig
+ // template.
+ $output = str_replace('$kint_variable', $variable_name, $result);
+ }
+ else {
+ $kint_args = [];
+ // Build an array of variable to pass to Kint.
+ // @todo Can we just call_user_func_array while still retaining the
+ // variable names?
+ foreach ($args as $index => $arg) {
+ // Prepend a unique index to allow debugging the same variable more
+ // than once in the same Kint dump.
+ $name = !empty($parameters[$index]) ? $parameters[$index] : $index;
+ $kint_args['_index_' . $index . '_' . $name] = $arg;
+ }
+
+ $result = @\Kint::dump($kint_args);
+ // Display a comma separated list of the variables contained in this group.
+ $output = str_replace('$kint_args', implode(', ', $parameters), $result);
+ // Remove unique indexes from output.
+ $output = preg_replace('/_index_([0-9]+)_/', '', $output);
+ }
+ }
+
+ return $output;
+ }
+
+ /**
+ * Gets the twig function parameters for the current invocation.
+ *
+ * @return array
+ * The detected twig function parameters.
+ */
+ protected function getTwigFunctionParameters() {
+ $callee = NULL;
+ $template = NULL;
+
+ $backtrace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS | DEBUG_BACKTRACE_PROVIDE_OBJECT);
+
+ foreach ($backtrace as $index => $trace) {
+ if (isset($trace['object']) && $trace['object'] instanceof \Twig_Template && 'Twig_Template' !== get_class($trace['object'])) {
+ $template = $trace['object'];
+ $callee = $backtrace[$index - 1];
+ break;
+ }
+ }
+
+ $parameters = [];
+
+ /** @var \Twig_Template $template */
+ if (NULL !== $template && NULL !== $callee) {
+ $line_number = $callee['line'];
+ $debug_infos = $template->getDebugInfo();
+
+ if (isset($debug_infos[$line_number])) {
+ $source_line = $debug_infos[$line_number];
+ $source_file_name = $template->getTemplateName();
+
+ if (is_readable($source_file_name)) {
+ $source = file($source_file_name, FILE_IGNORE_NEW_LINES);
+ $line = $source[$source_line - 1];
+
+ preg_match('/kint\((.+)\)/', $line, $matches);
+ if (isset($matches[1])) {
+ $parameters = array_map('trim', explode(',', $matches[1]));
+ }
+ }
+ }
+ }
+
+ return $parameters;
+ }
+
+}