Add entry_before_display hook

See https://github.com/FreshRSS/FreshRSS/issues/252

app/views/index/normal.phtml

@@ -35,6 +35,11 @@ if (!empty($this->entries)) {
 		<a href="<?php echo Minz_Url::display(Minz_Request::currentRequest()); ?>"><?php echo _t('new_article'); ?></a>
 	</div><?php
 	foreach ($this->entries as $item) {
+		$item = Minz_ExtensionManager::callHook('entry_before_display', $item);
+		if (is_null($item)) {
+			continue;
+		}
+
 		if ($display_today && $item->isDay(FreshRSS_Days::TODAY, $today)) {
 			?><div class="day" id="day_today"><?php
 				echo _t('today');

app/views/index/reader.phtml

@@ -6,10 +6,13 @@ if (!empty($this->entries)) {
 	$content_width = FreshRSS_Context::$conf->content_width;
 ?>
 
-<div id="stream" class="reader">
-	<?php foreach ($this->entries as $item) { ?>
-
-	<div class="flux<?php echo !$item->isRead() ? ' not_read' : ''; ?><?php echo $item->isFavorite() ? ' favorite' : ''; ?>" id="flux_<?php echo $item->id(); ?>">
+<div id="stream" class="reader"><?php
+	foreach ($this->entries as $item) {
+		$item = Minz_ExtensionManager::callHook('entry_before_display', $item);
+		if (is_null($item)) {
+			continue;
+		}
+	?><div class="flux<?php echo !$item->isRead() ? ' not_read' : ''; ?><?php echo $item->isFavorite() ? ' favorite' : ''; ?>" id="flux_<?php echo $item->id(); ?>">
 		<div class="flux_content">
 			<div class="content <?php echo $content_width; ?>">
 				<?php

lib/Minz/ExtensionManager.php

@@ -13,8 +13,10 @@ class Minz_ExtensionManager {
 
 	private static $ext_auto_enabled = array();
 
+	// List of available hooks. Please keep this list sorted.
 	private static $hook_list = array(
-		'entry_before_insert' => array(),  // function($entry)
+		'entry_before_display' => array(),  // function($entry) -> Entry | null
+		'entry_before_insert' => array(),  // function($entry) -> Entry | null
 	);
 	private static $ext_to_hooks = array();
 
@@ -230,7 +232,7 @@ class Minz_ExtensionManager {
 		$args = func_get_args();
 		unset($args[0]);
 
-		$result = $args;
+		$result = $args[1];
 		foreach (self::$hook_list[$hook_name] as $function) {
 			$result = call_user_func_array($function, $args);