Fix SQL Error if no items where found + Fix setting to null

mod/network.php

@@ -346,7 +346,11 @@ function networkConversation(App $a, $items, Pager $pager, $mode, $update, $orde
 	// Set this so that the conversation function can find out contact info for our wall-wall items
 	$a->page_contact = $a->contact;
 
-	$items = (empty($items) ? [] : $items);
+	if (!is_array($items)){
+		Logger::log("Expecting items to be an array. Got " . print_r($items, true));
+		$items = [];
+	}
+
 	$o = conversation($a, $items, $pager, $mode, $update, false, $ordering, local_user());
 
 	if (!$update) {
@@ -390,6 +394,10 @@ function network_content(App $a, $update = 0, $parent = 0)
 		$o = networkThreadedView($a, $update, $parent);
 	}
 
+	if ($o === ''){
+		info("No items found");
+	}
+
 	return $o;
 }
 
@@ -464,6 +472,9 @@ function networkFlatView(App $a, $update = 0)
 		}
 		DBA::close($result);
 
+		if (count($posts) == 0){
+			return '';
+		}
 		$condition = ['uid' => local_user(), 'id' => $posts];
 	} else {
 		$condition = ['uid' => local_user()];

src/Model/FileTag.php

@@ -290,7 +290,11 @@ class FileTag
             return false;
         }
 
-        $fields = ['file' => str_replace($pattern, null, $item['file'])];
+        $fields = ['file' => str_replace($pattern, '', $item['file'])];
+        if ($fields === '') {
+        	$fields = null;
+        }
+
         Item::update($fields, ['id' => $item_id]);
 
         $r = q("SELECT `oid` FROM `term` WHERE `term` = '%s' AND `otype` = %d AND `type` = %d AND `uid` = %d",