From 0170ec19c7723d3dd51c7936fc55e68a882135fe Mon Sep 17 00:00:00 2001
From: "J. King" <jking@jkingweb.ca>
Date: Sat, 6 Jul 2024 11:01:00 -0400
Subject: [PATCH] Fix language-loading infinite loop when throwing exceptions

This loop has existed since the very beginning, and was only ever papered over instead of actually fixing it.
---
 lib/Lang.php             | 24 +++++++++++++++++-------
 tests/lib/Lang/Setup.php |  5 +----
 2 files changed, 18 insertions(+), 11 deletions(-)

diff --git a/lib/Lang.php b/lib/Lang.php
index 37ffb6f3..82bb8d48 100644
--- a/lib/Lang.php
+++ b/lib/Lang.php
@@ -198,13 +198,17 @@ class Lang {
             // otherwise start with the strings we already have if we're going from e.g. "fr" to "fr_ca"
             $strings[] = $this->strings;
         }
-        // read files in reverse order
-        $files = array_reverse($files);
-        foreach ($files as $file) {
+        $loaded = array_diff($loaded, $files);
+        $toThrow = null;
+        while ($files) {
+            // read files in reverse order
+            $file = array_pop($files);
             if (!file_exists($this->path."$file.php")) {
-                throw new Lang\Exception("fileMissing", $file);
+                $toThrow = ["fileMissing", $file];
+                break;
             } elseif (!is_readable($this->path."$file.php")) {
-                throw new Lang\Exception("fileUnreadable", $file);
+                $toThrow = ["fileUnreadable", $file];
+                break;
             }
             try {
                 // we use output buffering in case the language file is corrupted
@@ -216,16 +220,22 @@ class Lang {
                 ob_end_clean();
             }
             if (!is_array($arr)) {
-                throw new Lang\Exception("fileCorrupt", $file);
+                $toThrow = ["fileCorrupt", $file];
+                break;
             }
             $strings[] = $arr;
+            $loaded[] = $file;
         }
         // apply the results and return
-        $this->strings = call_user_func_array("array_replace_recursive", $strings);
+        $this->strings = array_replace_recursive(...$strings);
         $this->loaded = $loaded;
         $this->locale = $this->wanted;
         $this->synched = true;
         $this->formatter = null;
+        if ($toThrow) {
+            // if not all requested files could be loaded successfully, throw an exception
+            throw new Lang\Exception(...$toThrow);
+        }
         return true;
     }
 }
diff --git a/tests/lib/Lang/Setup.php b/tests/lib/Lang/Setup.php
index 0969bf6b..71140957 100644
--- a/tests/lib/Lang/Setup.php
+++ b/tests/lib/Lang/Setup.php
@@ -43,11 +43,8 @@ trait Setup {
             return Glob::glob($this->path."*.php");
         });
         $this->l = $this->l->get();
-        // create a mock Lang object so as not to create a dependency loop
         self::clearData(false);
-        Arsse::$lang = $this->mock(Lang::class);
-        Arsse::$lang->msg->returns("");
-        Arsse::$lang = Arsse::$lang->get();
+        Arsse::$lang = $this->l;
         // call the additional setup method if it exists
         if (method_exists($this, "setUpSeries")) {
             $this->setUpSeries();