Fix LOOT "ambiguous load order" by merging base ESMs into plugins.txt

MO2's plugins.txt omits implicitly-active base game ESMs — LOOT needs
every plugin listed to determine unambiguous load order. Now merges
entries from loadorder.txt that are missing from plugins.txt before
passing the files to LOOT.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

1 files changed, 53 insertions, 4 deletions

diff --git a/src/src/loot.cpp b/src/src/loot.cpp
index 794cc9b..75ecbbc 100644
--- a/src/src/loot.cpp
+++ b/src/src/loot.cpp
@@ -1350,7 +1350,10 @@ static bool launchLootGui(QWidget* parent, OrganizerCore& core)
   ensureLootSettings(lootDataPath, mo2GameName, folderName, gamePath, localPath);

 

   // Copy the profile's load order files to the local path so LOOT sees

-  // the current load order.

+  // the current load order.  MO2's plugins.txt omits implicitly-active

+  // plugins (base game ESMs) — LOOT needs every plugin listed or it warns

+  // about an "ambiguous load order".  Merge loadorder.txt entries into

+  // plugins.txt so LOOT sees the complete picture.

   QDir().mkpath(localPath);

   QString profilePlugins   = core.profilePath() + "/plugins.txt";

   QString profileLoadOrder = core.profilePath() + "/loadorder.txt";

@@ -1359,12 +1362,58 @@ static bool launchLootGui(QWidget* parent, OrganizerCore& core)
 

   QFile::remove(lootPlugins);

   QFile::remove(lootLoadOrder);

-  if (QFile::exists(profilePlugins)) {

-    QFile::copy(profilePlugins, lootPlugins);

-  }

   if (QFile::exists(profileLoadOrder)) {

     QFile::copy(profileLoadOrder, lootLoadOrder);

   }

+  if (QFile::exists(profilePlugins) && QFile::exists(profileLoadOrder)) {

+    // Build a set of plugins already in plugins.txt (case-insensitive).

+    QFile pluginsFile(profilePlugins);

+    QSet<QString> pluginsListed;

+    QStringList pluginsLines;

+    if (pluginsFile.open(QIODevice::ReadOnly | QIODevice::Text)) {

+      QTextStream in(&pluginsFile);

+      while (!in.atEnd()) {

+        QString line = in.readLine();

+        pluginsLines.append(line);

+        QString name = line.trimmed();

+        if (name.startsWith('*'))

+          name = name.mid(1);

+        if (!name.isEmpty() && !name.startsWith('#'))

+          pluginsListed.insert(name.toLower());

+      }

+      pluginsFile.close();

+    }

+

+    // Read loadorder.txt to find plugins not in plugins.txt (base ESMs).

+    QFile loFile(profileLoadOrder);

+    QStringList missingPlugins;

+    if (loFile.open(QIODevice::ReadOnly | QIODevice::Text)) {

+      QTextStream in(&loFile);

+      while (!in.atEnd()) {

+        QString line = in.readLine().trimmed();

+        if (line.isEmpty() || line.startsWith('#'))

+          continue;

+        if (!pluginsListed.contains(line.toLower())) {

+          // Base game ESMs are always active — mark with *.

+          missingPlugins.append("*" + line);

+        }

+      }

+      loFile.close();

+    }

+

+    // Write merged plugins.txt: missing base ESMs first, then original.

+    QFile outFile(lootPlugins);

+    if (outFile.open(QIODevice::WriteOnly | QIODevice::Text)) {

+      QTextStream out(&outFile);

+      for (const auto& line : missingPlugins)

+        out << line << "\n";

+      for (const auto& line : pluginsLines)

+        out << line << "\n";

+      outFile.close();

+    }

+  } else if (QFile::exists(profilePlugins)) {

+    QFile::copy(profilePlugins, lootPlugins);

+  }

 

   // Mount the FUSE VFS so LOOT sees the merged mod files in the Data directory.

   log::info("Mounting VFS for LOOT...");