From 7497ff2514668864817285b50cf87f1a173b08e8 Mon Sep 17 00:00:00 2001
From: Alexander Capehart <alex@oxycblt.org>
Date: Sat, 28 Dec 2024 15:11:28 -0700
Subject: [PATCH] musikr: fix crash when no mbids used

---
 .../main/java/org/oxycblt/musikr/graph/MusicGraph.kt | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/musikr/src/main/java/org/oxycblt/musikr/graph/MusicGraph.kt b/musikr/src/main/java/org/oxycblt/musikr/graph/MusicGraph.kt
index d08a979ce..121a53cf4 100644
--- a/musikr/src/main/java/org/oxycblt/musikr/graph/MusicGraph.kt
+++ b/musikr/src/main/java/org/oxycblt/musikr/graph/MusicGraph.kt
@@ -172,6 +172,10 @@ private class MusicGraphBuilderImpl : MusicGraph.Builder {
     }
 
     private fun meldGenreVertices(src: GenreVertex, dst: GenreVertex) {
+        if (src == dst) {
+            // Same vertex, do nothing
+            return
+        }
         // Link all songs and artists from the irrelevant genre to the relevant genre.
         dst.songVertices.addAll(src.songVertices)
         dst.artistVertices.addAll(src.artistVertices)
@@ -229,6 +233,10 @@ private class MusicGraphBuilderImpl : MusicGraph.Builder {
     }
 
     private fun meldArtistVertices(src: ArtistVertex, dst: ArtistVertex) {
+        if (src == dst) {
+            // Same vertex, do nothing
+            return
+        }
         // Link all songs and albums from the irrelevant artist to the relevant artist.
         dst.songVertices.addAll(src.songVertices)
         dst.albumVertices.addAll(src.albumVertices)
@@ -296,6 +304,10 @@ private class MusicGraphBuilderImpl : MusicGraph.Builder {
     }
 
     private fun meldAlbumVertices(src: AlbumVertex, dst: AlbumVertex) {
+        if (src == dst) {
+            // Same vertex, do nothing
+            return
+        }
         // Link all songs and artists from the irrelevant album to the relevant album.
         dst.songVertices.addAll(src.songVertices)
         dst.artistVertices.addAll(src.artistVertices)