page: artist-alias: don't overshadow a normal artist page

Also moves filtering logic into targets().

Author: towerofnix

src/page/artist-alias.js

@@ -1,18 +1,32 @@
 export const description = `redirects for aliased artist names`;
 
 export function targets({wikiData}) {
-  return wikiData.artistData.filter(artist => artist.isAlias);
+  const normalArtistDirectories =
+    wikiData.artistData
+      .filter(artist => !artist.isAlias)
+      .map(artist => artist.directory);
+
+  return (
+    wikiData.artistData
+      .filter(artist => artist.isAlias)
+
+      // Don't generate a redirect page if this aliased name resolves to the
+      // same directory as the original artist! See issue #280.
+      .filter(aliasArtist =>
+        aliasArtist.directory !==
+        aliasArtist.aliasedArtist.directory)
+
+      // And don't generate a redirect page if this aliased name resolves to the
+      // same directory as any *other, non-alias* artist. In that case we really
+      // just need the page (at this directory) to lead to the actual artist with
+      // this directory - not be a redirect. See issue #543.
+      .filter(aliasArtist =>
+        !normalArtistDirectories.includes(aliasArtist.directory)));
 }
 
 export function pathsForTarget(aliasArtist) {
   const {aliasedArtist} = aliasArtist;
 
-  // Don't generate a redirect page if this aliased name resolves to the same
-  // directory as the original artist! See issue #280.
-  if (aliasArtist.directory === aliasedArtist.directory) {
-    return [];
-  }
-
   return [
     {
       type: 'redirect',