From 276395e5f47165950aa609315afb33a251e76062 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E5=BC=98=E9=9F=AC=20=E5=BC=A0?= <hongtao_zhang@outlook.com>
Date: Tue, 9 Feb 2021 15:59:55 +0800
Subject: [PATCH] Use customized distinctBy instead of customized
 equalitycomparator

---
 .../Programs/Win32.cs                          | 18 ++++++------------
 1 file changed, 6 insertions(+), 12 deletions(-)

diff --git a/Plugins/Flow.Launcher.Plugin.Program/Programs/Win32.cs b/Plugins/Flow.Launcher.Plugin.Program/Programs/Win32.cs
index f2adbf243..d73483818 100644
--- a/Plugins/Flow.Launcher.Plugin.Program/Programs/Win32.cs
+++ b/Plugins/Flow.Launcher.Plugin.Program/Programs/Win32.cs
@@ -446,18 +446,13 @@ namespace Flow.Launcher.Plugin.Program.Programs
             }
         }
 
-        private class Win32ComparatorWithDescription : IEqualityComparer<Win32>
+        public static IEnumerable<T> DistinctBy<T, R>(IEnumerable<T> source, Func<T,R> selector)
         {
-            public static readonly Win32ComparatorWithDescription Default = new Win32ComparatorWithDescription();
-
-            public bool Equals(Win32 x, Win32 y)
+            var set = new HashSet<R>();
+            foreach (var item in source)
             {
-                return x?.Description == y?.Description;
-            }
-
-            public int GetHashCode(Win32 obj)
-            {
-                return obj.Description.GetHashCode();
+                if (set.Add(selector(item)))
+                    yield return item;
             }
         }
 
@@ -467,8 +462,7 @@ namespace Flow.Launcher.Plugin.Program.Programs
                 .SelectMany(g =>
                 {
                     if (g.Count() > 1)
-                        return g.Where(p => !string.IsNullOrEmpty(p.Description))
-                            .Distinct(Win32ComparatorWithDescription.Default);
+                        return DistinctBy(g.Where(p => !string.IsNullOrEmpty(p.Description)), x => x.Description);
                     return g;
                 }).ToArray();
         }