From d5097a5e971c46912188a9004b2289cff3798221 Mon Sep 17 00:00:00 2001
From: yassin <135610141+achengli@users.noreply.github.com>
Date: Sun, 18 Aug 2024 01:45:50 +0200
Subject: [PATCH] Performance issue with fish shell (#1483)

The fish shell takes a long time to open an instance, this is because an instance of Brew is running to initialize packages when it is certainly not required to activate it, for example, open a simple terminal to edit some file

Co-authored-by: achengli <achengli@github.com>
---
 .../usr/share/fish/vendor_conf.d/brew.fish    | 28 ++++++++++++++-----
 1 file changed, 21 insertions(+), 7 deletions(-)

diff --git a/system_files/overrides/usr/share/fish/vendor_conf.d/brew.fish b/system_files/overrides/usr/share/fish/vendor_conf.d/brew.fish
index 1ddb1c68..c0d51f0f 100644
--- a/system_files/overrides/usr/share/fish/vendor_conf.d/brew.fish
+++ b/system_files/overrides/usr/share/fish/vendor_conf.d/brew.fish
@@ -1,18 +1,32 @@
 #!/usr/bin/fish
 #shellcheck disable=all
-if status --is-interactive
-    if [ -d /home/linuxbrew/.linuxbrew ]
+set -g __brew_instance_initialize 0
+set -g __brew_binary /home/linuxbrew/.linuxbrew/bin/brew
+
+function brew_new_instance
+  alias brew=$__brew_binary
+  if test $__brew_instance_initialize = 0
+    if status --is-interactive
+      if [ -d /home/linuxbrew/.linuxbrew ]
         eval "$(/home/linuxbrew/.linuxbrew/bin/brew shellenv)"
         if [ -w /home/linuxbrew/.linuxbrew ]
-            if  [ ! -L (brew --prefix)/share/fish/vendor_completions.d/brew ]
-                brew completions link > /dev/null
-            end
+          if  [ ! -L (brew --prefix)/share/fish/vendor_completions.d/brew ]
+            brew completions link > /dev/null
+          end
         end
         if test -d (brew --prefix)/share/fish/completions
-            set -p fish_complete_path (brew --prefix)/share/fish/completions
+          set -p fish_complete_path (brew --prefix)/share/fish/completions
         end
         if test -d (brew --prefix)/share/fish/vendor_completions.d
-            set -p fish_complete_path (brew --prefix)/share/fish/vendor_completions.d
+          set -p fish_complete_path (brew --prefix)/share/fish/vendor_completions.d
         end
+      end
     end
+    set __brew_instance_initialize 1
+    brew $argv
+  end
 end
+
+alias brew=brew_new_instance
+
+