[rubygems/rubygems] Improve insecure gem overwrite message

https://github.com/rubygems/rubygems/commit/7c71dac22e

lib/bundler/errors.rb

@@ -217,15 +217,15 @@ module Bundler
   end
 
   class InsecureInstallPathError < BundlerError
-    def initialize(path)
+    def initialize(name, path)
+      @name = name
       @path = path
     end
 
     def message
-      "The installation path is insecure. Bundler cannot continue.\n" \
-      "#{@path} is world-writable (without sticky bit).\n" \
-      "Bundler cannot safely replace gems in world-writeable directories due to potential vulnerabilities.\n" \
-      "Please change the permissions of this directory or choose a different install path."
+      "Bundler cannot reinstall #{@name} because there's a previous installation of it at #{@path} that is unsafe to remove.\n" \
+      "The parent of #{@path} is world-writable and does not have the sticky bit set, making it insecure to remove due to potential vulnerabilities.\n" \
+      "Please change the permissions of #{File.dirname(@path)} or choose a different install path."
     end
 
     status_code(38)

lib/bundler/rubygems_gem_installer.rb

@@ -155,7 +155,7 @@ module Bundler
       parent_st = File.stat(parent)
 
       if parent_st.world_writable? && !parent_st.sticky?
-        raise InsecureInstallPathError.new(parent)
+        raise InsecureInstallPathError.new(spec.full_name, dir)
       end
 
       begin

spec/bundler/commands/install_spec.rb

@@ -1055,7 +1055,7 @@ RSpec.describe "bundle install with gem sources" do
 
       bundle "install --redownload", raise_on_error: false
 
-      expect(err).to include("The installation path is insecure. Bundler cannot continue.")
+      expect(err).to include("Bundler cannot reinstall foo-1.0.0 because there's a previous installation of it at #{gems_path}/foo-1.0.0 that is unsafe to remove")
     end
   end