[rubygems/rubygems] Simplify nested require exceptions

https://github.com/rubygems/rubygems/commit/7fbef2f0e3

lib/rubygems/core_ext/kernel_require.rb

@@ -156,8 +156,7 @@ module Kernel
     RUBYGEMS_ACTIVATION_MONITOR.enter
 
     begin
-      if load_error.message.start_with?("Could not find") or
+      if load_error.message.end_with?(path) and Gem.try_activate(path)
-          (load_error.message.end_with?(path) and Gem.try_activate(path))
         require_again = true
       end
     ensure

test/rubygems/test_kernel.rb

@@ -91,6 +91,25 @@ class TestKernel < Gem::TestCase
     refute $:.any? { |p| %r{a-1/bin} =~ p }
   end
 
+  def test_gem_failing_inside_require_doesnt_cause_double_exceptions
+    File.write("activate.rb", "gem('a', '= 999')\n")
+
+    require "open3"
+
+    output, _ = Open3.capture2e(
+      { "GEM_HOME" => Gem.paths.home },
+      Gem.ruby,
+      "-I",
+      File.expand_path("../../lib", __dir__),
+      "-r",
+      "./activate.rb"
+    )
+
+    load_errors = output.split("\n").select { |line| line.include?("Could not find")}
+
+    assert_equal 1, load_errors.size
+  end
+
   def test_gem_bundler
     quick_gem 'bundler', '1'
     quick_gem 'bundler', '2.a'