Exclude frequent timeout/hang spec on macOS

* https://github.com/ruby/spec/pull/861/checks?check_run_id=3835708458

security/cve_2010_1330_spec.rb

@@ -1,7 +1,6 @@
 require_relative '../spec_helper'
 
 describe "String#gsub" do
-
   it "resists CVE-2010-1330 by raising an exception on invalid UTF-8 bytes" do
     # This original vulnerability talked about KCODE, which is no longer
     # used. Instead we are forcing encodings here. But I think the idea is the
@@ -17,5 +16,4 @@
       str.gsub(/</, "&lt;")
     }.should raise_error(ArgumentError, /invalid byte sequence in UTF-8/)
   end
-
 end

security/cve_2013_4164_spec.rb

@@ -3,17 +3,13 @@
 require 'json'
 
 describe "String#to_f" do
-
   it "resists CVE-2013-4164 by converting very long Strings to a Float" do
     "1.#{'1'*1000000}".to_f.should be_close(1.1111111111111112, TOLERANCE)
   end
-
 end
 
 describe "JSON.parse" do
-
   it "resists CVE-2013-4164 by converting very long Strings to a Float" do
     JSON.parse("[1.#{'1'*1000000}]").first.should be_close(1.1111111111111112, TOLERANCE)
   end
-
 end

security/cve_2014_8080_spec.rb

@@ -1,6 +1,5 @@
 require_relative '../spec_helper'
 
-
 ruby_version_is ''...'3.0' do
   require 'rexml/document'
 

security/cve_2018_16396_spec.rb

@@ -1,25 +1,21 @@
 require_relative '../spec_helper'
 
 describe "Array#pack" do
-
   ruby_version_is ''...'2.7' do
     it "resists CVE-2018-16396 by tainting output based on input" do
       "aAZBbHhuMmPp".each_char do |f|
         ["123456".taint].pack(f).tainted?.should be_true
       end
     end
   end
-
 end
 
 describe "String#unpack" do
-
   ruby_version_is ''...'2.7' do
     it "resists CVE-2018-16396 by tainting output based on input" do
       "aAZBbHhuMm".each_char do |f|
         "123456".taint.unpack(f).first.tainted?.should be_true
       end
     end
   end
-
 end

security/cve_2018_8778_spec.rb

@@ -1,12 +1,10 @@
 require_relative '../spec_helper'
 
 describe "String#unpack" do
-
   it "resists CVE-2018-8778 by raising an exception when a position indicator is larger than a native integer" do
     pos = (1 << PlatformGuard::POINTER_SIZE) - 99
     -> {
       "0123456789".unpack("@#{pos}C10")
     }.should raise_error(RangeError, /pack length too big/)
   end
-
 end

security/cve_2019_8323_spec.rb

@@ -1,36 +1,38 @@
 require_relative '../spec_helper'
 
-require 'optparse'
+platform_is_not :darwin do # frequent timeout/hang on macOS
+  require 'optparse'
 
-require 'rubygems'
-require 'rubygems/gemcutter_utilities'
+  require 'rubygems'
+  require 'rubygems/gemcutter_utilities'
 
-describe "CVE-2019-8323 is resisted by" do
-  describe "sanitising the body" do
-    it "for success codes" do
-      cutter = Class.new {
-        include Gem::GemcutterUtilities
-      }.new
-      response = Net::HTTPSuccess.new(nil, nil, nil)
-      def response.body
-        "\e]2;nyan\a"
+  describe "CVE-2019-8323 is resisted by" do
+    describe "sanitising the body" do
+      it "for success codes" do
+        cutter = Class.new {
+          include Gem::GemcutterUtilities
+        }.new
+        response = Net::HTTPSuccess.new(nil, nil, nil)
+        def response.body
+          "\e]2;nyan\a"
+        end
+        cutter.should_receive(:say).with(".]2;nyan.")
+        cutter.with_response response
       end
-      cutter.should_receive(:say).with(".]2;nyan.")
-      cutter.with_response response
-    end
 
-    it "for error codes" do
-      cutter = Class.new {
-        include Gem::GemcutterUtilities
-      }.new
-      def cutter.terminate_interaction(n)
-      end
-      response = Net::HTTPNotFound.new(nil, nil, nil)
-      def response.body
-        "\e]2;nyan\a"
+      it "for error codes" do
+        cutter = Class.new {
+          include Gem::GemcutterUtilities
+        }.new
+        def cutter.terminate_interaction(n)
+        end
+        response = Net::HTTPNotFound.new(nil, nil, nil)
+        def response.body
+          "\e]2;nyan\a"
+        end
+        cutter.should_receive(:say).with(".]2;nyan.")
+        cutter.with_response response
       end
-      cutter.should_receive(:say).with(".]2;nyan.")
-      cutter.with_response response
     end
   end
 end

security/cve_2019_8325_spec.rb

@@ -1,9 +1,9 @@
 require_relative '../spec_helper'
 
-require 'rubygems'
-require 'rubygems/command_manager'
-
 platform_is_not :darwin do # frequent timeout/hang on macOS
+  require 'rubygems'
+  require 'rubygems/command_manager'
+
   describe "CVE-2019-8325 is resisted by" do
     describe "sanitising error message components" do
       it "for the 'while executing' message" do