describe_homebrew_ruby: fix regex

`.` need to be escaped, otherwise it will match any character.

Also improve code style for handling string s.

1 files changed, 4 insertions, 3 deletions

diff --git a/Library/Homebrew/extend/os/mac/system_config.rb b/Library/Homebrew/extend/os/mac/system_config.rb
index d3b362aac..c369f38e6 100644
--- a/Library/Homebrew/extend/os/mac/system_config.rb
+++ b/Library/Homebrew/extend/os/mac/system_config.rb
@@ -31,10 +31,11 @@ class SystemConfig
     def describe_homebrew_ruby
       s = describe_homebrew_ruby_version
 
-      if RUBY_PATH.to_s !~ %r{^/System/Library/Frameworks/Ruby.framework/Versions/[12]\.[089]/usr/bin/ruby}
-        s = "#{s} => #{RUBY_PATH}"
+      if RUBY_PATH.to_s !~ %r{^/System/Library/Frameworks/Ruby\.framework/Versions/[12]\.[089]/usr/bin/ruby}
+        "#{s} => #{RUBY_PATH}"
+      else
+        s
       end
-      s
     end
 
     def dump_verbose_config(f = $stdout)