utils: fix Rubocop warnings.

Library/Homebrew/utils.rb

@@ -138,12 +138,11 @@ def odeprecated(method, replacement = nil, options = {})
   backtrace = options.fetch(:caller, caller)
   tap_message = nil
   caller_message = backtrace.detect do |line|
-    if line =~ %r{^#{Regexp.escape HOMEBREW_LIBRARY}/Taps/([^/]+/[^/]+)/}
+    next unless line =~ %r{^#{Regexp.escape HOMEBREW_LIBRARY}/Taps/([^/]+/[^/]+)/}
     tap = Tap.fetch $1
     tap_message = "\nPlease report this to the #{tap} tap!"
     true
   end
-  end
   caller_message ||= backtrace.detect do |line|
     !line.start_with?("#{HOMEBREW_LIBRARY_PATH}/compat/")
   end
@@ -170,7 +169,7 @@ end
 
 def pretty_installed(f)
   if !$stdout.tty?
-    "#{f}"
+    f.to_s
   elsif Emoji.enabled?
     "#{Tty.highlight}#{f} #{Tty.green}#{Emoji.tick}#{Tty.reset}"
   else
@@ -180,7 +179,7 @@ end
 
 def pretty_uninstalled(f)
   if !$stdout.tty?
-    "#{f}"
+    f.to_s
   elsif Emoji.enabled?
     "#{f} #{Tty.red}#{Emoji.cross}#{Tty.reset}"
   else
@@ -196,7 +195,7 @@ def pretty_duration(s)
     m = s / 60
     s %= 60
     res = "#{m} minute#{plural m}"
-    return res if s == 0
+    return res if s.zero?
     res << " "
   end
 
@@ -204,7 +203,7 @@ def pretty_duration(s)
 end
 
 def plural(n, s = "s")
-  (n == 1) ? "" : s
+  n == 1 ? "" : s
 end
 
 def interactive_shell(f = nil)
@@ -233,7 +232,11 @@ module Homebrew
     pid = fork do
       yield if block_given?
       args.collect!(&:to_s)
-      exec(cmd, *args) rescue nil
+      begin
+        exec(cmd, *args)
+      rescue
+        nil
+      end
       exit! 1 # never gets here unless exec failed
     end
     Process.wait(pid)
@@ -291,7 +294,7 @@ module Homebrew
       rescue Gem::SystemExitException => e
         exit_code = e.exit_code
       end
-      odie "Failed to install/update the '#{name}' gem." if exit_code != 0
+      odie "Failed to install/update the '#{name}' gem." if exit_code.nonzero?
     end
 
     unless which executable
@@ -542,10 +545,10 @@ def disk_usage_readable(size_in_bytes)
   end
 
   # avoid trailing zero after decimal point
-  if (size * 10).to_i % 10 == 0
+  if ((size * 10).to_i % 10).zero?
     "#{size.to_i}#{unit}"
   else
-    "#{"%.1f" % size}#{unit}"
+    "#{format("%.1f", size)}#{unit}"
   end
 end
 
@@ -572,10 +575,10 @@ def truncate_text_to_approximate_size(s, max_bytes, options = {})
   glue_bytes = glue.encode("BINARY")
   n_front_bytes = (max_bytes_in * front_weight).floor
   n_back_bytes = max_bytes_in - n_front_bytes
-  if n_front_bytes == 0
+  if n_front_bytes.zero?
     front = bytes[1..0]
     back = bytes[-max_bytes_in..-1]
-  elsif n_back_bytes == 0
+  elsif n_back_bytes.zero?
     front = bytes[0..(max_bytes_in - 1)]
     back = bytes[1..0]
   else