From 9d287483b77c112b40fe0546d4d65cdd27c23cb0 Mon Sep 17 00:00:00 2001
From: Gautham Goli <goligautham@gmail.com>
Date: Fri, 18 Jan 2019 22:17:46 +0530
Subject: [PATCH] cat: Use CLI::Parser to parse args

---
 Library/Homebrew/cmd/cat.rb            | 15 ++++++++++++++-
 Library/Homebrew/test/cmd/help_spec.rb |  4 ++--
 2 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/Library/Homebrew/cmd/cat.rb b/Library/Homebrew/cmd/cat.rb
index 7439869d30..5cf7077cc9 100644
--- a/Library/Homebrew/cmd/cat.rb
+++ b/Library/Homebrew/cmd/cat.rb
@@ -1,16 +1,29 @@
 #:  * `cat` <formula>:
 #:    Display the source to <formula>.
 
+require "cli_parser"
+
 module Homebrew
   module_function
 
+  def cat_args
+    Homebrew::CLI::Parser.new do
+      usage_banner <<~EOS
+        `cat` <formula>
+
+        Display the source to <formula>.
+      EOS
+    end
+  end
+
   def cat
+    cat_args.parse
     # do not "fix" this to support multiple arguments, the output would be
     # unparsable, if the user wants to cat multiple formula they can call
     # brew cat multiple times.
     formulae = ARGV.formulae
     raise FormulaUnspecifiedError if formulae.empty?
-    raise "`brew cat` doesn't support multiple arguments" if formulae.size > 1
+    raise "`brew cat` doesn't support multiple arguments" if args.remaining.size > 1
 
     cd HOMEBREW_REPOSITORY
     exec "cat", formulae.first.path, *ARGV.options_only
diff --git a/Library/Homebrew/test/cmd/help_spec.rb b/Library/Homebrew/test/cmd/help_spec.rb
index e3460dec0f..ab80b69f01 100644
--- a/Library/Homebrew/test/cmd/help_spec.rb
+++ b/Library/Homebrew/test/cmd/help_spec.rb
@@ -14,7 +14,7 @@ describe "brew", :integration_test do
 
     it "prints help for a documented Ruby command" do
       expect { brew "help", "cat" }
-        .to output(/^brew cat/).to_stdout
+        .to output(/^Usage: brew cat/).to_stdout
         .and be_a_success
     end
 
@@ -40,7 +40,7 @@ describe "brew", :integration_test do
   describe "cat" do
     it "prints help when no argument is given" do
       expect { brew "cat" }
-        .to output(/^brew cat/).to_stderr
+        .to output(/^Usage: brew cat/).to_stderr
         .and be_a_failure
     end
   end