Merge pull request #2706 from rolandwalker/install_suggest

suggest replacements on "brew cask install" fail

lib/cask/cli/install.rb

@@ -5,8 +5,19 @@ def self.run(*args)
     force = args.include? '--force'
     cask_names.each do |cask_name|
       odebug "Installing Cask #{cask_name}"
-      cask = Cask.load(cask_name)
-      Cask::Installer.new(cask).install(force)
+      begin
+        cask = Cask.load(cask_name)
+        Cask::Installer.new(cask).install(force)
+      rescue CaskUnavailableError => e
+        exact_match, partial_matches, search_term = Cask::CLI::Search.search(cask_name)
+        errmsg = "#{cask_name}"
+        if exact_match
+          errmsg.concat(". Did you mean:\n#{exact_match}")
+        elsif !partial_matches.empty?
+          errmsg.concat(". Did you mean one of:\n#{stringify_columns(partial_matches.take(20))}\n")
+        end
+        raise CaskUnavailableError.new(errmsg)
+      end
     end
   end
 

lib/cask/utils.rb

@@ -2,6 +2,7 @@
 # see Homebrew Library/Homebrew/utils.rb
 
 require 'yaml'
+require 'open3'
 
 # monkeypatch Tty
 class Tty
@@ -66,3 +67,28 @@ def odumpcask cask
     end
   end
 end
+
+# from Homebrew puts_columns
+def stringify_columns items, star_items=[]
+  return if items.empty?
+
+  if star_items && star_items.any?
+    items = items.map{|item| star_items.include?(item) ? "#{item}*" : item}
+  end
+
+  if $stdout.tty?
+    # determine the best width to display for different console sizes
+    console_width = `/bin/stty size`.chomp.split(" ").last.to_i
+    console_width = 80 if console_width <= 0
+  else
+    console_width = 80
+  end
+  longest = items.sort_by { |item| item.length }.last
+  optimal_col_width = (console_width.to_f / (longest.length + 2).to_f).floor
+  cols = optimal_col_width > 1 ? optimal_col_width : 1
+  Open3.popen3('/usr/bin/pr', "-#{cols}", '-t', "-w#{console_width}") do |stdin, stdout, stderr|
+    stdin.puts(items)
+    stdin.close
+    stdout.read
+  end
+end

test/cask/cli/install_test.rb

@@ -42,6 +42,20 @@
     }.must_raise CaskUnavailableError
   end
 
+  it "returns a suggestion for a misspelled Cask" do
+    e = lambda {
+      Cask::CLI::Install.run('googlechrome')
+    }.must_raise CaskUnavailableError
+    e.message.must_equal "No available cask for googlechrome\. Did you mean:\ngoogle-chrome"
+  end
+
+  it "returns multiple suggestions for a Cask fragment" do
+    e = lambda {
+      Cask::CLI::Install.run('google')
+    }.must_raise CaskUnavailableError
+    e.message.must_match %r{^No available cask for google\. Did you mean one of:\ngoogle}
+  end
+
   it "raises an exception when no cask is specified" do
     lambda {
       Cask::CLI::Install.run