Rails Lighthouse ticket #6530

check_for_method.diff

From 04deb7e63a8e7bcef1c2e47f88cd124325cfc4be Mon Sep 17 00:00:00 2001
From: eianco <eiancoun@gmail.com>
Date: Mon, 7 Mar 2011 23:18:44 -0500
Subject: [PATCH] check for installed commands prior to install gems (git/svn etc)

---
 railties/lib/rails/commands/plugin.rb |   38 ++++++++++++++++++++++++++++----
 1 files changed, 33 insertions(+), 5 deletions(-)

diff --git a/railties/lib/rails/commands/plugin.rb b/railties/lib/rails/commands/plugin.rb
index 048af7c..3df20c2 100644
--- a/railties/lib/rails/commands/plugin.rb
+++ b/railties/lib/rails/commands/plugin.rb
@@ -148,13 +148,17 @@ class Plugin
       method = :git    if git_url?
     end
 
-    uninstall if installed? and options[:force]
+    if send("have_#{method}_cmd?")
+      uninstall if installed? and options[:force]
 
-    unless installed?
-      send("install_using_#{method}", options)
-      run_install_hook
+      unless installed?
+        send("install_using_#{method}", options)
+        run_install_hook
+      else
+        puts "already installed: #{name} (#{uri}).  pass --force to reinstall"
+      end
     else
-      puts "already installed: #{name} (#{uri}).  pass --force to reinstall"
+      puts "missing command line tools (git/svn etc.) required to install plugin"
     end
   end
 
@@ -201,21 +205,37 @@ class Plugin
       uninstall_hook_file = "#{rails_env.root}/vendor/plugins/#{name}/uninstall.rb"
       load uninstall_hook_file if File.exist? uninstall_hook_file
     end
+    
+    def have_export_cmd?
+      is_svn_installed?
+    end
 
     def install_using_export(options = {})
       svn_command :export, options
     end
 
+    def have_checkout_cmd?
+      is_svn_installed?
+    end
+    
     def install_using_checkout(options = {})
       svn_command :checkout, options
     end
 
+    def have_externals_cmd?
+      is_svn_installed?
+    end
+
     def install_using_externals(options = {})
       externals = rails_env.externals
       externals.push([@name, uri])
       rails_env.externals = externals
       install_using_checkout(options)
     end
+    
+    def have_http_cmd?
+      true
+    end
 
     def install_using_http(options = {})
       root = rails_env.root
@@ -228,6 +248,10 @@ class Plugin
       end
     end
 
+    def have_git_cmd?
+      system("git --version")
+    end
+
     def install_using_git(options = {})
       root = rails_env.root
       mkdir_p(install_path = "#{root}/vendor/plugins/#{name}")
@@ -249,6 +273,10 @@ class Plugin
       end
     end
 
+    def is_svn_installed?
+      system("svn --version")
+    end
+
     def svn_command(cmd, options = {})
       root = rails_env.root
       mkdir_p "#{root}/vendor/plugins"
-- 
1.7.1