add some error checking around `Kernel.system`

crew

@@ -148,18 +148,22 @@ def download
 end
 
 def resolveDependenciesAndInstall
-  origin = @pkg.name
+  begin
+    origin = @pkg.name
 
-  resolveDependencies
+    resolveDependencies
   
-  search origin
-  install
-
-  #cleanup
-  unless ARGV[2] == 'keep'
-    Dir.chdir CREW_BREW_DIR do
-      system "rm -rf *"
-      system "mkdir dest" #this is a little ugly, feel free to find a better way
+    search origin
+    install
+  rescue InstallError => e 
+    puts "install error: #{e.to_s}"
+  ensure
+    #cleanup
+    unless ARGV[2] == 'keep'
+      Dir.chdir CREW_BREW_DIR do
+        system "rm -rf *"
+        system "mkdir dest" #this is a little ugly, feel free to find a better way
+      end
     end
   end
 end
@@ -183,7 +187,7 @@ def resolveDependencies
   return if @dependencies.empty?
 
   puts "Following packages also need to be installed: "
-  @dependencies.flatten!.each do |dep|
+  @dependencies.flatten!.uniq!.each do |dep|
     print dep + " "
   end
   puts ""

lib/package.rb

@@ -26,4 +26,10 @@ class Package
   def self.build
     
   end
+
+  def self.system(*args)
+    Kernel.system(*args)
+    exitstatus = $?.exitstatus
+    raise InstallError.new("`#{args.join(" ")}` exited with #{exitstatus}") unless exitstatus == 0
+  end
 end

lib/package_helpers.rb

+class InstallError < RuntimeError; end
+
 def property(*properties)
   properties.each do |prop|
     self.class_eval("def self.#{prop}(#{prop} = nil); @#{prop} = #{prop} if #{prop}; @#{prop}; end")