Consolidate error messages for missing gems, and skip them when running rake gems:* tasks. [rick]

railties/CHANGELOG

@@ -1,5 +1,7 @@
 *SVN*
 
+* Consolidate error messages for missing gems, and skip them when running rake gems:* tasks.  [rick]
+
 * Use a system command to install gems, since GemRunner exits the ruby process.  #210 [Tim Morgan]
 
 *2.1.0 RC1 (May 11th, 2008)*

railties/lib/initializer.rb

@@ -140,6 +140,7 @@ module Rails
       # pick up any gems that plugins depend on
       add_gem_load_paths
       load_gems
+      check_gem_dependencies
       
       load_application_initializers
 
@@ -153,6 +154,7 @@ module Rails
       initialize_routing
 
       # Observers are loaded after plugins in case Observers or observed models are modified by plugins.
+      
       load_observers
     end
 
@@ -241,7 +243,24 @@ module Rails
     end
 
     def load_gems
-      @configuration.gems.each &:load
+      @configuration.gems.each(&:load)
+    end
+
+    def check_gem_dependencies
+      unloaded_gems = @configuration.gems.reject { |g| g.loaded? }
+      if unloaded_gems.size > 0
+        @gems_dependencies_loaded = false
+        # don't print if the gems rake tasks are being run
+        unless $rails_gem_installer
+          puts %{These gems that this application depends on are missing:}
+          unloaded_gems.each do |gem|
+            puts " - #{gem.name}"
+          end
+          puts %{Run "rake gems:install" to install them.}
+        end
+      else
+        @gems_dependencies_loaded = true
+      end
     end
 
     # Loads all plugins in <tt>config.plugin_paths</tt>.  <tt>plugin_paths</tt>
@@ -287,14 +306,10 @@ module Rails
     end
 
     def load_observers
-      if configuration.frameworks.include?(:active_record)
-        if @configuration.gems.any? { |g| !g.loaded? }
-          puts %{Unable to instantiate observers, some gems that this application depends on are missing.  Run "rake gems:install"}
-        else
+      if @gems_dependencies_loaded && configuration.frameworks.include?(:active_record)
         ActiveRecord::Base.instantiate_observers
       end
     end
-    end
 
     # For Ruby 1.8, this initialization sets $KCODE to 'u' to enable the
     # multibyte safe operations. Plugin authors supporting other encodings
@@ -447,16 +462,20 @@ module Rails
 
     # Fires the user-supplied after_initialize block (Configuration#after_initialize)
     def after_initialize
+      if @gems_dependencies_loaded
         configuration.after_initialize_blocks.each do |block|
           block.call
         end
       end
+    end
 
     def load_application_initializers
+      if @gems_dependencies_loaded
         Dir["#{configuration.root_path}/config/initializers/**/*.rb"].sort.each do |initializer|
           load(initializer)
         end
       end
+    end
 
     def prepare_dispatcher
       require 'dispatcher' unless defined?(::Dispatcher)

railties/lib/rails/gem_dependency.rb

@@ -36,7 +36,6 @@ module Rails
       end
       @load_paths_added = true
     rescue Gem::LoadError
-      puts $!.to_s
     end
     
     def dependencies

railties/lib/tasks/gems.rake

@@ -1,5 +1,5 @@
 desc "List the gems that this rails application depends on"
-task :gems => :environment do
+task :gems => 'gems:base' do
   Rails.configuration.gems.each do |gem|
     code = gem.loaded? ? (gem.frozen? ? "F" : "I") : " "
     puts "[#{code}] #{gem.name} #{gem.requirement.to_s}"
@@ -10,8 +10,14 @@ task :gems => :environment do
 end
 
 namespace :gems do
+  task :base do
+    $rails_gem_installer = true
+    Rake::Task[:environment].invoke
+  end
+
   desc "Build any native extensions for unpacked gems"
   task :build do
+    $rails_gem_installer = true
     require 'rails/gem_builder'
     Dir[File.join(RAILS_ROOT, 'vendor', 'gems', '*')].each do |gem_dir|
       spec_file = File.join(gem_dir, '.specification')
@@ -24,14 +30,14 @@ namespace :gems do
   end
   
   desc "Installs all required gems for this application."
-  task :install => :environment do
+  task :install => :base do
     require 'rubygems'
     require 'rubygems/gem_runner'
     Rails.configuration.gems.each { |gem| gem.install unless gem.loaded? }
   end
 
   desc "Unpacks the specified gem into vendor/gems."
-  task :unpack => :environment do
+  task :unpack => :base do
     require 'rubygems'
     require 'rubygems/gem_runner'
     Rails.configuration.gems.each do |gem|