tune syntax error message output, handle invalid plugin names that ar…

…en't syntax errors

lib/ohai/dsl/plugin.rb

@@ -27,6 +27,10 @@ module Ohai
 
   # For plugin namespacing
   module NamedPlugin
+    def self.valid_name?(name)
+      name.is_a?(Symbol) && name.to_s.match(/^[^A-Z]|_/).nil?
+    end
+
     # dealing with ruby 1.8
     if Module.method(:const_defined?).arity == 1
       def self.strict_const_defined?(const)
@@ -40,6 +44,8 @@ def self.strict_const_defined?(const)
   end
 
   def self.plugin(name, &block)
+    raise Ohai::Exceptions::InvalidPluginName, "#{name} is not a valid plugin name. A valid plugin name is a symbol which begins with a capital letter and contains no underscores" unless NamedPlugin.valid_name?(name)
+
     plugin = nil
 
     if NamedPlugin.strict_const_defined?(name)

lib/ohai/exception.rb

@@ -19,6 +19,7 @@
 module Ohai
   module Exceptions
     class Exec < RuntimeError; end
+    class InvalidPluginName < Exception; end
     class IllegalPluginDefinition < Exception; end
     class AttributeNotFound < Exception; end
     class ProviderNotFound < Exception; end

lib/ohai/loader.rb

@@ -74,6 +74,8 @@ def load_v7_plugin(contents, plugin_path)
         plugin = klass.new(@controller.data) unless klass.nil?
       rescue SystemExit, Interrupt
         raise
+      rescue Ohai::Exceptions::InvalidPluginName => e
+        Ohai::Log.warn("Invalid name for plugin at #{plugin_path}: #{e.message}")
       rescue Ohai::Exceptions::IllegalPluginDefinition => e 
         Ohai::Log.warn("Plugin at #{plugin_path} is not properly defined: #{e.inspect}")
       rescue NoMethodError => e

spec/unit/dsl/plugin_spec.rb

@@ -91,6 +91,26 @@
     @name = :Test
   end
 
+  describe "when the plugin is named incorrectly" do
+    context "because the plugin name doesn't start with a capital letter" do
+      it "should raise an Ohai::Exceptions::InvalidPluginName exception" do
+        expect{ Ohai.plugin(:badName) { } }.to raise_error(Ohai::Exceptions::InvalidPluginName, /badName is not a valid plugin name/)
+      end
+    end
+
+    context "because the plugin name contains an underscore" do
+      it "should raise an Ohai::Exceptions::InvalidPluginName exception" do
+        expect{ Ohai.plugin(:Bad_Name) { } }.to raise_error(Ohai::Exceptions::InvalidPluginName, /Bad_Name is not a valid plugin name/)
+      end
+    end
+
+    context "because the plugin name isn't a symbol" do
+      it "should raise an Ohai::Exceptions::InvalidPluginName exception" do
+        expect{ Ohai.plugin(1138) { } }.to raise_error(Ohai::Exceptions::InvalidPluginName, /1138 is not a valid plugin name/)
+      end
+    end
+  end
+
   describe "#version" do
     it "should save the plugin version as :version7" do
       plugin = Ohai.plugin(@name) { }

spec/unit/loader_spec.rb

@@ -100,6 +100,19 @@
 Ohai.plugin(:1nval!d) do
   provides "not_a_symbol"
 end
+EOF
+
+    with_plugin("no_end.rb", <<EOF)
+Ohai.plugin(:NoEnd) do
+  provides "fish_oil"
+  collect_data do
+end
+EOF
+
+    with_plugin("bad_name.rb", <<EOF)
+Ohai.plugin(:you_give_plugins_a_bad_name) do
+  provides "that/one/song"
+end
 EOF
 
     describe "load_plugin() method" do
@@ -168,6 +181,17 @@
           expect{ @loader.load_plugin(path_to("no_end.rb")) }.not_to raise_error
         end
       end
+
+      describe "when the plugin has an invalid name" do
+        it "should log an invalid plugin name warning" do
+          Ohai::Log.should_receive(:warn).with(/Invalid name for plugin/)
+          @loader.load_plugin(path_to("bad_name.rb"))
+        end
+
+        it "should not raise an error" do
+          expect{ @loader.load_plugin(path_to("bad_name.rb")) }.not_to raise_error
+        end
+      end
     end
   end
 end