add build_deps parameter to optionally skip the package setup

resolves #44
resolves #43
references #41

README.md

@@ -94,6 +94,18 @@ class { '::composer':
 }
 ```
 
+### Repairing duplicated packages
+
+As described in [#44](https://github.com/willdurand/puppet-composer/issues/44) in several cases it's possible that the catalogue crashes because of duplicate package declarations.
+
+In order to skip the installation of `wget` from this module, you can use the `build_deps` argument:
+
+``` puppet
+class { '::composer':
+  build_deps => false,
+}
+```
+
 ### Global composer configs
 
 One feature of composer are [global configuration parameters](https://getcomposer.org/doc/06-config.md#config).

manifests/init.pp

@@ -42,15 +42,20 @@
   $version          = undef,
   $group            = undef,
   $download_timeout = '0',
+  $build_deps       = true,
 ) {
   validate_string($target_dir)
   validate_string($command_name)
   validate_string($user)
   validate_bool($auto_update)
   validate_string($version)
   validate_string($group)
+  validate_bool($build_deps)
+
+  if $build_deps {
+    ensure_packages(['wget'])
+  }
 
-  ensure_packages(['wget'])
   include composer::params
 
   $composer_target_dir = $target_dir ? {

spec/classes/composer_spec.rb

@@ -110,4 +110,10 @@
       .with_timeout('25') \
     }
   end
+
+  describe 'with build_deps=false' do
+    let(:params) {{ :build_deps => false }}
+
+    it { should_not contain_package('wget') }
+  end
 end