Allow configuration to be specified by packs.yml (#6)

* Change tests to match new desired behavior

* Fix broken tests

* bump version

* allow configuration to be updated via ruby

Author: Alex Evanczuk

Gemfile.lock

@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    packs (0.0.2)
+    packs (0.0.3)
       sorbet-runtime
 
 GEM

lib/packs.rb

@@ -3,7 +3,6 @@
 require 'yaml'
 require 'sorbet-runtime'
 require 'packs/pack'
-require 'packs/configuration'
 require 'packs/private'
 
 module Packs
@@ -38,6 +37,17 @@ def bust_cache!
       @for_file = nil
     end
 
+    sig { returns(Private::Configuration) }
+    def config
+      @config = T.let(@config, T.nilable(Private::Configuration))
+      @config ||= Private::Configuration.fetch
+    end
+
+    sig { params(blk: T.proc.params(arg0: Private::Configuration).void).void }
+    def configure(&blk)
+      yield(config)
+    end
+
     private
 
     sig { returns(T::Hash[String, Pack]) }
@@ -56,12 +66,9 @@ def packs_by_name
 
     sig { returns(T::Array[Pathname]) }
     def package_glob_patterns
-      config.roots.flat_map do |root|
-        absolute_root = Private.root.join(root)
-        [
-          *absolute_root.glob("*/#{PACKAGE_FILE}"),
-          *absolute_root.glob("*/*/#{PACKAGE_FILE}")
-        ]
+      absolute_root = Private.root
+      config.pack_paths.flat_map do |pack_path|
+        Pathname.glob(absolute_root.join(pack_path).join(PACKAGE_FILE))
       end
     end
   end

lib/packs/configuration.rb

@@ -1,5 +1,7 @@
 # typed: strict
 
+require 'packs/private/configuration'
+
 module Packs
   module Private
     extend T::Sig

lib/packs/private.rb

@@ -0,0 +1,35 @@
+# typed: strict
+
+module Packs
+  module Private
+    class Configuration < T::Struct
+      extend T::Sig
+      DEFAULT_PACK_PATHS = T.let([
+        'packs/*',
+        'packs/*/*',
+      ], T::Array[String])
+
+      prop :pack_paths, T::Array[String]
+
+      sig { returns(Configuration) }
+      def self.fetch
+        configuration_path = Pathname.new('packs.yml')
+        config_hash = configuration_path.exist? ? YAML.load_file('packs.yml') : {}
+
+        new(
+          pack_paths: pack_paths(config_hash),
+        )
+      end
+
+      sig { params(config_hash: T::Hash[T.untyped, T.untyped]).returns(T::Array[String]) }
+      def self.pack_paths(config_hash)
+        specified_pack_paths = config_hash['pack_paths']
+        if specified_pack_paths.nil?
+          DEFAULT_PACK_PATHS.dup
+        else
+          Array(specified_pack_paths)
+        end
+      end
+    end
+  end
+end

lib/packs/private/configuration.rb

@@ -1,6 +1,6 @@
 Gem::Specification.new do |spec|
   spec.name          = 'packs'
-  spec.version       = '0.0.2'
+  spec.version       = '0.0.3'
   spec.authors       = ['Gusto Engineers']
   spec.email         = ['dev@gusto.com']
   spec.summary       = 'Packs are the specification for gradual modularization in the `rubyatscale` ecosystem.'

packs.gemspec

@@ -20,11 +20,25 @@
     end
 
     context 'in an app with a differently configured root' do
+      before do
+        write_file('packs/my_pack/package.yml')
+        write_file('components/my_pack/package.yml')
+        write_file('packs.yml', <<~YML)
+        pack_paths:
+          - packs/*
+          - components/*
+        YML
+      end
+
+      it { expect(Packs.all.count).to eq 2 }
+    end
+
+    context 'in an app with a differently configured root configured via ruby' do
       before do
         write_file('packs/my_pack/package.yml')
         write_file('components/my_pack/package.yml')
         Packs.configure do |config|
-          config.roots = %w[components packs]
+          config.pack_paths = ['packs/*', 'components/*']
         end
       end
 
@@ -55,9 +69,11 @@
       before do
         write_file('packs/my_pack/package.yml')
         write_file('components/my_pack/package.yml')
-        Packs.configure do |config|
-          config.roots = %w[components packs]
-        end
+        write_file('packs.yml', <<~YML)
+        pack_paths:
+          - packs/*
+          - components/*
+        YML
       end
 
       it { expect(Packs.find('packs/my_pack').name).to eq 'packs/my_pack' }

spec/packs_spec.rb

@@ -17,9 +17,6 @@
 
   config.before do
     Packs.bust_cache!
-    Packs.configure do |packs_config|
-      packs_config.roots = ['packs']
-    end
   end
 
   config.around do |example|