make app creation more object oriented

split up validation of Apps into three separate concerns:

1. is it a valid dir name?
2. does the user have rx to it?
3. is there a manifest for it the user can read?

for the factory methods return all apps where 1 and 2 or 1 and 3 are true

lib/awesim/app.rb

@@ -4,13 +4,16 @@ module AweSim
 
     PROTECTED_NAMES = ["shared_apps", "cgi-bin", "tmp"]
 
+    # FIXME: still returns nil sometimes yuck
     def self.at(path: path)
-      self.new(workdir: path) if self.valid_app_dir?(path)
+      app = self.new(workdir: path)
+      app if app.valid_dir? && (app.accessible? || app.manifest.exist?)
     end
 
     def self.all_at(path: path)
       Dir.glob("#{path}/**").sort.reduce([]) do |apps, appdir|
-        apps << self.new(workdir: appdir) if self.valid_app_dir?(appdir)
+        app = self.at(path: appdir)
+        apps << app unless app.nil?
         apps
       end
     end
@@ -25,6 +28,19 @@ module AweSim
       dir.executable? && dir.readable?
     end
 
+    # FIXME: should we be making clear which methods of App
+    # require accessible? true i.e. rx access to 
+    def accessible?
+      workdir.executable? && workdir.readable?
+    end
+    alias_method :rx?, :accessible?
+
+    def valid_dir?
+      (workdir.directory? &&
+       ! self.class::PROTECTED_NAMES.include?(workdir.basename.to_s) &&
+       workdir.extname != ".git")
+    end
+
     def initialize(workdir: nil)
       # TODO: add gitdir and other properties
       @workdir = Pathname.new(workdir.to_s)

test/test_app_manifest.rb

@@ -55,10 +55,8 @@ documentation: |
     add_manifest(@tmpdir.join("app_norx.yml"))
 
     assert_valid_manifest app.manifest
-    # assert ! app.accessible?, "app should indicate its not accesible"
-    # assert app.manifest.avail?, "manifest#avail? should return true" # better than exist?
-
-    # TODO: way to verify which manifest was read is to modify the parent yaml
+    assert ! app.accessible?, "app should indicate its not accesible"
+    assert app.valid_dir?, "app is valid directory name"
   end
 
   # TODO: cfs.yml, cfs/manifest.yml, and cfs rx: read manifest.yml