[4638] Cleanup of plurals and inheritance relationships in AST

Changed the grammar so that the following "plural" constructs always
parse as an ASTArray:

- funcvalues
- rvalues
- resourceinstances
- anyparams
- params
- caseopts
- casevalues

And the following "singluar" construct never parses as an ASTArray:

- statement

The previous behavior was for these constructs to parse as a scalar
when they represented a single item and an ASTArray when they
contained zero or multiple items.  ("Statement" could sometimes
represent a single item because a single resource declaration could
represent multiple resources).  This complicated other grammar rules
and caused ambiguous handling of nested arrays.

Also made these changes to the AST class hierarchy:

- ResourceInstance no longer derives from ASTArray.  This relationship
  was not meaningful because a ResourceInstance is a (title,
  parameters) pair, not an array, and it produced complications when
  we wanted to represent an array of ResourceInstance objects.

- Resource no longer derives from ResourceReference.  No significant
  functionality was being inherited and the relationship doesn't make
  sense in an AST context.

- ResourceOverride no longer derives from Resource.  No significant
  functionality was being inherited and the relationship doesn't make
  sense in an AST context.

- Resource can now represent a compound resource instance such as
  "notify { foo: ; bar: }".  This saves the parser from having to
  use represent a statement as an array of objects.

- ASTArray's evaluate method never flattens out arrays of arrays.

1 files changed, 5 insertions, 8 deletions

diff --git a/test/lib/puppettest/parsertesting.rb b/test/lib/puppettest/parsertesting.rb
index bd04c1ec5..411bad37a 100644
--- a/test/lib/puppettest/parsertesting.rb
+++ b/test/lib/puppettest/parsertesting.rb
@@ -94,16 +94,15 @@ module PuppetTest::ParserTesting
 
   def resourcedef(type, title, params)
     title = stringobj(title) unless title.is_a?(AST)
+    instance = AST::ResourceInstance.new(:title => title, :parameters => resourceparams(params))
     assert_nothing_raised("Could not create #{type} #{title}") {
 
       return AST::Resource.new(
 
         :file => __FILE__,
         :line => __LINE__,
-        :title => title,
         :type => type,
-
-        :parameters => resourceinst(params)
+        :instances => AST::ASTArray.new(:children => [instance])
       )
     }
   end
@@ -122,9 +121,7 @@ module PuppetTest::ParserTesting
         :file => __FILE__,
         :line => __LINE__,
         :object => resourceref(type, title),
-
-        :type => type,
-        :parameters => resourceinst(params)
+        :parameters => resourceparams(params)
       )
     }
   end
@@ -197,13 +194,13 @@ module PuppetTest::ParserTesting
     }
   end
 
-  def resourceinst(hash)
+  def resourceparams(hash)
     assert_nothing_raised("Could not create resource instance") {
       params = hash.collect { |param, value|
       resourceparam(param, value)
     }
 
-      return AST::ResourceInstance.new(
+      return AST::ASTArray.new(
 
         :file => tempfile,