(PUP-11315) Allow resource attributes named "plan" and "apply"

Previously, using either of these keywords as resource attribute names
within an apply() block in a plan would fail. That happened because they
weren't included in the `keyword` rule. This was only a problem when
running in a plan, because those keywords only exist when the `tasks`
setting is set. In normal Puppet operation, they aren't lexed as special
tokens at all, so they didn't need to be in the `keyword` rule to
function properly.

We now add them to the `keyword` rule regardless of whether they are
actually lexed as keywords, which works fine in both cases.

Author: nicklewis

lib/puppet/pops/parser/egrammar.ra

@@ -919,6 +919,8 @@ keyword
   | CONSUMES
   | PRODUCES
   | SITE
+  | PLAN
+  | APPLY
 
 nil
   : { result = nil}

spec/unit/pops/parser/parse_containers_spec.rb

@@ -106,7 +106,7 @@
 
     context 'it should allow keywords as attribute names' do
       ['and', 'case', 'class', 'default', 'define', 'else', 'elsif', 'if', 'in', 'inherits', 'node', 'or',
-        'undef', 'unless', 'type', 'attr', 'function', 'private'].each do |keyword|
+        'undef', 'unless', 'type', 'attr', 'function', 'private', 'plan', 'apply'].each do |keyword|
         it "such as #{keyword}" do
           expect { parse("class x ($#{keyword}){} class { x: #{keyword} => 1 }") }.to_not raise_error
         end
@@ -178,7 +178,7 @@
 
     context 'it should allow keywords as attribute names' do
       ['and', 'case', 'class', 'default', 'define', 'else', 'elsif', 'if', 'in', 'inherits', 'node', 'or',
-        'undef', 'unless', 'type', 'attr', 'function', 'private'].each do |keyword|
+        'undef', 'unless', 'type', 'attr', 'function', 'private', 'plan', 'apply'].each do |keyword|
         it "such as #{keyword}" do
           expect {parse("define x ($#{keyword}){} x { y: #{keyword} => 1 }")}.to_not raise_error
         end

spec/unit/pops/validator/validator_spec.rb

@@ -432,6 +432,11 @@ def with_environment(environment, env_params = {})
         expect(acceptor.error_count).to eql(0)
       end
 
+      it 'allows apply to be used as a resource attribute name' do
+        acceptor = validate(parse('apply("foo.example.com") { sometype { "resourcetitle": apply => "applyvalue" } }'))
+        expect(acceptor.error_count).to eql(0)
+      end
+
       it 'accepts multiple arguments' do
         acceptor = validate(parse('apply(["foo.example.com"], { "other" => "args" }) { }'))
         expect(acceptor.error_count).to eql(0)