Add use_devtools option for R language to schema

Fixes validation warnings like "unknown key use_devtools".

Author: p00ya

lib/travis/yml.rb

@@ -179,6 +179,7 @@ def r_keys
           warnings_are_errors
           remotes
           repos
+          use_devtools
         )
       end
       memoize :r_keys

lib/travis/yml/schema/def/lang/r.rb

@@ -35,6 +35,7 @@ def define
             map :warnings_are_errors, to: :bool
             map :remotes,             to: :str # this does not seem to be used in travis-build?
             map :repos,               to: :map, strict: false
+            map :use_devtools,        to: :bool
           end
         end
       end

schema.json

@@ -8077,6 +8077,14 @@
                 "r"
               ]
             }
+          },
+          "use_devtools": {
+            "type": "boolean",
+            "only": {
+              "language": [
+                "r"
+              ]
+            }
           }
         },
         "summary": "R language support",
@@ -9178,6 +9186,14 @@
                 "r"
               ]
             }
+          },
+          "use_devtools": {
+            "type": "object",
+            "only": {
+              "language": [
+                "r"
+              ]
+            }
           }
         },
         "normal": true

spec/travis/yml/accept/lang/r_spec.rb

@@ -293,4 +293,14 @@
       it { should_not have_msg }
     end
   end
+
+  describe 'use_devtools' do
+    describe 'given a bool' do
+      yaml %(
+        use_devtools: true
+      )
+      it { should serialize_to use_devtools: true }
+      it { should_not have_msg }
+    end
+  end
 end

spec/travis/yml/schema/accept/lang/r_spec.rb

@@ -172,5 +172,13 @@
       it { should_not validate language: {:foo=>'foo'} }
       it { should_not validate language: [{:foo=>'foo'}] }
     end
+    describe 'use_devtools' do
+      it { should validate language: :r }
+      it { should_not validate language: 1 }
+      it { should_not validate language: true }
+      it { should_not validate language: [:r] }
+      it { should_not validate language: {:foo=>'foo'} }
+      it { should_not validate language: [{:foo=>'foo'}] }
+    end
   end
 end

spec/travis/yml/schema/def/lang/r_spec.rb

@@ -192,6 +192,14 @@
                 'r'
               ]
             }
+          },
+          use_devtools: {
+            type: :boolean,
+            only: {
+              language: [
+                'r'
+              ]
+            }
           }
         },
         normal: true