CI: yard junk (#958)

* run yard-junk during ci

* better indentation

* create test-results/yard

* wat

* waat

* try this

* or this

* does that dir exist

* combine rubocop and yard-junk into single linting task

* dump to stdout

* create linting dir

* test-results does not exist

* persist test-results too

* cant persist HOME

* create test-results subdirs in the container that uses them

* dont care

.circleci/config.yml

@@ -25,6 +25,7 @@ shared_ruby_steps: &shared_ruby_steps
                 curl -L https://codeclimate.com/downloads/test-reporter/test-reporter-latest-linux-amd64 > ./cc-test-reporter
                 chmod +x ./cc-test-reporter
                 ./cc-test-reporter before-build
+    - run: mkdir -p ~/test-results/rspec
     - run:
         name: Run tests
         command: bundle exec rspec --require rspec_junit_formatter --format progress --format RspecJunitFormatter --out ~/test-results/rspec/results.xml
@@ -39,7 +40,7 @@ shared_ruby_steps: &shared_ruby_steps
         paths:
           - ./vendor/bundle
     - store_test_results:
-        path: ~/test-results
+        path: ~/test-results/rspec
     - persist_to_workspace:
         root: .
         paths:
@@ -51,7 +52,6 @@ jobs:
       - image: circleci/ruby:2.6
     steps:
       - checkout
-      - run: "mkdir -p ~/test-results/rspec && mkdir -p ~/test-results/rubocop"
       - persist_to_workspace:
           root: .
           paths:
@@ -63,6 +63,7 @@ jobs:
     steps:
       - attach_workspace:
           at: .
+      - run: mkdir -p ~/test-results/linting
       - run:
           name: RuboCop
           command: |
@@ -71,12 +72,18 @@ jobs:
                     --require rubocop-performance \
                     --format progress \
                     --format RuboCop::Formatter::JUnitFormatter \
-                    --out ~/test-results/rubocop/results.xml
+                    --out ~/test-results/linting/rubocop.xml
+          when: always
+      - run:
+          name: Yard-Junk
+          command: |
+            gem install yard-junk --no-document
+            yard-junk --path lib
           when: always
       - store_test_results:
-          path: ~/test-results
+          path: ~/test-results/linting
       - store_artifacts:
-          path: ~/test-results
+          path: ~/test-results/linting
 
   ruby26:
     docker: