ci: track coverage with codecov.io instead of codeclimate.com.

Comparison:

* Codecov has a simpler integration and a better UI.
* Codeclimate tracks both linter warnings (Rubocop, ESLint) and code
  coverage, but its UI for code coverage is worse than Codecov's.
* Codeclimate doesn't support Simplecov 0.18 because Codeclimate doesn't
  support 0.18's new coverage format yet.

.codecov.yml

@@ -0,0 +1 @@
+comment: false

.github/workflows/test.yaml

@@ -34,10 +34,7 @@ jobs:
       RUBYOPT: -W0 # silence ruby warnings
       VIPS_WARNING: 0 # silence libvips warnings
 
-      # Code Climate configuration. https://docs.codeclimate.com/docs/finding-your-test-coverage-token
+      CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}
-      CC_TEST_REPORTER_ID: ${{ secrets.CC_TEST_REPORTER_ID }}
-      GIT_COMMIT_SHA: ${{ github.sha }}
-      GIT_BRANCH: ${{ github.ref }}
 
       DATABASE_URL: postgresql://danbooru:danbooru@postgres/danbooru
       ARCHIVE_DATABASE_URL: postgresql://danbooru:danbooru@postgres/danbooru
@@ -74,7 +71,7 @@ jobs:
     - name: Install OS dependencies
       run: |
         apt-get update
-        apt-get -y install --no-install-recommends build-essential ruby ruby-dev ruby-bundler git nodejs yarnpkg webpack ffmpeg mkvtoolnix libvips-dev libxml2-dev libxslt-dev zlib1g-dev postgresql-server-dev-all wget
+        apt-get -y install --no-install-recommends build-essential ruby ruby-dev ruby-bundler git nodejs yarnpkg webpack ffmpeg mkvtoolnix libvips-dev libxml2-dev libxslt-dev zlib1g-dev postgresql-server-dev-all wget curl
         ln -sf /usr/bin/yarnpkg /usr/bin/yarn
 
     - name: Install Ruby dependencies
@@ -86,23 +83,5 @@ jobs:
     - name: Prepare database
       run: config/docker/prepare-tests.sh
 
-    # https://docs.codeclimate.com/docs/configuring-test-coverage
-    - name: Prepare test coverage for Code Climate
-      run: |
-        wget https://codeclimate.com/downloads/test-reporter/test-reporter-latest-linux-amd64
-        chmod +x test-reporter-latest-linux-amd64
-        ./test-reporter-latest-linux-amd64 before-build
-
     - name: Run tests
       run: bin/rails test
-
-    - name: Upload test coverage to Code Climate
-      if: ${{ !cancelled() }}
-      run: GIT_COMMITTED_AT="$(date -u +%s)" ./test-reporter-latest-linux-amd64 after-build --debug
-
-    # https://docs.codecov.io/docs
-    - name: Upload test coverage to Codecov.io
-      if: ${{ !cancelled() }}
-      uses: codecov/codecov-action@v1
-      with:
-        token: ${{ secrets.CODECOV_TOKEN }}

.simplecov

@@ -5,4 +5,10 @@ SimpleCov.start "rails" do
   #minimum_coverage line: 85, branch: 75
   #minimum_coverage_by_file 50
   #coverage_dir "tmp/coverage"
+
+  # https://github.com/codecov/codecov-ruby#submit-only-in-ci-example
+  if ENV["CODECOV_TOKEN"]
+    require "codecov"
+    SimpleCov.formatter = SimpleCov::Formatter::Codecov
+  end
 end

Gemfile

@@ -86,4 +86,5 @@ group :test do
   gem "mock_redis"
   gem "capybara"
   gem "selenium-webdriver"
+  gem "codecov", require: false
 end

Gemfile.lock

@@ -120,6 +120,10 @@ GEM
       xpath (~> 3.2)
     childprocess (3.0.0)
     chronic (0.10.2)
+    codecov (0.1.17)
+      json
+      simplecov
+      url
     coderay (1.1.3)
     concurrent-ruby (1.1.6)
     crass (1.0.6)
@@ -367,6 +371,7 @@ GEM
     unicorn-worker-killer (0.4.4)
       get_process_mem (~> 0)
       unicorn (>= 4, < 6)
+    url (0.3.2)
     webpacker (5.1.1)
       activesupport (>= 5.2)
       rack-proxy (>= 0.6.1)
@@ -399,6 +404,7 @@ DEPENDENCIES
   capistrano-rbenv
   capistrano3-unicorn
   capybara
+  codecov
   daemons
   delayed_job
   delayed_job_active_record

README.md

@@ -1,4 +1,4 @@
-[![Test Coverage](https://api.codeclimate.com/v1/badges/a51f46fb460a35104d82/test_coverage)](https://codeclimate.com/github/danbooru/danbooru/test_coverage) [![Discord](https://img.shields.io/discord/310432830138089472?label=Discord)](https://discord.gg/eSVKkUF)
+[![codecov](https://codecov.io/gh/danbooru/danbooru/branch/master/graph/badge.svg)](https://codecov.io/gh/danbooru/danbooru) [![Discord](https://img.shields.io/discord/310432830138089472?label=Discord)](https://discord.gg/eSVKkUF)
 
 ## Installation