Include rdoc as a dependency

We've had some reports (#1342, #1809) of `rdoc` not being installed
in some environments, causing Gollum to error in unpleasant ways.

This isn't an issue that's unique to Gollum, and I don't think `rdoc`
should actually be a hard dependency of this project.  But since we can
side-step the issue by requiring `rdoc`, something that most users who
install Gollum via RubyGems would already have installed, I don't think
this is a horrible solution.

.github/workflows/docker-deploy.yml

@@ -45,5 +45,6 @@ jobs:
           tags: ${{ env.DEPLOY_NAME }}
           cache-from: type=local,src=/tmp/.buildx-cache
           cache-to: type=local,dest=/tmp/.buildx-cache
+          platforms: linux/amd64, linux/arm64
       - name: Image digest
         run: echo ${{ steps.docker_build.outputs.digest }}

Dockerfile

@@ -32,7 +32,8 @@ COPY --from=builder /usr/local/bundle/ /usr/local/bundle/
 
 RUN apk add \
     bash \
-    git
+    git \
+    libc6-compat
 
 VOLUME /wiki
 WORKDIR /wiki

gollum.gemspec

@@ -20,6 +20,7 @@ Gem::Specification.new do |s|
   s.rdoc_options = ['--charset=UTF-8']
   s.extra_rdoc_files = %w[README.md LICENSE]
 
+  s.add_dependency 'rdoc', '~> 6'
   s.add_dependency 'gollum-lib', '~> 5.1'
   s.add_dependency 'kramdown', '~> 2.3'
   s.add_dependency 'kramdown-parser-gfm', '~> 1.1.0'

test/test_migrate.rb

@@ -25,62 +25,60 @@ def load_script(**args)
   end
 end
 
-unless ENV['CI']
-  context '4.x -> 5.x tag migrator' do
-    include Rack::Test::Methods
+context '4.x -> 5.x tag migrator' do
+  include Rack::Test::Methods
 
-    setup do
-      @path = cloned_testpath("examples/lotr_migration.git")
-    end
+  setup do
+    @path = cloned_testpath("examples/lotr_migration.git")
+  end
 
-    test 'repair broken links' do
-      # The original contents of Subdir/Foo.md:
-      #
-      # waa
-      # [[Samwi]]
-      # [[samwise gamgee.mediaWiki]]
-      # [[Samwise Gamgee.mediawiki]]
-      # [[Samwise Gamgee]]
-      # [[Test|Samwise Gamgee#Anchor]]
-      # [[Waaa|Test]]
-      # [[Zaa]]
-      #
-      # The contents will be updated after running the migration script.
-      load_script
+  test 'repair broken links' do
+    # The original contents of Subdir/Foo.md:
+    #
+    # waa
+    # [[Samwi]]
+    # [[samwise gamgee.mediaWiki]]
+    # [[Samwise Gamgee.mediawiki]]
+    # [[Samwise Gamgee]]
+    # [[Test|Samwise Gamgee#Anchor]]
+    # [[Waaa|Test]]
+    # [[Zaa]]
+    #
+    # The contents will be updated after running the migration script.
+    load_script
 
-      file = ::File.new(::File.join(@path, 'Subdir/Foo.md'), 'r')
-      assert_equal <<~FILE_CONTENTS, file.read
-        waa
-        [[Samwi]]
-        [[/Samwise Gamgee.mediawiki]]
-        [[/Samwise Gamgee.mediawiki]]
-        [[/Samwise Gamgee.md]]
-        [[Test|/Samwise Gamgee.md#Anchor]]
-        [[Waaa|/Bar/Test.md]]
-        [[Subsub/Zaa.md]]
-      FILE_CONTENTS
-    end
+    file = ::File.new(::File.join(@path, 'Subdir/Foo.md'), 'r')
+    assert_equal <<~FILE_CONTENTS, file.read
+      waa
+      [[Samwi]]
+      [[/Samwise Gamgee.mediawiki]]
+      [[/Samwise Gamgee.mediawiki]]
+      [[/Samwise Gamgee.md]]
+      [[Test|/Samwise Gamgee.md#Anchor]]
+      [[Waaa|/Bar/Test.md]]
+      [[Subsub/Zaa.md]]
+    FILE_CONTENTS
+  end
 
-    test 'change spaced filenames to hyphenated filenames' do
-      load_script(hyphenate: true)
+  test 'change spaced filenames to hyphenated filenames' do
+    load_script(hyphenate: true)
 
-      f = ::File.new(::File.join(@path, 'Home.textile'), 'r')
-      output = f.read
-      assert_equal true, output.include?('[[Bilbo-Baggins.md]]')
-      assert_equal true, output.include?('[[evil|Mordor/Eye-Of-Sauron.md]]')
-    end
+    f = ::File.new(::File.join(@path, 'Home.textile'), 'r')
+    output = f.read
+    assert_equal true, output.include?('[[Bilbo-Baggins.md]]')
+    assert_equal true, output.include?('[[evil|Mordor/Eye-Of-Sauron.md]]')
+  end
 
-    test 'migration with page file dir' do
-      load_script(page_file_dir: 'Subdir')
+  test 'migration with page file dir' do
+    load_script(page_file_dir: 'Subdir')
 
-      f = ::File.new(::File.join(@path, 'Subdir/Foo.md'), 'r')
-      output = f.read
-      assert_equal true, output.include?('[[Subsub/Zaa.md]]')
-      assert_equal true, output.include?('[[Samwi]]')
-    end
+    f = ::File.new(::File.join(@path, 'Subdir/Foo.md'), 'r')
+    output = f.read
+    assert_equal true, output.include?('[[Subsub/Zaa.md]]')
+    assert_equal true, output.include?('[[Samwi]]')
+  end
 
-    teardown do
-      FileUtils.rm_rf(@path)
-    end
+  teardown do
+    FileUtils.rm_rf(@path)
   end
 end