Update migration script to test run warnings

When running the entire test suite, many warnings would be output:

/Users/bw/Projects/gollum/test/test_migrate.rb:37: warning: already initialized constant HYPHENATE
/Users/bw/Projects/gollum/test/test_migrate.rb:37: warning: previous definition of HYPHENATE was here
/Users/bw/Projects/gollum/test/test_migrate.rb:37: warning: already initialized constant PAGE_FILE_DIR
/Users/bw/Projects/gollum/test/test_migrate.rb:37: warning: previous definition of PAGE_FILE_DIR was here
/Users/bw/Projects/gollum/bin/gollum-migrate-tags:91: warning: already initialized constant REPO
/Users/bw/Projects/gollum/bin/gollum-migrate-tags:91: warning: previous definition of REPO was here
/Users/bw/Projects/gollum/bin/gollum-migrate-tags:236: warning: already initialized constant TREE
/Users/bw/Projects/gollum/bin/gollum-migrate-tags:236: warning: previous definition of TREE was here
/Users/bw/Projects/gollum/test/test_migrate.rb:37: warning: already initialized constant PAGE_FILE_DIR
/Users/bw/Projects/gollum/test/test_migrate.rb:37: warning: previous definition of PAGE_FILE_DIR was here
/Users/bw/Projects/gollum/bin/gollum-migrate-tags:91: warning: already initialized constant REPO
/Users/bw/Projects/gollum/bin/gollum-migrate-tags:91: warning: previous definition of REPO was here
/Users/bw/Projects/gollum/bin/gollum-migrate-tags:236: warning: already initialized constant TREE
/Users/bw/Projects/gollum/bin/gollum-migrate-tags:236: warning: previous definition of TREE was here

While it's unlikely that end users would ever see these warnings, as
they'd only be running the migration script once, they will always be
shown in our local test runs and CI run output.

So instead of using constants in our migration script, I change the
script to use class variables instead. This should not effect the
functionality of the migration script whatsoever.

bin/gollum-migrate-tags

@@ -11,8 +11,11 @@ migrate_options = {
   :hyphenate => true
 }
 
-def setting(const)
+def setting(variable_name)
-  Object.const_defined?(const.upcase) && Object.const_get(const.upcase)
+  class_variable_name = :"@@#{variable_name.to_s}"
+
+  Object.class_variable_defined?(class_variable_name) &&
+    Object.class_variable_get(class_variable_name)
 end
 
 opts = OptionParser.new do |opts|
@@ -25,7 +28,7 @@ It finds and repairs Gollum link tags that no longer work under 5.x for three re
 * 5.x wiki internal links are no longer 'global'.
 
 * NB: you can use the --lenient-tag-lookup option in gollum >= 5.x to enable 4.x-backwards compatible tags.
-  
+
 See https://github.com/gollum/gollum/wiki/5.0-release-notes#filename-handling for more information.
 Usage of this script comes without any warranty.
 
@@ -38,7 +41,7 @@ You can use the --page-file-dir and --config options as you would normally with
 Requires a non-bare repository. Recommended usage:
 
 1. Clone your wiki's repository to create a backup.
-2. Run this script on your cloned repo. 
+2. Run this script on your cloned repo.
 3. If all looks sane, run the script with the --write option. This will overwrite files in your working directory, but not commit the changes, so you have time to review them.
 4. Do a 'git diff' to inspect the changes.
 5. Commit the changes if all looks sane, and push/pull them back into your original repo.
@@ -52,23 +55,23 @@ EOF
   opts.on('--page-file-dir [PATH]', 'Specify the subdirectory for all pages. Default: repository root.') do |path|
     wiki_options[:page_file_dir] = path
   end
-    
+
   opts.on('--prefer-relative-links', 'When specified, will try to replace broken links with relative links (\'[[Foo/Bar]]\' instead of \'[[/Subdir/Foo/Bar]]\') where possible.') do
     migrate_options[:prefer_relative] = true
   end
-  
+
   opts.on('--hyphenate', 'Default. Repair links that use spaces instead of hyphens: [[Bilbo Baggins]] -> [[Bilbo-Baggins]]') do
     migrate_options[:hyphenate] = true
   end
-  
+
   opts.on('--no-hyphenate', 'Turn off the --hyphenate option.') do
     migrate_options[:hyphenate] = false
   end
-  
+
   opts.on('--run-silent', 'Don\'t output anything.') do
     migrate_options[:run_silent] = true
   end
-  
+
   opts.on('--write', 'No dry run: actually perform the substitutions.') do
     migrate_options[:no_dry_run] = true
   end
@@ -78,8 +81,11 @@ end
 begin
   opts.parse!
   migrate_options.each do |setting, value|
-    const = setting.to_s.upcase
+    variable_name = :"@@#{setting.to_s}"
-    Object.const_set(const, value) unless Object.const_defined?(const)
+
+    unless Object.class_variable_defined?(variable_name)
+      Object.class_variable_set(variable_name, value)
+    end
   end
   wiki_options[:page_file_dir] = setting(:page_file_dir) ? setting(:page_file_dir) : wiki_options[:page_file_dir] # Allow settings :page_file_dir through PAGE_FILE_DIR constant.
 rescue OptionParser::InvalidOption
@@ -88,7 +94,7 @@ rescue OptionParser::InvalidOption
   exit
 end
 
-REPO = ARGV[0] || Dir.pwd
+wiki_directory = ARGV[0] || Dir.pwd
 
 require 'gollum-lib'
 
@@ -98,7 +104,7 @@ if cfg = options[:config]
   cfg = File.join(Dir.getwd, cfg) unless cfg.slice(0) == File::SEPARATOR
   require cfg
 end
-  
+
 class Gollum::Filter::CodeMigrator < Gollum::Filter::Code
   def extract(data)
     case @markup.format
@@ -126,7 +132,7 @@ class Gollum::Filter::CodeMigrator < Gollum::Filter::Code
         next '' if m_end.length < m_start.length
         lang = m_lang ? m_lang.strip.split.first : nil
         cache_codeblock($~.to_s)
-      end  
+      end
     end
 
     data.gsub!(/^([ ]{0,3})``` ?([^\r\n]+)?\r?\n(.+?)\r?\n[ ]{0,3}```[ \t]*\r?$/m) do
@@ -134,7 +140,7 @@ class Gollum::Filter::CodeMigrator < Gollum::Filter::Code
     end
     data
   end
-  
+
   def process(data)
     return data if data.nil? || data.size.zero? || @map.size.zero?
     @map.each do |id, block| ## Just put the code blocks back in verbatim
@@ -142,23 +148,23 @@ class Gollum::Filter::CodeMigrator < Gollum::Filter::Code
     end
     data
   end
-  
+
   def cache_codeblock(block)
     id = "#{open_pattern}#{Digest::SHA1.hexdigest(block)}#{close_pattern}"
     @map[id] = block
     id
   end
 end
-  
+
 class ::Gollum::Filter::TagMigrator < Gollum::Filter::Tags
   def process_tag(tag)
     link_part, extra = parse_tag_parts(tag)
     orig_tag = %{[[#{tag}]]}
     return orig_tag if link_part.nil?
-    
+
     img_args = extra ? [extra, link_part] : [link_part]
     mime = MIME::Types.type_for(::File.extname(img_args.first.to_s)).first
-    
+
     # For any kind of tag other than an internal link: just return the tag.
     if tag =~ /^_TOC_/ || link_part =~ /^_$/ || link_part =~ /^#{INCLUDE_TAG}/ || (mime && mime.content_type =~ /^image/) || process_external_link_tag(link_part, extra) || process_file_link_tag(link_part, extra)
       return orig_tag
@@ -168,7 +174,7 @@ class ::Gollum::Filter::TagMigrator < Gollum::Filter::Tags
     link = link_part
     page = find_page_or_file_from_path(link)
     anchor = nil
-    
+
     if page.nil? # No match yet, now try finding the page with anchor removed
       if pos = link.rindex('#')
         anchor = link[pos..-1]
@@ -203,12 +209,12 @@ class ::Gollum::Filter::TagMigrator < Gollum::Filter::Tags
         pick = possibles.first
         return tag_for_pick(pick, orig_tag, extra, anchor, @markup.page.path)
       end
-        
+
     end
   end
-  
+
   private
-  
+
   def tag_for_pick(pick, orig_tag, extra, anchor, linking_page_path)
     pick = if setting(:prefer_relative)
       overlapping_path = Pathname.new(linking_page_path).dirname.to_s
@@ -220,7 +226,7 @@ class ::Gollum::Filter::TagMigrator < Gollum::Filter::Tags
     end
     new_tag = extra.nil? ? %{[[#{pick}#{anchor}]]} : %{[[#{extra}|#{pick}#{anchor}]]}
     log(:info, "#{@markup.page.path}: Changing #{orig_tag} -> #{new_tag}")
-    new_tag    
+    new_tag
   end
 end
 
@@ -232,8 +238,12 @@ end
 
 filter_chain = [:PlainTextMigrator, :CodeMigrator, :TagMigrator]
 
-wiki = ::Gollum::Wiki.new(REPO, wiki_options.merge({:filter_chain => filter_chain}))
+wiki = ::Gollum::Wiki.new(wiki_directory, wiki_options.merge({:filter_chain => filter_chain}))
-TREE = wiki.tree_list(wiki.ref, true, true).map {|file| ::File.join('/', file.path)}
+
+Object.class_variable_set(
+  :"@@wiki_tree",
+  wiki.tree_list(wiki.ref, true, true).map {|file| ::File.join('/', file.path)}
+)
 
 def find_linked(link)
   link.gsub!(' ', '-') if setting(:hyphenate) # Match paths containing dashes instead of spaces
@@ -243,7 +253,9 @@ def find_linked(link)
   test_path = ::File.extname(link).empty? ? /#{link}\..+/ : link
   # Select pages from the wiki whose path =~ 'Foo/Bar/Samwi.*'
   # Match case-insenstively to mimic 4.x behavior!
-  TREE.select {|path| path =~ /^\/(.*\/)?#{test_path}/i}
+  Object.class_variable_get(:"@@wiki_tree").select { |path|
+    path =~ /^\/(.*\/)?#{test_path}/i
+  }
 end
 
 def log(kind, msg = nil)
@@ -268,4 +280,4 @@ wiki.pages.each do |page|
     f.close
   end
   log(:none, '====')
-end
+end

test/test_migrate.rb

@@ -1,28 +1,6 @@
 # ~*~ encoding: utf-8 ~*~
 require File.expand_path(File.join(File.dirname(__FILE__), 'helper'))
 
-# Original contents of Subdir/Foo.md:
-# waa
-# [[Samwi]]
-# [[samwise gamgee.mediaWiki]]
-# [[Samwise Gamgee.mediawiki]]
-# [[Samwise Gamgee]]
-# [[Test|Samwise Gamgee#Anchor]]
-# [[Waaa|Test]]
-# [[Zaa]]
-
-# Contents of Subdir/Foo.md after successful tag migration
-result = <<EOF
-waa
-[[Samwi]]
-[[/Samwise Gamgee.mediawiki]]
-[[/Samwise Gamgee.mediawiki]]
-[[/Samwise Gamgee.md]]
-[[Test|/Samwise Gamgee.md#Anchor]]
-[[Waaa|/Bar/Test.md]]
-[[Subsub/Zaa.md]]
-EOF
-
 def load_script(**args)
   settings = {
     :run_silent => true,
@@ -31,47 +9,70 @@ def load_script(**args)
     :hyphenate => false,
     :page_file_dir => nil,
   }.merge(args)
-  
+
-  settings.each do |const, val|
+  settings.each do |setting, val|
-    const_name = const.to_s.upcase
+    variable_name = :"@@#{setting.to_s}"
-    Object.const_set(const_name, val) unless Object.const_defined?(const_name) && Object.const_get(const_name) == val
+
+    unless Object.class_variable_defined?(variable_name) && Object.class_variable_get(variable_name) == val
+      Object.class_variable_set(variable_name, val)
+    end
   end
-  
+
   script_path = File.expand_path(File.join(File.dirname(__FILE__), '../', 'bin', 'gollum-migrate-tags'))
-  
+
   Dir.chdir(@path) do
     load script_path
-  end  
+  end
 end
 
 unless ENV['CI']
-
   context '4.x -> 5.x tag migrator' do
     include Rack::Test::Methods
 
     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
-    
+
-      f = ::File.new(::File.join(@path, 'Subdir/Foo.md'), 'r')
+      file = ::File.new(::File.join(@path, 'Subdir/Foo.md'), 'r')
-      assert_equal result, f.read
+      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    
+    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
-    
+
-    test 'migration with page file dir' do      
+    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]]')
@@ -82,5 +83,4 @@ unless ENV['CI']
       FileUtils.rm_rf(@path)
     end
   end
-
+end
-end