1 files changed, 97 insertions, 0 deletions
diff --git a/lib/rdoc/ri/paths.rb b/lib/rdoc/ri/paths.rb
new file mode 100644
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+++ b/lib/rdoc/ri/paths.rb
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+require 'rdoc/ri'
+
+##
+# Encapsulate all the strangeness to do with finding out where to find RDoc
+# files
+#
+# We basically deal with three directories:
+#
+# 1. The 'system' documentation directory, which holds the documentation
+#    distributed with Ruby, and which is managed by the Ruby install process
+# 2. The 'site' directory, which contains site-wide documentation added
+#    locally.
+# 3. The 'user' documentation directory, stored under the user's own home
+#    directory.
+#
+# There's contention about all this, but for now:
+#
+# system:: $datadir/ri/<ver>/system/...
+# site::   $datadir/ri/<ver>/site/...
+# user::   ~/.rdoc
+
+module RDoc::RI::Paths
+
+  #:stopdoc:
+  require 'rbconfig'
+
+  DOC_DIR  = "doc/rdoc"
+
+  version = RbConfig::CONFIG['ruby_version']
+
+  base    = File.join(RbConfig::CONFIG['datadir'], "ri", version)
+  SYSDIR  = File.join(base, "system")
+  SITEDIR = File.join(base, "site")
+  homedir = ENV['HOME'] || ENV['USERPROFILE'] || ENV['HOMEPATH']
+
+  if homedir then
+    HOMEDIR = File.join(homedir, ".rdoc")
+  else
+    HOMEDIR = nil
+  end
+
+  # This is the search path for 'ri'
+  PATH = [ SYSDIR, SITEDIR, HOMEDIR ].find_all {|p| p && File.directory?(p)}
+
+  require 'rubygems' unless defined?(Gem) and Gem::Enable
+
+  # HACK dup'd from Gem.latest_partials and friends
+  all_paths = []
+
+  all_paths = Gem.path.map do |dir|
+    Dir[File.join(dir, 'doc', '*', 'ri')]
+  end.flatten
+
+  ri_paths = {}
+
+  all_paths.each do |dir|
+    base = File.basename File.dirname(dir)
+    if base =~ /(.*)-((\d+\.)*\d+)/ then
+      name, version = $1, $2
+      ver = Gem::Version.new version
+      if ri_paths[name].nil? or ver > ri_paths[name][0] then
+        ri_paths[name] = [ver, dir]
+      end
+    end
+  end
+
+  GEMDIRS = ri_paths.map { |k,v| v.last }.sort
+  GEMDIRS.each { |dir| PATH << dir }
+
+  # Returns the selected documentation directories as an Array, or PATH if no
+  # overriding directories were given.
+
+  def self.path(use_system, use_site, use_home, use_gems, *extra_dirs)
+    path = raw_path(use_system, use_site, use_home, use_gems, *extra_dirs)
+    return path.select { |directory| File.directory? directory }
+  end
+
+  # Returns the selected documentation directories including nonexistent
+  # directories.  Used to print out what paths were searched if no ri was
+  # found.
+
+  def self.raw_path(use_system, use_site, use_home, use_gems, *extra_dirs)
+    return PATH unless use_system or use_site or use_home or use_gems or
+                       not extra_dirs.empty?
+
+    path = []
+    path << extra_dirs unless extra_dirs.empty?
+    path << SYSDIR if use_system
+    path << SITEDIR if use_site
+    path << HOMEDIR if use_home
+    path << GEMDIRS if use_gems
+
+    return path.flatten.compact
+  end
+
+end
+