Attempting to determine FileUtils.rm_rf behavior when symlinks are involved

rm-with-symlinks-test.rb

require 'fileutils'
@basedir = "/tmp/symlink_test"

def print_dir
  Dir.glob('./**/*').each do |path|
    if File.symlink?(path)
      puts "#{path} -> #{File.readlink(path)}"
    else
      puts path
    end
  end
  nil
end

def recreate_base_structure
  FileUtils.mkdir_p @basedir
  FileUtils.cd @basedir
  FileUtils.mkdir_p("foo/fizz")
  FileUtils.touch("foo/a.txt")
  FileUtils.touch("foo/fizz/a.txt")
end

# Case 1: create a dir with a symlink to a file
recreate_base_structure
FileUtils.mkdir_p("bar")
FileUtils.ln_sf(File.join(@basedir, "foo/a.txt"), "bar/b.txt")
print_dir
# ./bar
# ./bar/b.txt -> /tmp/symlink_test/foo/a.txt
# ./foo
# ./foo/a.txt
# ./foo/fizz
# ./foo/fizz/a.txt

# rm_rf the dir with the symlink
FileUtils.rm_rf("bar")
print_dir
# ./foo
# ./foo/a.txt
# ./foo/fizz
# ./foo/fizz/a.txt

# Result 1: dst files remain

# Cast 2: create a dir with a symlink to a dir
recreate_base_structure
FileUtils.mkdir_p("bar")
FileUtils.ln_sf(File.join(@basedir, "foo"), "bar/baz")
print_dir
# ./bar
# ./bar/baz -> /tmp/symlink_test/foo
# ./foo
# ./foo/a.txt
# ./foo/fizz
# ./foo/fizz/a.txt

# rm_rf the dir with the symlink
FileUtils.rm_rf("bar")
print_dir
# ./foo
# ./foo/a.txt
# ./foo/fizz
# ./foo/fizz/a.txt

# Result 2: dst files remain

# Case 3: create a symlink to a dir
recreate_base_structure
FileUtils.ln_sf(File.join(@basedir, "foo"), "baz") unless File.symlink?("baz")
print_dir
# ./baz -> /tmp/symlink_test/foo
# ./foo
# ./foo/a.txt
# ./foo/fizz
# ./foo/fizz/a.txt

# rm_rf the symlink
FileUtils.rm_rf("baz")
print_dir
# ./baz -> /tmp/symlink_test/foo
# ./foo

# Result 3: dst files remain

# Case 4: create a symlink to a dir
recreate_base_structure
FileUtils.ln_sf(File.join(@basedir, "foo"), "baz") unless File.symlink?("baz")
print_dir
# ./baz -> /tmp/symlink_test/foo
# ./foo
# ./foo/a.txt
# ./foo/fizz
# ./foo/fizz/a.txt

# rm_rf the symlink with a trailing slash
FileUtils.rm_rf("baz/")
print_dir
# ./baz -> /tmp/symlink_test/foo
# ./foo

# Result 4: !!! WARNING dst file deleted !!!

# Case 5: create a symlink to a dir
recreate_base_structure
FileUtils.ln_sf(File.join(@basedir, "foo"), "baz") unless File.symlink?("baz")
print_dir
# ./baz -> /tmp/symlink_test/foo
# ./foo
# ./foo/a.txt
# ./foo/fizz
# ./foo/fizz/a.txt

# rm_rf the symlink with a trailing slash+star
FileUtils.rm_rf("baz/*")
print_dir
# ./baz -> /tmp/symlink_test/foo
# ./foo
# ./foo/a.txt
# ./foo/fizz
# ./foo/fizz/a.txt

# Result 5: dst files remain

# Case 6: create a symlink to a dir
recreate_base_structure
FileUtils.ln_sf(File.join(@basedir, "foo"), "baz") unless File.symlink?("baz")
print_dir
# ./baz -> /tmp/symlink_test/foo
# ./foo
# ./foo/a.txt
# ./foo/fizz
# ./foo/fizz/a.txt

# rm_rf the symlink with a dir-recursive star
FileUtils.rm_rf("baz/**/*")
print_dir
# ./baz -> /tmp/symlink_test/foo
# ./foo
# ./foo/a.txt
# ./foo/fizz
# ./foo/fizz/a.txt

# Result 6: dst files remain