require "abstract_unit" require "active_support/core_ext/file" class AtomicWriteTest < ActiveSupport::TestCase def test_atomic_write_without_errors contents = "Atomic Text" File.atomic_write(file_name, Dir.pwd) do |file| file.write(contents) assert !File.exist?(file_name) end assert File.exist?(file_name) assert_equal contents, File.read(file_name) ensure File.unlink(file_name) rescue nil end def test_atomic_write_doesnt_write_when_block_raises File.atomic_write(file_name) do |file| file.write("testing") raise "something bad" end rescue assert !File.exist?(file_name) end def test_atomic_write_preserves_file_permissions contents = "Atomic Text" File.open(file_name, "w", 0755) do |file| file.write(contents) assert File.exist?(file_name) end assert File.exist?(file_name) assert_equal 0100755 & ~File.umask, file_mode assert_equal contents, File.read(file_name) File.atomic_write(file_name, Dir.pwd) do |file| file.write(contents) assert File.exist?(file_name) end assert File.exist?(file_name) assert_equal 0100755 & ~File.umask, file_mode assert_equal contents, File.read(file_name) ensure File.unlink(file_name) rescue nil end def test_atomic_write_preserves_default_file_permissions contents = "Atomic Text" File.atomic_write(file_name, Dir.pwd) do |file| file.write(contents) assert !File.exist?(file_name) end assert File.exist?(file_name) assert_equal File.probe_stat_in(Dir.pwd).mode, file_mode assert_equal contents, File.read(file_name) ensure File.unlink(file_name) rescue nil end def test_atomic_write_returns_result_from_yielded_block block_return_value = File.atomic_write(file_name, Dir.pwd) do |file| "Hello world!" end assert_equal "Hello world!", block_return_value ensure File.unlink(file_name) rescue nil end private def file_name "atomic.file" end def file_mode File.stat(file_name).mode end end