introduce `ActiveSupport::Testing::FileFixtures`.

It's a thin layer to provide easy access to sample files throughout
test-cases. This adds the directory `test/fixtures/files` to newly
generated applications.

2 files changed, 29 insertions, 0 deletions

diff --git a/activesupport/test/file_fixtures/sample.txt b/activesupport/test/file_fixtures/sample.txt
new file mode 100644
index 0000000000..0fa80e7383
--- /dev/null
+++ b/activesupport/test/file_fixtures/sample.txt
@@ -0,0 +1 @@
+sample file fixture
diff --git a/activesupport/test/testing/file_fixtures_test.rb b/activesupport/test/testing/file_fixtures_test.rb
new file mode 100644
index 0000000000..91b8a9071c
--- /dev/null
+++ b/activesupport/test/testing/file_fixtures_test.rb
@@ -0,0 +1,28 @@
+require 'abstract_unit'
+
+class FileFixturesTest < ActiveSupport::TestCase
+  self.file_fixture_path = File.expand_path("../../file_fixtures", __FILE__)
+
+  test "#file_fixture returns Pathname to file fixture" do
+    path = file_fixture("sample.txt")
+    assert_kind_of Pathname, path
+    assert_match %r{activesupport/test/file_fixtures/sample.txt$}, path.to_s
+  end
+
+  test "raises an exception when the fixture file does not exist" do
+    e = assert_raises(ArgumentError) do
+      file_fixture("nope")
+    end
+    assert_match(/^the directory '[^']+test\/file_fixtures' does not contain a file named 'nope'$/, e.message)
+  end
+end
+
+class FileFixturesPathnameDirectoryTest < ActiveSupport::TestCase
+  self.file_fixture_path = Pathname.new(File.expand_path("../../file_fixtures", __FILE__))
+
+  test "#file_fixture_path returns Pathname to file fixture" do
+    path = file_fixture("sample.txt")
+    assert_kind_of Pathname, path
+    assert_match %r{activesupport/test/file_fixtures/sample.txt$}, path.to_s
+  end
+end