Add tests against resolver

We didn't previously have many tests directly against the
OptimizedFileSystemResolver or FileSystemResolver, though usually
failures would be exposed through other tests.

It's easier to test some specifics of the behaviour with unit tests.
This also lets us test FileSystemResolver (non-optimized) which I don't
think previously had much testing (other than from classses inheriting
it).

3 files changed, 109 insertions, 0 deletions

diff --git a/actionview/test/template/file_system_resolver_test.rb b/actionview/test/template/file_system_resolver_test.rb
new file mode 100644
index 0000000000..aa03fdcb13
--- /dev/null
+++ b/actionview/test/template/file_system_resolver_test.rb
@@ -0,0 +1,12 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "template/resolver_shared_tests"
+
+class FileSystemResolverTest < ActiveSupport::TestCase
+  include ResolverSharedTests
+
+  def resolver
+    ActionView::FileSystemResolver.new(tmpdir)
+  end
+end
diff --git a/actionview/test/template/optimized_file_system_resolver_test.rb b/actionview/test/template/optimized_file_system_resolver_test.rb
new file mode 100644
index 0000000000..c0c64357ce
--- /dev/null
+++ b/actionview/test/template/optimized_file_system_resolver_test.rb
@@ -0,0 +1,12 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+require "template/resolver_shared_tests"
+
+class OptimizedFileSystemResolverTest < ActiveSupport::TestCase
+  include ResolverSharedTests
+
+  def resolver
+    ActionView::OptimizedFileSystemResolver.new(tmpdir)
+  end
+end
diff --git a/actionview/test/template/resolver_shared_tests.rb b/actionview/test/template/resolver_shared_tests.rb
new file mode 100644
index 0000000000..dee6a69c66
--- /dev/null
+++ b/actionview/test/template/resolver_shared_tests.rb
@@ -0,0 +1,85 @@
+module ResolverSharedTests
+  attr_reader :tmpdir
+
+  def run(*args)
+    capture_exceptions do
+      Dir.mktmpdir(nil, __dir__) { |dir| @tmpdir = dir; super }
+    end
+  end
+
+  def with_file(filename, source="File at #{filename}")
+    path = File.join(tmpdir, filename)
+    FileUtils.mkdir_p(File.dirname(path))
+    File.write(path, source)
+  end
+
+  def test_can_find_with_no_extensions
+    with_file "test/hello_world", "Hello default!"
+
+    templates = resolver.find_all("hello_world", "test", false, locale: [:en], formats: [:html], variants: [:phone], handlers: [:erb])
+    assert_equal 1, templates.size
+    assert_equal "Hello default!",   templates[0].source
+    assert_equal "test/hello_world", templates[0].virtual_path
+    assert_nil templates[0].format
+    assert_nil templates[0].variant
+    assert_kind_of ActionView::Template::Handlers::Raw, templates[0].handler
+  end
+
+  def test_can_find_with_just_handler
+    with_file "test/hello_world.erb", "Hello erb!"
+
+    templates = resolver.find_all("hello_world", "test", false, locale: [:en], formats: [:html], variants: [:phone], handlers: [:erb])
+    assert_equal 1, templates.size
+    assert_equal "Hello erb!",   templates[0].source
+    assert_equal "test/hello_world", templates[0].virtual_path
+    assert_nil templates[0].format
+    assert_nil templates[0].variant
+    assert_kind_of ActionView::Template::Handlers::ERB, templates[0].handler
+  end
+
+  def test_can_find_with_format_and_handler
+    with_file "test/hello_world.text.builder", "Hello plain text!"
+
+    templates = resolver.find_all("hello_world", "test", false, locale: [:en], formats: [:html, :text], variants: [:phone], handlers: [:erb, :builder])
+    assert_equal 1, templates.size
+    assert_equal "Hello plain text!", templates[0].source
+    assert_equal "test/hello_world",  templates[0].virtual_path
+    assert_equal :text, templates[0].format
+    assert_nil templates[0].variant
+    assert_kind_of ActionView::Template::Handlers::Builder, templates[0].handler
+  end
+
+  def test_can_find_with_variant_format_and_handler
+    with_file "test/hello_world.html+phone.erb", "Hello plain text!"
+
+    templates = resolver.find_all("hello_world", "test", false, locale: [:en], formats: [:html], variants: [:phone], handlers: [:erb])
+    assert_equal 1, templates.size
+    assert_equal "Hello plain text!", templates[0].source
+    assert_equal "test/hello_world",  templates[0].virtual_path
+    assert_equal :html, templates[0].format
+    assert_equal "phone", templates[0].variant
+    assert_kind_of ActionView::Template::Handlers::ERB, templates[0].handler
+  end
+
+  def test_can_find_with_any_variant_format_and_handler
+    with_file "test/hello_world.html+phone.erb", "Hello plain text!"
+
+    templates = resolver.find_all("hello_world", "test", false, locale: [:en], formats: [:html], variants: :any, handlers: [:erb])
+    assert_equal 1, templates.size
+    assert_equal "Hello plain text!", templates[0].source
+    assert_equal "test/hello_world",  templates[0].virtual_path
+    assert_equal :html, templates[0].format
+    assert_equal "phone", templates[0].variant
+    assert_kind_of ActionView::Template::Handlers::ERB, templates[0].handler
+  end
+
+  def test_doesnt_find_template_with_wrong_details
+    with_file "test/hello_world.html.erb", "Hello plain text!"
+
+    templates = resolver.find_all("hello_world", "test", false, locale: [], formats: [:xml], variants: :any, handlers: [:builder])
+    assert_equal 0, templates.size
+
+    templates = resolver.find_all("hello_world", "test", false, locale: [], formats: [:xml], variants: :any, handlers: [:erb])
+    assert_equal 0, templates.size
+  end
+end