object_file_spec.rb in assembly-objectfile-2.0.0

- old
+ new
@@ -1,222 +1,461 @@
 # frozen_string_literal: true
 
 require 'spec_helper'
 
 describe Assembly::ObjectFile do
-  it 'does not run if no input file is passed in' do
-    object_file = described_class.new('')
-    expect { object_file.filesize }.to raise_error(RuntimeError, 'input file  does not exist or is a directory')
-    expect { object_file.sha1 }.to raise_error(RuntimeError, 'input file  does not exist or is a directory')
-    expect { object_file.md5 }.to raise_error(RuntimeError, 'input file  does not exist or is a directory')
-  end
+  describe '.common_path' do
+    context 'when common path is 2 nodes out of 4' do
+      it 'returns the common directory' do
+        expect(described_class.common_path(['/Users/peter/00/test.tif', '/Users/peter/05/test.jp2'])).to eq('/Users/peter/')
+      end
+    end
 
-  it 'returns the common directory of a set of filenames passed into it, where the common part does not terminate on a directory' do
-    expect(described_class.common_path(['/Users/peter/00/test.tif', '/Users/peter/05/test.jp2'])).to eq('/Users/peter/')
-  end
+    context 'when common path is 3 nodes out of 4' do
+      it 'returns the common directory' do
+        expect(described_class.common_path(['/Users/peter/00/test.tif', '/Users/peter/00/test.jp2'])).to eq('/Users/peter/00/')
+      end
+    end
 
-  it 'returns the common directory of a set of filenames passed into it, where the common part does not terminate on a directory' do
-    expect(described_class.common_path(['/Users/peter/00/test.tif', '/Users/peter/00/test.jp2'])).to eq('/Users/peter/00/')
+    context 'when all in list terminate in diff directories' do
+      it 'returns the common directory' do
+        expect(described_class.common_path(['/Users/peter/00', '/Users/peter/05'])).to eq('/Users/peter/')
+      end
+    end
   end
 
-  it 'tells us if an input file is an image' do
-    expect(File.exist?(TEST_TIF_INPUT_FILE)).to be true
-    object_file = described_class.new(TEST_TIF_INPUT_FILE)
-    expect(object_file.image?).to be(true)
-    expect(object_file.exif).not_to be_nil
-    expect(object_file.mimetype).to eq('image/tiff')
-    expect(object_file.file_mimetype).to eq('image/tiff')
-    expect(object_file.extension_mimetype).to eq('image/tiff')
-    expect(object_file.exif_mimetype).to eq('image/tiff')
-    expect(object_file.object_type).to eq(:image)
-    expect(object_file.valid_image?).to be(true)
-    expect(object_file.jp2able?).to be(true)
-  end
+  describe '#new' do
+    context 'without params' do
+      it 'does not set attributes' do
+        object_file = described_class.new('/some/file.txt')
+        expect(object_file.path).to eq('/some/file.txt')
+        expect(object_file.label).to be_nil
+        expect(object_file.file_attributes).to be_nil
+        expect(object_file.provider_sha1).to be_nil
+        expect(object_file.provider_md5).to be_nil
+        expect(object_file.relative_path).to be_nil
+      end
+    end
 
-  it 'tells us information about the input file' do
-    object_file = described_class.new(TEST_TIF_INPUT_FILE)
-    expect(object_file.filename).to eq('test.tif')
-    expect(object_file.ext).to eq('.tif')
-    expect(object_file.filename_without_ext).to eq('test')
-    expect(object_file.dirname).to eq(File.dirname(TEST_TIF_INPUT_FILE))
-  end
+    context 'with params' do
+      it 'sets attributes to passed params' do
+        object_file = described_class.new('/some/file.txt', label: 'some label', file_attributes: { 'shelve' => 'yes', 'publish' => 'yes', 'preserve' => 'no' }, relative_path: '/tmp')
+        expect(object_file.path).to eq('/some/file.txt')
+        expect(object_file.label).to eq('some label')
+        expect(object_file.file_attributes).to eq('shelve' => 'yes', 'publish' => 'yes', 'preserve' => 'no')
+        expect(object_file.provider_sha1).to be_nil
+        expect(object_file.provider_md5).to be_nil
+        expect(object_file.relative_path).to eq('/tmp')
+      end
 
-  it 'sets the correct mimetype of plain/text for .txt files' do
-    object_file = described_class.new(TEST_RES1_TEXT)
-    expect(object_file.mimetype).to eq('text/plain')
+      it 'sets provider_md5 to passed param' do
+        object_file = described_class.new('/some/file.txt', provider_md5: 'XYZ')
+        expect(object_file.provider_md5).to eq('XYZ')
+      end
+    end
   end
 
-  it 'sets the correct mimetype of plain/text for .xml files' do
-    object_file = described_class.new(TEST_RES1_TEXT)
-    expect(object_file.mimetype).to eq('text/plain')
+  describe '#filename' do
+    it 'returns File.basename' do
+      object_file = described_class.new(TEST_TIF_INPUT_FILE)
+      expect(object_file.filename).to eq('test.tif')
+      expect(object_file.filename).to eq(File.basename(TEST_TIF_INPUT_FILE))
+    end
   end
 
-  it 'sets the correct mimetype of plain/text for .obj 3d files' do
-    object_file = described_class.new(TEST_OBJ_FILE)
-    expect(object_file.mimetype).to eq('text/plain')
+  describe '#ext' do
+    it 'returns the file extension' do
+      object_file = described_class.new(TEST_TIF_INPUT_FILE)
+      expect(object_file.ext).to eq('.tif')
+    end
   end
 
-  it 'sets a mimetype of application/x-tgif for .obj 3d files if we prefer the mimetype extension gem over unix file system command' do
-    object_file = described_class.new(TEST_OBJ_FILE, mime_type_order: %i[extension file exif])
-    expect(object_file.mimetype).to eq('application/x-tgif')
+  describe '#dirname' do
+    it 'returns the File.dirname' do
+      object_file = described_class.new(TEST_TIF_INPUT_FILE)
+      expect(object_file.dirname).to eq(File.dirname(TEST_TIF_INPUT_FILE))
+    end
   end
 
-  it 'ignores invald mimetype generation methods and still sets a mimetype of application/x-tgif for .obj 3d files if we prefer the mimetype extension gem over unix file system command' do
-    object_file = described_class.new(TEST_OBJ_FILE, mime_type_order: %i[bogus extension file])
-    expect(object_file.mimetype).to eq('application/x-tgif')
+  describe '#filename_without_ext' do
+    it 'returns filename before extension' do
+      object_file = described_class.new(TEST_TIF_INPUT_FILE)
+      expect(object_file.filename_without_ext).to eq('test')
+    end
   end
 
-  it 'sets the correct mimetype of plain/text for .ply 3d files' do
-    object_file = described_class.new(TEST_PLY_FILE)
-    expect(object_file.mimetype).to eq('text/plain')
-  end
+  describe '#image?' do
+    context 'with tiff' do
+      it 'true' do
+        object_file = described_class.new(TEST_TIF_INPUT_FILE)
+        expect(object_file.image?).to be(true)
+      end
+    end
 
-  it 'overrides the mimetype generators and uses the manual mapping to set the correct mimetype of application/json for a .json file' do
-    object_file = described_class.new(TEST_JSON_FILE)
-    expect(object_file.exif_mimetype).to be_nil # exif returns nil
-    expect(object_file.file_mimetype).to eq('text/plain') # unix file system command returns plain text
-    expect(object_file.mimetype).to eq('application/json') # but our configured mapping overrides both and returns application/json
-  end
+    context 'with jp2' do
+      it 'true' do
+        object_file = described_class.new(TEST_JP2_INPUT_FILE)
+        expect(object_file.image?).to be(true)
+      end
+    end
 
-  it 'sets the correct mimetype of image/tiff for .tif files' do
-    object_file = described_class.new(TEST_TIF_INPUT_FILE)
-    expect(object_file.mimetype).to eq('image/tiff')
-  end
+    context 'with ruby file' do
+      it 'false' do
+        non_image_file = File.join(Assembly::PATH_TO_GEM, 'spec/object_file_spec.rb')
+        object_file = described_class.new(non_image_file)
+        expect(object_file.image?).to be(false)
+      end
+    end
 
-  it 'sets the correct mimetype of image/jp2 for .jp2 files' do
-    object_file = described_class.new(TEST_JP2_INPUT_FILE)
-    expect(object_file.mimetype).to eq('image/jp2')
+    context 'with xml' do
+      it 'false' do
+        non_image_file = File.join(Assembly::PATH_TO_GEM, 'spec/test_data/input/file_with_no_exif.xml')
+        object_file = described_class.new(non_image_file)
+        expect(object_file.image?).to be(false)
+      end
+    end
   end
 
-  it 'sets the correct mimetype of application/pdf for .pdf files' do
-    object_file = described_class.new(TEST_RES1_PDF)
-    expect(object_file.mimetype).to eq('application/pdf')
-  end
+  describe '#object_type' do
+    context 'with tiff' do
+      it ':image' do
+        object_file = described_class.new(TEST_TIF_INPUT_FILE)
+        expect(object_file.object_type).to eq(:image)
+      end
+    end
 
-  it 'gives us the mimetype of a file even if the exif information is damaged' do
-    object_file = described_class.new(TEST_FILE_NO_EXIF)
-    expect(object_file.filename).to eq('file_with_no_exif.xml')
-    expect(object_file.ext).to eq('.xml')
-    expect(['text/html', 'application/xml'].include?(object_file.mimetype)).to be true # we could get either of these mimetypes depending on the OS
+    context 'with jp2' do
+      it ':image' do
+        object_file = described_class.new(TEST_JP2_INPUT_FILE)
+        expect(object_file.object_type).to eq(:image)
+      end
+    end
+
+    context 'with ruby file' do
+      it ':text' do
+        non_image_file = File.join(Assembly::PATH_TO_GEM, 'spec/object_file_spec.rb')
+        object_file = described_class.new(non_image_file)
+        expect(object_file.object_type).to eq(:text)
+      end
+    end
+
+    context 'with xml' do
+      it ':application' do
+        non_image_file = File.join(Assembly::PATH_TO_GEM, 'spec/test_data/input/file_with_no_exif.xml')
+        object_file = described_class.new(non_image_file)
+        expect(object_file.object_type).to eq(:application)
+      end
+    end
   end
 
-  it 'gives us the DPG base name for a file' do
-    test_file = File.join(TEST_INPUT_DIR, 'oo000oo0001_00_001.tif')
-    object_file = described_class.new(test_file)
-    expect(object_file.dpg_basename).to eq('oo000oo0001_001')
+  describe '#valid_image?' do
+    context 'with tiff' do
+      it 'true' do
+        object_file = described_class.new(TEST_TIF_INPUT_FILE)
+        expect(object_file.valid_image?).to be(true)
+      end
+    end
+
+    context 'with tiff resolution 1' do
+      it 'true' do
+        object_file = described_class.new(TEST_RES1_TIF1)
+        expect(object_file.valid_image?).to be(true)
+      end
+    end
+
+    context 'with tiff no color' do
+      it 'true' do
+        object_file = described_class.new(TEST_TIFF_NO_COLOR_FILE)
+        expect(object_file.valid_image?).to be(true)
+      end
+    end
+
+    context 'with jp2' do
+      it 'true' do
+        object_file = described_class.new(TEST_JP2_INPUT_FILE)
+        expect(object_file.valid_image?).to be(true)
+      end
+    end
+
+    context 'with ruby file' do
+      it 'false' do
+        non_image_file = File.join(Assembly::PATH_TO_GEM, 'spec/object_file_spec.rb')
+        object_file = described_class.new(non_image_file)
+        expect(object_file.valid_image?).to be(false)
+      end
+    end
+
+    context 'with xml' do
+      it 'false' do
+        non_image_file = File.join(Assembly::PATH_TO_GEM, 'spec/test_data/input/file_with_no_exif.xml')
+        object_file = described_class.new(non_image_file)
+        expect(object_file.valid_image?).to be(false)
+      end
+    end
   end
 
-  it 'gives us the DPG subfolder name for a file' do
-    test_file = File.join(TEST_INPUT_DIR, 'oo000oo0001_05_001.tif')
-    object_file = described_class.new(test_file)
-    expect(object_file.dpg_folder).to eq('05')
+  describe '#mimetype' do
+    # rubocop:disable RSpec/RepeatedExampleGroupBody
+    context 'with .txt file' do
+      it 'plain/text' do
+        object_file = described_class.new(TEST_RES1_TEXT)
+        expect(object_file.mimetype).to eq('text/plain')
+      end
+    end
+
+    context 'with .xml file' do
+      it 'plain/text' do
+        object_file = described_class.new(TEST_RES1_TEXT)
+        expect(object_file.mimetype).to eq('text/plain')
+      end
+    end
+    # rubocop:enable RSpec/RepeatedExampleGroupBody
+
+    context 'with .tif file' do
+      it 'image/tiff' do
+        object_file = described_class.new(TEST_TIF_INPUT_FILE)
+        expect(object_file.mimetype).to eq('image/tiff')
+      end
+    end
+
+    context 'with .jp2 file' do
+      it 'image/jp2' do
+        object_file = described_class.new(TEST_JP2_INPUT_FILE)
+        expect(object_file.mimetype).to eq('image/jp2')
+      end
+    end
+
+    context 'with .pdf file' do
+      it 'application/pdf' do
+        object_file = described_class.new(TEST_RES1_PDF)
+        expect(object_file.mimetype).to eq('application/pdf')
+      end
+    end
+
+    context 'with .obj (3d) file' do
+      context 'when default preference (unix file system command)' do
+        it 'plain/text' do
+          object_file = described_class.new(TEST_OBJ_FILE)
+          expect(object_file.mimetype).to eq('text/plain')
+        end
+      end
+
+      context 'when mimetype extension gem preferred over unix file system command' do
+        it 'application/x-tgif' do
+          object_file = described_class.new(TEST_OBJ_FILE, mime_type_order: %i[extension file exif])
+          expect(object_file.mimetype).to eq('application/x-tgif')
+        end
+      end
+
+      context 'when invalid first preference mimetype generation' do
+        it 'ignores invalid mimetype generation method and respects valid method preference order' do
+          object_file = described_class.new(TEST_OBJ_FILE, mime_type_order: %i[bogus extension file])
+          expect(object_file.mimetype).to eq('application/x-tgif')
+        end
+      end
+    end
+
+    context 'with .ply 3d file' do
+      it 'text/plain' do
+        object_file = described_class.new(TEST_PLY_FILE)
+        expect(object_file.mimetype).to eq('text/plain')
+      end
+    end
+
+    context 'when exif information is damaged' do
+      it 'gives us the mimetype' do
+        object_file = described_class.new(TEST_FILE_NO_EXIF)
+        expect(object_file.filename).to eq('file_with_no_exif.xml')
+        expect(object_file.ext).to eq('.xml')
+        # we could get either of these mimetypes depending on the OS
+        expect(['text/html', 'application/xml'].include?(object_file.mimetype)).to be true
+      end
+    end
+
+    context 'when .json file' do
+      it 'uses the manual mapping to set the correct mimetype of application/json for a .json file' do
+        object_file = described_class.new(TEST_JSON_FILE)
+        expect(object_file.send(:exif_mimetype)).to be_nil # exif
+        expect(object_file.send(:file_mimetype)).to eq('text/plain') # unix file system command
+        expect(object_file.mimetype).to eq('application/json') # our configured mapping overrides both
+      end
+    end
   end
 
-  it 'tells us that a jp2 file is not jp2able but does have a color profile' do
-    expect(File.exist?(TEST_JP2_INPUT_FILE)).to be true
-    object_file = described_class.new(TEST_JP2_INPUT_FILE)
-    expect(object_file.image?).to be(true)
-    expect(object_file.object_type).to eq(:image)
-    expect(object_file.valid_image?).to be(true)
-    expect(object_file.jp2able?).to be(false)
-    expect(object_file.has_color_profile?).to be(true)
+  describe '#file_mimetype (unix file system command)' do
+    context 'when .json file' do
+      it 'text/plain' do
+        object_file = described_class.new(TEST_JSON_FILE)
+        expect(object_file.send(:file_mimetype)).to eq('text/plain')
+      end
+    end
+
+    context 'when .tif file' do
+      it 'image/tiff' do
+        object_file = described_class.new(TEST_TIF_INPUT_FILE)
+        expect(object_file.send(:file_mimetype)).to eq('image/tiff')
+      end
+    end
   end
 
-  it 'tells us that a tiff file is jp2able and has a color profile' do
-    expect(File.exist?(TEST_RES1_TIF1)).to be true
-    object_file = described_class.new(TEST_RES1_TIF1)
-    expect(object_file.image?).to be(true)
-    expect(object_file.object_type).to eq(:image)
-    expect(object_file.valid_image?).to be(true)
-    expect(object_file.jp2able?).to be(true)
-    expect(object_file.has_color_profile?).to be(true)
+  describe '#jp2able?' do
+    context 'with jp2 file' do
+      it 'false' do
+        object_file = described_class.new(TEST_JP2_INPUT_FILE)
+        expect(object_file.jp2able?).to be(false)
+      end
+    end
+
+    context 'with tiff resolution 1 file' do
+      it 'true' do
+        object_file = described_class.new(TEST_RES1_TIF1)
+        expect(object_file.jp2able?).to be(true)
+      end
+    end
+
+    context 'with tiff no color file' do
+      it 'true' do
+        object_file = described_class.new(TEST_TIFF_NO_COLOR_FILE)
+        expect(object_file.jp2able?).to be(true)
+      end
+    end
   end
 
-  it 'tells us that a tiff file is not jp2able and is not valid since it has no profile' do
-    expect(File.exist?(TEST_TIFF_NO_COLOR_FILE)).to be true
-    object_file = described_class.new(TEST_TIFF_NO_COLOR_FILE)
-    expect(object_file.image?).to be(true)
-    expect(object_file.object_type).to eq(:image)
-    expect(object_file.valid_image?).to be(true)
-    expect(object_file.jp2able?).to be(true)
-    expect(object_file.has_color_profile?).to be(false)
+  describe '#has_color_profile?' do
+    context 'with jp2 file' do
+      it 'true' do
+        object_file = described_class.new(TEST_JP2_INPUT_FILE)
+        expect(object_file.has_color_profile?).to be(true)
+      end
+    end
+
+    context 'with tiff file' do
+      it 'true' do
+        object_file = described_class.new(TEST_RES1_TIF1)
+        expect(object_file.has_color_profile?).to be(true)
+      end
+    end
+
+    context 'with tiff no color file' do
+      it 'false' do
+        object_file = described_class.new(TEST_TIFF_NO_COLOR_FILE)
+        expect(object_file.has_color_profile?).to be(false)
+      end
+    end
   end
 
-  it 'computes checksums for an image file' do
-    expect(File.exist?(TEST_TIF_INPUT_FILE)).to be true
-    object_file = described_class.new(TEST_TIF_INPUT_FILE)
-    expect(object_file.md5).to eq('a2400500acf21e43f5440d93be894101')
-    expect(object_file.sha1).to eq('8d11fab63089a24c8b17063d29a4b0eac359fb41')
+  describe '#md5' do
+    it 'computes md5 for an image file' do
+      object_file = described_class.new(TEST_TIF_INPUT_FILE)
+      expect(object_file.md5).to eq('a2400500acf21e43f5440d93be894101')
+    end
+
+    it 'raises RuntimeError if no input file is passed in' do
+      object_file = described_class.new('')
+      expect { object_file.md5 }.to raise_error(RuntimeError, 'input file  does not exist or is a directory')
+    end
   end
 
-  it 'indicates that the file is not found when a valid directory is supplied instead of a file or when an invalid file path is specified' do
-    path = Assembly::PATH_TO_GEM
-    object_file = described_class.new(path)
-    expect(File.exist?(path)).to be true
-    expect(File.directory?(path)).to be true
-    expect(object_file.file_exists?).to be false
+  describe '#sha1' do
+    it 'computes sha1 for an image file' do
+      object_file = described_class.new(TEST_TIF_INPUT_FILE)
+      expect(object_file.sha1).to eq('8d11fab63089a24c8b17063d29a4b0eac359fb41')
+    end
 
-    path = File.join(Assembly::PATH_TO_GEM, 'bogus.txt')
-    object_file = described_class.new(path)
-    expect(File.exist?(path)).to be false
-    expect(File.directory?(path)).to be false
-    expect(object_file.file_exists?).to be false
+    it 'raises RuntimeError if no input file is passed in' do
+      object_file = described_class.new('')
+      expect { object_file.sha1 }.to raise_error(RuntimeError, 'input file  does not exist or is a directory')
+    end
   end
 
-  it 'sets attributes correctly when initializing' do
-    object_file = described_class.new('/some/file.txt')
-    expect(object_file.path).to eq('/some/file.txt')
-    expect(object_file.label).to be_nil
-    expect(object_file.file_attributes).to be_nil
-    expect(object_file.provider_sha1).to be_nil
-    expect(object_file.provider_md5).to be_nil
-    expect(object_file.relative_path).to be_nil
+  describe '#file_exists?' do
+    it 'false when a valid directory is specified instead of a file' do
+      path = Assembly::PATH_TO_GEM
+      object_file = described_class.new(path)
+      expect(File.exist?(path)).to be true
+      expect(File.directory?(path)).to be true
+      expect(object_file.file_exists?).to be false
+    end
 
-    object_file = described_class.new('/some/file.txt', label: 'some label', file_attributes: { 'shelve' => 'yes', 'publish' => 'yes', 'preserve' => 'no' }, relative_path: '/tmp')
-    expect(object_file.path).to eq('/some/file.txt')
-    expect(object_file.label).to eq('some label')
-    expect(object_file.file_attributes).to eq('shelve' => 'yes', 'publish' => 'yes', 'preserve' => 'no')
-    expect(object_file.provider_sha1).to be_nil
-    expect(object_file.provider_md5).to be_nil
-    expect(object_file.relative_path).to eq('/tmp')
+    it 'false when a non-existent file is specified' do
+      path = File.join(Assembly::PATH_TO_GEM, 'file_not_there.txt')
+      object_file = described_class.new(path)
+      expect(File.exist?(path)).to be false
+      expect(File.directory?(path)).to be false
+      expect(object_file.file_exists?).to be false
+    end
   end
 
-  it 'sets md5_provider attribute' do
-    object_file = described_class.new('/some/file.txt', provider_md5: 'XYZ')
-    expect(object_file.provider_md5).to eq('XYZ')
+  describe '#filesize' do
+    it 'tells us the size of an input file' do
+      object_file = described_class.new(TEST_TIF_INPUT_FILE)
+      expect(object_file.filesize).to eq(63_542)
+    end
+
+    it 'raises RuntimeError if no file is passed in' do
+      object_file = described_class.new('')
+      expect { object_file.filesize }.to raise_error(RuntimeError, 'input file  does not exist or is a directory')
+    end
   end
 
-  it 'tells us if an input file is not an image' do
-    non_image_file = File.join(Assembly::PATH_TO_GEM, 'spec/object_file_spec.rb')
-    expect(File.exist?(non_image_file)).to be true
-    object_file = described_class.new(non_image_file)
-    expect(object_file.image?).to be(false)
-    expect(object_file.object_type).not_to eq(:image)
-    expect(object_file.valid_image?).to be(false)
+  describe '#encoding' do
+    context 'with .tif file' do
+      it 'binary' do
+        object_file = described_class.new(TEST_TIF_INPUT_FILE)
+        expect(object_file.send(:encoding)).to eq('binary')
+      end
+    end
 
-    non_image_file = File.join(Assembly::PATH_TO_GEM, 'spec/test_data/input/file_with_no_exif.xml')
-    expect(File.exist?(non_image_file)).to be true
-    object_file = described_class.new(non_image_file)
-    expect(object_file.image?).to be(false)
-    expect(object_file.object_type).not_to eq(:image)
-    expect(object_file.valid_image?).to be(false)
+    context 'with .txt file' do
+      it 'binary' do
+        object_file = described_class.new(TEST_RES1_TEXT)
+        expect(object_file.send(:encoding)).to eq('us-ascii')
+      end
+    end
   end
 
-  it 'tells us the size of an input file' do
-    expect(File.exist?(TEST_TIF_INPUT_FILE)).to be true
-    object_file = described_class.new(TEST_TIF_INPUT_FILE)
-    expect(object_file.filesize).to eq(63_542)
+  describe '#exif' do
+    it 'returns MiniExiftool object' do
+      object_file = described_class.new(TEST_TIF_INPUT_FILE)
+      expect(object_file.exif).not_to be_nil
+      expect(object_file.exif.class).to eq MiniExiftool
+    end
+
+    it 'raises MiniExiftool::Error if exiftool raises one' do
+      object_file = described_class.new('spec/test_data/empty.txt')
+      expect { object_file.exif }.to raise_error(MiniExiftool::Error)
+    end
   end
 
-  it 'tells us the mimetype and encoding of an input file' do
-    expect(File.exist?(TEST_TIF_INPUT_FILE)).to be true
-    @ai = described_class.new(TEST_TIF_INPUT_FILE)
-    expect(@ai.mimetype).to eq('image/tiff')
-    expect(@ai.file_mimetype).to eq('image/tiff')
-    expect(@ai.encoding).to eq('binary')
+  describe '#extension_mimetype' do
+    # mime-types gem, based on a file extension lookup
+    context 'with .obj file' do
+      it 'application/x-tgif' do
+        object_file = described_class.new(TEST_OBJ_FILE)
+        expect(object_file.send(:extension_mimetype)).to eq('application/x-tgif')
+      end
+    end
+
+    context 'with .tif file' do
+      it 'image/tiff' do
+        object_file = described_class.new(TEST_TIF_INPUT_FILE)
+        expect(object_file.send(:extension_mimetype)).to eq('image/tiff')
+      end
+    end
   end
 
-  it 'raises MiniExiftool::Error if exiftool raises one' do
-    object_file = described_class.new('spec/test_data/empty.txt')
-    expect { object_file.exif }.to raise_error(MiniExiftool::Error)
+  describe '#exif_mimetype' do
+    context 'with .tif file' do
+      it 'image/tiff' do
+        object_file = described_class.new(TEST_TIF_INPUT_FILE)
+        expect(object_file.send(:exif_mimetype)).to eq('image/tiff')
+      end
+    end
+
+    context 'when .json file' do
+      it 'nil' do
+        object_file = described_class.new(TEST_JSON_FILE)
+        expect(object_file.send(:exif_mimetype)).to be_nil
+      end
+    end
   end
 end