From 350cc702f1e9499d621472f05898a03b493ce52a Mon Sep 17 00:00:00 2001
From: wiredfool <eric-github@soroos.net>
Date: Mon, 7 Oct 2013 23:01:15 -0700
Subject: [PATCH] Additional tests for reading and writing Tiff
 ImageFileDirectories

---
 Tests/test_file_libtiff.py       | 21 ++++++++++-
 Tests/test_file_tiff_metadata.py | 61 +++++++++++++++++++++++++++++---
 2 files changed, 77 insertions(+), 5 deletions(-)

diff --git a/Tests/test_file_libtiff.py b/Tests/test_file_libtiff.py
index 037fc022d..976f97f34 100644
--- a/Tests/test_file_libtiff.py
+++ b/Tests/test_file_libtiff.py
@@ -92,7 +92,6 @@ def test_g4_write():
     assert_equal(reread.size,(500,500))
     _assert_noerr(reread)
     assert_image_equal(reread, rot)
-
     assert_false(orig.tobytes() == reread.tobytes())
 
 def test_adobe_deflate_tiff():
@@ -105,3 +104,23 @@ def test_adobe_deflate_tiff():
     assert_no_exception(lambda: im.load())
 
 
+def test_write_metadata():
+    """ Test metadata writing through libtiff """
+    img = Image.open('Tests/images/lena_g4.tif')
+    f = tempfile('temp.tiff')
+    img.save(f, tiffinfo = img.tag)
+
+    loaded = Image.open(f)
+
+    original = img.tag.named()
+    reloaded = loaded.tag.named()
+
+    ignored = ['StripByteCounts', 'RowsPerStrip', 'PageNumber']
+    
+    for tag, value in reloaded.items():
+        if tag not in ignored:
+            assert_equal(original[tag], value, "%s didn't roundtrip" % tag)
+
+    for tag, value in original.items():
+        if tag not in ignored: 
+            assert_equal(value, reloaded[tag], "%s didn't roundtrip" % tag)
diff --git a/Tests/test_file_tiff_metadata.py b/Tests/test_file_tiff_metadata.py
index 8c38a1cb6..9a050e1e3 100644
--- a/Tests/test_file_tiff_metadata.py
+++ b/Tests/test_file_tiff_metadata.py
@@ -3,11 +3,12 @@ from PIL import Image, TiffImagePlugin, TiffTags
 
 tag_ids = dict(zip(TiffTags.TAGS.values(), TiffTags.TAGS.keys()))
 
-# Test writing arbitray metadata into the tiff image directory
-# Use case is ImageJ private tags, one numeric, one arbitrary data.
-# https://github.com/python-imaging/Pillow/issues/291
-
 def test_rt_metadata():
+    """ Test writing arbitray metadata into the tiff image directory
+        Use case is ImageJ private tags, one numeric, one arbitrary
+        data.  https://github.com/python-imaging/Pillow/issues/291
+        """
+    
     img = lena()
 
     textdata = "This is some arbitrary metadata for a text field"
@@ -25,3 +26,55 @@ def test_rt_metadata():
     assert_equal(loaded.tag[50838], (len(textdata),))
     assert_equal(loaded.tag[50839], textdata)
     
+def test_read_metadata():
+    img = Image.open('Tests/images/lena_g4.tif')
+    
+    known = {'YResolution': ((1207959552, 16777216),),
+             'PlanarConfiguration': (1,),
+             'BitsPerSample': (1,),
+             'ImageLength': (128,),
+             'Compression': (4,),
+             'FillOrder': (1,),
+             'DocumentName': u'lena.g4.tif',
+             'RowsPerStrip': (128,),
+             'ResolutionUnit': (1,),
+             'PhotometricInterpretation': (0,),
+             'PageNumber': (0, 1),
+             'XResolution': ((1207959552, 16777216),),
+             'ImageWidth': (128,),
+             'Orientation': (1,),
+             'StripByteCounts': (1796,),
+             'SamplesPerPixel': (1,),
+             'StripOffsets': (8,),
+             'Software': u'ImageMagick 6.5.7-8 2012-08-17 Q16 http://www.imagemagick.org'}
+
+    # assert_equal is equivalent, but less helpful in telling what's wrong. 
+    named = img.tag.named()
+    for tag, value in named.items():
+        assert_equal(known[tag], value)
+
+    for tag, value in known.items():
+        assert_equal(value, named[tag])
+
+
+def test_write_metadata():
+    """ Test metadata writing through the python code """
+    img = Image.open('Tests/images/lena.tif')
+
+    f = tempfile('temp.tiff')
+    img.save(f, tiffinfo = img.tag)
+
+    loaded = Image.open(f)
+
+    original = img.tag.named()
+    reloaded = loaded.tag.named()
+
+    ignored = ['StripByteCounts', 'RowsPerStrip', 'PageNumber', 'StripOffsets']
+    
+    for tag, value in reloaded.items():
+        if tag not in ignored:
+            assert_equal(original[tag], value, "%s didn't roundtrip" % tag)
+
+    for tag, value in original.items():
+        if tag not in ignored: 
+            assert_equal(value, reloaded[tag], "%s didn't roundtrip" % tag)