update tests handling

src/tests/__init__.py

@@ -1,7 +1,103 @@
 import unittest
-import test_img2pdf
+
+import datetime
+import os
+import unittest
+import img2pdf
+import zlib
+from PIL import Image
+
+HERE = os.path.dirname(__file__)
+
+#convert +set date:create +set date:modify -define png:exclude-chunk=time
 
 def test_suite():
+    class TestImg2Pdf(unittest.TestCase):
+        pass
+
+    for test_name in os.listdir(os.path.join(HERE, "input")):
+        inputf = os.path.join(HERE, "input", test_name)
+        if not os.path.isfile(inputf):
+            continue
+        outputf = os.path.join(HERE, "output", test_name+".pdf")
+        assert os.path.isfile(outputf)
+        def handle(self, f=inputf, out=outputf):
+            with open(f, "rb") as inf:
+                orig_imgdata = inf.read()
+            pdf = img2pdf.convert([f], nodate=True)
+            imgdata = b""
+            instream = False
+            imgobj = False
+            colorspace = None
+            imgfilter = None
+            width = None
+            height = None
+            length = None
+            # ugly workaround to parse the created pdf
+            for line in pdf.split(b'\n'):
+                if instream:
+                    if line == b"endstream":
+                        break
+                    else:
+                        imgdata += line + b'\n'
+                else:
+                    if imgobj and line == b"stream":
+                        instream = True
+                    elif b"/Subtype /Image" in line:
+                        imgobj = True
+                    elif b"/Width" in line:
+                        width = int(line.split()[-1])
+                    elif b"/Height" in line:
+                        height = int(line.split()[-1])
+                    elif b"/Length" in line:
+                        length = int(line.split()[-1])
+                    elif b"/Filter" in line:
+                        imgfilter = line.split()[-2]
+                    elif b"/ColorSpace" in line:
+                        colorspace = line.split()[-1]
+            # remove trailing \n
+            imgdata = imgdata[:-1]
+            # test if the length field is correct
+            self.assertEqual(len(imgdata), length)
+            # test if the filter is valid:
+            self.assertIn(imgfilter, [b"/DCTDecode", b"/JPXDecode", b"/FlateDecode"])
+            # test if the colorspace is valid
+            self.assertIn(colorspace, [b"/DeviceGray", b"/DeviceRGB", b"/DeviceCMYK"])
+            # test if the image has correct size
+            orig_img = Image.open(f)
+            self.assertEqual(width, orig_img.size[0])
+            self.assertEqual(height, orig_img.size[1])
+            # if the input file is a jpeg then it should've been copied
+            # verbatim into the PDF
+            if imgfilter in [b"/DCTDecode", b"/JPXDecode"]:
+                self.assertEqual(imgdata, orig_imgdata)
+            elif imgfilter == b"/FlateDecode":
+                # otherwise, the data is flate encoded and has to be equal to
+                # the pixel data of the input image
+                imgdata = zlib.decompress(imgdata)
+                if colorspace == b"/DeviceGray":
+                    colorspace = 'L'
+                elif colorspace == b"/DeviceRGB":
+                    colorspace = 'RGB'
+                elif colorspace == b"/DeviceCMYK":
+                    colorspace = 'CMYK'
+                else:
+                    raise Exception("invalid colorspace")
+                im = Image.frombytes(colorspace, (width, height), imgdata)
+                if orig_img.mode == '1':
+                    orig_img = orig_img.convert("L")
+                elif orig_img.mode not in ("RGB", "L", "CMYK", "CMYK;I"):
+                    orig_img = orig_img.convert("RGB")
+                self.assertEqual(im.tobytes(), orig_img.tobytes())
+                im.close()
+            # lastly, make sure that the generated pdf matches bit by bit the
+            # expected pdf
+            with open(out, "rb") as outf:
+                out = outf.read()
+            self.assertEqual(pdf, out)
+            orig_img.close()
+        setattr(TestImg2Pdf, "test_%s"%test_name, handle)
+
     return unittest.TestSuite((
-            unittest.makeSuite(test_img2pdf.TestImg2Pdf),
+            unittest.makeSuite(TestImg2Pdf),
             ))