Add tests for charset aware PcfFontFile

Tests/fonts/LICENSE.txt

@@ -4,6 +4,7 @@ NotoSansJP-Thin.otf, from https://www.google.com/get/noto/help/cjk/
 AdobeVFPrototype.ttf, from https://github.com/adobe-fonts/adobe-variable-font-prototype
 TINY5x3GX.ttf, from http://velvetyne.fr/fonts/tiny
 ArefRuqaa-Regular.ttf, from https://github.com/google/fonts/tree/master/ofl/arefruqaa
+ter-x20b.pcf, from http://terminus-font.sourceforge.net/
 
 All of the above fonts are published under the SIL Open Font License (OFL) v1.1 (http://scripts.sil.org/cms/scripts/page.php?site_id=nrsi&id=OFL), which allows you to copy, modify, and redistribute them if you need to.
 

Tests/test_font_pcf_charsets.py

@@ -0,0 +1,129 @@
+# -*- coding: UTF-8 -*-
+from .helper import PillowTestCase
+
+from PIL import Image, FontFile, PcfFontFile
+from PIL import ImageFont, ImageDraw
+
+# from PIL._util import py3
+
+codecs = dir(Image.core)
+
+fontname = "Tests/fonts/ter-x20b.pcf"
+
+charsets = {
+    "iso8859-1": {
+        "glyph_count": 223,
+        "message": u"hello, world",
+        "image1": "Tests/images/test_draw_pbm_ter_en_target.png",
+    },
+    "iso8859-2": {
+        "glyph_count": 223,
+        "message": u"witaj świecie",
+        "image1": "Tests/images/test_draw_pbm_ter_pl_target.png",
+    },
+    "cp1250": {
+        "glyph_count": 250,
+        "message": u"witaj świecie",
+        "image1": "Tests/images/test_draw_pbm_ter_pl_target.png",
+    },
+}
+
+
+class TestFontPcf(PillowTestCase):
+    def setUp(self):
+        if "zip_encoder" not in codecs or "zip_decoder" not in codecs:
+            self.skipTest("zlib support not available")
+
+    def save_font(self, encoding):
+        with open(fontname, "rb") as test_file:
+            font = PcfFontFile.PcfFontFile(test_file, encoding)
+        self.assertIsInstance(font, FontFile.FontFile)
+        # check the number of characters in the font
+        self.assertEqual(
+            len([_f for _f in font.glyph if _f]), charsets[encoding]["glyph_count"]
+        )
+
+        tempname = self.tempfile("temp.pil")
+        self.addCleanup(self.delete_tempfile, tempname[:-4] + ".pbm")
+        font.save(tempname)
+
+        with Image.open(tempname.replace(".pil", ".pbm")) as loaded:
+            with Image.open("Tests/fonts/ter-x20b-%s.pbm" % encoding) as target:
+                self.assert_image_equal(loaded, target)
+
+        with open(tempname, "rb") as f_loaded:
+            with open("Tests/fonts/ter-x20b-%s.pil" % encoding, "rb") as f_target:
+                self.assertEqual(f_loaded.read(), f_target.read())
+        return tempname
+
+    def _test_sanity(self, encoding):
+        self.save_font(encoding)
+
+    def test_sanity_iso8859_1(self):
+        self._test_sanity("iso8859-1")
+
+    def test_sanity_iso8859_2(self):
+        self._test_sanity("iso8859-2")
+
+    def test_sanity_cp1250(self):
+        self._test_sanity("cp1250")
+
+    # def test_invalid_file(self):
+    #     with open("Tests/images/flower.jpg", "rb") as fp:
+    #         self.assertRaises(SyntaxError, PcfFontFile.PcfFontFile, fp)
+
+    def _test_draw(self, encoding):
+        tempname = self.save_font(encoding)
+        font = ImageFont.load(tempname)
+        im = Image.new("L", (150, 30), "white")
+        draw = ImageDraw.Draw(im)
+        message = charsets[encoding]["message"].encode(encoding)
+        draw.text((0, 0), message, "black", font=font)
+        with Image.open(charsets[encoding]["image1"]) as target:
+            self.assert_image_similar(im, target, 0)
+
+    def test_draw_iso8859_1(self):
+        self._test_draw("iso8859-1")
+
+    def test_draw_iso8859_2(self):
+        self._test_draw("iso8859-2")
+
+    def test_draw_cp1250(self):
+        self._test_draw("cp1250")
+
+    def _test_textsize(self, encoding):
+        tempname = self.save_font(encoding)
+        font = ImageFont.load(tempname)
+        for i in range(255):
+            (dx, dy) = font.getsize(bytearray([i]))
+            self.assertEqual(dy, 20)
+            self.assertIn(dx, (0, 10))
+        message = charsets[encoding]["message"].encode(encoding)
+        for l in range(len(message)):
+            msg = message[: l + 1]
+            self.assertEqual(font.getsize(msg), (len(msg) * 10, 20))
+
+    def test_textsize_iso8859_1(self):
+        self._test_textsize("iso8859-1")
+
+    def test_textsize_iso8859_2(self):
+        self._test_textsize("iso8859-2")
+
+    def test_textsize_cp1250(self):
+        self._test_textsize("cp1250")
+
+    # def _test_high_characters(self, message, encoding):
+    #     tempname = self.save_font(encoding)
+    #     font = ImageFont.load(tempname)
+    #     im = Image.new("L", (750, 30), "white")
+    #     draw = ImageDraw.Draw(im)
+    #     draw.text((0, 0), message, "black", font=font)
+    #     with Image.open("Tests/images/high_ascii_chars.png") as target:
+    #         self.assert_image_similar(im, target, 0)
+    #
+    # def test_high_characters(self):
+    #     message = "".join(chr(i + 1) for i in range(140, 232))
+    #     self._test_high_characters(message)
+    #     # accept bytes instances in Py3.
+    #     if py3:
+    #         self._test_high_characters(message.encode("latin1"))