Fix multiple-encodings issue in dviread.PsfontsMap

Also adds a test for that function.

lib/matplotlib/dviread.py

@@ -713,31 +713,33 @@ def _register(self, words):
         There is some difference between <foo.pfb and <<bar.pfb in
         subsetting, but I have no example of << in my TeX installation.
         """
+
+        # If the map file specifies multiple encodings for a font, we
+        # follow pdfTeX in choosing the last one specified. Such
+        # entries are probably mistakes but they have occurred.
+        # http://tex.stackexchange.com/questions/10826/
+        # http://article.gmane.org/gmane.comp.tex.pdftex/4914
+
         texname, psname = words[:2]
-        effects, encodings, filename = '', [], None
+        effects, encoding, filename = '', None, None
         for word in words[2:]:
             if not word.startswith('<'):
                 effects = word
             else:
                 word = word.lstrip('<')
-                if word.startswith('['):
-                    encodings.append(word[1:])
-                elif word.endswith('.enc'):
-                    encodings.append(word)
+                if word.startswith('[') or word.endswith('.enc'):
+                    if encoding is not None:
+                        matplotlib.verbose.report(
+                            'Multiple encodings for %s = %s'
+                            % (texname, psname), 'debug')
+                    if word.startswith('['):
+                        encoding = word[1:]
+                    else:
+                        encoding = word
                 else:
                     assert filename is None
                     filename = word
 
-        if len(encodings) > 1:
-            # TODO this is a stopgap workaround, need to handle this correctly
-            matplotlib.verbose.report('Multiple encodings for %s = %s, skipping'
-                                      % (texname, psname), 'debug')
-            return
-        elif len(encodings) == 1:
-            encoding, = encodings
-        else:
-            encoding = None
-
         eff = effects.split()
         effects = {}
         try:

lib/matplotlib/tests/baseline_images/dviread/test.map

@@ -0,0 +1,10 @@
+% used by test_dviread.py
+TeXfont1 PSfont1 <font1.pfb <font1.enc
+TeXfont2 PSfont2 <font2.enc <font2.pfa
+TeXfont3 PSfont3 "1.23 UnknownEffect" <[enc3.foo <font3.pfa
+TeXfont4 PSfont4 "-0.1 SlantFont 2.2 ExtendFont" <font4.enc <font4.pfa
+TeXfont5 PSfont5 <encoding1.enc <encoding2.enc <font5.pfb
+TeXfont6 PSfont6
+TeXfont7 PSfont7 <font7.enc
+TeXfont8 PSfont8 <font8.pfb
+TeXfont9 PSfont9 </absolute/font9.pfb

lib/matplotlib/tests/test_dviread.py

@@ -0,0 +1,50 @@
+from nose.tools import assert_equal
+import matplotlib.dviread as dr
+import os.path
+
+original_find_tex_file = dr.find_tex_file
+
+def setup():
+    dr.find_tex_file = lambda x: x
+
+def teardown():
+    dr.find_tex_file = original_find_tex_file
+
+def test_PsfontsMap():
+    filename = os.path.join(
+        os.path.dirname(__file__),
+        'baseline_images', 'dviread', 'test.map')
+    fontmap = dr.PsfontsMap(filename)
+    # Check all properties of a few fonts
+    for n in [1, 2, 3, 4, 5]:
+        key = 'TeXfont%d' % n
+        entry = fontmap[key]
+        assert_equal(entry.texname, key)
+        assert_equal(entry.psname, 'PSfont%d' % n)
+        if n not in [3, 5]:
+            assert_equal(entry.encoding, 'font%d.enc' % n)
+        elif n == 3:
+            assert_equal(entry.encoding, 'enc3.foo')
+        # We don't care about the encoding of TeXfont5, which specifies
+        # multiple encodings.
+        if n not in [1, 5]:
+            assert_equal(entry.filename, 'font%d.pfa' % n)
+        else:
+            assert_equal(entry.filename, 'font%d.pfb' % n)
+        if n == 4:
+            assert_equal(entry.effects, {'slant': -0.1, 'extend': 2.2})
+        else:
+            assert_equal(entry.effects, {})
+    # Some special cases
+    entry = fontmap['TeXfont6']
+    assert_equal(entry.filename, None)
+    assert_equal(entry.encoding, None)
+    entry = fontmap['TeXfont7']
+    assert_equal(entry.filename, None)
+    assert_equal(entry.encoding, 'font7.enc')
+    entry = fontmap['TeXfont8']
+    assert_equal(entry.filename, 'font8.pfb')
+    assert_equal(entry.encoding, None)
+    entry = fontmap['TeXfont9']
+    assert_equal(entry.filename, '/absolute/font9.pfb')
+