From fb050c7a7fda0a44b4b9c2b4ce97553e54b7d60f Mon Sep 17 00:00:00 2001
From: Sascha Brawer <sascha@brawer.ch>
Date: Tue, 11 Aug 2015 16:45:54 +0200
Subject: [PATCH] [feaLib] Parse rules for multiple substitution (GSUB
 LookupType 2)

---
 Lib/fontTools/feaLib/parser.py      |  5 +++--
 Lib/fontTools/feaLib/parser_test.py | 10 ++++++++++
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/Lib/fontTools/feaLib/parser.py b/Lib/fontTools/feaLib/parser.py
index 45d09210f..6292edec0 100644
--- a/Lib/fontTools/feaLib/parser.py
+++ b/Lib/fontTools/feaLib/parser.py
@@ -219,15 +219,16 @@ class Parser(object):
         location = self.cur_token_location_
         old_prefix, old, lookups, old_suffix = self.parse_glyph_pattern_()
 
+        new = []
         if self.next_token_ == "by":
             keyword = self.expect_keyword_("by")
-            new = [self.parse_glyphclass_(accept_glyphname=True)]
+            while self.next_token_ != ";":
+                new.append(self.parse_glyphclass_(accept_glyphname=True))
         elif self.next_token_ == "from":
             keyword = self.expect_keyword_("from")
             new = [self.parse_glyphclass_(accept_glyphname=False)]
         else:
             keyword = None
-            new = []
         self.expect_symbol_(";")
         if len(new) is 0 and not any(lookups):
             raise ParserError(
diff --git a/Lib/fontTools/feaLib/parser_test.py b/Lib/fontTools/feaLib/parser_test.py
index 6bb8bc0de..9de5d9362 100644
--- a/Lib/fontTools/feaLib/parser_test.py
+++ b/Lib/fontTools/feaLib/parser_test.py
@@ -289,6 +289,16 @@ class ParserTest(unittest.TestCase):
         self.assertEqual(sub.new, [{"A.sc", "B.sc", "C.sc", "D.sc"}])
         self.assertEqual(sub.lookups, [None])
 
+    def test_substitute_multiple(self):  # GSUB LookupType 2
+        doc = self.parse("lookup Look {substitute f_f_i by f f i;} Look;")
+        sub = doc.statements[0].statements[0]
+        self.assertEqual(type(sub), ast.SubstitutionRule)
+        self.assertEqual(sub.old_prefix, [])
+        self.assertEqual(sub.old, [{"f_f_i"}])
+        self.assertEqual(sub.old_suffix, [])
+        self.assertEqual(sub.new, [{"f"}, {"f"}, {"i"}])
+        self.assertEqual(sub.lookups, [None])
+
     def test_substitute_from(self):  # GSUB LookupType 3
         doc = self.parse("feature test {"
                          "  substitute a from [a.1 a.2 a.3];"