From 71a35aa4963c569f4b1dd1530c19ea622df19a8e Mon Sep 17 00:00:00 2001
From: Just van Rossum <justvanrossum@gmail.com>
Date: Fri, 27 Mar 2020 19:40:02 +0100
Subject: [PATCH] Reproduce crash on Windows? (#37)

Keep a reference to the data blob to avoid HB looking at GC-ed memory. This avoids bad gids and crashes in some environments if the user code doesn't hold on to the blob itself.
---
 src/uharfbuzz/_harfbuzz.pyx | 2 ++
 tests/test_uharfbuzz.py     | 4 ++--
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/uharfbuzz/_harfbuzz.pyx b/src/uharfbuzz/_harfbuzz.pyx
index 33d796d..654062f 100644
--- a/src/uharfbuzz/_harfbuzz.pyx
+++ b/src/uharfbuzz/_harfbuzz.pyx
@@ -264,10 +264,12 @@ cdef hb_blob_t* _reference_table_func(
 cdef class Face:
     cdef hb_face_t* _hb_face
     cdef object _reference_table_func
+    cdef object _blob
 
     def __cinit__(self, bytes blob, int index=0):
         cdef hb_blob_t* hb_blob
         if blob is not None:
+            self._blob = blob
             hb_blob = hb_blob_create(
                 blob, len(blob), HB_MEMORY_MODE_READONLY, NULL, NULL)
             self._hb_face = hb_face_create(hb_blob, index)
diff --git a/tests/test_uharfbuzz.py b/tests/test_uharfbuzz.py
index e58e00e..cb122ef 100644
--- a/tests/test_uharfbuzz.py
+++ b/tests/test_uharfbuzz.py
@@ -4,7 +4,7 @@
 
 
 TESTDATA = Path(__file__).parent / "data"
-ADOBE_BLANK_TTF = (TESTDATA / "AdobeBlank.subset.ttf").read_bytes()
+ADOBE_BLANK_TTF_PATH = TESTDATA / "AdobeBlank.subset.ttf"
 
 
 @pytest.fixture
@@ -22,7 +22,7 @@ def blankfont():
         {gid=8, name="u1F4A9", code=0x1F4A9},  # PILE OF POO
     ]
     """
-    face = hb.Face(ADOBE_BLANK_TTF)
+    face = hb.Face(ADOBE_BLANK_TTF_PATH.read_bytes())
     font = hb.Font(face)
     upem = face.upem
     font.scale = (upem, upem)