[subset] Add some helper functions for writing tests around subsetting.

test/api/Makefile.am

@@ -16,7 +16,7 @@ if HAVE_GLIB
 AM_CPPFLAGS = -DSRCDIR="\"$(srcdir)\"" -I$(top_srcdir)/src/ -I$(top_builddir)/src/ $(GLIB_CFLAGS)
 LDADD = $(top_builddir)/src/libharfbuzz.la $(GLIB_LIBS)
 
-EXTRA_DIST += hb-test.h
+EXTRA_DIST += hb-test.h hb-subset-test.h
 
 check_PROGRAMS = $(TEST_PROGS)
 noinst_PROGRAMS = $(TEST_PROGS)

test/api/hb-subset-test.h

@@ -0,0 +1,123 @@
+/*
+ * Copyright © 2018  Google, Inc.
+ *
+ *  This is part of HarfBuzz, a text shaping library.
+ *
+ * Permission is hereby granted, without written agreement and without
+ * license or royalty fees, to use, copy, modify, and distribute this
+ * software and its documentation for any purpose, provided that the
+ * above copyright notice and the following two paragraphs appear in
+ * all copies of this software.
+ *
+ * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
+ * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
+ * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
+ * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
+ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+ *
+ * Google Author(s): Garret Rieger
+ */
+
+#ifndef HB_SUBSET_TEST_H
+#define HB_SUBSET_TEST_H
+
+#include <stdio.h>
+
+#include "hb-test.h"
+
+
+HB_BEGIN_DECLS
+
+static inline char *
+hb_subset_test_read_file (const char *path,
+                          size_t     *length /* OUT */)
+{
+  FILE *fp = fopen (path, "rb");
+
+  size_t file_length = 0;
+  char *buffer = NULL;
+  if (fp && fseek (fp, 0, SEEK_END) == 0) {
+    file_length = ftell(fp);
+    rewind (fp);
+  }
+
+  if (file_length > 0) {
+    buffer = (char *) calloc (file_length + 1, sizeof(char));
+    if (fread (buffer, 1, file_length, fp) == file_length) {
+      *length = file_length;
+    } else {
+      free (buffer);
+      buffer = NULL;
+    }
+  }
+
+  if (fp)
+    fclose(fp);
+
+  return buffer;
+}
+
+static inline hb_face_t *
+hb_subset_test_open_font (const char *font_path)
+{
+#if GLIB_CHECK_VERSION(2,37,2)
+  gchar* path = g_test_build_filename(G_TEST_DIST, font_path, NULL);
+#else
+  gchar* path = g_strdup(fontFile);
+#endif
+
+  size_t length;
+  char *font_data = hb_subset_test_read_file(path, &length);
+
+  if (font_data != NULL) {
+    hb_blob_t *blob = hb_blob_create (font_data,
+                                      length,
+                                      HB_MEMORY_MODE_READONLY,
+                                      font_data,
+                                      free);
+    hb_face_t *face = hb_face_create (blob, 0);
+    hb_blob_destroy (blob);
+    return face;
+  }
+
+  return NULL;
+}
+
+static inline hb_face_t *
+hb_subset_test_create_subset (hb_face_t *source,
+                              hb_set_t  *codepoints)
+{
+  hb_subset_profile_t *profile = hb_subset_profile_create();
+  hb_subset_input_t *input = hb_subset_input_create (codepoints);
+  hb_face_t *subset = hb_subset (source, profile, input);
+  g_assert (subset);
+
+  hb_subset_profile_destroy (profile);
+  hb_subset_input_destroy (input);
+  return subset;
+}
+
+static inline void
+hb_subset_test_check (hb_face_t *expected,
+                      hb_face_t *actual,
+                      hb_tag_t   table)
+{
+  hb_blob_t *glyf_expected_blob = hb_face_reference_table (expected, table);
+  hb_blob_t *glyf_actual_blob = hb_face_reference_table (actual, table);
+  int expected_length, actual_length;
+  g_assert_cmpmem(hb_blob_get_data (glyf_expected_blob, &expected_length), expected_length,
+                  hb_blob_get_data (glyf_actual_blob, &actual_length), actual_length);
+  hb_blob_destroy (glyf_actual_blob);
+  hb_blob_destroy (glyf_expected_blob);
+}
+
+
+HB_END_DECLS
+
+#endif /* HB_SUBSET_TEST_H */