Case folding mappings

test/cctest/test-regexp.cc

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 689 matching lines @@
   ranges->Add(CharacterRange(0xFFF0, 0xFFFE));
   DispatchTable table;
   DispatchTableConstructor cons(&table);
   cons.set_choice_index(0);
   cons.AddInverse(ranges);
   CHECK(!table.Get(0xFFFE)->Get(0));
   CHECK(table.Get(0xFFFF)->Get(0));
 }
 
 
+static uc32 canonicalize(uc32 c) {
+  unibrow::uchar canon[unibrow::kMaxMappingSize];
+  int count = unibrow::Ecma262Canonicalize::Convert(c, '\0', canon, NULL);
+  if (count == 0) {
+    return c;
+  } else {
+    CHECK_EQ(1, count);
+    return canon[0];
+  }
+}
+
+
+TEST(LatinCanonicalize) {
+  unibrow::Mapping<unibrow::Ecma262UnCanonicalize> un_canonicalize;
+  for (char lower = 'a'; lower <= 'z'; lower++) {
+    char upper = lower + ('A' - 'a');

[Lasse Reichstein, 2008/11/17 10:30:42]

Would it be reasonable to check every code point in the range 0..0xffff, to see
that it agrees with toUpperCase?

[Christian Plesner Hansen, 2008/11/17 10:47:33]

Certainly would; I've added it.

+    CHECK_EQ(canonicalize(lower), canonicalize(upper));
+    unibrow::uchar uncanon[unibrow::kMaxMappingSize];
+    int length = un_canonicalize.get(lower, '\0', uncanon);
+    CHECK_EQ(2, length);
+    CHECK_EQ(upper, uncanon[0]);
+    CHECK_EQ(lower, uncanon[1]);
+  }
+  for (uc32 c = 128; c < (1 << 21); c++) {
+    // These exceptions are caused by a known bug in the implementation.
+    if (c != 0x026B && c != 0x027D)
+      CHECK(canonicalize(c) >= 128);
+  }
+}
+
+
 TEST(Graph) {
   Execute("fo[ob]ar|[ba]z|x[yz]*", "", true);
 }