1 files changed, 43 insertions, 0 deletions
diff --git a/intl/components/src/LocaleCanonicalizer.h b/intl/components/src/LocaleCanonicalizer.h
new file mode 100644
index 0000000000..bd17c9dfd4
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+++ b/intl/components/src/LocaleCanonicalizer.h
@@ -0,0 +1,43 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+#ifndef intl_components_LocaleCanonicalizer_h_
+#define intl_components_LocaleCanonicalizer_h_
+
+#include "mozilla/intl/ICU4CGlue.h"
+#include "mozilla/Span.h"
+#include "mozilla/Vector.h"
+
+namespace mozilla::intl {
+
+/**
+ * 32 is somewhat an arbitrary size, but it should fit most locales on the
+ * stack to avoid heap allocations.
+ */
+constexpr size_t INITIAL_LOCALE_CANONICALIZER_BUFFER_SIZE = 32;
+
+/**
+ * Eventually this class will unify the behaviors of Locale Canonicalization.
+ * See Bug 1723586.
+ */
+class LocaleCanonicalizer {
+ public:
+  using Vector =
+      mozilla::Vector<char, INITIAL_LOCALE_CANONICALIZER_BUFFER_SIZE>;
+
+  /**
+   * This static method will canonicalize a locale string, per the Level 1
+   * canonicalization steps outlined in:
+   * http://userguide.icu-project.org/locale#TOC-Canonicalization
+   *
+   * For instance it will turn the string "en-US" to "en_US". It guarantees that
+   * the string span targeted will be in the ASCII range. The canonicalization
+   * process on ICU is somewhat permissive in what it accepts as input, but only
+   * ASCII locales are technically correct.
+   */
+  static ICUResult CanonicalizeICULevel1(
+      const char* aLocale, LocaleCanonicalizer::Vector& aLocaleOut);
+};
+
+}  // namespace mozilla::intl
+#endif