Cleanup some numeric code.

This changes the various comparisons of char >= '0' && char <= '9' and
char < '0' || char > '9' to use std::isdigit checks. It also cleans up
a handful of hex to digit conversions to call one common method.

R=thestig@chromium.org

Review URL: https://codereview.chromium.org/1415933005 .

1 files changed, 14 insertions, 0 deletions

diff --git a/core/src/fxcrt/fx_extension_unittest.cpp b/core/src/fxcrt/fx_extension_unittest.cpp
new file mode 100644
index 0000000000..e2017fc3ed
--- /dev/null
+++ b/core/src/fxcrt/fx_extension_unittest.cpp
@@ -0,0 +1,14 @@
+// Copyright 2015 PDFium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "testing/gtest/include/gtest/gtest.h"
+
+#include "../../include/fxcrt/fx_ext.h"
+
+TEST(fxcrt, HexCharToDigit) {
+  EXPECT_EQ(10, HexCharToDigit('a'));
+  EXPECT_EQ(10, HexCharToDigit('A'));
+  EXPECT_EQ(7, HexCharToDigit('7'));
+  EXPECT_EQ(0, HexCharToDigit('i'));
+}