Use span in CXFA_LocaleValue::GetDoubleNum()chromium/3399

Get runtime checks instead of just asserts.
Use early return while at it to save some indentation.
Fix one out-of-bounds case noted by inspection.
Add tests, and fix bugs that gave the wrong answers.

This should be removed at our earliest convenience. Its likely to
still be wrong.

Change-Id: I2a68edc854c8b28c434fe28397b7834e5c9c3670
Reviewed-on: https://pdfium-review.googlesource.com/30530
Commit-Queue: Tom Sepez <tsepez@chromium.org>
Reviewed-by: dsinclair <dsinclair@chromium.org>

1 files changed, 37 insertions, 0 deletions

diff --git a/xfa/fxfa/parser/cxfa_localevalue_unittest.cpp b/xfa/fxfa/parser/cxfa_localevalue_unittest.cpp
new file mode 100644
index 0000000000..5b97eb3785
--- /dev/null
+++ b/xfa/fxfa/parser/cxfa_localevalue_unittest.cpp
@@ -0,0 +1,37 @@
+// Copyright 2018 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 "xfa/fxfa/parser/cxfa_localevalue.h"
+
+#include "testing/gtest/include/gtest/gtest.h"
+#include "testing/test_support.h"
+
+namespace {
+
+// We don't expect more precision than a float's worth from this code.
+float MakeDoubleNumAsFloat(const wchar_t* str) {
+  return static_cast<float>(
+      CXFA_LocaleValue(XFA_VT_FLOAT, str, nullptr).GetDoubleNum());
+}
+
+}  // namespace
+
+TEST(CXFALocaleValueTest, GetDoubleNum) {
+  EXPECT_EQ(0.0, MakeDoubleNumAsFloat(L""));
+  EXPECT_EQ(0.0, MakeDoubleNumAsFloat(L"0"));
+  EXPECT_EQ(0.0, MakeDoubleNumAsFloat(L"0."));
+  EXPECT_EQ(0.0, MakeDoubleNumAsFloat(L"0.0"));
+  EXPECT_EQ(0.0, MakeDoubleNumAsFloat(L"0.x"));
+  EXPECT_EQ(7.0, MakeDoubleNumAsFloat(L"7.x"));
+  EXPECT_FLOAT_EQ(0.54321f, MakeDoubleNumAsFloat(L".54321"));
+  EXPECT_FLOAT_EQ(0.54321f, MakeDoubleNumAsFloat(L"0.54321"));
+  EXPECT_FLOAT_EQ(0.54321f, MakeDoubleNumAsFloat(L"+0.54321"));
+  EXPECT_FLOAT_EQ(0.54321f, MakeDoubleNumAsFloat(L"   +0.54321"));
+  EXPECT_FLOAT_EQ(-0.54321f, MakeDoubleNumAsFloat(L"-.54321"));
+  EXPECT_FLOAT_EQ(-0.54321f, MakeDoubleNumAsFloat(L"-0.54321"));
+  EXPECT_FLOAT_EQ(-0.54321f, MakeDoubleNumAsFloat(L"  -0.54321"));
+  EXPECT_FLOAT_EQ(-0.054321f, MakeDoubleNumAsFloat(L"-0.54321e-1"));
+  EXPECT_FLOAT_EQ(-0.54321f, MakeDoubleNumAsFloat(L"-0.54321e0"));
+  EXPECT_FLOAT_EQ(-5.4321f, MakeDoubleNumAsFloat(L"-0.54321e1"));
+}