Make constructors recognize char[n] vs. char* and avoid strlen calls.

core/src/fxcrt/fx_basic_wstring_unittest.cpp

 // Copyright 2014 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 "../../../testing/fx_string_testhelpers.h"
 #include "../../include/fxcrt/fx_basic.h"
 
+TEST(fxcrt, WideStringNotNull) {
+    // Prove constructor uses sizeof(), not strlen() against literals.
+    CFX_WideString literal_string(L"ab\0c");
+    EXPECT_EQ(4, literal_string.GetLength());
+
+    // Prove constructor uses strlen(), not sizeof() against mutable arrays.
+    wchar_t array[32];
+    memcpy(array, L"ab\0c", 5 * sizeof(wchar_t));
+    CFX_WideString array_string(array);
+    EXPECT_EQ(2, array_string.GetLength());
+
+    // Prove constructor uses strlen(), not sizeof() against pointers.
+    const wchar_t* ptr = L"ab\0c";
+    CFX_WideString pointer_string(ptr);
+    EXPECT_EQ(2, pointer_string.GetLength());
+}
+
 TEST(fxcrt, WideStringOperatorSubscript) {
     // CFX_WideString includes the NUL terminator for non-empty strings.
     CFX_WideString abc(L"abc");
     EXPECT_EQ(L'a', abc[0]);
     EXPECT_EQ(L'b', abc[1]);
     EXPECT_EQ(L'c', abc[2]);
     EXPECT_EQ(L'\0', abc[3]);
 }
 
 TEST(fxcrt, WideStringOperatorLT) {
@@ skipping 144 matching lines @@
     { L"\x3132\x6162", ByteStringLiteral("\x32\x31\x62\x61\0\0") },
   };
 
   for (size_t i = 0; i < FX_ArraySize(utf16le_encode_cases); ++i) {
     EXPECT_EQ(utf16le_encode_cases[i].bs,
         utf16le_encode_cases[i].ws.UTF16LE_Encode())
         << " for case number " << i;
   }
 }
 
+TEST(fxcrt, WideStringCNotNull) {
+    // Prove constructor uses sizeof(), not strlen() against literals.
+    CFX_WideStringC literal_string(L"ab\0c");
+    EXPECT_EQ(4, literal_string.GetLength());
+
+    // Prove constructor uses strlen(), not sizeof() against mutable arrays.
+    wchar_t array[32];
+    memcpy(array, L"ab\0c", 5 * sizeof(wchar_t));
+    CFX_WideStringC array_string(array);
+    EXPECT_EQ(2, array_string.GetLength());
+
+    // Prove constructor uses strlen(), not sizeof() against pointers.
+    const wchar_t* ptr = L"ab\0c";
+    CFX_WideStringC pointer_string(ptr);
+    EXPECT_EQ(2, pointer_string.GetLength());
+}
+
 TEST(fxcrt, WideStringCOperatorSubscript) {
     // CFX_WideStringC includes the NUL terminator for non-empty strings.
     CFX_WideStringC abc(L"abc");
     EXPECT_EQ(L'a', abc[0]);
     EXPECT_EQ(L'b', abc[1]);
     EXPECT_EQ(L'c', abc[2]);
     EXPECT_EQ(L'\0', abc[3]);
 }
 
 TEST(fxcrt, WideStringCOperatorLT) {
@@ skipping 122 matching lines @@
     const wchar_t* c_string2 = L"hellp";
     const wchar_t* c_string3 = L"hellod";
     ASSERT_TRUE(wide_string_c != c_string1);
     ASSERT_TRUE(wide_string_c != c_string2);
     ASSERT_TRUE(wide_string_c != c_string3);
 
     ASSERT_TRUE(c_string1 != wide_string_c);
     ASSERT_TRUE(c_string2 != wide_string_c);
     ASSERT_TRUE(c_string3 != wide_string_c);
 }