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

core/src/fxcrt/fx_basic_wstring_unittest.cpp

Index: core/src/fxcrt/fx_basic_wstring_unittest.cpp
diff --git a/core/src/fxcrt/fx_basic_wstring_unittest.cpp b/core/src/fxcrt/fx_basic_wstring_unittest.cpp
index 3b15006d655f8019f6906406d8147d09bd271af7..ee010f281898e02d773c2d3fa61bc382c41517c5 100644
--- a/core/src/fxcrt/fx_basic_wstring_unittest.cpp
+++ b/core/src/fxcrt/fx_basic_wstring_unittest.cpp
@@ -6,6 +6,23 @@
 #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");
@@ -170,6 +187,23 @@ TEST(fxcrt, WideStringUTF16LE_Encode) {
   }
 }
 
+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");