[FR]: Trying to use std::filesystem::path as a type for testing::TestWithParam results in an endless recursion.

[b068931]

Does the feature exist in the most recent commit?

Either I didn't look hard enough or it does not exist in the most recent commit. At least, the version that Visual Studio uses has this problem. I looked in "gtest-printers.h".

Why do we need this feature?

Google Test supports C++17 as far as I understand. And std::filesystem::path is a type which can theoretically be used for tests against different files, so I would expect it work properly or fail with a meaningful message.

Describe the proposal.

The code gets stuck in a loop: UniversalPrint -> UniversalPrinter -> PrintTo -> DefaultPrintTo -> UniversalPrint until a stackoverflow occurs. It appears that this happens due to the fact that std::filesystem::path gets "printed" as an STL-like container (it has begin and end methods). However, this is the only "container" that I know of that returns itself when you dereference its iterator. This is exactly what results in an endless recursion.

Essentially, if you are trying to print "C:\Users\b068931" as a path, you will be stuck trying to print "C:". Dereferencing begin iterator returned by path "C:" will also return "C:".

I assume that this can be fixed by providing a template specialization for PrintTo function template. Which I could do, but I believe that it should already be included so as to avoid this strange crash.

Is the feature specific to an operating system, compiler, or build system version?

I have checked cppreference to ensure that this is not a Visual Studio's quirk, however they simply list the value that is returned by begin() as "iterator" without further specifying what it should return when dereferenced. I mainly use Visual Studio, so I am not sure how this works on other IDE's or OSes.