Add unit tests from lldb-eval

[kuilpd]

Add unit tests ported from lldb-eval.

TODO:

• Fix errors in XFailed tests
• Fix segfault errors in GTEST_SKIP tests
• Implement interfaces for scoped, context, and separate parsing and re-enable DISABLED_ tests

[kuilpd]

Since not all test cases were moved to python tests, I added unit tests from lldb-eval to see better what functionality is missing. Notably, a lot of expressions are not making it past the lexer now, many of which can be fixed by solving issue #4

This pull request is just to show the branch. My question is, should we maintain these unit tests or move them one by one to python suite as we fix them?

[kuilpd]

@cmtice
Cleaned up the unit tests:

• Marked currently failing tests as XFail and they will pass until the issue is fixed (every test suite will print the number of these tests in the summary)
• Skipped 3 tests that cause a segfault, marked by GTEST_SKIP
• Added placeholders for currently unimplemented functionality: scope evaluation, evaluation with context, separate parsing. They return an error when running a relevant test
• Disabled all the test that use unimplemented functionality, marked by DISABLED_ and printed out at the end of unit test summary

Haven't figured out yet how to build the test binary from source and pass it to the unit tests, so for now it's still a pre-built binary.
If it doesn't work on your PC, clang++ -O0 -g -stdlib=libc++ test_binary.cc -o test_binary_libc++.bin in lldb/unittests/DIL/Inputs directory will rebuild it for your system.

Please try launching the tests and tell me how it goes :)
If it works decent enough, we can merge it to main and then fix the tests along with bugs in other pull requests.

[kuilpd]

@cmtice
Added a way to compile the test binary with the in-tree clang. It's kind of hacky, requires clang and lld projects enabled, and libc++ installed in the system (some of the tests depend specifically on being linked against libc++, I will probably adjust that later)

[cmtice]

Suggested change

	COMMAND $<TARGET_FILE:clang> test_binary.cc -std=c++17 -fuse-ld=lld -B$<TARGET_FILE:lld>
	COMMAND $<TARGET_FILE:clang> ${CMAKE_CURRENT_SOURCE_DIR}/test_binary.cc -std=c++17 -fuse-ld=lld -B$<TARGET_FILE:lld>

[cmtice]

I found that I needed to tell clang what directory to look in, for building test_binary.cc

[cmtice]

I found that with the small change I've shown above, the unittest builds & runs for me. I get 2 failures:
[ FAILED ] 2 tests, listed below:
[ FAILED ] EvalTest.TestCxxReinterpretCast
[ FAILED ] EvalTest.TestUniquePtr

[kuilpd]

Hmm, these are the tests that fail when I link against libstdc++.
I should add checks for which library is used anyway, will do that next.

[kuilpd]

@cmtice
Added linking against in-tree libc++ and adjusted tests accordingly, so that there is no ambiguity about which library is used.
Just need to enable runtimes libcxx;libcxxabi;libunwind in the project.

[kuilpd]

@cmtice Could you please check if the tests work after the last changes?

[cmtice]

@cmtice Could you please check if the tests work after the last changes?

The tests build just fine. When I run them I get the following results:
[ PASSED ] 60 tests.
[ SKIPPED ] 3 tests, listed below:
[ SKIPPED ] EvalTest.TestCStyleCastPointer
[ SKIPPED ] EvalTest.TestCxxStaticCast
[ SKIPPED ] EvalTest.TestTernaryOperator
[ FAILED ] 1 test, listed below:
[ FAILED ] EvalTest.TestCxxReinterpretCast

1 FAILED TEST
YOU HAVE 23 DISABLED TESTS

[kuilpd]

Okay, disabled and skipped tests are supposed to be there, but nothing should fail. What are the errors?

[cmtice]

Okay, disabled and skipped tests are supposed to be there, but nothing should fail. What are the errors?

[ RUN ] EvalTest.TestCxxReinterpretCast
/usr/local/google3/cmtice/access-softek-dil/lldb/unittests/DIL/DILTests.cpp:1779: Failure
Value of: Eval("reinterpret_cast<nullptr_t>(ptr)")
Expected: evaluates with an error: 'reinterpret_cast from 'int *' to 'nullptr_t' (canonically referred to as 'std::nullptr_t') is not allowed'
Actual: { DIL: NULL, lldb: NULL }, error:
:1:18: unknown type name 'nullptr_t'
reinterpret_cast<nullptr_t>(ptr)
^

/usr/local/google3/cmtice/access-softek-dil/lldb/unittests/DIL/DILTests.cpp:1783: Failure
Value of: Eval("reinterpret_cast<nullptr_t>(0)")
Expected: evaluates with an error: 'reinterpret_cast from 'int' to 'nullptr_t' (canonically referred to as 'std::nullptr_t') is not allowed'
Actual: { DIL: NULL, lldb: NULL }, error:
:1:18: unknown type name 'nullptr_t'
reinterpret_cast<nullptr_t>(0)
^

/usr/local/google3/cmtice/access-softek-dil/lldb/unittests/DIL/DILTests.cpp:1787: Failure
Value of: Eval("reinterpret_cast<nullptr_t>(nullptr)")
Expected: evaluates with an error: 'reinterpret_cast from 'std::nullptr_t' to 'nullptr_t' (canonically referred to as 'std::nullptr_t') is not allowed'
Actual: { DIL: NULL, lldb: NULL }, error:
:1:18: unknown type name 'nullptr_t'
reinterpret_cast<nullptr_t>(nullptr)
^

[kuilpd]

I skipped these tests for now, it's just the error message not matching exactly, will figure it out later why do they match on my build, but not on yours.
If none of the tests fail now, I guess we can merge?

[cmtice]

I skipped these tests for now, it's just the error message not matching exactly, will figure it out later why do they match on my build, but not on yours. If none of the tests fail now, I guess we can merge?

SGTM!

[kuilpd]

I misunderstood how GTEST_SKIP() works, it skips the rest of the test fixture and marks it skipped, so I moved the tests I want to skip to the end of their fixture.