llvm-project/llvm/utils/unittest/CMakeLists.txt

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########################################################################
# Experimental CMake build script for Google Test.
#
# Consider this a prototype. It will change drastically. For now,
# this is only for people on the cutting edge.
#
# To run the tests for Google Test itself on Linux, use 'make test' or
# ctest. You can select which tests to run using 'ctest -R regex'.
# For more options, run 'ctest --help'.
########################################################################
#
# Project-wide settings
# Where gtest's .h files can be found.
include_directories(
googletest/include
googletest
Add the 'googlemock' component of Google Test to LLVM's unittest libraries. I have two immediate motivations for adding this: 1) It makes writing expectations in tests *dramatically* easier. A quick example that is a taste of what is possible: std::vector<int> v = ...; EXPECT_THAT(v, UnorderedElementsAre(1, 2, 3)); This checks that v contains '1', '2', and '3' in some order. There are a wealth of other helpful matchers like this. They tend to be highly generic and STL-friendly so they will in almost all cases work out of the box even on custom LLVM data structures. I actually find the matcher syntax substantially easier to read even for simple assertions: EXPECT_THAT(a, Eq(b)); EXPECT_THAT(b, Ne(c)); Both of these make it clear what is being *tested* and what is being *expected*. With `EXPECT_EQ` this is implicit (the LHS is expected, the RHS is tested) and often confusing. With `EXPECT_NE` it is just not clear. Even the failure error messages are superior with the matcher based expectations. 2) When testing any kind of generic code, you are continually defining dummy types with interfaces and then trying to check that the interfaces are manipulated in a particular way. This is actually what mocks are *good* for -- testing *interface interactions*. With generic code, there is often no "fake" or other object that can be used. For a concrete example of where this is currently causing significant pain, look at the pass manager unittests which are riddled with counters incremented when methods are called. All of these could be replaced with mocks. The result would be more effective at testing the code by having tighter constraints. It would be substantially more readable and maintainable when updating the code. And the error messages on failure would have substantially more information as mocks automatically record stack traces and other information *when the API is misused* instead of trying to diagnose it after the fact. I expect that #1 will be the overwhelming majority of the uses of gmock, but I think that is sufficient to justify having it. I would actually like to update the coding standards to encourage the use of matchers rather than any other form of `EXPECT_...` macros as they are IMO a strict superset in terms of functionality and readability. I think that #2 is relatively rarely useful, but there *are* cases where it is useful. Historically, I think misuse of actual mocking as described in #2 has led to resistance towards this framework. I am actually sympathetic to this -- mocking can easily be overused. However I think this is not a significant concern in LLVM. First and foremost, LLVM has very careful and rare exposure of abstract interfaces or dependency injection, which are the most prone to abuse with mocks. So there are few opportunities to abuse them. Second, a large fraction of LLVM's unittests are testing *generic code* where mocks actually make tremendous sense. And gmock is well suited to building interfaces that exercise generic libraries. Finally, I still think we should be willing to have testing utilities in tree even if they should be used rarely. We can use code review to help guide the usage here. For a longer and more complete discussion of this, see the llvm-dev thread here: http://lists.llvm.org/pipermail/llvm-dev/2017-January/108672.html The general consensus seems that this is a reasonable direction to start down, but that doesn't mean we should race ahead and use this everywhere. I have one test that is blocked on this to land and that was specifically used as an example. Before widespread adoption, I'm going to work up some (brief) guidelines as some of these facilities should be used sparingly and carefully. Differential Revision: https://reviews.llvm.org/D28156 llvm-svn: 291606
2017-01-11 06:32:26 +08:00
googlemock/include
googlemock
)
# LLVM requires C++11 but gtest doesn't correctly detect the availability
# of C++11 on MSVC, so we force it on.
add_definitions(-DGTEST_LANG_CXX11=1)
add_definitions(-DGTEST_HAS_TR1_TUPLE=0)
if(WIN32)
add_definitions(-DGTEST_OS_WINDOWS=1)
endif()
if(SUPPORTS_VARIADIC_MACROS_FLAG)
add_definitions("-Wno-variadic-macros")
endif()
if(SUPPORTS_GNU_ZERO_VARIADIC_MACRO_ARGUMENTS_FLAG)
add_definitions("-Wno-gnu-zero-variadic-macro-arguments")
endif()
if(CXX_SUPPORTS_COVERED_SWITCH_DEFAULT_FLAG)
add_definitions("-Wno-covered-switch-default")
endif()
set(LLVM_REQUIRES_RTTI 1)
add_definitions( -DGTEST_HAS_RTTI=0 )
if (NOT LLVM_ENABLE_THREADS)
add_definitions( -DGTEST_HAS_PTHREAD=0 )
endif()
find_library(LLVM_PTHREAD_LIBRARY_PATH pthread)
if (LLVM_PTHREAD_LIBRARY_PATH)
list(APPEND LIBS pthread)
endif()
add_llvm_library(gtest
googletest/src/gtest-all.cc
Add the 'googlemock' component of Google Test to LLVM's unittest libraries. I have two immediate motivations for adding this: 1) It makes writing expectations in tests *dramatically* easier. A quick example that is a taste of what is possible: std::vector<int> v = ...; EXPECT_THAT(v, UnorderedElementsAre(1, 2, 3)); This checks that v contains '1', '2', and '3' in some order. There are a wealth of other helpful matchers like this. They tend to be highly generic and STL-friendly so they will in almost all cases work out of the box even on custom LLVM data structures. I actually find the matcher syntax substantially easier to read even for simple assertions: EXPECT_THAT(a, Eq(b)); EXPECT_THAT(b, Ne(c)); Both of these make it clear what is being *tested* and what is being *expected*. With `EXPECT_EQ` this is implicit (the LHS is expected, the RHS is tested) and often confusing. With `EXPECT_NE` it is just not clear. Even the failure error messages are superior with the matcher based expectations. 2) When testing any kind of generic code, you are continually defining dummy types with interfaces and then trying to check that the interfaces are manipulated in a particular way. This is actually what mocks are *good* for -- testing *interface interactions*. With generic code, there is often no "fake" or other object that can be used. For a concrete example of where this is currently causing significant pain, look at the pass manager unittests which are riddled with counters incremented when methods are called. All of these could be replaced with mocks. The result would be more effective at testing the code by having tighter constraints. It would be substantially more readable and maintainable when updating the code. And the error messages on failure would have substantially more information as mocks automatically record stack traces and other information *when the API is misused* instead of trying to diagnose it after the fact. I expect that #1 will be the overwhelming majority of the uses of gmock, but I think that is sufficient to justify having it. I would actually like to update the coding standards to encourage the use of matchers rather than any other form of `EXPECT_...` macros as they are IMO a strict superset in terms of functionality and readability. I think that #2 is relatively rarely useful, but there *are* cases where it is useful. Historically, I think misuse of actual mocking as described in #2 has led to resistance towards this framework. I am actually sympathetic to this -- mocking can easily be overused. However I think this is not a significant concern in LLVM. First and foremost, LLVM has very careful and rare exposure of abstract interfaces or dependency injection, which are the most prone to abuse with mocks. So there are few opportunities to abuse them. Second, a large fraction of LLVM's unittests are testing *generic code* where mocks actually make tremendous sense. And gmock is well suited to building interfaces that exercise generic libraries. Finally, I still think we should be willing to have testing utilities in tree even if they should be used rarely. We can use code review to help guide the usage here. For a longer and more complete discussion of this, see the llvm-dev thread here: http://lists.llvm.org/pipermail/llvm-dev/2017-January/108672.html The general consensus seems that this is a reasonable direction to start down, but that doesn't mean we should race ahead and use this everywhere. I have one test that is blocked on this to land and that was specifically used as an example. Before widespread adoption, I'm going to work up some (brief) guidelines as some of these facilities should be used sparingly and carefully. Differential Revision: https://reviews.llvm.org/D28156 llvm-svn: 291606
2017-01-11 06:32:26 +08:00
googlemock/src/gmock-all.cc
LINK_LIBS
${LIBS}
LINK_COMPONENTS
Support # Depends on llvm::raw_ostream
[cmake] Export gtest/gtest_main and its dependencies via a special build tree only cmake exports file. Previously, gtest/gtest_main were not exported via cmake. The intention here was to ensure that users whom are linking against the LLVM install tree would not get the gtest/gtest_main targets. This prevents downstream projects that link against the LLVM build tree (i.e. Swift) from getting this dependency information in their cmake builds. Without such dependency information, linker issues can result on linux due to LLVMSupport being put before gtest on the linker command line. This commit preserves behavior that we want for the install tree, while adding support for the build tree by: 1. The special casing for gtest/gtest_main in the add_llvm_library code is removed in favor of a flag called "BUILDTREE_ONLY". If this is set, then the library is communicating that it is only meant to be exported into the build tree and is not meant to be installed or exported via the install tree. This part is just a tweak to remove the special case, the underlying code is the same. 2. The cmake code that exports cmake targets for the build tree has special code to import an additional targets file called LLVMBuildTreeOnlyExports.cmake. Additionally the extra targets are added to the LLVMConfig.cmake's LLVM_EXPORTED_TARGETS variable. In contrast, the "installation" cmake file uses the normal LLVM_EXPORTS_TARGETS as before and does not include the extra exports file. This is implemented by defining/undefining variables when performing a configure of the build/install tree LLVMConfig.cmake files. llvm-svn: 281085
2016-09-10 03:45:34 +08:00
# This is a library meant only for the build tree.
BUILDTREE_ONLY
)
add_subdirectory(UnitTestMain)