[PATCH] D51561: [CMake] Add support for unittests that have input files

[Reid Kleckner via Phabricator via llvm-commits]

rnk added a comment.

In https://reviews.llvm.org/D51561#1226155, @thakis wrote:

> Sorry, didn't see this earlier. Writing a llvm.srcdir.txt next to every single unit test binary seems like a pretty roundabout way of doing this. How about instead passing the src dir in a runtime flag in http://llvm-cs.pcc.me.uk/utils/lit/lit/formats/googletest.py#107 if the lit config asks for it? Then you don't need to touch the disk to get the src dir path, it's not passed to _all_ binaries, and cmake doesn't have to write a file to disk for every test binary.


To avoid CMake writing so many files, we could make this opt-in. A unittest could pass an option to `add_unittest` or call another cmake function to configure the text file. Or, CMake could test for the presence of $srcdir/Inputs before writing the text file.

I don't think we want to get lit to pass a flag to gtest binaries. Gtest binaries have the nice property that you just run them and they work. It would be a shame to lose that.

In https://reviews.llvm.org/D51561#1226160, @thakis wrote:

> Also also, opening a file from a unit test kind of makes it not a unit test, since those are supposed to not hit the disk etc. Maybe that test wants to be its own binary instead that's called from a lit script, instead of being a unit test?


We may call these "unit" tests, but they're really gtests, and developers everywhere use gtest for more than just unit tests. We already have tests that create temp files. I don't see why reaching back into the source directory for inputs is too heavyweight for us.

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What are you most concerned about, files littering the build directory, cmake runtime, simplicity, or something else?


Repository:
  rL LLVM

https://reviews.llvm.org/D51561