[libcxx-commits] [libcxx] [libcxx][test] Fix empty.gen selftest on windows (PR #69403)

[via libcxx-commits]

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@@ -8,4 +8,4 @@
 
 // Make sure the test passes if it succeeds to run
 
-// RUN: true
+// RUN: :
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dyung wrote:

> Lit's test suite has [tests where RUN lines containing true/false execute with lit's internal shell](https://github.com/llvm/llvm-project/blob/main/llvm/utils/lit/tests/Inputs/shtest-run-at-line/internal-shell/basic.txt) (not bash), and they [appear to succeed in windows bots](https://lab.llvm.org/buildbot/#/builders/216). That suggests to me that true/false are available as external commands there. Maybe @dyung can shed some light on that setup.
> 
> Is the goal of this patch to relax windows installation requirements, or am I just misunderstanding what's happening?

I'm not completely sure what is being asked here, but I took a look at our Windows bot that @jdenny-ornl linked to and while there is a true.exe that seems to be installed with git (C:\Program Files\Git\usr\bin), but unless something is adding that directory to the path during testing, it is NOT a part of the regular path. And indeed, trying to run "true" from a command prompt gives the expected error `'true' is not recognized as an internal or external command, operable program or batch file.`.

https://github.com/llvm/llvm-project/pull/69403