[Clang] Port ulimit tests to work with internal shell

Now that ulimit is implemented for the internal shell, we can make sure
that the clang tests utilizing ulimit actually work. One just needs the
removal of its shell requirement while the other one needs some rework
to avoid bash for loops. These are writtein in Python for about the same
amount of complexity.

Reviewers: ilovepi, cmtice, AaronBallman, Sirraide, petrhosek

Reviewed By: ilovepi

Pull Request: #157977

Author: boomanaiden154

clang/test/PCH/leakfiles.test

@@ -1,9 +1,8 @@
 // Test that compiling using a PCH doesn't leak file descriptors.
 // https://bugs.chromium.org/p/chromium/issues/detail?id=924225
 //
-// This test requires bash loops and ulimit.
-// REQUIRES: shell
-// UNSUPPORTED: target={{.*win32.*}}
+// This test uses ulimit.
+// UNSUPPORTED: system-windows
 //
 // Set up source files. lib/lib.h includes lots of lib*.h files in that dir.
 // client.c includes lib/lib.h, and also the individual files directly.
@@ -12,10 +11,10 @@
 // RUN: mkdir %t
 // RUN: cd %t
 // RUN: mkdir lib
-// RUN: for i in {1..300}; do touch lib/lib$i.h; done
-// RUN: for i in {1..300}; do echo "#include \"lib$i.h\"" >> lib/lib.h; done
+// RUN: %python -c "from pathlib import Path; list(map(lambda i: Path(f'lib/lib{i}.h').touch(), range(1, 301)))"
+// RUN: %python -c "for i in range(1, 301): print(f'#include \"lib{i}.h\"')" > lib/lib.h
 // RUN: echo "#include \"lib/lib.h\"" > client.c
-// RUN: for i in {1..300}; do echo "#include \"lib/lib$i.h\"" >> client.c; done
+// RUN: %python -c "for i in range(1, 301): print(f'#include \"lib/lib{i}.h\"')" > client.c
 //
 // We want to verify that we don't hold all the files open at the same time.
 // This is important e.g. on mac, which has a low default FD limit.

clang/test/SemaCXX/PR51712-large-array-constexpr-check-oom.cpp

@@ -1,7 +1,6 @@
 // Only run this test where ulimit is known to work well.
 // (There's nothing really platform-specific being tested, this is just ulimit).
 //
-// REQUIRES: shell
 // REQUIRES: system-linux
 // UNSUPPORTED: msan
 // UNSUPPORTED: asan