[libcxx-commits] [libcxx] [libc++] Fix unnecessary flushes in std::print() on POSIX (PR #70321)

[Nikolas Klauser via libcxx-commits]

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@@ -59,43 +59,19 @@ scoped_test_env env;
 std::string filename = env.create_file("output.txt");
 
 static void test_basics() {
-  FILE* file = std::fopen(filename.c_str(), "wb");
-  assert(file);
-
-  // Test writing to a "non-terminal" stream does not call WriteConsoleW.
-  std::__print::__vprint_unicode_windows(file, "Hello", std::make_format_args(), false, false);
-  assert(std::ftell(file) == 5);
-
   // It's not possible to reliably test whether writing to a "terminal" stream
   // flushes before writing. Testing flushing a closed stream worked on some
   // platforms, but was unreliable.
   calling = true;
-  std::__print::__vprint_unicode_windows(file, " world", std::make_format_args(), false, true);
+  std::__print::__vprint_unicode_windows(stdout, " world", std::make_format_args(), false);
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philnik777 wrote:

We should almost certainly not be using `stdout` here, since that's used by the test runner and we should avoid trashing that. Why did you change this test in general?

https://github.com/llvm/llvm-project/pull/70321