co19/LibTest/io/Link/rename_A02_t03 flaky -> RuntimeError

[alexmarkov]

The test

co19/LibTest/io/Link/rename_A02_t03 RuntimeError (expected Pass)

is failing on configuration

vm-aot-win-debug-x64c

This test was flaky, and now it is failing consistently.

Log:

--- Command "vm_compile_to_kernel" (took 02.000749s):
set DART_CONFIGURATION=DebugX64C & set DART_SUPPRESS_WER=1 & set DART_CRASHPAD_HANDLER=C:\b\s\w\ir\out\DebugX64C\crashpad_handler.exe & C:\b\s\w\ir\pkg\vm\tool\gen_kernel.bat --aot --platform=out/DebugX64C/vm_platform_strong.dill -o C:\b\s\w\ir\out\DebugX64C\generated_compilations\vm-aot-win-debug-x64c\tests_co19_src_LibTest_io_Link_rename_A02_t03\out.dill C:\b\s\w\ir\tests\co19\src\LibTest\io\Link\rename_A02_t03.dart -Dtest_runner.configuration=vm-aot-win-debug-x64c --packages=C:\b\s\w\ir\.dart_tool\package_config.json -Ddart.vm.product=false --sound-null-safety

exit code:
0

--- Command "precompiler" (took 19.000764s):
set DART_CONFIGURATION=DebugX64C & set DART_SUPPRESS_WER=1 & set DART_CRASHPAD_HANDLER=C:\b\s\w\ir\out\DebugX64C\crashpad_handler.exe & out\DebugX64C\gen_snapshot --snapshot-kind=app-aot-elf --elf=C:/b/s/w/ir/out/DebugX64C/generated_compilations/vm-aot-win-debug-x64c/tests_co19_src_LibTest_io_Link_rename_A02_t03/out.aotsnapshot --loading-unit-manifest=C:/b/s/w/ir/out/DebugX64C/generated_compilations/vm-aot-win-debug-x64c/tests_co19_src_LibTest_io_Link_rename_A02_t03/ignored.json --sound-null-safety -Dtest_runner.configuration=vm-aot-win-debug-x64c --ignore-unrecognized-flags --packages=C:\b\s\w\ir\.dart_tool\package_config.json C:\b\s\w\ir\out\DebugX64C\generated_compilations\vm-aot-win-debug-x64c\tests_co19_src_LibTest_io_Link_rename_A02_t03\out.dill

exit code:
0

--- Command "remove_kernel_file" (took 93ms):
set DART_CONFIGURATION=DebugX64C & set DART_SUPPRESS_WER=1 & set DART_CRASHPAD_HANDLER=C:\b\s\w\ir\out\DebugX64C\crashpad_handler.exe & cmd.exe /c del C:\b\s\w\ir\out\DebugX64C\generated_compilations\vm-aot-win-debug-x64c\tests_co19_src_LibTest_io_Link_rename_A02_t03\out.dill

exit code:
0

--- Command "vm" (took 534ms):
set DART_CONFIGURATION=DebugX64C & set DART_SUPPRESS_WER=1 & set DART_CRASHPAD_HANDLER=C:\b\s\w\ir\out\DebugX64C\crashpad_handler.exe & set TEST_COMPILATION_DIR=C:/b/s/w/ir/out/DebugX64C/generated_compilations/vm-aot-win-debug-x64c/tests_co19_src_LibTest_io_Link_rename_A02_t03 & out\DebugX64C\dart_precompiled_runtime.exe --sound-null-safety -Dtest_runner.configuration=vm-aot-win-debug-x64c --ignore-unrecognized-flags --packages=C:\b\s\w\ir\.dart_tool\package_config.json C:/b/s/w/ir/out/DebugX64C/generated_compilations/vm-aot-win-debug-x64c/tests_co19_src_LibTest_io_Link_rename_A02_t03/out.aotsnapshot

exit code:
255

stdout:
unittest-suite-wait-for-done

stderr:
Unhandled exception:
Expect.fail(FileSystemException expected)
#0      _fail (file:///C:/b/s/w/ir/tests/co19/src/Utils/expect.dart:18)
#1      Expect.fail (file:///C:/b/s/w/ir/tests/co19/src/Utils/expect_common.dart:59)
#2      _main.<anonymous closure> (file:///C:/b/s/w/ir/tests/co19/src/LibTest/io/Link/rename_A02_t03.dart:39)
<asynchronous suspension>
#3      _main (file:///C:/b/s/w/ir/tests/co19/src/LibTest/io/Link/rename_A02_t03.dart:38)
<asynchronous suspension>
#4      inSandbox (file:///C:/b/s/w/ir/tests/co19/src/LibTest/io/file_utils.dart:22)
<asynchronous suspension>
#5      main (file:///C:/b/s/w/ir/tests/co19/src/LibTest/io/Link/rename_A02_t03.dart:30)
<asynchronous suspension>

--- Re-run this test:
python3 tools/test.py -n vm-aot-win-debug-x64c co19/LibTest/io/Link/rename_A02_t03

/cc @brianquinlan

[brianquinlan]

I think that the documentation:

If newPath identifies an existing link, that link is removed first. If newPath identifies an existing file or directory, the operation fails and the future completes with an exception.

Does not match the actual behavior. We even have explicit tests that verify that existing files are overwritten.

The code seems to do that deliberately.

[brianquinlan]

I've filed a bug (dart-lang/co19#2284) to modify the co19 tests based on the corrected documentation.