76d44e832f
2f5fd3cf92test: Correctly decode UTF-8 literal string paths (Ryan Ofsky) Pull request description: Call `fs::u8path()` to convert some UTF-8 string literals to paths, instead of relying on the implicit conversion. Fake Macro pointed out in https://github.com/bitcoin/bitcoin/pull/24306#discussion_r818566106 that `fs_tests` are incorrectly decoding some literal UTF-8 paths using the current windows codepage, instead of treating them as UTF-8. This could cause test failures depending what environment windows tests are run under. The `fs::path` class exists to avoid problems like this, but because it is lenient with `const char*` conversions, under assumption that they are ["safe as long as the literals are ASCII"](727b0cb592/src/fs.h (L39)), bugs like this are still possible. If we think this is a concern, followup options to try to prevent this bug in the future are: 0. Do nothing 1. Improve the "safe as long as the literals are ASCII" comment. Make it clear that non-ASCII strings are invalid. 2. Drop the implicit `const char*` conversion functions. This would be nice because it would simplifify the `fs::path` class a little, while making it safer. Drawback is that it would require some more verbosity from callers. For example, instead of `GetDataDirNet() / "mempool.dat"` they would have to write `GetDataDirNet() / fs::u8path("mempool.dat")` 3. Keep the implicit `const char*` conversion functions, but make them call `fs::u8path()` internally. Change the "safe as long as the literals are *ASCII*" comment to "safe as long as the literals are *UTF-8*". I'd be happy with 0, 1, or 2. I'd be a little resistant to 3 even though it was would add more safety, because it would slightly increase complexity, and because I think it would encourage representing paths as strings, when I think there are so many footguns associated with paths as strings, that it's best to convert strings to paths at the earliest point possible, and convert paths to strings at the latest point possible. ACKs for top commit: laanwj: Code review ACK2f5fd3cf92w0xlt: crACK2f5fd3cTree-SHA512: 9c56714744592094d873b79843b526d20f31ed05eff957d698368d66025764eae8bfd5305d5f7b6cc38803f0d85fa5552003e5c6cacf1e076ea6d313bcbc960c
Unit tests
The sources in this directory are unit test cases. Boost includes a unit testing framework, and since Bitcoin Core already uses Boost, it makes sense to simply use this framework rather than require developers to configure some other framework (we want as few impediments to creating unit tests as possible).
The build system is set up to compile an executable called test_bitcoin
that runs all of the unit tests. The main source file for the test library is found in
util/setup_common.cpp.
Compiling/running unit tests
Unit tests will be automatically compiled if dependencies were met in ./configure
and tests weren't explicitly disabled.
After configuring, they can be run with make check.
To run the unit tests manually, launch src/test/test_bitcoin. To recompile
after a test file was modified, run make and then run the test again. If you
modify a non-test file, use make -C src/test to recompile only what's needed
to run the unit tests.
To add more unit tests, add BOOST_AUTO_TEST_CASE functions to the existing
.cpp files in the test/ directory or add new .cpp files that
implement new BOOST_AUTO_TEST_SUITE sections.
To run the GUI unit tests manually, launch src/qt/test/test_bitcoin-qt
To add more GUI unit tests, add them to the src/qt/test/ directory and
the src/qt/test/test_main.cpp file.
Running individual tests
test_bitcoin accepts the command line arguments from the boost framework.
For example, to run just the getarg_tests suite of tests:
test_bitcoin --log_level=all --run_test=getarg_tests
log_level controls the verbosity of the test framework, which logs when a
test case is entered, for example. test_bitcoin also accepts the command
line arguments accepted by bitcoind. Use -- to separate both types of
arguments:
test_bitcoin --log_level=all --run_test=getarg_tests -- -printtoconsole=1
The -printtoconsole=1 after the two dashes redirects the debug log, which
would normally go to a file in the test datadir
(BasicTestingSetup::m_path_root), to the standard terminal output.
... or to run just the doubledash test:
test_bitcoin --run_test=getarg_tests/doubledash
Run test_bitcoin --help for the full list.
Adding test cases
To add a new unit test file to our test suite you need
to add the file to src/Makefile.test.include. The pattern is to create
one test file for each class or source file for which you want to create
unit tests. The file naming convention is <source_filename>_tests.cpp
and such files should wrap their tests in a test suite
called <source_filename>_tests. For an example of this pattern,
see uint256_tests.cpp.
Logging and debugging in unit tests
make check will write to a log file foo_tests.cpp.log and display this file
on failure. For running individual tests verbosely, refer to the section
above.
To write to logs from unit tests you need to use specific message methods
provided by Boost. The simplest is BOOST_TEST_MESSAGE.
For debugging you can launch the test_bitcoin executable with gdb or lldb and
start debugging, just like you would with any other program:
gdb src/test/test_bitcoin
Segmentation faults
If you hit a segmentation fault during a test run, you can diagnose where the fault
is happening by running gdb ./src/test/test_bitcoin and then using the bt command
within gdb.
Another tool that can be used to resolve segmentation faults is valgrind.
If for whatever reason you want to produce a core dump file for this fault, you can do
that as well. By default, the boost test runner will intercept system errors and not
produce a core file. To bypass this, add --catch_system_errors=no to the
test_bitcoin arguments and ensure that your ulimits are set properly (e.g. ulimit -c unlimited).
Running the tests and hitting a segmentation fault should now produce a file called core
(on Linux platforms, the file name will likely depend on the contents of
/proc/sys/kernel/core_pattern).
You can then explore the core dump using
gdb src/test/test_bitcoin core
(gbd) bt # produce a backtrace for where a segfault occurred