Wladimir J. van der Laan b8740d6737
Merge #18468: Span improvements
26acc8dd9b512f220c1facdba2c5de7976d3c258 Add sanity check asserts to span when -DDEBUG (Pieter Wuille)
2676aeadfa0e43dcaaccc4720623cdfe0beed528 Simplify usage of Span in several places (Pieter Wuille)
ab303a16d114b1e94c6cf0e4c5db5389dfa197f6 Add Span constructors for arrays and vectors (Pieter Wuille)
bb3d38fc061d8482e68cd335a45c9cd8bb66a475 Make pointer-based Span construction safer (Pieter Wuille)
1f790a1147ad9a5fe06987d84b6cd71f91cbec4b Make Span size type unsigned (Pieter Wuille)

Pull request description:

  This improves our Span class by making it closer to the C++20 `std::span` one:
  * ~~Support conversion between compatible Spans (e.g. `Span<char>` to `Span<const char>`).~~ (done in #18591)
  * Make the size type `std::size_t` rather than `std::ptrdiff_t` (the C++20 one underwent the same change).
  * Support construction of Spans directly from arrays, `std::string`s, `std::array`s, `std::vector`s, `prevector`s, ... (for all but arrays, this only works for const containers to prevent surprises).

  And then make use of those improvements in various call sites.

  I realize the template magic used looks scary, but it's only needed to make overload resultion make the right choices. Note that the operations done on values are all extremely simple: no casts, explicit conversions, or warning-silencing constructions. That should hopefully make it simpler to review.

ACKs for top commit:
  laanwj:
    Code review ACK 26acc8dd9b512f220c1facdba2c5de7976d3c258
  promag:
    Code review ACK 26acc8dd9b512f220c1facdba2c5de7976d3c258.

Tree-SHA512: 5a5bd346a140edf782b5b3b3f04d9160c7b9e9def35159814a07780ab1dd352545b88d3cc491e0f80d161f829c49ebfb952fddc9180f1a56f1257aa51f38788a
2020-06-18 14:12:21 +02:00
..
2020-06-18 14:12:21 +02:00
2020-04-16 13:33:09 -04:00
2020-03-31 17:11:47 -04:00

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 has some built-in command-line arguments; for example, to run just the getarg_tests verbosely:

test_bitcoin --log_level=all --run_test=getarg_tests -- DEBUG_LOG_OUT

log_level controls the verbosity of the test framework, which logs when a test case is entered, for example. The DEBUG_LOG_OUT 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 gdbor lldb and start debugging, just like you would with any other program:

gdb src/test/test_bitcoin