test: test_bitcoin: allow -testdatadir=<datadir>

Specifying this argument overrides the path location for test_bitcoin;
it becomes <datadir>/test_common_Bitcoin Core/<testname>/datadir. Also,
this directory isn't removed after the test completes. This can make it
easier for developers to study the results of a test (see the state of
the data directory after the test runs), and also (for example) have an
editor open on debug.log to monitor it across multiple test runs instead
of having to re-open a different pathname each time.

Example usage (note the "--" is needed):

test_bitcoin --run_test=getarg_tests/boolarg -- \
-testdatadir=/somewhere/mydatadir

This will create (if necessary) and use the data directory:

/somewhere/mydatadir/test_common_Bitcoin Core/getarg_tests/boolarg/datadir

Co-authored-by: furszy <mfurszy@protonmail.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/src/qt/test/test_main.cpp b/src/qt/test/test_main.cpp
index e45fc1ced8..8c09e9f540 100644
--- a/src/qt/test/test_main.cpp
+++ b/src/qt/test/test_main.cpp
@@ -48,6 +48,8 @@ const std::function<void(const std::string&)> G_TEST_LOG_FUN{};
 
 const std::function<std::vector<const char*>()> G_TEST_COMMAND_LINE_ARGUMENTS{};
 
+const std::function<std::string()> G_TEST_GET_FULL_NAME{};
+
 // This is all you need to run all the tests
 int main(int argc, char* argv[])
 {