avoid setting {BITCOIND,ELEMENTSD}_EXE in setup

The logic of setting the env var inside the setup prevents user of other
OS like nixos to run the tests (because the included binary are not
working on nixos).
Setting those env vars is meant to be done in the dev environment not in
the code.
With this users with `bitcoind` and `elementsd` in their PATH will work
too.
The CI script will set the variables only if they are not already set.
(Allowing Nixos users to override and run it locally)

bitcoind-tests/tests/setup/mod.rs

@@ -17,14 +17,6 @@ pub mod test_util;
 // We are not using pegins right now, but it might be required in case in future
 // if we extend the tests to check pegins etc.
 pub fn setup(validate_pegin: bool) -> (ElementsD, Option<BitcoinD>, elements::BlockHash) {
-    // Lookup bitcoind binary path
-    let curr_dir = std::env::current_dir().unwrap();
-    let bitcoind_path = curr_dir.join("bin/bitcoind");
-    let elementsd_path = curr_dir.join("bin/elementsd");
-
-    std::env::set_var("BITCOIND_EXE", bitcoind_path);
-    std::env::set_var("ELEMENTSD_EXE", elementsd_path);
-
     let mut bitcoind = None;
     if validate_pegin {
         let bitcoind_exe = bitcoind::exe_path().unwrap();

contrib/test.sh

@@ -22,7 +22,14 @@ fi
 
 # Test bitcoind integration tests if told to (this only works with the stable toolchain)
 if [ "$DO_BITCOIND_TESTS" = true ]; then
+
+    BITCOIND_EXE_DEFAULT="$(git rev-parse --show-toplevel)/bitcoind-tests/bin/bitcoind"
+    ELEMENTSD_EXE_DEFAULT="$(git rev-parse --show-toplevel)/bitcoind-tests/bin/elementsd"
+
     cd bitcoind-tests
+
+    BITCOIND_EXE=${BITCOIND_EXE:=${BITCOIND_EXE_DEFAULT}} \
+    ELEMENTSD_EXE=${ELEMENTSD_EXE:=${ELEMENTSD_EXE_DEFAULT}} \
     cargo test --verbose
 
     # Exit integration tests, do not run other tests.